[streaming] Aspect ratio change not preserved when transcoding

[Bjørn Olav Ruud]

I have a multicast stream in raw UDP MPEG TS (MPEG-2 video, layer 2
audio) as input, which is transcoded to MPEG-4 video and sent back out
as a new multicast stream. This is the sout command used with VLC
0.8.6 on Gentoo Linux:

'#transcode{vcodec=mp4v,vb=2000,deinterlace}:std{access=udp,mux=ts,url=239.192.0.63}'

The input stream has both 4:3 and 16:9 material, and on occasion sends
material in reduced resolution (544x576, both 4:3 and 16:9 DAR).
Aspect and resolution switching works fine if the original TS is
played back, both as a stream and as a file. If the stream is
transcoded, the aspect ratio information seems to be lost. The output
stream gets an initial aspect and never changes. If a resolution
change occurs the image gets corrupted.

Does anyone have a solution for this?

I have a sample that starts as 16:9, changes to 4:3, and finally to
16:9 with a reduced source resolution. The file is rather large at 72
MB, so I don't have an immediate way of hosting it. Let me know if
anyone wants it uploaded somewhere.


Regards,
Bjorn Ruud

-- 
This is the streaming mailing-list, see http://www.videolan.org/streaming/
To unsubscribe, please read http://www.videolan.org/support/lists.html