screen_brightness_control

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import platform
import struct
import threading
import time
import traceback
from functools import lru_cache
from typing import Any, List, Optional, Tuple, Union

from ._version import __author__, __version__  # noqa: F401


def get_brightness(
    display: Optional[Union[int, str]] = None,
    method: Optional[str] = None,
    verbose_error: bool = False
) -> List[int]:
    '''
    Returns the current display brightness

    Args:
        display (str or int): the specific display to query
        method (str): the way in which displays will be accessed.
            On Windows this can be 'wmi' or 'vcp'.
            On Linux it's 'light', 'xrandr', 'ddcutil' or 'xbacklight'.
        verbose_error (bool): controls the level of detail in the error messages

    Returns:
        list: a list of integers (from 0 to 100), each integer being the
            percentage brightness of a display (invalid displays may return None)

    Example:
        ```python
        import screen_brightness_control as sbc

        # get the current screen brightness (for all detected displays)
        current_brightness = sbc.get_brightness()

        # get the brightness of the primary display
        primary_brightness = sbc.get_brightness(display=0)

        # get the brightness of the secondary display (if connected)
        secondary_brightness = sbc.get_brightness(display=1)
        ```
    '''
    return __brightness(display=display, method=method, meta_method='get', verbose_error=verbose_error)


def set_brightness(
    value: Union[int, float, str],
    display: Optional[Union[str, int]] = None,
    method: Optional[str] = None,
    force: bool = False,
    verbose_error: bool = False,
    no_return: bool = True
) -> Union[None, List[int]]:
    '''
    Sets the screen brightness

    Args:
        value (int or float or str): a value 0 to 100. This is a percentage or a string as '+5' or '-5'
        display (int or str): the specific display to adjust
        method (str): the way in which displays will be accessed.
            On Windows this can be 'wmi' or 'vcp'.
            On Linux it's 'light', 'xrandr', 'ddcutil' or 'xbacklight'.
        force (bool): [*Linux Only*] if False the brightness will never be set lower than 1.
            This is because on most displays a brightness of 0 will turn off the backlight.
            If True, this check is bypassed
        verbose_error (bool): boolean value controls the amount of detail error messages will contain
        no_return (bool): if False, this function returns new brightness (by calling `get_brightness`).
            If True, this function returns None (default behaviour).

    Returns:
        None: if the `no_return` kwarg is `True`
        list: a list of integers (from 0 to 100), each integer being the
            percentage brightness of a display (invalid displays may return None)

    Example:
        ```python
        import screen_brightness_control as sbc

        # set brightness to 50%
        sbc.set_brightness(50)

        # set brightness to 0%
        sbc.set_brightness(0, force=True)

        # increase brightness by 25%
        sbc.set_brightness('+25')

        # decrease brightness by 30%
        sbc.set_brightness('-30')

        # set the brightness of display 0 to 50%
        sbc.set_brightness(50, display=0)
        ```
    '''
    if isinstance(value, str) and ('+' in value or '-' in value):
        value = int(float(value))
        monitors = filter_monitors(display=display, method=method)
        if len(monitors) > 1:
            output = []
            for monitor in monitors:
                identifier = Monitor.get_identifier(monitor)[1]
                output.append(
                    set_brightness(
                        get_brightness(display=identifier)[0] + value,
                        display=identifier,
                        force=force,
                        verbose_error=verbose_error,
                        no_return=no_return
                    )
                )
            return flatten_list(output)

        value += get_brightness(display=Monitor.get_identifier(monitors[0])[1])[0]
    else:
        value = int(float(str(value)))

    # make sure value is within bounds
    value = max(min(100, value), 0)

    if platform.system() == 'Linux' and not force:
        value = max(1, value)

    return __brightness(
        value, display=display, method=method,
        meta_method='set', no_return=no_return,
        verbose_error=verbose_error
    )


def fade_brightness(
    finish: Union[int, str],
    start: Optional[Union[int, str]] = None,
    interval: float = 0.01,
    increment: int = 1,
    blocking: bool = True,
    **kwargs
) -> Union[List[threading.Thread], List[int]]:
    '''
    A function to somewhat gently fade the screen brightness from `start` to `finish`

    Args:
        finish (int or str): the brightness level to end up on
        start (int or str): where the brightness should fade from.
            If not specified the function starts from the current screen brightness
        interval (float or int): the time delay between each step in brightness
        increment (int): the amount to change the brightness by per step
        blocking (bool): whether this should occur in the main thread (`True`) or a new daemonic thread (`False`)
        kwargs (dict): passed directly to `set_brightness`.
            Any compatible kwargs are passed to `filter_monitors` as well. (eg: display, method...)

    Returns:
        list: list of `threading.Thread` objects if `blocking == False`,
            otherwise it returns the result of `get_brightness()`

    Example:
        ```python
        import screen_brightness_control as sbc

        # fade brightness from the current brightness to 50%
        sbc.fade_brightness(50)

        # fade the brightness from 25% to 75%
        sbc.fade_brightness(75, start=25)

        # fade the brightness from the current value to 100% in steps of 10%
        sbc.fade_brightness(100, increment=10)

        # fade the brightness from 100% to 90% with time intervals of 0.1 seconds
        sbc.fade_brightness(90, start=100, interval=0.1)

        # fade the brightness to 100% in a new thread
        sbc.fade_brightness(100, blocking=False)
        ```
    '''
    def fade(start, finish, increment, monitor):
        for i in range(min(start, finish), max(start, finish), increment):
            val = i
            if start > finish:
                val = start - (val - finish)
            monitor.set_brightness(val, no_return=True)
            time.sleep(interval)

        if monitor.get_brightness() != finish:
            monitor.set_brightness(finish, no_return=True)

    def err_msg(e):
        return f'\n\tfilter_monitors -> {type(e).__name__}: {e}'

    try:
        # make sure only compatible kwargs are passed to filter_monitors
        available_monitors = filter_monitors(
            **{k: v for k, v in kwargs.items() if k in (
                'display', 'haystack', 'method', 'include'
            )}
        )
    except (LookupError, ValueError) as e:
        if not platform.system() == 'Linux':
            raise ScreenBrightnessError(err_msg(e)) from e

        method = kwargs.get('method', None)
        if isinstance(e, LookupError) and method is None:
            # if a user ONLY has XBacklight installed and no method was specified
            # then filter_monitors will raise a LookupError. In this case, default to using
            # linux.XBacklight method
            available_monitors = [_OS_MODULE.XBacklight]
        elif isinstance(e, ValueError) and method.lower() == 'xbacklight':
            # low level `list_monitors_info` will raise a ValueError if 'xbacklight' is passed as the method
            # because xbacklight cannot query individual monitor information
            available_monitors = [_OS_MODULE.XBacklight]
        else:
            raise ScreenBrightnessError(err_msg(e)) from e

    except Exception as e:
        raise ScreenBrightnessError(err_msg(e)) from e

    threads = []
    for i in available_monitors:
        try:
            if platform.system() == 'Linux' and i == _OS_MODULE.XBacklight:
                monitor = i
            else:
                monitor = Monitor(i)

            # same effect as monitor.is_active()
            current = monitor.get_brightness()
            st, fi = start, finish
            # convert strings like '+5' to an actual brightness value
            if isinstance(fi, str):
                if "+" in fi or "-" in fi:
                    fi = current + int(float(fi))
            if isinstance(st, str):
                if "+" in st or "-" in st:
                    st = current + int(float(st))

            st = current if st is None else st
            # make sure both values are within the correct range
            fi = min(max(int(float(fi)), 0), 100)
            st = min(max(int(float(st)), 0), 100)

            t1 = threading.Thread(target=fade, args=(st, fi, increment, monitor))
            t1.start()
            threads.append(t1)
        except Exception:
            pass

    if not blocking:
        return threads

    for t in threads:
        t.join()
    return get_brightness(**kwargs)


def list_monitors_info(method: Optional[str] = None, allow_duplicates: bool = False) -> List[dict]:
    '''
    list detailed information about all monitors that are controllable by this library

    Args:
        method (str): the method to use to list the available monitors.
            On Windows this can be `'wmi'` or `'vcp'`.
            On Linux this can be `'light'`, `'xrandr'`, `'ddcutil'` or `'sysfiles'`.
        allow_duplicates (bool): whether to filter out duplicate displays or not

    Returns:
        list: list of dictionaries

    Example:
        ```python
        import screen_brightness_control as sbc
        monitors = sbc.list_monitors_info()
        for monitor in monitors:
            print('=======================')
            # the manufacturer name plus the model
            print('Name:', monitor['name'])
            # the general model of the display
            print('Model:', monitor['model'])
            # the serial of the display
            print('Serial:', monitor['serial'])
            # the name of the brand of the monitor
            print('Manufacturer:', monitor['manufacturer'])
            # the 3 letter code corresponding to the brand name, EG: BNQ -> BenQ
            print('Manufacturer ID:', monitor['manufacturer_id'])
            # the index of that display FOR THE SPECIFIC METHOD THE DISPLAY USES
            print('Index:', monitor['index'])
            # the method this monitor can be addressed by
            print('Method:', monitor['method'])
            # the EDID string associated with that monitor
            print('EDID:', monitor['edid'])
        ```
    '''
    info = __cache__.get('monitors_info', method=method, allow_duplicates=allow_duplicates)
    if info is None:
        info = _OS_MODULE.list_monitors_info(method=method, allow_duplicates=allow_duplicates)
        __cache__.store('monitors_info', info, method=method, allow_duplicates=allow_duplicates)
    return info


def list_monitors(method: Optional[str] = None) -> List[str]:
    '''
    List the names of all detected monitors

    Args:
        method (str): the method to use to list the available monitors.
            On Windows this can be `'wmi'` or `'vcp'`.
            On Linux this can be `'light'`, `'xrandr'`, `'ddcutil'` or `'sysfiles'`.

