[FFmpeg-user] Specifying Video Stream with V instead of v

[Moritz Barsnick]

Hi Josh,

On Wed, Nov 11, 2015 at 13:15:37 -0700, Josh Marell wrote:
> the shortened video file which still displays the behavior (I dropped it
> all the down to 0.5s to make it super small but still display the error)

Perfect. I had to dig through the code with a lot of av_log()s added,
and figured out that these four streams (0:3 to 0:6) do match "-c:V"
although they shouldn't, because their "stream disposition" doesn't
have the property "attached_pic". (If they did, "-c:V" wouldn't match
them.)

To check for yourself, run "ffprobe -show_streams" and check for this
from each stream:

DISPOSITION:attached_pic=0
TAG:FILENAME=small_cover_land.jpg

Apparently, the Matroska demuxer doesn't set this disposition. With
your source file, it doesn't handle the four picture streams as
"attachments", and therefore never gets to the code which sets this
disposition.

I haven't gotten further than that. I don't know enough about Matroska
to say what the demuxer thinks is "attachments", and whether the
demuxer is doing something incorrectly, or whether the streams in your
file are marked incorrectly.

> I read on the mailing list page that uncompressed files are preferred, I
> wasn't sure about the shorter video file though, so I do hope it's ok I've
> included that too.

As small as all your files were: fine by me.

Moritz