[media] DocBook media: clarify v4l2_pix_format and v4l2_pix_format_mplane fields
Be more specific with regards to how some of these fields are interpreted. In particular the height value and which fields can be set by the application. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
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@ -25,7 +25,12 @@ capturing and output, for overlay frame buffer formats see also
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<row>
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<row>
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<entry>__u32</entry>
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<entry>__u32</entry>
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<entry><structfield>height</structfield></entry>
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<entry><structfield>height</structfield></entry>
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<entry>Image height in pixels.</entry>
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<entry>Image height in pixels. If <structfield>field</structfield> is
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one of <constant>V4L2_FIELD_TOP</constant>, <constant>V4L2_FIELD_BOTTOM</constant>
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or <constant>V4L2_FIELD_ALTERNATE</constant> then height refers to the
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number of lines in the field, otherwise it refers to the number of
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lines in the frame (which is twice the field height for interlaced
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formats).</entry>
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</row>
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</row>
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<row>
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<row>
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<entry spanname="hspan">Applications set these fields to
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<entry spanname="hspan">Applications set these fields to
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@ -54,7 +59,7 @@ linkend="reserved-formats" /></entry>
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can request to capture or output only the top or bottom field, or both
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can request to capture or output only the top or bottom field, or both
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fields interlaced or sequentially stored in one buffer or alternating
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fields interlaced or sequentially stored in one buffer or alternating
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in separate buffers. Drivers return the actual field order selected.
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in separate buffers. Drivers return the actual field order selected.
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For details see <xref linkend="field-order" />.</entry>
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For more details on fields see <xref linkend="field-order" />.</entry>
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</row>
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</row>
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<row>
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<row>
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<entry>__u32</entry>
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<entry>__u32</entry>
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@ -81,7 +86,10 @@ plane and is divided by the same factor as the
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example the Cb and Cr planes of a YUV 4:2:0 image have half as many
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example the Cb and Cr planes of a YUV 4:2:0 image have half as many
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padding bytes following each line as the Y plane. To avoid ambiguities
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padding bytes following each line as the Y plane. To avoid ambiguities
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drivers must return a <structfield>bytesperline</structfield> value
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drivers must return a <structfield>bytesperline</structfield> value
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rounded up to a multiple of the scale factor.</para></entry>
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rounded up to a multiple of the scale factor.</para>
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<para>For compressed formats the <structfield>bytesperline</structfield>
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value makes no sense. Applications and drivers must set this to 0 in
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that case.</para></entry>
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</row>
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</row>
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<row>
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<row>
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<entry>__u32</entry>
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<entry>__u32</entry>
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@ -97,7 +105,8 @@ hold an image.</entry>
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<entry>&v4l2-colorspace;</entry>
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<entry>&v4l2-colorspace;</entry>
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<entry><structfield>colorspace</structfield></entry>
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<entry><structfield>colorspace</structfield></entry>
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<entry>This information supplements the
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<entry>This information supplements the
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<structfield>pixelformat</structfield> and must be set by the driver,
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<structfield>pixelformat</structfield> and must be set by the driver for
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capture streams and by the application for output streams,
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see <xref linkend="colorspaces" />.</entry>
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see <xref linkend="colorspaces" />.</entry>
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</row>
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</row>
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<row>
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<row>
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@ -135,7 +144,7 @@ set this field to zero.</entry>
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<entry>__u16</entry>
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<entry>__u16</entry>
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<entry><structfield>bytesperline</structfield></entry>
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<entry><structfield>bytesperline</structfield></entry>
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<entry>Distance in bytes between the leftmost pixels in two adjacent
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<entry>Distance in bytes between the leftmost pixels in two adjacent
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lines.</entry>
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lines. See &v4l2-pix-format;.</entry>
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</row>
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</row>
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<row>
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<row>
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<entry>__u16</entry>
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<entry>__u16</entry>
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@ -154,12 +163,12 @@ set this field to zero.</entry>
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<row>
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<row>
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<entry>__u32</entry>
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<entry>__u32</entry>
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<entry><structfield>width</structfield></entry>
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<entry><structfield>width</structfield></entry>
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<entry>Image width in pixels.</entry>
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<entry>Image width in pixels. See &v4l2-pix-format;.</entry>
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</row>
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</row>
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<row>
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<row>
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<entry>__u32</entry>
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<entry>__u32</entry>
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<entry><structfield>height</structfield></entry>
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<entry><structfield>height</structfield></entry>
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<entry>Image height in pixels.</entry>
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<entry>Image height in pixels. See &v4l2-pix-format;.</entry>
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</row>
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</row>
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<row>
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<row>
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<entry>__u32</entry>
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<entry>__u32</entry>
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