diff options
| -rw-r--r-- | info/blueshift.texinfo | 62 | ||||
| -rw-r--r-- | src/monitor.py | 29 |
2 files changed, 84 insertions, 7 deletions
diff --git a/info/blueshift.texinfo b/info/blueshift.texinfo index dc6fd16..68707ef 100644 --- a/info/blueshift.texinfo +++ b/info/blueshift.texinfo @@ -953,13 +953,13 @@ to a monitor. @item widthmm The physical width of the monitor, measured -in millimetres. @code{None} if unknown or if -not connected. +in millimetres. @code{None} if unknown, not +defined or if not connected. @item heightmm The physical height of the monitor, measured -in millimetres. @code{None} if unknown or if -not connected. +in millimetres. @code{None} if unknown, not +defined or if not connected. @item crtc The CRT controller index. @code{None} if not @@ -976,6 +976,14 @@ is used it is probably found because it is needed for plug and play support of the monitor. @end table +The width and height are unknown if the monitor +does not specify them in the EDID if using DRM. +They are not defined the output is a projector. +If using RandR this values are probably not +correct, but the EDID can be parsed, which is +want is done by DRM. The EDID can only specify +whole centrimeters up to 255 cm. + @code{Screens} and @code{Screen} provide a set of functions for finding the output, and traversal the CRTC and screen, a monitor is connected to: @@ -1013,6 +1021,52 @@ These functions returns a list of matching @code{Output}:s. The list is empty if non are found. +Using the class @code{EDID} it is possible to +parse the extended display identification data +of an output. @code{EDID} as a constructor that +takes one argument: the EDID as stored by +@code{Output} in its variable @code{edid}. +This class can only parse EDID structure revision +1.3, which is way all monitors produced 2000 or +later should use. If the supplied EDID does +not meet this requirement an exception will be +raised by the constructor. + +An instance of @code{EDID} currently have +the following variables: + +@table @code +@item widthmm +The physical width of the monitor, measured +in millimetres. @code{None} if not, e.g. a +projector. This value is between 10 mm and 2550 +mm inclusively and is always zero modulo 10 mm. + +@item heightmm +The physical height of the monitor, measured +in millimetres. @code{None} if not, e.g. a +projector. This value is @code{None} exactly +when the value of @code{widthmm} is @code{None}. +This value is between 10 mm and 2550 mm +inclusively and is always zero modulo 10 mm. + +@item gamma +The monitor's estimated gamma characteristics, +@code{None} if not specified. The range of this +value is 1,00 to 3,55 inclusively, with a +precision of 0,01. + +@item gamma_correction +The value correlates exactly with @code{gamma}, +and is @code{None} if and only if @code{gamma} +is @code{None}. More precisely, it is the value +of @code{gamma} divided by gamma calibrated +monitors should have: 2,2. This value can be +used for gamma correction if you do not have +more exact values to use. +@end table + + @node Backlight @section Backlight diff --git a/src/monitor.py b/src/monitor.py index 2a9e2a8..499d7d0 100644 --- a/src/monitor.py +++ b/src/monitor.py @@ -473,8 +473,8 @@ class Output: @variable name:str The name of the output @variable connected:bool Whether the outout is known to be connected - @variable widthmm:int? The physical width of the monitor, measured in millimetres, `None` if unknown or not connected - @variable heigthmm:int? The physical height of the monitor, measured in millimetres, `None` if unknown or not connected + @variable widthmm:int? The physical width of the monitor, measured in millimetres, `None` if unknown, not defined or not connected + @variable heigthmm:int? The physical height of the monitor, measured in millimetres, `None` if unknown, not defined or not connected @variable crtc:int? The CRTC index, `None` if not connected @variable screen:int? The screen index, `None` if none @variable edid:str? Extended display identification data, `None` if none @@ -498,28 +498,51 @@ class Output: return '[Name: %s, Connected: %s, Width: %s, Height: %s, CRTC: %s, Screen: %s, EDID: %s]' % rc -class EDID: # TODO demo and document this +class EDID: # TODO demo this + ''' + Data structure for parsed EDID:s + + @var widthmm:int? The physical width of the monitor, measured in millimetres, `None` if not defined + @var heightmm:int? The physical height of the monitor, measured in millimetres, `None` if not defined or not connected + @var gamma:float? The monitor's estimated gamma characteristics, `None` if not specified + @var gamma_correction:float? Gamma correction to use unless you know more exact values, calculated from `gamma` + ''' def __init__(self, edid): + ''' + Constructor, parses an EDID + + @param edid:str The edid to parse, in hexadecimal representation + @exception :Exception Raised when the EDID is not of a support format + ''' + # Check the length of the EDID if not len(edid) == 256: raise Exception('EDID version not support, length mismatch') + # Check the EDID:s magic number if not edid[:16].upper() == '00FFFFFFFFFFFF00': raise Exception('EDID version not support, magic number mismatch') + # Convert to raw byte representation edid = [int(edid[i * 2 : i * 2 + 2], 16) for i in range(128)] + # Check EDID structure version and revision if not edid[18] == 1: raise Exception('EDID version not support, version mismatch, only 1.3 supported') if not edid[19] == 3: raise Exception('EDID version not support, revision mismatch, only 1.3 supported') + # Get the maximum displayable image dimension self.widthmm = edid[21] * 10 self.heightmm = edid[22] * 10 if (self.widthmm == 0) or (self.heightmm == 0): + # If either is zero, it is undefined, e.g. a projector self.widthmm = None self.heightmm = None + # Get the gamma characteristics if (edid[23] == 255): + # Not specified if FFh self.gamma = None self.gamma_correction = None else: self.gamma = (edid[23] + 100) / 100 self.gamma_correction = self.gamma / 2.2 + # Check the EDID checksum if not sum(edid) % 256 == 0: raise Exception('Incorrect EDID checksum') |