This control is intended for video capture or memory-to-memory devices that are capable of setting up the alpha conponent to some arbitrary value. The V4L2_CID_COLOR_ALPHA control allows to set the alpha channel globally to a value in range from 0 to 255.
Signed-off-by: Sylwester Nawrocki <s.nawro...@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.p...@samsung.com> --- Documentation/DocBook/media/v4l/controls.xml | 20 ++++++++++++++------ .../DocBook/media/v4l/pixfmt-packed-rgb.xml | 7 +++++-- drivers/media/video/v4l2-ctrls.c | 7 +++++++ include/linux/videodev2.h | 6 +++--- 4 files changed, 29 insertions(+), 11 deletions(-) diff --git a/Documentation/DocBook/media/v4l/controls.xml b/Documentation/DocBook/media/v4l/controls.xml index 3bc5ee8..7f99222 100644 --- a/Documentation/DocBook/media/v4l/controls.xml +++ b/Documentation/DocBook/media/v4l/controls.xml @@ -324,12 +324,6 @@ minimum value disables backlight compensation.</entry> (usually a microscope).</entry> </row> <row> - <entry><constant>V4L2_CID_LASTP1</constant></entry> - <entry></entry> - <entry>End of the predefined control IDs (currently -<constant>V4L2_CID_ILLUMINATORS_2</constant> + 1).</entry> - </row> - <row> <entry><constant>V4L2_CID_MIN_BUFFERS_FOR_CAPTURE</constant></entry> <entry>integer</entry> <entry>This is a read-only control that can be read by the application @@ -345,6 +339,20 @@ 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.</entry> </row> + <row id="v4l2-color-alpha"> + <entry><constant>V4L2_CID_COLOR_ALPHA</constant></entry> + <entry>integer</entry> + <entry> Sets the color alpha component on the capture device. It is + applicable to any pixel formats that contain the alpha component, + e.g. <link linkend="rgb-formats">packed RGB image formats</link>. + </entry> + </row> + <row> + <entry><constant>V4L2_CID_LASTP1</constant></entry> + <entry></entry> + <entry>End of the predefined control IDs (currently + <constant>V4L2_CID_COLOR_ALPHA</constant> + 1).</entry> + </row> <row> <entry><constant>V4L2_CID_PRIVATE_BASE</constant></entry> <entry></entry> diff --git a/Documentation/DocBook/media/v4l/pixfmt-packed-rgb.xml b/Documentation/DocBook/media/v4l/pixfmt-packed-rgb.xml index 4db272b..da4c360 100644 --- a/Documentation/DocBook/media/v4l/pixfmt-packed-rgb.xml +++ b/Documentation/DocBook/media/v4l/pixfmt-packed-rgb.xml @@ -428,8 +428,11 @@ colorspace <constant>V4L2_COLORSPACE_SRGB</constant>.</para> <para>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 -<link linkend="overlay">Video Overlay</link> or <link -linkend="osd">Video Output Overlay</link>.</para> +<link linkend="overlay">Video Overlay</link> or <link linkend="osd"> +Video Output Overlay</link> or when global alpha has been configured +for a <link linkend="capture">Video Capture</link> by means of +<link linkend="v4l2-color-alpha"> <constant>V4L2_CID_COLOR_ALPHA +</constant> </link> control.</para> <example> <title><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 5552f81..bd90955 100644 --- a/drivers/media/video/v4l2-ctrls.c +++ b/drivers/media/video/v4l2-ctrls.c @@ -466,6 +466,7 @@ 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_COLOR_ALPHA: return "Color Alpha"; /* MPEG controls */ /* Keep the order of the 'case's the same as in videodev2.h! */ @@ -714,6 +715,12 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type, /* Max is calculated as RGB888 that is 2^24 */ *max = 0xFFFFFF; break; + case V4L2_CID_COLOR_ALPHA: + *type = V4L2_CTRL_TYPE_INTEGER; + *step = 1; + *min = 0; + *max = 0xff; + break; case V4L2_CID_FLASH_FAULT: *type = V4L2_CTRL_TYPE_BITMASK; break; diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h index 4b752d5..42192c1 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_COLOR_ALPHA (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) -- 1.7.7.2 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html