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authorHans Verkuil <hans.verkuil@cisco.com>2012-08-14 06:10:01 -0300
committerMauro Carvalho Chehab <mchehab@redhat.com>2012-08-15 18:58:04 -0300
commit071408b6dcc1cb29150699621e13b0ddb81e3cf1 (patch)
treef48a6e8e3caf14539c1e33fe3a72d13b949d2639 /Documentation/DocBook/media/v4l/selection-api.xml
parent34affc6a5c75ce6523d7282d56c51bb36c183da7 (diff)
downloadblackbird-op-linux-071408b6dcc1cb29150699621e13b0ddb81e3cf1.tar.gz
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[media] DocBook validation fixes
More validation fixes as reported by xmllint. There are still three xmllint errors after this remaining regarding SVG file support. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'Documentation/DocBook/media/v4l/selection-api.xml')
-rw-r--r--Documentation/DocBook/media/v4l/selection-api.xml22
1 files changed, 11 insertions, 11 deletions
diff --git a/Documentation/DocBook/media/v4l/selection-api.xml b/Documentation/DocBook/media/v4l/selection-api.xml
index e7ed5077834d..4c238ce068b0 100644
--- a/Documentation/DocBook/media/v4l/selection-api.xml
+++ b/Documentation/DocBook/media/v4l/selection-api.xml
@@ -40,6 +40,7 @@ cropping and composing rectangles have the same size.</para>
<section>
<title>Selection targets</title>
+ <para>
<figure id="sel-targets-capture">
<title>Cropping and composing targets</title>
<mediaobject>
@@ -52,12 +53,12 @@ cropping and composing rectangles have the same size.</para>
</textobject>
</mediaobject>
</figure>
+ </para>
+ <para>See <xref linkend="v4l2-selection-targets" /> for more
+ information.</para>
</section>
- See <xref linkend="v4l2-selection-targets" /> for more
- information.
-
<section>
<title>Configuration</title>
@@ -216,18 +217,17 @@ composing and cropping operations by setting the appropriate targets. The V4L2
API lacks any support for composing to and cropping from an image inside a
memory buffer. The application could configure a capture device to fill only a
part of an image by abusing V4L2 API. Cropping a smaller image from a larger
-one is achieved by setting the field <structfield>
-&v4l2-pix-format;::bytesperline </structfield>. Introducing an image offsets
-could be done by modifying field <structfield> &v4l2-buffer;::m:userptr
-</structfield> before calling <constant> VIDIOC_QBUF </constant>. Those
+one is achieved by setting the field
+&v4l2-pix-format;<structfield>::bytesperline</structfield>. Introducing an image offsets
+could be done by modifying field &v4l2-buffer;<structfield>::m_userptr</structfield>
+before calling <constant> VIDIOC_QBUF </constant>. Those
operations should be avoided because they are not portable (endianness), and do
not work for macroblock and Bayer formats and mmap buffers. The selection API
deals with configuration of buffer cropping/composing in a clear, intuitive and
portable way. Next, with the selection API the concepts of the padded target
-and constraints flags are introduced. Finally, <structname> &v4l2-crop;
-</structname> and <structname> &v4l2-cropcap; </structname> have no reserved
-fields. Therefore there is no way to extend their functionality. The new
-<structname> &v4l2-selection; </structname> provides a lot of place for future
+and constraints flags are introduced. Finally, &v4l2-crop; and &v4l2-cropcap;
+have no reserved fields. Therefore there is no way to extend their functionality.
+The new &v4l2-selection; provides a lot of place for future
extensions. Driver developers are encouraged to implement only selection API.
The former cropping API would be simulated using the new one. </para>
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