path: root/Documentation/video4linux
diff options
authorHans Verkuil <>2015-03-09 10:06:55 -0300
committerMauro Carvalho Chehab <>2015-04-02 20:33:37 -0300
commitba24b442033b7f50e24798685f4b24b8e4c3aaa2 (patch)
tree8a2d5ef9310e2b2bf4d353cbea643127d1548fe0 /Documentation/video4linux
parent9c35bd48d54345b2c89426dd2efdb33adaa0aac3 (diff)
[media] vivid: do not allow video loopback for SEQ_TB/BT
Sequential top-bottom/bottom-top fields are not supported as video loopback. This is too much work to implement for field settings that are rarely used. Signed-off-by: Hans Verkuil <> Signed-off-by: Mauro Carvalho Chehab <>
Diffstat (limited to 'Documentation/video4linux')
1 files changed, 5 insertions, 0 deletions
diff --git a/Documentation/video4linux/vivid.txt b/Documentation/video4linux/vivid.txt
index 6cfc8541a362..cd4b5a1ac529 100644
--- a/Documentation/video4linux/vivid.txt
+++ b/Documentation/video4linux/vivid.txt
@@ -912,6 +912,11 @@ looped to the video input provided that:
sequence and field counting in struct v4l2_buffer on the capture side may not
be 100% accurate.
+- field settings V4L2_FIELD_SEQ_TB/BT are not supported. While it is possible to
+ implement this, it would mean a lot of work to get this right. Since these
+ field values are rarely used the decision was made not to implement this for
+ now.
- on the input side the "Standard Signal Mode" for the S-Video input or the
"DV Timings Signal Mode" for the HDMI input should be configured so that a
valid signal is passed to the video input.