diff options
author | Pawel Osciak <pawel@osciak.com> | 2011-01-16 11:53:31 -0500 |
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committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2011-03-21 19:32:05 -0400 |
commit | d39155d91d034e2b2c9154892e29c8a8eb193b7f (patch) | |
tree | 4f61e74a30e17ef8381e6846056f3c3ce185e70e /Documentation/DocBook/v4l | |
parent | 87a0c94ce616b231f3c0bd09d7dbd39d43b0557a (diff) |
[media] Remove compatibility layer from multi-planar API documentation
This feature will probably be moved to libv4l2.
Signed-off-by: Pawel Osciak <pawel@osciak.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'Documentation/DocBook/v4l')
-rw-r--r-- | Documentation/DocBook/v4l/planar-apis.xml | 35 | ||||
-rw-r--r-- | Documentation/DocBook/v4l/vidioc-querycap.xml | 22 |
2 files changed, 18 insertions, 39 deletions
diff --git a/Documentation/DocBook/v4l/planar-apis.xml b/Documentation/DocBook/v4l/planar-apis.xml index 7f3f5527057e..878ce2040488 100644 --- a/Documentation/DocBook/v4l/planar-apis.xml +++ b/Documentation/DocBook/v4l/planar-apis.xml | |||
@@ -2,10 +2,10 @@ | |||
2 | <title>Single- and multi-planar APIs</title> | 2 | <title>Single- and multi-planar APIs</title> |
3 | 3 | ||
4 | <para>Some devices require data for each input or output video frame | 4 | <para>Some devices require data for each input or output video frame |
5 | to be placed in discontiguous memory buffers. In such cases one | 5 | to be placed in discontiguous memory buffers. In such cases, one |
6 | video frame has to be addressed using more than one memory address, i.e. one | 6 | video frame has to be addressed using more than one memory address, i.e. one |
7 | pointer per "plane". A plane is a sub-buffer of current frame. For examples | 7 | pointer per "plane". A plane is a sub-buffer of the current frame. For |
8 | of such formats see <xref linkend="pixfmt" />.</para> | 8 | examples of such formats see <xref linkend="pixfmt" />.</para> |
9 | 9 | ||
10 | <para>Initially, V4L2 API did not support multi-planar buffers and a set of | 10 | <para>Initially, V4L2 API did not support multi-planar buffers and a set of |
11 | extensions has been introduced to handle them. Those extensions constitute | 11 | extensions has been introduced to handle them. Those extensions constitute |
@@ -14,8 +14,8 @@ | |||
14 | <para>Some of the V4L2 API calls and structures are interpreted differently, | 14 | <para>Some of the V4L2 API calls and structures are interpreted differently, |
15 | depending on whether single- or multi-planar API is being used. An application | 15 | depending on whether single- or multi-planar API is being used. An application |
16 | can choose whether to use one or the other by passing a corresponding buffer | 16 | can choose whether to use one or the other by passing a corresponding buffer |
17 | type to its ioctl calls. Multi-planar versions of buffer types are suffixed with | 17 | type to its ioctl calls. Multi-planar versions of buffer types are suffixed |
18 | an `_MPLANE' string. For a list of available multi-planar buffer types | 18 | with an `_MPLANE' string. For a list of available multi-planar buffer types |
19 | see &v4l2-buf-type;. | 19 | see &v4l2-buf-type;. |
20 | </para> | 20 | </para> |
21 | 21 | ||
@@ -24,28 +24,9 @@ | |||
24 | <para>Multi-planar API introduces new multi-planar formats. Those formats | 24 | <para>Multi-planar API introduces new multi-planar formats. Those formats |
25 | use a separate set of FourCC codes. It is important to distinguish between | 25 | use a separate set of FourCC codes. It is important to distinguish between |
26 | the multi-planar API and a multi-planar format. Multi-planar API calls can | 26 | the multi-planar API and a multi-planar format. Multi-planar API calls can |
27 | handle all single-planar formats as well, while the single-planar API cannot | 27 | handle all single-planar formats as well (as long as they are passed in |
28 | handle multi-planar formats. Applications do not have to switch between APIs | 28 | multi-planar API structures), while the single-planar API cannot |
29 | when handling both single- and multi-planar devices and should use the | 29 | handle multi-planar formats.</para> |
30 | multi-planar API version for both single- and multi-planar formats. | ||
31 | Drivers that do not support multi-planar API can still be handled with it, | ||
