From cc1d327232759647ea56725eab1c6b16c92d52fa Mon Sep 17 00:00:00 2001 From: Sylwester Nawrocki Date: Mon, 14 Nov 2011 08:48:18 -0300 Subject: [PATCH] [media] v4l: Add new alpha component control The V4L2_CID_ALPHA_COMPONENT control is intended for the video capture or memory-to-memory devices that are capable of setting up the per-pixel alpha component to some arbitrary value. It allows to set the alpha component for all pixels to an arbitrary value. Signed-off-by: Sylwester Nawrocki Signed-off-by: Kyungmin Park Acked-by: Laurent Pinchart Signed-off-by: Mauro Carvalho Chehab --- Documentation/DocBook/media/v4l/compat.xml | 11 ++++++++++ Documentation/DocBook/media/v4l/controls.xml | 25 ++++++++++++++++------ .../DocBook/media/v4l/pixfmt-packed-rgb.xml | 7 ++++-- drivers/media/video/v4l2-ctrls.c | 1 + include/linux/videodev2.h | 6 +++--- 5 files changed, 39 insertions(+), 11 deletions(-) diff --git a/Documentation/DocBook/media/v4l/compat.xml b/Documentation/DocBook/media/v4l/compat.xml index 8b44a43..12ba262 100644 --- a/Documentation/DocBook/media/v4l/compat.xml +++ b/Documentation/DocBook/media/v4l/compat.xml @@ -2379,6 +2379,17 @@ that used it. It was originally scheduled for removal in 2.6.35. +
+ V4L2 in Linux 3.3 + + + Added V4L2_CID_ALPHA_COMPONENT control + to the User controls class. + + + +
+
Relation of V4L2 to other Linux multimedia APIs diff --git a/Documentation/DocBook/media/v4l/controls.xml b/Documentation/DocBook/media/v4l/controls.xml index c0422c6..a1be378 100644 --- a/Documentation/DocBook/media/v4l/controls.xml +++ b/Documentation/DocBook/media/v4l/controls.xml @@ -324,12 +324,6 @@ minimum value disables backlight compensation. (usually a microscope). - V4L2_CID_LASTP1 - - End of the predefined control IDs (currently -V4L2_CID_ILLUMINATORS_2 + 1). - - V4L2_CID_MIN_BUFFERS_FOR_CAPTURE integer This is a read-only control that can be read by the application @@ -345,6 +339,25 @@ and used as a hint to determine the number of OUTPUT buffers to pass to REQBUFS. The value is the minimum number of OUTPUT buffers that is necessary for hardware to work. + + V4L2_CID_ALPHA_COMPONENT + integer + Sets the alpha color component on the capture device or on + the capture buffer queue of a mem-to-mem device. When a mem-to-mem + device produces frame format that includes an alpha component + (e.g. packed RGB image formats) + and the alpha value is not defined by the mem-to-mem input data + this control lets you select the alpha component value of all + pixels. It is applicable to any pixel format that contains an alpha + component. + + + + V4L2_CID_LASTP1 + + End of the predefined control IDs (currently + V4L2_CID_ALPHA_COMPONENT + 1). + V4L2_CID_PRIVATE_BASE diff --git a/Documentation/DocBook/media/v4l/pixfmt-packed-rgb.xml b/Documentation/DocBook/media/v4l/pixfmt-packed-rgb.xml index ba56536..166c8d6 100644 --- a/Documentation/DocBook/media/v4l/pixfmt-packed-rgb.xml +++ b/Documentation/DocBook/media/v4l/pixfmt-packed-rgb.xml @@ -428,8 +428,11 @@ colorspace V4L2_COLORSPACE_SRGB. Bit 7 is the most significant bit. The value of a = alpha bits is undefined when reading from the driver, ignored when writing to the driver, except when alpha blending has been negotiated for a -Video Overlay or Video Output Overlay. +Video Overlay or +Video Output Overlay or when alpha component has been configured +for a Video Capture by means of V4L2_CID_ALPHA_COMPONENT + control. <constant>V4L2_PIX_FMT_BGR24</constant> 4 × 4 pixel diff --git a/drivers/media/video/v4l2-ctrls.c b/drivers/media/video/v4l2-ctrls.c index 0f415da..3926615 100644 --- a/drivers/media/video/v4l2-ctrls.c +++ b/drivers/media/video/v4l2-ctrls.c @@ -467,6 +467,7 @@ const char *v4l2_ctrl_get_name(u32 id) case V4L2_CID_ILLUMINATORS_2: return "Illuminator 2"; case V4L2_CID_MIN_BUFFERS_FOR_CAPTURE: return "Minimum Number of Capture Buffers"; case V4L2_CID_MIN_BUFFERS_FOR_OUTPUT: return "Minimum Number of Output Buffers"; + case V4L2_CID_ALPHA_COMPONENT: return "Alpha Component"; /* MPEG controls */ /* Keep the order of the 'case's the same as in videodev2.h! */ diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h index 3d62631..2965906 100644 --- a/include/linux/videodev2.h +++ b/include/linux/videodev2.h @@ -1204,10 +1204,10 @@ enum v4l2_colorfx { #define V4L2_CID_MIN_BUFFERS_FOR_CAPTURE (V4L2_CID_BASE+39) #define V4L2_CID_MIN_BUFFERS_FOR_OUTPUT (V4L2_CID_BASE+40) -/* last CID + 1 */ -#define V4L2_CID_LASTP1 (V4L2_CID_BASE+41) +#define V4L2_CID_ALPHA_COMPONENT (V4L2_CID_BASE+41) -/* Minimum number of buffer neede by the device */ +/* last CID + 1 */ +#define V4L2_CID_LASTP1 (V4L2_CID_BASE+42) /* MPEG-class control IDs defined by V4L2 */ #define V4L2_CID_MPEG_BASE (V4L2_CTRL_CLASS_MPEG | 0x900) -- 2.7.4