    Returns:
        list: list of strings

    Example:
        ```python
        import screen_brightness_control as sbc
        monitor_names = sbc.list_monitors()
        # eg: ['BenQ GL2450H', 'Dell U2211H']
        ```
    '''
    return [i['name'] for i in list_monitors_info(method=method)]


class EDID:
    '''
    Simple structure and method to extract monitor serial and name from an EDID string.

    The EDID parsing was created with inspiration from the [pyedid library](https://github.com/jojonas/pyedid)
    '''
    EDID_FORMAT: str = (
        ">"     # big-endian
        "8s"    # constant header (8 bytes)
        "H"     # manufacturer id (2 bytes)
        "H"     # product id (2 bytes)
        "I"     # serial number (4 bytes)
        "B"     # manufactoring week (1 byte)
        "B"     # manufactoring year (1 byte)
        "B"     # edid version (1 byte)
        "B"     # edid revision (1 byte)
        "B"     # video input type (1 byte)
        "B"     # horizontal size in cm (1 byte)
        "B"     # vertical size in cm (1 byte)
        "B"     # display gamma (1 byte)
        "B"     # supported features (1 byte)
        "10s"   # color characteristics (10 bytes)
        "H"     # supported timings (2 bytes)
        "B"     # reserved timing (1 byte)
        "16s"   # EDID supported timings (16 bytes)
        "18s"   # detailed timing block 1 (18 bytes)
        "18s"   # detailed timing block 2 (18 bytes)
        "18s"   # detailed timing block 3 (18 bytes)
        "18s"   # detailed timing block 4 (18 bytes)
        "B"     # extension flag (1 byte)
        "B"     # checksum (1 byte)
    )
    '''The byte structure for EDID strings'''

    @classmethod
    def parse_edid(cls, edid: str) -> Tuple[Union[str, None], str]:
        '''
        Takes an EDID string (as string hex, formatted as: '00ffffff00...') and
        attempts to extract the monitor's name and serial number from it

        Args:
            edid (str): the edid string

        Returns:
            tuple: First item can be None or str. Second item is always str.
                This represents the name and serial respectively.
                If the name (first item) is None then this function likely
                failed to extract the serial correctly.

        Example:
            ```python
            import screen_brightness_control as sbc

            edid = sbc.list_monitors_info()[0]['edid']
            name, serial = sbc.EDID.parse_edid(edid)
            if name is not None:
                print('Success!')
                print('Name:', name)
                print('Serial:', serial)
            else:
                print('Unable to extract the data')
            ```
        '''
        def filter_hex(st):
            st = str(st)
            while '\\x' in st:
                i = st.index('\\x')
                st = st.replace(st[i:i + 4], '')
            return st.replace('\\n', '')[2:-1]

        if ' ' in edid:
            edid = edid.replace(' ', '')
        edid = bytes.fromhex(edid)
        data = struct.unpack(cls.EDID_FORMAT, edid)
        serial = filter_hex(data[18])
        # other info can be anywhere in this range, I don't know why
        name = None
        for i in data[19:22]:
            try:
                st = str(i)[2:-1].rstrip(' ').rstrip('\t')
                if st.index(' ') < len(st) - 1:
                    name = filter_hex(i).split(' ')
                    name = name[0].lower().capitalize() + ' ' + name[1]
            except Exception:
                pass
        return name, serial.strip(' ')

    @staticmethod
    def hexdump(file: str) -> str:
        '''
        Returns a hexadecimal string of binary data from a file

        Args:
            file (str): the file to read

        Returns:
            str: one long hex string

        Example:
            ```python
            from screen_brightness_control import EDID

            print(EDID.hexdump('/sys/class/backlight/intel_backlight/device/edid'))
            # '00ffffffffffff00...'
            ```
        '''
        hex_str = ''
        with open(file, 'rb') as f:
            for char in f.read():
                if char < 16:
                    # hex values less than 16 get represented as single char
                    # eg: 15 -> 'f' instead of '0f'
                    hex_str += '0'
                hex_str += f'{char:x}'  # represent binary as hex string

        return hex_str


MONITOR_MANUFACTURER_CODES = {
    "AAC": "AcerView",
    "ACR": "Acer",
    "AOC": "AOC",
    "AIC": "AG Neovo",
    "APP": "Apple Computer",
    "AST": "AST Research",
    "AUO": "Asus",
    "BNQ": "BenQ",
    "CMO": "Acer",
    "CPL": "Compal",
    "CPQ": "Compaq",
    "CPT": "Chunghwa Pciture Tubes, Ltd.",
    "CTX": "CTX",
    "DEC": "DEC",
    "DEL": "Dell",
    "DPC": "Delta",
    "DWE": "Daewoo",
    "EIZ": "EIZO",
    "ELS": "ELSA",
    "ENC": "EIZO",
    "EPI": "Envision",
    "FCM": "Funai",
    "FUJ": "Fujitsu",
    "FUS": "Fujitsu-Siemens",
    "GSM": "LG Electronics",
    "GWY": "Gateway 2000",
    "HEI": "Hyundai",
    "HIT": "Hyundai",
    "HSL": "Hansol",
    "HTC": "Hitachi/Nissei",
    "HWP": "HP",
    "IBM": "IBM",
    "ICL": "Fujitsu ICL",
    "IVM": "Iiyama",
    "KDS": "Korea Data Systems",
    "LEN": "Lenovo",
    "LGD": "Asus",
    "LPL": "Fujitsu",
    "MAX": "Belinea",
    "MEI": "Panasonic",
    "MEL": "Mitsubishi Electronics",
    "MS_": "Panasonic",
    "NAN": "Nanao",
    "NEC": "NEC",
    "NOK": "Nokia Data",
    "NVD": "Fujitsu",
    "OPT": "Optoma",
    "PHL": "Philips",
    "REL": "Relisys",
    "SAN": "Samsung",
    "SAM": "Samsung",
    "SBI": "Smarttech",
    "SGI": "SGI",
    "SNY": "Sony",
    "SRC": "Shamrock",
    "SUN": "Sun Microsystems",
    "SEC": "Hewlett-Packard",
    "TAT": "Tatung",
    "TOS": "Toshiba",
    "TSB": "Toshiba",
    "VSC": "ViewSonic",
    "ZCM": "Zenith",
    "UNK": "Unknown",
    "_YV": "Fujitsu",
}


@lru_cache(maxsize=None)
def _monitor_brand_lookup(search: str) -> Union[Tuple[str, str], None]:
    '''internal function to search the monitor manufacturer codes dict'''
    keys = tuple(MONITOR_MANUFACTURER_CODES.keys())
    keys_lower = tuple(map(str.lower, keys))
    values = tuple(MONITOR_MANUFACTURER_CODES.values())
    search = search.lower()

    if search in keys_lower:
        index = keys_lower.index(search)
    else:
        values_lower = tuple(map(str.lower, values))
        if search in values_lower:
            index = values_lower.index(search)
        else:
            return None
    return keys[index], values[index]


class ScreenBrightnessError(Exception):
    '''
    Generic error class designed to make catching errors under one umbrella easy.
    Raised when the brightness cannot be set/retrieved.

    Example:
        ```python
        import screen_brightness_control as sbc
        try:
            sbc.set_brightness(50)
        except sbc.ScreenBrightnessError as error:
            print(error)
        ```
    '''
    def __init__(self, message="Cannot set/retrieve brightness level"):
        self.message = message
        super().__init__(self.message)


class Monitor():
    '''A class to manage a single monitor and its relevant information'''
    def __init__(self, display: Union[int, str, dict]):
        '''
        Args:
            display (int or str or dict): the index/name/model name/serial/edid
                of the display you wish to control. Is passed to `filter_monitors`
                to decide which display to use.

        Raises:
            LookupError: if a matching display could not be found
            TypeError: if the given display type is not int or str

        Example:
            ```python
            import screen_brightness_control as sbc

            # create a class for the primary monitor and then a specifically named monitor
            primary = sbc.Monitor(0)
            benq_monitor = sbc.Monitor('BenQ GL2450H')

            # check if the benq monitor is the primary one
            if primary.serial == benq_monitor.serial:
                print('BenQ GL2450H is the primary display')
            else:
                print('The primary display is', primary.name)

            # this class can also be accessed like a dictionary
            print(primary['name'])
            print(benq_monitor['name'])
            ```
        '''
        monitors_info = list_monitors_info(allow_duplicates=True)
        if isinstance(display, dict):
            if display in monitors_info:
                info = display
            else:
                info = filter_monitors(
                    display=self.get_identifier(display),
                    haystack=monitors_info
                )[0]
        else:
            info = filter_monitors(display=display, haystack=monitors_info)[0]

        # make a copy so that we don't alter the dict in-place
        info = info.copy()

        self.serial: str = info.pop('serial')
        '''the serial number of the display or (if serial is not available) an ID assigned by the OS'''
        self.name: str = info.pop('name')
        '''the monitors manufacturer name plus its model'''
        self.method = info.pop('method')
        '''the method by which this monitor can be addressed.
        This will be a class from either the windows or linux sub-module'''
        self.manufacturer: str = info.pop('manufacturer')
        '''the name of the brand of the monitor'''
        self.manufacturer_id: str = info.pop('manufacturer_id')
        '''the 3 letter manufacturing code corresponding to the manufacturer name'''
        self.model: str = info.pop('model')
        '''the general model of the display'''
        self.index: int = info.pop('index')
        '''the index of the monitor FOR THE SPECIFIC METHOD THIS MONITOR USES.'''
        self.edid: str = info.pop('edid')
        '''a unique string returned by the monitor that contains its DDC capabilities, serial and name'''

        # this assigns any extra info that is returned to this class
        # eg: the 'interface' key in XRandr monitors on Linux
        for key, value in info.items():
            if value is not None:
                setattr(self, key, value)

    def __getitem__(self, item: Any) -> Any:
        return getattr(self, item)

    def get_identifier(self, monitor: dict = None) -> Tuple[str, Union[int, str]]:
        '''
        Returns the piece of information used to identify this monitor.
        Will iterate through the EDID, serial, name and index and return the first
        value that is not equal to None

        Args:
            monitor (dict): extract an identifier from this dict instead of the monitor class

        Returns:
            tuple: the name of the property returned and the value of said property.
                EG: `('serial', '123abc...')` or `('name', 'BenQ GL2450H')`

        Example:
            ```python
            import screen_brightness_control as sbc
            primary = sbc.Monitor(0)
            print(primary.get_identifier())  # eg: ('serial', '123abc...')

            secondary = sbc.list_monitors_info()[1]
            print(primary.get_identifier(monitor=secondary))  # eg: ('serial', '456def...')