32 | utilizing a compatibility layer built into standard V4L2 ioctl handling. | ||
33 | </para> | ||
34 | </section> | ||
35 | |||
36 | <section> | ||
37 | <title>Single and multi-planar API compatibility layer</title> | ||
38 | <para>In most cases<footnote><para>The compatibility layer does not cover | ||
39 | drivers that do not use video_ioctl2() call.</para></footnote>, applications | ||
40 | can use the multi-planar API with older drivers that support | ||
41 | only its single-planar version and vice versa. Appropriate conversion is | ||
42 | done seamlessly for both applications and drivers in the V4L2 core. The | ||
43 | general rule of thumb is: as long as an application uses formats that | ||
44 | a driver supports, it can use either API (although use of multi-planar | ||
45 | formats is only possible with the multi-planar API). The list of formats | ||
46 | supported by a driver can be obtained using the &VIDIOC-ENUM-FMT; call. | ||
47 | It is possible, but discouraged, for a driver or an application to support | ||
48 | and use both versions of the API.</para> | ||
49 | </section> | 30 | </section> |
50 | 31 | ||
51 | <section> | 32 | <section> |
diff --git a/Documentation/DocBook/v4l/vidioc-querycap.xml b/Documentation/DocBook/v4l/vidioc-querycap.xml index 93699769cd07..f29f1b86213c 100644 --- a/Documentation/DocBook/v4l/vidioc-querycap.xml +++ b/Documentation/DocBook/v4l/vidioc-querycap.xml | |||
@@ -142,30 +142,28 @@ this array to zero.</entry> | |||
142 | <row> | 142 | <row> |
143 | <entry><constant>V4L2_CAP_VIDEO_CAPTURE</constant></entry> | 143 | <entry><constant>V4L2_CAP_VIDEO_CAPTURE</constant></entry> |
144 | <entry>0x00000001</entry> | 144 | <entry>0x00000001</entry> |
145 | <entry>The device supports single-planar formats through the <link | 145 | <entry>The device supports the single-planar API through the <link |
146 | linkend="capture">Video Capture</link> interface. An application can use either | 146 | linkend="capture">Video Capture</link> interface.</entry> |
147 | <link linkend="planar-apis">the single or the multi-planar API</link>.</entry> | ||
148 | </row> | 147 | </row> |
149 | <row> | 148 | <row> |
150 | <entry><constant>V4L2_CAP_VIDEO_CAPTURE_MPLANE</constant></entry> | 149 | <entry><constant>V4L2_CAP_VIDEO_CAPTURE_MPLANE</constant></entry> |
151 | <entry>0x00001000</entry> | 150 | <entry>0x00001000</entry> |
152 | <entry>The device supports multi-planar formats through the <link | 151 | <entry>The device supports the |
153 | linkend="capture">Video Capture</link> interface. An application has to use the | 152 | <link linkend="planar-apis">multi-planar API</link> through the |
154 | <link linkend="planar-apis">multi-planar API</link>.</entry> | 153 | <link linkend="capture">Video Capture</link> interface.</entry> |
155 | </row> | 154 | </row> |
156 | <row> | 155 | <row> |
157 | <entry><constant>V4L2_CAP_VIDEO_OUTPUT</constant></entry> | 156 | <entry><constant>V4L2_CAP_VIDEO_OUTPUT</constant></entry> |
158 | <entry>0x00000002</entry> | 157 | <entry>0x00000002</entry> |
159 | <entry>The device supports single-planar formats through the <link | 158 | <entry>The device supports the single-planar API through the <link |
160 | linkend="output">Video Output</link> interface. An application can use either | 159 | linkend="output">Video Output</link> interface.</entry> |
161 | <link linkend="planar-apis">the single or the multi-planar API</link>.</entry> | ||
162 | </row> | 160 | </row> |
163 | <row> | 161 | <row> |
164 | <entry><constant>V4L2_CAP_VIDEO_OUTPUT_MPLANE</constant></entry> | 162 | <entry><constant>V4L2_CAP_VIDEO_OUTPUT_MPLANE</constant></entry> |
165 | <entry>0x00002000</entry> | 163 | <entry>0x00002000</entry> |
166 | <entry>The device supports multi-planar formats through the <link | 164 | <entry>The device supports the |
167 | linkend="output">Video Output</link> interface. An application has to use the | 165 | <link linkend="planar-apis">multi-planar API</link> through the |
168 | <link linkend="planar-apis">multi-planar API</link>.</entry> | 166 | <link linkend="output">Video Output</link> interface.</entry> |
169 | </row> | 167 | </row> |
170 | <row> | 168 | <row> |
171 | <entry><constant>V4L2_CAP_VIDEO_OVERLAY</constant></entry> | 169 | <entry><constant>V4L2_CAP_VIDEO_OVERLAY</constant></entry> |