[media] v4l: Add premultiplied alpha flag for pixel formats

When set, the new V4L2_PIX_FMT_FLAG_PREMUL_ALPHA flag indicates that the
pixel values are premultiplied by the alpha channel value.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
This commit is contained in:
Laurent Pinchart 2014-05-27 10:12:43 -03:00 committed by Mauro Carvalho Chehab
parent d52e238136
commit c96fd46afb
4 changed files with 41 additions and 5 deletions

View File

@ -135,6 +135,12 @@ extended fields were set to zero. On return drivers must set the
<constant>V4L2_PIX_FMT_PRIV_MAGIC</constant> and all the extended fields to
applicable values.</para></entry>
</row>
<row>
<entry>__u32</entry>
<entry><structfield>flags</structfield></entry>
<entry>Flags set by the application or driver, see <xref
linkend="format-flags" />.</entry>
</row>
</tbody>
</tgroup>
</table>
@ -220,9 +226,15 @@ codes can be used.</entry>
and the number of valid entries in the
<structfield>plane_fmt</structfield> array.</entry>
</row>
<row>
<entry>__u8</entry>
<entry><structfield>flags</structfield></entry>
<entry>Flags set by the application or driver, see <xref
linkend="format-flags" />.</entry>
</row>
<row>
<entry>__u8</entry>
<entry><structfield>reserved[11]</structfield></entry>
<entry><structfield>reserved[10]</structfield></entry>
<entry>Reserved for future extensions. Should be zeroed by the
application.</entry>
</row>
@ -1079,4 +1091,21 @@ concatenated to form the JPEG stream. </para>
</tbody>
</tgroup>
</table>
<table frame="none" pgwide="1" id="format-flags">
<title>Format Flags</title>
<tgroup cols="3">
&cs-def;
<tbody valign="top">
<row>
<entry><constant>V4L2_PIX_FMT_FLAG_PREMUL_ALPHA</constant></entry>
<entry>0x00000001</entry>
<entry>The color values are premultiplied by the alpha channel
value. For example, if a light blue pixel with 50% transparency was described by
RGBA values (128, 192, 255, 128), the same pixel described with premultiplied
colors would be described by RGBA values (64, 96, 128, 128) </entry>
</row>
</tbody>
</tgroup>
</table>
</section>

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@ -155,7 +155,7 @@ applications. -->
<revnumber>3.16</revnumber>
<date>2014-05-27</date>
<authorinitials>lp</authorinitials>
<revremark>Extended &v4l2-pix-format;.
<revremark>Extended &v4l2-pix-format;. Added format flags.
</revremark>
</revision>

View File

@ -256,7 +256,8 @@ static void v4l_print_format(const void *arg, bool write_only)
pix = &p->fmt.pix;
pr_cont(", width=%u, height=%u, "
"pixelformat=%c%c%c%c, field=%s, "
"bytesperline=%u, sizeimage=%u, colorspace=%d\n",
"bytesperline=%u, sizeimage=%u, colorspace=%d, "
"flags %u\n",
pix->width, pix->height,
(pix->pixelformat & 0xff),
(pix->pixelformat >> 8) & 0xff,
@ -264,7 +265,7 @@ static void v4l_print_format(const void *arg, bool write_only)
(pix->pixelformat >> 24) & 0xff,
prt_names(pix->field, v4l2_field_names),
pix->bytesperline, pix->sizeimage,
pix->colorspace);
pix->colorspace, pix->flags);
break;
case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:

View File

@ -288,6 +288,7 @@ struct v4l2_pix_format {
__u32 sizeimage;
__u32 colorspace; /* enum v4l2_colorspace */
__u32 priv; /* private data, depends on pixelformat */
__u32 flags; /* format flags (V4L2_PIX_FMT_FLAG_*) */
};
/* Pixel format FOURCC depth Description */
@ -452,6 +453,9 @@ struct v4l2_pix_format {
/* priv field value to indicates that subsequent fields are valid. */
#define V4L2_PIX_FMT_PRIV_MAGIC 0xfeedcafe
/* Flags */
#define V4L2_PIX_FMT_FLAG_PREMUL_ALPHA 0x00000001
/*
* F O R M A T E N U M E R A T I O N
*/
@ -1754,6 +1758,7 @@ struct v4l2_plane_pix_format {
* @colorspace: enum v4l2_colorspace; supplemental to pixelformat
* @plane_fmt: per-plane information
* @num_planes: number of planes for this format
* @flags: format flags (V4L2_PIX_FMT_FLAG_*)
*/
struct v4l2_pix_format_mplane {
__u32 width;
@ -1764,7 +1769,8 @@ struct v4l2_pix_format_mplane {
struct v4l2_plane_pix_format plane_fmt[VIDEO_MAX_PLANES];
__u8 num_planes;
__u8 reserved[11];
__u8 flags;
__u8 reserved[10];
} __attribute__ ((packed));
/**