            # you can also use the class uninitialized
            print(sbc.Monitor.get_identifier(secondary))  # eg: ('serial', '456def...')
            ```
        '''
        if monitor is None:
            monitor = self

        for key in ('edid', 'serial', 'name', 'index'):
            value = monitor[key]
            if value is not None:
                return key, value

    def set_brightness(self, value: int, no_return: bool = True) -> Union[None, int]:
        '''
        Sets the brightness for this display. See `set_brightness` for the full docs

        Args:
            value (int): the brightness value to set the display to (from 0 to 100)
            no_return (bool): if true, this function returns `None`
                Otherwise it returns the result of `Monitor.get_brightness`

        Returns:
            None: if `no_return==True`
            int: from 0 to 100

        Example:
            ```python
            import screen_brightness_control as sbc

            # set the brightness of the primary monitor to 50%
            primary = sbc.Monitor(0)
            primary.set_brightness(50)
            ```
        '''
        # refresh display info, in case another display has been unplugged or something
        # which would change the index of this display
        self.get_info()
        value = max(0, min(value, 100))
        self.method.set_brightness(value, display=self.index)
        if no_return:
            return None
        return self.get_brightness()

    def get_brightness(self) -> int:
        '''
        Returns the brightness of this display.

        Returns:
            int: from 0 to 100

        Example:
            ```python
            import screen_brightness_control as sbc

            # get the brightness of the primary monitor
            primary = sbc.Monitor(0)
            primary_brightness = primary.get_brightness()
            ```
        '''
        # refresh display info, in case another display has been unplugged or something
        # which would change the index of this display
        self.get_info()
        return self.method.get_brightness(display=self.index)[0]

    def fade_brightness(self, *args, **kwargs) -> Union[threading.Thread, int]:
        '''
        Fades the brightness for this display. See `fade_brightness` for the full docs

        Args:
            args (tuple): passed directly to `fade_brightness`
            kwargs (dict): passed directly to `fade_brightness`.
                The `display` and `method` kwargs are always
                overwritten.

        Returns:
            threading.Thread: if the the blocking kwarg is False
            int: if the blocking kwarg is True

        Example:
            ```python
            import screen_brightness_control as sbc

            # fade the brightness of the primary monitor to 50%
            primary = sbc.Monitor(0)
            primary.fade_brightness(50)
            ```
        '''
        # refresh display info, in case another display has been unplugged or something
        # which would change the index of this display
        self.get_info(refresh=False)
        kwargs['display'] = self.index
        # the reason we override the method kwarg here is that
        # the 'index' is method specific and `fade_brightness`
        # is a top-level function. `self.set_brightness` and `self.get_brightness`
        # call directly to the method so they don't need this step
        kwargs['method'] = self.method.__name__.lower()

        brightness = fade_brightness(*args, **kwargs)
        # fade_brightness will call the top-level get_brightness
        # function, which will return list OR int
        if isinstance(brightness, list):
            return brightness[0]
        return brightness

    def get_info(self, refresh: bool = True) -> dict:
        '''
        Returns all known information about this monitor instance

        Args:
            refresh (bool): whether to refresh the information
                or to return the cached version

        Returns:
            dict

        Example:
            ```python
            import screen_brightness_control as sbc

            # initialize class for primary monitor
            primary = sbc.Monitor(0)
            # get the info
            info = primary.get_info()
            ```
        '''
        if not refresh:
            return vars(self)

        identifier = self.get_identifier()

        if identifier is not None:
            # refresh the info we have on this monitor
            info = filter_monitors(display=identifier[1], method=self.method.__name__)[0]
            for key, value in info.items():
                if value is not None:
                    setattr(self, key, value)

        return vars(self)

    def is_active(self) -> bool:
        '''
        Attempts to retrieve the brightness for this display. If it works the display is deemed active

        Returns:
            bool: True means active, False means inactive

        Example:
            ```python
            import screen_brightness_control as sbc

            primary = sbc.Monitor(0)
            if primary.is_active():
                primary.set_brightness(50)
            ```
        '''
        try:
            self.get_brightness()
            return True
        except Exception:
            return False


def filter_monitors(
    display: Optional[Union[int, str]] = None,
    haystack: Optional[List[dict]] = None,
    method: Optional[str] = None,
    include: List[str] = []
) -> List[dict]:
    '''
    Searches through the information for all detected displays
    and attempts to return the info matching the value given.
    Will attempt to match against index, name, model, edid, method and serial

    Args:
        display (str or int): the display you are searching for.
            Can be serial, name, model number, edid string or index of the display
        haystack (list): the information to filter from.
            If this isn't set it defaults to the return of `list_monitors_info`
        method (str): the method the monitors use
        include (list): extra fields of information to sort by

    Raises:
        TypeError: if the display kwarg is not an int, str or None
        LookupError: if the display, does not have a match

    Returns:
        list: list of dicts

    Example:
        ```python
        import screen_brightness_control as sbc

        search = 'GL2450H'
        match = sbc.filter_displays(search)
        print(match)
        # EG output: [{'name': 'BenQ GL2450H', 'model': 'GL2450H', ... }]
        ```
    '''
    # if we have been provided with a list of monitors to sift through then use that
    # otherwise, get the info ourselves
    if haystack:
        monitors_with_duplicates = haystack
        if method is not None:
            monitors_with_duplicates = [i for i in haystack if method.lower() == i['method'].__name__.lower()]
    else:
        monitors_with_duplicates = list_monitors_info(method=method, allow_duplicates=True)

    if display is not None and type(display) not in (str, int):
        raise TypeError(f'display kwarg must be int or str, not "{type(display).__name__}"')

    # This loop does two things: 1. Filters out duplicate monitors and 2. Matches the display kwarg (if applicable)
    unique_identifiers = []
    monitors = []
    for monitor in monitors_with_duplicates:
        # find a valid identifier for a monitor, excluding any which are equal to None
        added = False
        for identifier in ['edid', 'serial', 'name', 'model'] + include:
            if monitor.get(identifier, None) is not None:
                # check we haven't already added the monitor
                if monitor[identifier] not in unique_identifiers:
                    # check if the display kwarg (if str) matches this monitor
                    if monitor[identifier] == display or not isinstance(display, str):
                        # if valid and monitor[identifier] not in unique_identifiers:
                        if not added:
                            monitors.append(monitor)
                            unique_identifiers.append(monitor[identifier])
                            added = True

                        # if the display kwarg is an integer and we are currently at that index
                        if isinstance(display, int) and len(monitors) - 1 == display:
                            return [monitor]
                        if added:
                            break
                else:
                    # if we have already added a monitor with the same identifier
                    # then any info matching this monitor will match the other one
                    # so exit the checking now
                    break

    # if no monitors matched the query OR if display kwarg was an int
    # if the latter and we made it this far then the int was out of range
    if monitors == [] or isinstance(display, int):
        msg = 'no monitors found'
        if display is not None:
            msg += f' with name/serial/model/edid/index of {repr(display)}'
        if method is not None:
            msg += f' with method of "{method}"'
        raise LookupError(msg)

    return monitors


def flatten_list(thick_list: List[Any]) -> List[Any]:
    '''
    Internal function I use to flatten lists, because I do that often

    Args:
        thick_list (list): The list to be flattened. Can be as deep as you wish (within recursion limits)

    Returns:
        list: one dimensional

    Example:
        ```python
        import screen_brightness_control as sbc
        thick_list = [1, [2, [3, 4, 5], 6, 7], 8, [9, 10]]
        flat_list = sbc.flatten_list(thick_list)
        # Output: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
        ```
    '''
    flat_list = []
    for item in thick_list:
        if isinstance(item, list):
            flat_list += flatten_list(item)
        else:
            flat_list.append(item)
    return flat_list


def __brightness(
    *args, display=None, method=None, meta_method='get', no_return=False,
    verbose_error=False, **kwargs
):
    '''Internal function used to get/set brightness'''

    def format_exc(name, e):
        errors.append((
            name, e.__class__.__name__,
            traceback.format_exc() if verbose_error else e
        ))

    output = []
    errors = []
    method = method.lower() if isinstance(method, str) else method

    try:
        monitors = filter_monitors(display=display, method=method)
    except (LookupError, ValueError) as e:
        if platform.system() == 'Linux' and display is None and method in ('xbacklight', None):
            try:
                if meta_method == 'set':
                    _OS_MODULE.XBacklight.set_brightness(*args)
                output.append(_OS_MODULE.XBacklight.get_brightness())
            except Exception as e:
                format_exc('XBacklight', e)
        else:
            format_exc('filter_monitors', e)
    except Exception as e:
        format_exc('filter_monitors', e)
    else:
        for monitor in monitors:
            try:
                if meta_method == 'set':
                    monitor['method'].set_brightness(*args, display=monitor['index'], **kwargs)
                    if no_return:
                        output.append(None)
                        continue

                output.append(monitor['method'].get_brightness(display=monitor['index'], **kwargs))
            except Exception as e:
                output.append(None)
                format_exc(monitor, e)

    output = flatten_list(output)

    if output:
        output_is_none = set(output) == {None}
        if (
            # can't have None output if we are trying to get the brightness
            (meta_method == 'get' and not output_is_none)
            or (
                # if we are setting the brightness then we CAN have a None output
                # but only if no_return is True.
                meta_method == 'set'
                and ((no_return and output_is_none) or not output_is_none)
            )
        ):
            return None if no_return else output

