[FFmpeg-trac] #1387(undetermined:new): v4l2 uses wrong (default) parameters
FFmpeg
trac at avcodec.org
Sat Mar 9 22:18:31 CET 2013
#1387: v4l2 uses wrong (default) parameters
-------------------------------------+-------------------------------------
Reporter: burek | Owner:
Type: defect | Status: new
Priority: normal | Component:
Version: unspecified | undetermined
Keywords: v4l2 | Resolution:
Blocking: | Blocked By:
Analyzed by developer: 0 | Reproduced by developer: 0
-------------------------------------+-------------------------------------
Comment (by dronus):
The bug is still there. -pixel_format is needed to set the pixel format
again already selected by v4l2-ctl before.
And for the worse, this will in turn reset some other settings done by
v4l2-ctl. For example, exposure mode is changed on some cameras. It seems
that the format decision is assumed to take place prior to the other
settings. The format can only be changed in close state, while the
controls can be changed while capturing. So it may be incorrect to change
the pixel format by ffmpeg without the ability to reapply the control
settings.
I suggest either add a full control interface, or remove the pixel format
setup from v4l2.c and just honor what was set by tools like v4l2-ctl
before.
Adding an control interface is the issue of
https://ffmpeg.org/trac/ffmpeg/ticket/2305 too.
--
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/1387#comment:5>
FFmpeg <http://ffmpeg.org>
FFmpeg issue tracker
More information about the FFmpeg-trac
mailing list