| Message ID | 20250203085853.1361401-12-sakari.ailus@linux.intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | Sub-device configuration models | expand |
Hi Sakari, On 03.02.2025 10:58, Sakari Ailus wrote: > Caution: This is an external email. Please take care when clicking links or opening attachments. When in doubt, report the message using the 'Report this email' button > > > Document the use of luma-only mbus codes for camera sensors and how the > V4L2_CID_COLOUR_PATTERN and V4L2_CID_COLOUR_PATTERN_FLIP controls are used > to convey the colour filter array pattern on UAPI. > > Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> > --- > .../userspace-api/media/drivers/camera-sensor.rst | 13 +++++++++++++ > .../media/v4l/ext-ctrls-image-source.rst | 4 ++++ > 2 files changed, 17 insertions(+) > > diff --git a/Documentation/userspace-api/media/drivers/camera-sensor.rst b/Documentation/userspace-api/media/drivers/camera-sensor.rst > index 5bc4c79d230c..91e5305458b9 100644 > --- a/Documentation/userspace-api/media/drivers/camera-sensor.rst > +++ b/Documentation/userspace-api/media/drivers/camera-sensor.rst > @@ -41,6 +41,19 @@ format set on a source pad at the end of the device's internal pipeline. > > Most sensor drivers are implemented this way. > > +V4L2_CID_COLOUR_PATTERN, luma-only mbus formats, flipping and cropping > +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > + > +For raw image data originating from camera sensors, :ref:`luma-only mbus codes > +MEDIA_BUS_FMT_Yx_1Xx (where 'x' is the bit depth) <v4l2-mbus-pixelcode-yuv8>` > +are used as Colour Filter Array (CFA) agnostic raw formats. The > +``V4L2_CID_COLOUR_PATTERN <image-source-control-colour-pattern>`` control in the > +same sub-device defines the native colour pattern of the device. Flipping may > +further affect the readout pattern as indicated by the > +``V4L2_CID_COLOUR_PATTERN_FLIP <image-source-control-colour-pattern-flip>`` > +control. Further on, cropping also has an effect on the pattern if cropped > +amount is not divisible by the size of the pattern, horizontally and vertically. > + Ok, so it is clear now, the V4L2_CID_COLOUR_PATTERN stands for the "native colour pattern", as opposed to the "readout pattern". It is good to make the distinction. Maybe the V4L2_CID_COLOUR_PATTERN control description in patch #7 could also be made more clear with regards to native vs readout pattern? "This control determines the colour components and pixel order in the sensor's CFA (Colour Filter Array)..." => "This control reports the colour components and native pixel order in the sensor's CFA (Colour Filter Array)..." ? Thanks, Mirela > Frame interval configuration > ---------------------------- > > diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-image-source.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-image-source.rst > index ecfa38c118e3..4b98a740236a 100644 > --- a/Documentation/userspace-api/media/v4l/ext-ctrls-image-source.rst > +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-image-source.rst > @@ -93,6 +93,8 @@ Image Source Control IDs > is reported as being (say) 128, then a value of 192 would represent > a gain of exactly 1.5. > > +.. _image-source-control-colour-pattern: > + > ``V4L2_CID_COLOUR_PATTERN (integer)`` > This control determines the colour components and pixel order in the > sensor's CFA (Colour Filter Array) when used in conjunction with > @@ -103,6 +105,8 @@ Image Source Control IDs > > This is a read-only control. > > +.. _image-source-control-colour-pattern-flip: > + > ``V4L2_CID_COLOUR_PATTERN_FLIP (bitmask)`` > Whether the horizontal or vertical flipping controls (V4L2_CID_HFLIP and > V4L2_CID_VFLIP) have an effect on the pixel order of the output colour > -- > 2.39.5 >
diff --git a/Documentation/userspace-api/media/drivers/camera-sensor.rst b/Documentation/userspace-api/media/drivers/camera-sensor.rst index 5bc4c79d230c..91e5305458b9 100644 --- a/Documentation/userspace-api/media/drivers/camera-sensor.rst +++ b/Documentation/userspace-api/media/drivers/camera-sensor.rst @@ -41,6 +41,19 @@ format set on a source pad at the end of the device's internal pipeline. Most sensor drivers are implemented this way. +V4L2_CID_COLOUR_PATTERN, luma-only mbus formats, flipping and cropping +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +For raw image data originating from camera sensors, :ref:`luma-only mbus codes +MEDIA_BUS_FMT_Yx_1Xx (where 'x' is the bit depth) <v4l2-mbus-pixelcode-yuv8>` +are used as Colour Filter Array (CFA) agnostic raw formats. The +``V4L2_CID_COLOUR_PATTERN <image-source-control-colour-pattern>`` control in the +same sub-device defines the native colour pattern of the device. Flipping may +further affect the readout pattern as indicated by the +``V4L2_CID_COLOUR_PATTERN_FLIP <image-source-control-colour-pattern-flip>`` +control. Further on, cropping also has an effect on the pattern if cropped +amount is not divisible by the size of the pattern, horizontally and vertically. + Frame interval configuration ---------------------------- diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-image-source.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-image-source.rst index ecfa38c118e3..4b98a740236a 100644 --- a/Documentation/userspace-api/media/v4l/ext-ctrls-image-source.rst +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-image-source.rst @@ -93,6 +93,8 @@ Image Source Control IDs is reported as being (say) 128, then a value of 192 would represent a gain of exactly 1.5. +.. _image-source-control-colour-pattern: + ``V4L2_CID_COLOUR_PATTERN (integer)`` This control determines the colour components and pixel order in the sensor's CFA (Colour Filter Array) when used in conjunction with @@ -103,6 +105,8 @@ Image Source Control IDs This is a read-only control. +.. _image-source-control-colour-pattern-flip: + ``V4L2_CID_COLOUR_PATTERN_FLIP (bitmask)`` Whether the horizontal or vertical flipping controls (V4L2_CID_HFLIP and V4L2_CID_VFLIP) have an effect on the pixel order of the output colour
Document the use of luma-only mbus codes for camera sensors and how the V4L2_CID_COLOUR_PATTERN and V4L2_CID_COLOUR_PATTERN_FLIP controls are used to convey the colour filter array pattern on UAPI. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> --- .../userspace-api/media/drivers/camera-sensor.rst | 13 +++++++++++++ .../media/v4l/ext-ctrls-image-source.rst | 4 ++++ 2 files changed, 17 insertions(+)