    # if the function hasn't returned then it has failed
    msg = '\n'
    if errors:
        for monitor, exc_name, exc in errors:
            if isinstance(monitor, str):
                msg += f'\t{monitor}'
            else:
                msg += f'\t{monitor["name"]} ({monitor["serial"]})'
            msg += f' -> {exc_name}: '
            msg += str(exc).replace('\n', '\n\t\t') + '\n'
    else:
        msg += '\tno valid output was received from brightness methods'

    raise ScreenBrightnessError(msg)


class __Cache(dict):
    '''class to cache data with a short shelf life'''
    def __init__(self):
        self.enabled = True
        super().__init__()

    def get(self, key, *args, **kwargs):
        if not self.enabled:
            return None

        try:
            value, expires, orig_args, orig_kwargs = self[key]
            if time.time() < expires:
                if orig_args == args and orig_kwargs == kwargs:
                    return value
            else:
                del self[key]
        except KeyError:
            pass

    def store(self, key, value, *args, expires=1, **kwargs):
        self[key] = (value, expires + time.time(), args, kwargs)

    def expire(self, key=None, startswith=None):
        if key is not None:
            try:
                del self[key]
            except KeyError:
                pass
        elif startswith is not None:
            for i in tuple(self.keys()):
                if i.startswith(startswith):
                    del self[i]


__cache__ = __Cache()

if platform.system() == 'Windows':
    from . import windows
    _OS_MODULE = windows
elif platform.system() == 'Linux':
    from . import linux
    _OS_MODULE = linux
elif platform.system() == 'Darwin':
    raise NotImplementedError('MAC is not yet supported')
else:
    raise NotImplementedError(f'{platform.system()} is not yet supported')
#   def get_brightness( display: Union[str, int, NoneType] = None, method: Optional[str] = None, verbose_error: bool = False ) -> List[int]:
View Source
def get_brightness(
    display: Optional[Union[int, str]] = None,
    method: Optional[str] = None,
    verbose_error: bool = False
) -> List[int]:
    '''
    Returns the current display brightness

    Args:
        display (str or int): the specific display to query
        method (str): the way in which displays will be accessed.
            On Windows this can be 'wmi' or 'vcp'.
            On Linux it's 'light', 'xrandr', 'ddcutil' or 'xbacklight'.
        verbose_error (bool): controls the level of detail in the error messages

    Returns:
        list: a list of integers (from 0 to 100), each integer being the
            percentage brightness of a display (invalid displays may return None)

    Example:
        ```python
        import screen_brightness_control as sbc

        # get the current screen brightness (for all detected displays)
        current_brightness = sbc.get_brightness()

        # get the brightness of the primary display
        primary_brightness = sbc.get_brightness(display=0)

        # get the brightness of the secondary display (if connected)
        secondary_brightness = sbc.get_brightness(display=1)
        ```
    '''
    return __brightness(display=display, method=method, meta_method='get', verbose_error=verbose_error)

Returns the current display brightness

Args
  • display (str or int): the specific display to query
  • method (str): the way in which displays will be accessed. On Windows this can be 'wmi' or 'vcp'. On Linux it's 'light', 'xrandr', 'ddcutil' or 'xbacklight'.
  • verbose_error (bool): controls the level of detail in the error messages
Returns
  • list: a list of integers (from 0 to 100), each integer being the percentage brightness of a display (invalid displays may return None)
Example
import screen_brightness_control as sbc

# get the current screen brightness (for all detected displays)
current_brightness = sbc.get_brightness()

# get the brightness of the primary display
primary_brightness = sbc.get_brightness(display=0)

# get the brightness of the secondary display (if connected)
secondary_brightness = sbc.get_brightness(display=1)
#   def set_brightness( value: Union[int, float, str], display: Union[str, int, NoneType] = None, method: Optional[str] = None, force: bool = False, verbose_error: bool = False, no_return: bool = True ) -> Optional[List[int]]:
View Source
def set_brightness(
    value: Union[int, float, str],
    display: Optional[Union[str, int]] = None,
    method: Optional[str] = None,
    force: bool = False,
    verbose_error: bool = False,
    no_return: bool = True
) -> Union[None, List[int]]:
    '''
    Sets the screen brightness

    Args:
        value (int or float or str): a value 0 to 100. This is a percentage or a string as '+5' or '-5'
        display (int or str): the specific display to adjust
        method (str): the way in which displays will be accessed.
            On Windows this can be 'wmi' or 'vcp'.
            On Linux it's 'light', 'xrandr', 'ddcutil' or 'xbacklight'.
        force (bool): [*Linux Only*] if False the brightness will never be set lower than 1.
            This is because on most displays a brightness of 0 will turn off the backlight.
            If True, this check is bypassed
        verbose_error (bool): boolean value controls the amount of detail error messages will contain
        no_return (bool): if False, this function returns new brightness (by calling `get_brightness`).
            If True, this function returns None (default behaviour).

    Returns:
        None: if the `no_return` kwarg is `True`
        list: a list of integers (from 0 to 100), each integer being the
            percentage brightness of a display (invalid displays may return None)

    Example:
        ```python
        import screen_brightness_control as sbc

        # set brightness to 50%
        sbc.set_brightness(50)

        # set brightness to 0%
        sbc.set_brightness(0, force=True)

        # increase brightness by 25%
        sbc.set_brightness('+25')

        # decrease brightness by 30%
        sbc.set_brightness('-30')

        # set the brightness of display 0 to 50%
        sbc.set_brightness(50, display=0)
        ```
    '''
    if isinstance(value, str) and ('+' in value or '-' in value):
        value = int(float(value))
        monitors = filter_monitors(display=display, method=method)
        if len(monitors) > 1:
            output = []
            for monitor in monitors:
                identifier = Monitor.get_identifier(monitor)[1]
                output.append(
                    set_brightness(
                        get_brightness(display=identifier)[0] + value,
                        display=identifier,
                        force=force,
                        verbose_error=verbose_error,
                        no_return=no_return
                    )
                )
            return flatten_list(output)

        value += get_brightness(display=Monitor.get_identifier(monitors[0])[1])[0]
    else:
        value = int(float(str(value)))

    # make sure value is within bounds
    value = max(min(100, value), 0)

    if platform.system() == 'Linux' and not force:
        value = max(1, value)

    return __brightness(
        value, display=display, method=method,
        meta_method='set', no_return=no_return,
        verbose_error=verbose_error
    )

Sets the screen brightness

Args
  • value (int or float or str): a value 0 to 100. This is a percentage or a string as '+5' or '-5'
  • display (int or str): the specific display to adjust
  • method (str): the way in which displays will be accessed. On Windows this can be 'wmi' or 'vcp'. On Linux it's 'light', 'xrandr', 'ddcutil' or 'xbacklight'.
  • force (bool): [Linux Only] if False the brightness will never be set lower than 1. This is because on most displays a brightness of 0 will turn off the backlight. If True, this check is bypassed
  • verbose_error (bool): boolean value controls the amount of detail error messages will contain
  • no_return (bool): if False, this function returns new brightness (by calling get_brightness). If True, this function returns None (default behaviour).
Returns
  • None: if the no_return kwarg is True
  • list: a list of integers (from 0 to 100), each integer being the percentage brightness of a display (invalid displays may return None)
Example
import screen_brightness_control as sbc

# set brightness to 50%
sbc.set_brightness(50)

# set brightness to 0%
sbc.set_brightness(0, force=True)

# increase brightness by 25%
sbc.set_brightness('+25')

# decrease brightness by 30%
sbc.set_brightness('-30')

# set the brightness of display 0 to 50%
sbc.set_brightness(50, display=0)
#   def fade_brightness( finish: Union[int, str], start: Union[str, int, NoneType] = None, interval: float = 0.01, increment: int = 1, blocking: bool = True, **kwargs ) -> Union[List[threading.Thread], List[int]]:
View Source
def fade_brightness(
    finish: Union[int, str],
    start: Optional[Union[int, str]] = None,
    interval: float = 0.01,
    increment: int = 1,
    blocking: bool = True,
    **kwargs
) -> Union[List[threading.Thread], List[int]]:
    '''
    A function to somewhat gently fade the screen brightness from `start` to `finish`

    Args:
        finish (int or str): the brightness level to end up on
        start (int or str): where the brightness should fade from.
            If not specified the function starts from the current screen brightness
        interval (float or int): the time delay between each step in brightness
        increment (int): the amount to change the brightness by per step
        blocking (bool): whether this should occur in the main thread (`True`) or a new daemonic thread (`False`)
        kwargs (dict): passed directly to `set_brightness`.
            Any compatible kwargs are passed to `filter_monitors` as well. (eg: display, method...)

