diff options
| author | Hans Verkuil <hverkuil@xs4all.nl> | 2010-03-27 14:10:37 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2010-05-19 12:58:09 -0300 |
| commit | 37089368c1b1bea3c71217163e6d5d3b01ef1f19 (patch) | |
| tree | 59bc5047fae96e5d55aff71848cddfcedf60f741 | |
| parent | 092501936fc128992456a086193746cf34642815 (diff) | |
V4L/DVB: v4l spec: document what odd and even fields are
Document that odd == top and even == bottom. I can never remember this,
so it is probably worth documenting.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
| -rw-r--r-- | Documentation/DocBook/v4l/io.xml | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/Documentation/DocBook/v4l/io.xml b/Documentation/DocBook/v4l/io.xml index e870330cbf7..bb685ed6fe7 100644 --- a/Documentation/DocBook/v4l/io.xml +++ b/Documentation/DocBook/v4l/io.xml @@ -918,8 +918,8 @@ order</emphasis>.</para> <para>When the driver provides or accepts images field by field rather than interleaved, it is also important applications understand -how the fields combine to frames. We distinguish between top and -bottom fields, the <emphasis>spatial order</emphasis>: The first line +how the fields combine to frames. We distinguish between top (aka odd) and +bottom (aka even) fields, the <emphasis>spatial order</emphasis>: The first line of the top field is the first line of an interlaced frame, the first line of the bottom field is the second line of that frame.</para> @@ -972,12 +972,12 @@ between <constant>V4L2_FIELD_TOP</constant> and <row> <entry><constant>V4L2_FIELD_TOP</constant></entry> <entry>2</entry> - <entry>Images consist of the top field only.</entry> + <entry>Images consist of the top (aka odd) field only.</entry> </row> <row> <entry><constant>V4L2_FIELD_BOTTOM</constant></entry> <entry>3</entry> - <entry>Images consist of the bottom field only. + <entry>Images consist of the bottom (aka even) field only. Applications may wish to prevent a device from capturing interlaced images because they will have "comb" or "feathering" artefacts around moving objects.</entry> |