    Returns:
        list: list of `threading.Thread` objects if `blocking == False`,
            otherwise it returns the result of `get_brightness()`

    Example:
        ```python
        import screen_brightness_control as sbc

        # fade brightness from the current brightness to 50%
        sbc.fade_brightness(50)

        # fade the brightness from 25% to 75%
        sbc.fade_brightness(75, start=25)

        # fade the brightness from the current value to 100% in steps of 10%
        sbc.fade_brightness(100, increment=10)

        # fade the brightness from 100% to 90% with time intervals of 0.1 seconds
        sbc.fade_brightness(90, start=100, interval=0.1)

        # fade the brightness to 100% in a new thread
        sbc.fade_brightness(100, blocking=False)
        ```
    '''
    def fade(start, finish, increment, monitor):
        for i in range(min(start, finish), max(start, finish), increment):
            val = i
            if start > finish:
                val = start - (val - finish)
            monitor.set_brightness(val, no_return=True)
            time.sleep(interval)

        if monitor.get_brightness() != finish:
            monitor.set_brightness(finish, no_return=True)

    def err_msg(e):
        return f'\n\tfilter_monitors -> {type(e).__name__}: {e}'

    try:
        # make sure only compatible kwargs are passed to filter_monitors
        available_monitors = filter_monitors(
            **{k: v for k, v in kwargs.items() if k in (
                'display', 'haystack', 'method', 'include'
            )}
        )
    except (LookupError, ValueError) as e:
        if not platform.system() == 'Linux':
            raise ScreenBrightnessError(err_msg(e)) from e

        method = kwargs.get('method', None)
        if isinstance(e, LookupError) and method is None:
            # if a user ONLY has XBacklight installed and no method was specified
            # then filter_monitors will raise a LookupError. In this case, default to using
            # linux.XBacklight method
            available_monitors = [_OS_MODULE.XBacklight]
        elif isinstance(e, ValueError) and method.lower() == 'xbacklight':
            # low level `list_monitors_info` will raise a ValueError if 'xbacklight' is passed as the method
            # because xbacklight cannot query individual monitor information
            available_monitors = [_OS_MODULE.XBacklight]
        else:
            raise ScreenBrightnessError(err_msg(e)) from e

    except Exception as e:
        raise ScreenBrightnessError(err_msg(e)) from e

    threads = []
    for i in available_monitors:
        try:
            if platform.system() == 'Linux' and i == _OS_MODULE.XBacklight:
                monitor = i
            else:
                monitor = Monitor(i)

            # same effect as monitor.is_active()
            current = monitor.get_brightness()
            st, fi = start, finish
            # convert strings like '+5' to an actual brightness value
            if isinstance(fi, str):
                if "+" in fi or "-" in fi:
                    fi = current + int(float(fi))
            if isinstance(st, str):
                if "+" in st or "-" in st:
                    st = current + int(float(st))

            st = current if st is None else st
            # make sure both values are within the correct range
            fi = min(max(int(float(fi)), 0), 100)
            st = min(max(int(float(st)), 0), 100)

            t1 = threading.Thread(target=fade, args=(st, fi, increment, monitor))
            t1.start()
            threads.append(t1)
        except Exception:
            pass

    if not blocking:
        return threads

    for t in threads:
        t.join()
    return get_brightness(**kwargs)

A function to somewhat gently fade the screen brightness from start to finish

Args
  • finish (int or str): the brightness level to end up on
  • start (int or str): where the brightness should fade from. If not specified the function starts from the current screen brightness
  • interval (float or int): the time delay between each step in brightness
  • increment (int): the amount to change the brightness by per step
  • blocking (bool): whether this should occur in the main thread (True) or a new daemonic thread (False)
  • kwargs (dict): passed directly to set_brightness. Any compatible kwargs are passed to filter_monitors as well. (eg: display, method...)
Returns
  • list: list of threading.Thread objects if blocking == False, otherwise it returns the result of get_brightness()
Example
import screen_brightness_control as sbc

# fade brightness from the current brightness to 50%
sbc.fade_brightness(50)

# fade the brightness from 25% to 75%
sbc.fade_brightness(75, start=25)

# fade the brightness from the current value to 100% in steps of 10%
sbc.fade_brightness(100, increment=10)

# fade the brightness from 100% to 90% with time intervals of 0.1 seconds
sbc.fade_brightness(90, start=100, interval=0.1)

# fade the brightness to 100% in a new thread
sbc.fade_brightness(100, blocking=False)
#   def list_monitors_info( method: Optional[str] = None, allow_duplicates: bool = False ) -> List[dict]:
View Source
def list_monitors_info(method: Optional[str] = None, allow_duplicates: bool = False) -> List[dict]:
    '''
    list detailed information about all monitors that are controllable by this library

    Args:
        method (str): the method to use to list the available monitors.
            On Windows this can be `'wmi'` or `'vcp'`.
            On Linux this can be `'light'`, `'xrandr'`, `'ddcutil'` or `'sysfiles'`.
        allow_duplicates (bool): whether to filter out duplicate displays or not

    Returns:
        list: list of dictionaries

    Example:
        ```python
        import screen_brightness_control as sbc
        monitors = sbc.list_monitors_info()
        for monitor in monitors:
            print('=======================')
            # the manufacturer name plus the model
            print('Name:', monitor['name'])
            # the general model of the display
            print('Model:', monitor['model'])
            # the serial of the display
            print('Serial:', monitor['serial'])
            # the name of the brand of the monitor
            print('Manufacturer:', monitor['manufacturer'])
            # the 3 letter code corresponding to the brand name, EG: BNQ -> BenQ
            print('Manufacturer ID:', monitor['manufacturer_id'])
            # the index of that display FOR THE SPECIFIC METHOD THE DISPLAY USES
            print('Index:', monitor['index'])
            # the method this monitor can be addressed by
            print('Method:', monitor['method'])
            # the EDID string associated with that monitor
            print('EDID:', monitor['edid'])
        ```
    '''
    info = __cache__.get('monitors_info', method=method, allow_duplicates=allow_duplicates)
    if info is None:
        info = _OS_MODULE.list_monitors_info(method=method, allow_duplicates=allow_duplicates)
        __cache__.store('monitors_info', info, method=method, allow_duplicates=allow_duplicates)
    return info

list detailed information about all monitors that are controllable by this library

Args
  • method (str): the method to use to list the available monitors. On Windows this can be 'wmi' or 'vcp'. On Linux this can be 'light', 'xrandr', 'ddcutil' or 'sysfiles'.
  • allow_duplicates (bool): whether to filter out duplicate displays or not
Returns
  • list: list of dictionaries
Example
import screen_brightness_control as sbc
monitors = sbc.list_monitors_info()
for monitor in monitors:
    print('=======================')
    # the manufacturer name plus the model
    print('Name:', monitor['name'])
    # the general model of the display
    print('Model:', monitor['model'])
    # the serial of the display
    print('Serial:', monitor['serial'])
    # the name of the brand of the monitor
    print('Manufacturer:', monitor['manufacturer'])
    # the 3 letter code corresponding to the brand name, EG: BNQ -> BenQ
    print('Manufacturer ID:', monitor['manufacturer_id'])
    # the index of that display FOR THE SPECIFIC METHOD THE DISPLAY USES
    print('Index:', monitor['index'])
    # the method this monitor can be addressed by
    print('Method:', monitor['method'])
    # the EDID string associated with that monitor
    print('EDID:', monitor['edid'])
#   def list_monitors(method: Optional[str] = None) -> List[str]:
View Source
def list_monitors(method: Optional[str] = None) -> List[str]:
    '''
    List the names of all detected monitors

    Args:
        method (str): the method to use to list the available monitors.
            On Windows this can be `'wmi'` or `'vcp'`.
            On Linux this can be `'light'`, `'xrandr'`, `'ddcutil'` or `'sysfiles'`.

    Returns:
        list: list of strings

    Example:
        ```python
        import screen_brightness_control as sbc
        monitor_names = sbc.list_monitors()
        # eg: ['BenQ GL2450H', 'Dell U2211H']
        ```
    '''
    return [i['name'] for i in list_monitors_info(method=method)]

List the names of all detected monitors

Args
  • method (str): the method to use to list the available monitors. On Windows this can be 'wmi' or 'vcp'. On Linux this can be 'light', 'xrandr', 'ddcutil' or 'sysfiles'.
Returns
  • list: list of strings
Example
import screen_brightness_control as sbc
monitor_names = sbc.list_monitors()
# eg: ['BenQ GL2450H', 'Dell U2211H']
#   class EDID:
View Source
class EDID:
    '''
    Simple structure and method to extract monitor serial and name from an EDID string.

    The EDID parsing was created with inspiration from the [pyedid library](https://github.com/jojonas/pyedid)
    '''
    EDID_FORMAT: str = (
        ">"     # big-endian
        "8s"    # constant header (8 bytes)
        "H"     # manufacturer id (2 bytes)
        "H"     # product id (2 bytes)
        "I"     # serial number (4 bytes)
        "B"     # manufactoring week (1 byte)
        "B"     # manufactoring year (1 byte)
        "B"     # edid version (1 byte)
        "B"     # edid revision (1 byte)
        "B"     # video input type (1 byte)
        "B"     # horizontal size in cm (1 byte)
        "B"     # vertical size in cm (1 byte)
        "B"     # display gamma (1 byte)
        "B"     # supported features (1 byte)
        "10s"   # color characteristics (10 bytes)
        "H"     # supported timings (2 bytes)
        "B"     # reserved timing (1 byte)
        "16s"   # EDID supported timings (16 bytes)
        "18s"   # detailed timing block 1 (18 bytes)
        "18s"   # detailed timing block 2 (18 bytes)
        "18s"   # detailed timing block 3 (18 bytes)
        "18s"   # detailed timing block 4 (18 bytes)
        "B"     # extension flag (1 byte)
        "B"     # checksum (1 byte)
    )
    '''The byte structure for EDID strings'''

    @classmethod
    def parse_edid(cls, edid: str) -> Tuple[Union[str, None], str]:
        '''
        Takes an EDID string (as string hex, formatted as: '00ffffff00...') and
        attempts to extract the monitor's name and serial number from it

        Args:
            edid (str): the edid string

        Returns:
            tuple: First item can be None or str. Second item is always str.
                This represents the name and serial respectively.
                If the name (first item) is None then this function likely
                failed to extract the serial correctly.

        Example:
            ```python
            import screen_brightness_control as sbc

            edid = sbc.list_monitors_info()[0]['edid']
            name, serial = sbc.EDID.parse_edid(edid)
            if name is not None:
                print('Success!')
                print('Name:', name)
                print('Serial:', serial)
            else:
                print('Unable to extract the data')
            ```
        '''
        def filter_hex(st):
            st = str(st)
            while '\\x' in st:
                i = st.index('\\x')
                st = st.replace(st[i:i + 4], '')
            return st.replace('\\n', '')[2:-1]

        if ' ' in edid:
            edid = edid.replace(' ', '')
        edid = bytes.fromhex(edid)
        data = struct.unpack(cls.EDID_FORMAT, edid)
        serial = filter_hex(data[18])
        # other info can be anywhere in this range, I don't know why
        name = None
        for i in data[19:22]:
            try:
                st = str(i)[2:-1].rstrip(' ').rstrip('\t')
                if st.index(' ') < len(st) - 1:
                    name = filter_hex(i).split(' ')
                    name = name[0].lower().capitalize() + ' ' + name[1]
            except Exception:
                pass
        return name, serial.strip(' ')

    @staticmethod
    def hexdump(file: str) -> str:
        '''
        Returns a hexadecimal string of binary data from a file

        Args:
            file (str): the file to read

        Returns:
            str: one long hex string

        Example:
            ```python
            from screen_brightness_control import EDID

            print(EDID.hexdump('/sys/class/backlight/intel_backlight/device/edid'))
            # '00ffffffffffff00...'
            ```
        '''
        hex_str = ''
        with open(file, 'rb') as f:
            for char in f.read():
                if char < 16:
                    # hex values less than 16 get represented as single char
                    # eg: 15 -> 'f' instead of '0f'
                    hex_str += '0'
                hex_str += f'{char:x}'  # represent binary as hex string

        return hex_str

Simple structure and method to extract monitor serial and name from an EDID string.

The EDID parsing was created with inspiration from the pyedid library

#   EDID()
#   EDID_FORMAT: str = '>8sHHIBBBBBBBBB10sHB16s18s18s18s18sBB'

The byte structure for EDID strings

#  
@classmethod
def parse_edid(cls, edid: str) -> Tuple[Optional[str], str]:
View Source
    @classmethod
    def parse_edid(cls, edid: str) -> Tuple[Union[str, None], str]:
        '''
        Takes an EDID string (as string hex, formatted as: '00ffffff00...') and
        attempts to extract the monitor's name and serial number from it

        Args:
            edid (str): the edid string

        Returns:
            tuple: First item can be None or str. Second item is always str.
                This represents the name and serial respectively.
                If the name (first item) is None then this function likely
                failed to extract the serial correctly.

        Example:
            ```python
            import screen_brightness_control as sbc

            edid = sbc.list_monitors_info()[0]['edid']
            name, serial = sbc.EDID.parse_edid(edid)
            if name is not None:
                print('Success!')
                print('Name:', name)
                print('Serial:', serial)
            else:
                print('Unable to extract the data')
            ```
        '''
        def filter_hex(st):
            st = str(st)
            while '\\x' in st:
                i = st.index('\\x')
                st = st.replace(st[i:i + 4], '')
            return st.replace('\\n', '')[2:-1]

        if ' ' in edid:
            edid = edid.replace(' ', '')
        edid = bytes.fromhex(edid)
        data = struct.unpack(cls.EDID_FORMAT, edid)
        serial = filter_hex(data[18])
        # other info can be anywhere in this range, I don't know why
        name = None
        for i in data[19:22]:
            try:
                st = str(i)[2:-1].rstrip(' ').rstrip('\t')
                if st.index(' ') < len(st) - 1:
                    name = filter_hex(i).split(' ')
                    name = name[0].lower().capitalize() + ' ' + name[1]
            except Exception:
                pass
        return name, serial.strip(' ')

Takes an EDID string (as string hex, formatted as: '00ffffff00...') and attempts to extract the monitor's name and serial number from it

Args
  • edid (str): the edid string
Returns
  • tuple: First item can be None or str. Second item is always str. This represents the name and serial respectively. If the name (first item) is None then this function likely failed to extract the serial correctly.
Example
import screen_brightness_control as sbc

edid = sbc.list_monitors_info()[0]['edid']
name, serial = sbc.EDID.parse_edid(edid)
if name is not None:
    print('Success!')
    print('Name:', name)
    print('Serial:', serial)
else:
    print('Unable to extract the data')
#  
@staticmethod
def hexdump(file: str) -> str:
View Source
    @staticmethod
    def hexdump(file: str) -> str:
        '''
        Returns a hexadecimal string of binary data from a file

        Args:
            file (str): the file to read

        Returns:
            str: one long hex string

        Example:
            ```python
            from screen_brightness_control import EDID

            print(EDID.hexdump('/sys/class/backlight/intel_backlight/device/edid'))
            # '00ffffffffffff00...'
            ```
        '''
        hex_str = ''
        with open(file, 'rb') as f:
            for char in f.read():
                if char < 16:
                    # hex values less than 16 get represented as single char
                    # eg: 15 -> 'f' instead of '0f'
                    hex_str += '0'
                hex_str += f'{char:x}'  # represent binary as hex string

        return hex_str

Returns a hexadecimal string of binary data from a file

Args
  • file (str): the file to read
Returns
  • str: one long hex string
Example
from screen_brightness_control import EDID

print(EDID.hexdump('/sys/class/backlight/intel_backlight/device/edid'))
# '00ffffffffffff00...'
#   class ScreenBrightnessError(builtins.Exception):
View Source
class ScreenBrightnessError(Exception):
    '''
    Generic error class designed to make catching errors under one umbrella easy.
    Raised when the brightness cannot be set/retrieved.

    Example:
        ```python
        import screen_brightness_control as sbc
        try:
            sbc.set_brightness(50)
        except sbc.ScreenBrightnessError as error:
            print(error)
        ```
    '''
    def __init__(self, message="Cannot set/retrieve brightness level"):
        self.message = message
        super().__init__(self.message)

Generic error class designed to make catching errors under one umbrella easy. Raised when the brightness cannot be set/retrieved.

Example
import screen_brightness_control as sbc
try:
    sbc.set_brightness(50)
except sbc.ScreenBrightnessError as error:
    print(error)
#   ScreenBrightnessError(message='Cannot set/retrieve brightness level')
View Source
    def __init__(self, message="Cannot set/retrieve brightness level"):
        self.message = message
        super().__init__(self.message)
Inherited Members
builtins.BaseException
with_traceback
args
#   class Monitor:
View Source
class Monitor():
    '''A class to manage a single monitor and its relevant information'''
    def __init__(self, display: Union[int, str, dict]):
        '''
        Args:
            display (int or str or dict): the index/name/model name/serial/edid
                of the display you wish to control. Is passed to `filter_monitors`
                to decide which display to use.

        Raises:
            LookupError: if a matching display could not be found
            TypeError: if the given display type is not int or str

        Example:
            ```python
            import screen_brightness_control as sbc

            # create a class for the primary monitor and then a specifically named monitor
            primary = sbc.Monitor(0)
            benq_monitor = sbc.Monitor('BenQ GL2450H')

            # check if the benq monitor is the primary one
            if primary.serial == benq_monitor.serial:
                print('BenQ GL2450H is the primary display')
            else:
                print('The primary display is', primary.name)

            # this class can also be accessed like a dictionary
            print(primary['name'])
            print(benq_monitor['name'])
            ```
        '''
        monitors_info = list_monitors_info(allow_duplicates=True)
        if isinstance(display, dict):
            if display in monitors_info:
                info = display
            else:
                info = filter_monitors(
                    display=self.get_identifier(display),
                    haystack=monitors_info
                )[0]
        else:
            info = filter_monitors(display=display, haystack=monitors_info)[0]

        # make a copy so that we don't alter the dict in-place
        info = info.copy()

        self.serial: str = info.pop('serial')
        '''the serial number of the display or (if serial is not available) an ID assigned by the OS'''
        self.name: str = info.pop('name')
        '''the monitors manufacturer name plus its model'''
        self.method = info.pop('method')
        '''the method by which this monitor can be addressed.
        This will be a class from either the windows or linux sub-module'''
        self.manufacturer: str = info.pop('manufacturer')
        '''the name of the brand of the monitor'''
        self.manufacturer_id: str = info.pop('manufacturer_id')
        '''the 3 letter manufacturing code corresponding to the manufacturer name'''
        self.model: str = info.pop('model')
        '''the general model of the display'''
        self.index: int = info.pop('index')
        '''the index of the monitor FOR THE SPECIFIC METHOD THIS MONITOR USES.'''
        self.edid: str = info.pop('edid')
        '''a unique string returned by the monitor that contains its DDC capabilities, serial and name'''

        # this assigns any extra info that is returned to this class
        # eg: the 'interface' key in XRandr monitors on Linux
        for key, value in info.items():
            if value is not None:
                setattr(self, key, value)

    def __getitem__(self, item: Any) -> Any:
        return getattr(self, item)

    def get_identifier(self, monitor: dict = None) -> Tuple[str, Union[int, str]]:
        '''
        Returns the piece of information used to identify this monitor.
        Will iterate through the EDID, serial, name and index and return the first
        value that is not equal to None

        Args:
            monitor (dict): extract an identifier from this dict instead of the monitor class

        Returns:
            tuple: the name of the property returned and the value of said property.
                EG: `('serial', '123abc...')` or `('name', 'BenQ GL2450H')`

        Example:
            ```python
            import screen_brightness_control as sbc
            primary = sbc.Monitor(0)
            print(primary.get_identifier())  # eg: ('serial', '123abc...')

            secondary = sbc.list_monitors_info()[1]
            print(primary.get_identifier(monitor=secondary))  # eg: ('serial', '456def...')

            # you can also use the class uninitialized
            print(sbc.Monitor.get_identifier(secondary))  # eg: ('serial', '456def...')
            ```
        '''
        if monitor is None:
            monitor = self

        for key in ('edid', 'serial', 'name', 'index'):
            value = monitor[key]
            if value is not None:
                return key, value

    def set_brightness(self, value: int, no_return: bool = True) -> Union[None, int]:
        '''
        Sets the brightness for this display. See `set_brightness` for the full docs

        Args:
            value (int): the brightness value to set the display to (from 0 to 100)
            no_return (bool): if true, this function returns `None`
                Otherwise it returns the result of `Monitor.get_brightness`

        Returns:
            None: if `no_return==True`
            int: from 0 to 100

        Example:
            ```python
            import screen_brightness_control as sbc

            # set the brightness of the primary monitor to 50%
            primary = sbc.Monitor(0)
            primary.set_brightness(50)
            ```
        '''
        # refresh display info, in case another display has been unplugged or something
        # which would change the index of this display
        self.get_info()
        value = max(0, min(value, 100))
        self.method.set_brightness(value, display=self.index)
        if no_return:
            return None
        return self.get_brightness()

    def get_brightness(self) -> int:
        '''
        Returns the brightness of this display.

        Returns:
            int: from 0 to 100

        Example:
            ```python
            import screen_brightness_control as sbc

            # get the brightness of the primary monitor
            primary = sbc.Monitor(0)
            primary_brightness = primary.get_brightness()
            ```
        '''
        # refresh display info, in case another display has been unplugged or something
        # which would change the index of this display
        self.get_info()
        return self.method.get_brightness(display=self.index)[0]

    def fade_brightness(self, *args, **kwargs) -> Union[threading.Thread, int]:
        '''
        Fades the brightness for this display. See `fade_brightness` for the full docs

        Args:
            args (tuple): passed directly to `fade_brightness`
            kwargs (dict): passed directly to `fade_brightness`.
                The `display` and `method` kwargs are always
                overwritten.

        Returns:
            threading.Thread: if the the blocking kwarg is False
            int: if the blocking kwarg is True

        Example:
            ```python
            import screen_brightness_control as sbc

            # fade the brightness of the primary monitor to 50%
            primary = sbc.Monitor(0)
            primary.fade_brightness(50)
            ```
        '''
        # refresh display info, in case another display has been unplugged or something
        # which would change the index of this display
        self.get_info(refresh=False)
        kwargs['display'] = self.index
        # the reason we override the method kwarg here is that
        # the 'index' is method specific and `fade_brightness`
        # is a top-level function. `self.set_brightness` and `self.get_brightness`
        # call directly to the method so they don't need this step
        kwargs['method'] = self.method.__name__.lower()

        brightness = fade_brightness(*args, **kwargs)
        # fade_brightness will call the top-level get_brightness
        # function, which will return list OR int
        if isinstance(brightness, list):
            return brightness[0]
        return brightness

    def get_info(self, refresh: bool = True) -> dict:
        '''
        Returns all known information about this monitor instance

        Args:
            refresh (bool): whether to refresh the information
                or to return the cached version

        Returns:
            dict

        Example:
            ```python
            import screen_brightness_control as sbc

            # initialize class for primary monitor
            primary = sbc.Monitor(0)
            # get the info
            info = primary.get_info()
            ```
        '''
        if not refresh:
            return vars(self)

        identifier = self.get_identifier()

        if identifier is not None:
            # refresh the info we have on this monitor
            info = filter_monitors(display=identifier[1], method=self.method.__name__)[0]
            for key, value in info.items():
                if value is not None:
                    setattr(self, key, value)

        return vars(self)

    def is_active(self) -> bool:
        '''
        Attempts to retrieve the brightness for this display. If it works the display is deemed active

        Returns:
            bool: True means active, False means inactive

        Example:
            ```python
            import screen_brightness_control as sbc

            primary = sbc.Monitor(0)
            if primary.is_active():
                primary.set_brightness(50)
            ```
        '''
        try:
            self.get_brightness()
            return True
        except Exception:
            return False

A class to manage a single monitor and its relevant information

#   Monitor(display: Union[int, str, dict])
View Source
    def __init__(self, display: Union[int, str, dict]):
        '''
        Args:
            display (int or str or dict): the index/name/model name/serial/edid
                of the display you wish to control. Is passed to `filter_monitors`
                to decide which display to use.

        Raises:
            LookupError: if a matching display could not be found
            TypeError: if the given display type is not int or str

        Example:
            ```python
            import screen_brightness_control as sbc

            # create a class for the primary monitor and then a specifically named monitor
            primary = sbc.Monitor(0)
            benq_monitor = sbc.Monitor('BenQ GL2450H')

            # check if the benq monitor is the primary one
            if primary.serial == benq_monitor.serial:
                print('BenQ GL2450H is the primary display')
            else:
                print('The primary display is', primary.name)

            # this class can also be accessed like a dictionary
            print(primary['name'])
            print(benq_monitor['name'])
            ```
        '''
        monitors_info = list_monitors_info(allow_duplicates=True)
        if isinstance(display, dict):
            if display in monitors_info:
                info = display
            else:
                info = filter_monitors(
                    display=self.get_identifier(display),
                    haystack=monitors_info
                )[0]
        else:
            info = filter_monitors(display=display, haystack=monitors_info)[0]

        # make a copy so that we don't alter the dict in-place
        info = info.copy()

        self.serial: str = info.pop('serial')
        '''the serial number of the display or (if serial is not available) an ID assigned by the OS'''
        self.name: str = info.pop('name')
        '''the monitors manufacturer name plus its model'''
        self.method = info.pop('method')
        '''the method by which this monitor can be addressed.
        This will be a class from either the windows or linux sub-module'''
        self.manufacturer: str = info.pop('manufacturer')
        '''the name of the brand of the monitor'''
        self.manufacturer_id: str = info.pop('manufacturer_id')
        '''the 3 letter manufacturing code corresponding to the manufacturer name'''
        self.model: str = info.pop('model')
        '''the general model of the display'''
        self.index: int = info.pop('index')
        '''the index of the monitor FOR THE SPECIFIC METHOD THIS MONITOR USES.'''
        self.edid: str = info.pop('edid')
        '''a unique string returned by the monitor that contains its DDC capabilities, serial and name'''

        # this assigns any extra info that is returned to this class
        # eg: the 'interface' key in XRandr monitors on Linux
        for key, value in info.items():
            if value is not None:
                setattr(self, key, value)
Args
  • display (int or str or dict): the index/name/model name/serial/edid of the display you wish to control. Is passed to filter_monitors to decide which display to use.
Raises
  • LookupError: if a matching display could not be found
  • TypeError: if the given display type is not int or str
Example
import screen_brightness_control as sbc

# create a class for the primary monitor and then a specifically named monitor
primary = sbc.Monitor(0)
benq_monitor = sbc.Monitor('BenQ GL2450H')

# check if the benq monitor is the primary one
if primary.serial == benq_monitor.serial:
    print('BenQ GL2450H is the primary display')
else:
    print('The primary display is', primary.name)

# this class can also be accessed like a dictionary
print(primary['name'])
print(benq_monitor['name'])
#   serial: str

the serial number of the display or (if serial is not available) an ID assigned by the OS

#   name: str

the monitors manufacturer name plus its model

#   method

the method by which this monitor can be addressed. This will be a class from either the windows or linux sub-module

#   manufacturer: str

the name of the brand of the monitor

#   manufacturer_id: str

the 3 letter manufacturing code corresponding to the manufacturer name

#   model: str

the general model of the display

#   index: int

the index of the monitor FOR THE SPECIFIC METHOD THIS MONITOR USES.

#   edid: str

a unique string returned by the monitor that contains its DDC capabilities, serial and name

#   def get_identifier(self, monitor: dict = None) -> Tuple[str, Union[int, str]]:
View Source
    def get_identifier(self, monitor: dict = None) -> Tuple[str, Union[int, str]]:
        '''
        Returns the piece of information used to identify this monitor.
        Will iterate through the EDID, serial, name and index and return the first
        value that is not equal to None

        Args:
            monitor (dict): extract an identifier from this dict instead of the monitor class

        Returns:
            tuple: the name of the property returned and the value of said property.
                EG: `('serial', '123abc...')` or `('name', 'BenQ GL2450H')`

        Example:
            ```python
            import screen_brightness_control as sbc
            primary = sbc.Monitor(0)
            print(primary.get_identifier())  # eg: ('serial', '123abc...')

            secondary = sbc.list_monitors_info()[1]
            print(primary.get_identifier(monitor=secondary))  # eg: ('serial', '456def...')

            # you can also use the class uninitialized
            print(sbc.Monitor.get_identifier(secondary))  # eg: ('serial', '456def...')
            ```
        '''
        if monitor is None:
            monitor = self

        for key in ('edid', 'serial', 'name', 'index'):
            value = monitor[key]
            if value is not None:
                return key, value

Returns the piece of information used to identify this monitor. Will iterate through the EDID, serial, name and index and return the first value that is not equal to None

Args
  • monitor (dict): extract an identifier from this dict instead of the monitor class
Returns
  • tuple: the name of the property returned and the value of said property. EG: ('serial', '123abc...') or ('name', 'BenQ GL2450H')
Example
import screen_brightness_control as sbc
primary = sbc.Monitor(0)
print(primary.get_identifier())  # eg: ('serial', '123abc...')

secondary = sbc.list_monitors_info()[1]
print(primary.get_identifier(monitor=secondary))  # eg: ('serial', '456def...')

# you can also use the class uninitialized
print(sbc.Monitor.get_identifier(secondary))  # eg: ('serial', '456def...')
#   def set_brightness(self, value: int, no_return: bool = True) -> Optional[int]:
View Source
    def set_brightness(self, value: int, no_return: bool = True) -> Union[None, int]:
        '''
        Sets the brightness for this display. See `set_brightness` for the full docs

        Args:
            value (int): the brightness value to set the display to (from 0 to 100)
            no_return (bool): if true, this function returns `None`
                Otherwise it returns the result of `Monitor.get_brightness`

        Returns:
            None: if `no_return==True`
            int: from 0 to 100

        Example:
            ```python
            import screen_brightness_control as sbc

            # set the brightness of the primary monitor to 50%
            primary = sbc.Monitor(0)
            primary.set_brightness(50)
            ```
        '''
        # refresh display info, in case another display has been unplugged or something
        # which would change the index of this display
        self.get_info()
        value = max(0, min(value, 100))
        self.method.set_brightness(value, display=self.index)
        if no_return:
            return None
        return self.get_brightness()

Sets the brightness for this display. See set_brightness for the full docs

Args
  • value (int): the brightness value to set the display to (from 0 to 100)
  • no_return (bool): if true, this function returns None Otherwise it returns the result of Monitor.get_brightness
Returns
  • None: if no_return==True
  • int: from 0 to 100
Example
import screen_brightness_control as sbc

# set the brightness of the primary monitor to 50%
primary = sbc.Monitor(0)
primary.set_brightness(50)
#   def get_brightness(self) -> int:
View Source
    def get_brightness(self) -> int:
        '''
        Returns the brightness of this display.

        Returns:
            int: from 0 to 100

        Example:
            ```python
            import screen_brightness_control as sbc

            # get the brightness of the primary monitor
            primary = sbc.Monitor(0)
            primary_brightness = primary.get_brightness()
            ```
        '''
        # refresh display info, in case another display has been unplugged or something
        # which would change the index of this display
        self.get_info()
        return self.method.get_brightness(display=self.index)[0]

Returns the brightness of this display.

Returns
  • int: from 0 to 100
Example
import screen_brightness_control as sbc

# get the brightness of the primary monitor
primary = sbc.Monitor(0)
primary_brightness = primary.get_brightness()
#   def fade_brightness(self, *args, **kwargs) -> Union[threading.Thread, int]:
View Source
    def fade_brightness(self, *args, **kwargs) -> Union[threading.Thread, int]:
        '''
        Fades the brightness for this display. See `fade_brightness` for the full docs

        Args:
            args (tuple): passed directly to `fade_brightness`
            kwargs (dict): passed directly to `fade_brightness`.
                The `display` and `method` kwargs are always
                overwritten.

        Returns:
            threading.Thread: if the the blocking kwarg is False
            int: if the blocking kwarg is True

        Example:
            ```python
            import screen_brightness_control as sbc

            # fade the brightness of the primary monitor to 50%
            primary = sbc.Monitor(0)
            primary.fade_brightness(50)
            ```
        '''
        # refresh display info, in case another display has been unplugged or something
        # which would change the index of this display
        self.get_info(refresh=False)
        kwargs['display'] = self.index
        # the reason we override the method kwarg here is that
        # the 'index' is method specific and `fade_brightness`
        # is a top-level function. `self.set_brightness` and `self.get_brightness`
        # call directly to the method so they don't need this step
        kwargs['method'] = self.method.__name__.lower()

        brightness = fade_brightness(*args, **kwargs)
        # fade_brightness will call the top-level get_brightness
        # function, which will return list OR int
        if isinstance(brightness, list):
            return brightness[0]
        return brightness

Fades the brightness for this display. See fade_brightness for the full docs

Args
Returns
  • threading.Thread: if the the blocking kwarg is False
  • int: if the blocking kwarg is True
Example
import screen_brightness_control as sbc

# fade the brightness of the primary monitor to 50%
primary = sbc.Monitor(0)
primary.fade_brightness(50)
#   def get_info(self, refresh: bool = True) -> dict:
View Source
    def get_info(self, refresh: bool = True) -> dict:
        '''
        Returns all known information about this monitor instance

        Args:
            refresh (bool): whether to refresh the information
                or to return the cached version

        Returns:
            dict

        Example:
            ```python
            import screen_brightness_control as sbc

            # initialize class for primary monitor
            primary = sbc.Monitor(0)
            # get the info
            info = primary.get_info()
            ```
        '''
        if not refresh:
            return vars(self)

        identifier = self.get_identifier()

        if identifier is not None:
            # refresh the info we have on this monitor
            info = filter_monitors(display=identifier[1], method=self.method.__name__)[0]
            for key, value in info.items():
                if value is not None:
                    setattr(self, key, value)

        return vars(self)

Returns all known information about this monitor instance

Args
  • refresh (bool): whether to refresh the information or to return the cached version
Returns
  • dict
Example
import screen_brightness_control as sbc

# initialize class for primary monitor
primary = sbc.Monitor(0)
# get the info
info = primary.get_info()
#   def is_active(self) -> bool:
View Source
    def is_active(self) -> bool:
        '''
        Attempts to retrieve the brightness for this display. If it works the display is deemed active

        Returns:
            bool: True means active, False means inactive

        Example:
            ```python
            import screen_brightness_control as sbc

            primary = sbc.Monitor(0)
            if primary.is_active():
                primary.set_brightness(50)
            ```
        '''
        try:
            self.get_brightness()
            return True
        except Exception:
            return False

Attempts to retrieve the brightness for this display. If it works the display is deemed active

Returns
  • bool: True means active, False means inactive
Example
import screen_brightness_control as sbc

primary = sbc.Monitor(0)
if primary.is_active():
    primary.set_brightness(50)
#   def filter_monitors( display: Union[str, int, NoneType] = None, haystack: Optional[List[dict]] = None, method: Optional[str] = None, include: List[str] = [] ) -> List[dict]:
View Source
def filter_monitors(
    display: Optional[Union[int, str]] = None,
    haystack: Optional[List[dict]] = None,
    method: Optional[str] = None,
    include: List[str] = []
) -> List[dict]:
    '''
    Searches through the information for all detected displays
    and attempts to return the info matching the value given.
    Will attempt to match against index, name, model, edid, method and serial

    Args:
        display (str or int): the display you are searching for.
            Can be serial, name, model number, edid string or index of the display
        haystack (list): the information to filter from.
            If this isn't set it defaults to the return of `list_monitors_info`
        method (str): the method the monitors use
        include (list): extra fields of information to sort by

    Raises:
        TypeError: if the display kwarg is not an int, str or None
        LookupError: if the display, does not have a match

    Returns:
        list: list of dicts

    Example:
        ```python
        import screen_brightness_control as sbc

        search = 'GL2450H'
        match = sbc.filter_displays(search)
        print(match)
        # EG output: [{'name': 'BenQ GL2450H', 'model': 'GL2450H', ... }]
        ```
    '''
    # if we have been provided with a list of monitors to sift through then use that
    # otherwise, get the info ourselves
    if haystack:
        monitors_with_duplicates = haystack
        if method is not None:
            monitors_with_duplicates = [i for i in haystack if method.lower() == i['method'].__name__.lower()]
    else:
        monitors_with_duplicates = list_monitors_info(method=method, allow_duplicates=True)

    if display is not None and type(display) not in (str, int):
        raise TypeError(f'display kwarg must be int or str, not "{type(display).__name__}"')

    # This loop does two things: 1. Filters out duplicate monitors and 2. Matches the display kwarg (if applicable)
    unique_identifiers = []
    monitors = []
    for monitor in monitors_with_duplicates:
        # find a valid identifier for a monitor, excluding any which are equal to None
        added = False
        for identifier in ['edid', 'serial', 'name', 'model'] + include:
            if monitor.get(identifier, None) is not None:
                # check we haven't already added the monitor
                if monitor[identifier] not in unique_identifiers:
                    # check if the display kwarg (if str) matches this monitor
                    if monitor[identifier] == display or not isinstance(display, str):
                        # if valid and monitor[identifier] not in unique_identifiers:
                        if not added:
                            monitors.append(monitor)
                            unique_identifiers.append(monitor[identifier])
                            added = True

                        # if the display kwarg is an integer and we are currently at that index
                        if isinstance(display, int) and len(monitors) - 1 == display:
                            return [monitor]
                        if added:
                            break
                else:
                    # if we have already added a monitor with the same identifier
                    # then any info matching this monitor will match the other one
                    # so exit the checking now
                    break

    # if no monitors matched the query OR if display kwarg was an int
    # if the latter and we made it this far then the int was out of range
    if monitors == [] or isinstance(display, int):
        msg = 'no monitors found'
        if display is not None:
            msg += f' with name/serial/model/edid/index of {repr(display)}'
        if method is not None:
            msg += f' with method of "{method}"'
        raise LookupError(msg)

    return monitors

Searches through the information for all detected displays and attempts to return the info matching the value given. Will attempt to match against index, name, model, edid, method and serial

Args
  • display (str or int): the display you are searching for. Can be serial, name, model number, edid string or index of the display
  • haystack (list): the information to filter from. If this isn't set it defaults to the return of list_monitors_info
  • method (str): the method the monitors use
  • include (list): extra fields of information to sort by
Raises
  • TypeError: if the display kwarg is not an int, str or None
  • LookupError: if the display, does not have a match
Returns
  • list: list of dicts
Example
import screen_brightness_control as sbc

search = 'GL2450H'
match = sbc.filter_displays(search)
print(match)
# EG output: [{'name': 'BenQ GL2450H', 'model': 'GL2450H', ... }]
#   def flatten_list(thick_list: List[Any]) -> List[Any]:
View Source
def flatten_list(thick_list: List[Any]) -> List[Any]:
    '''
    Internal function I use to flatten lists, because I do that often

    Args:
        thick_list (list): The list to be flattened. Can be as deep as you wish (within recursion limits)

    Returns:
        list: one dimensional

    Example:
        ```python
        import screen_brightness_control as sbc
        thick_list = [1, [2, [3, 4, 5], 6, 7], 8, [9, 10]]
        flat_list = sbc.flatten_list(thick_list)
        # Output: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
        ```
    '''
    flat_list = []
    for item in thick_list:
        if isinstance(item, list):
            flat_list += flatten_list(item)
        else:
            flat_list.append(item)
    return flat_list

Internal function I use to flatten lists, because I do that often

Args
  • thick_list (list): The list to be flattened. Can be as deep as you wish (within recursion limits)
Returns
  • list: one dimensional
Example
import screen_brightness_control as sbc
thick_list = [1, [2, [3, 4, 5], 6, 7], 8, [9, 10]]
flat_list = sbc.flatten_list(thick_list)
# Output: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]