ffmpeg and multistream WMV files

jroyce · 01-14-2008, 09:43 PM

I have written a script which downloads the Swedish TV program "RAPPORT" each day and then converts it to TiVo format so that my wife can watch her local news. This is working well, except that the resolution of the program is only 384x288, which results in a so-so picture quality on our TV.

Based on ffmpeg's output, it appears that there is a 640x480 video stream in the same WMV file as the one I am currently converting. When I start ffmpeg, I see the following:

Code:

FFmpeg version SVN-rUNKNOWN, Copyright (c) 2000-2004 Fabrice Bellard
  configuration:  --enable-gpl --enable-pp --enable-pthreads --enable-vorbis --enable-libogg --enable-a52 --enable-dts --enable-libgsm --enable-dc1394 --disable-debug --enable-shared --prefix=/usr
  libavutil version: 0d.49.0.0
  libavcodec version: 0d.51.11.0
  libavformat version: 0d.50.5.0
  built on Jan 28 2007 22:48:38, gcc: 4.1.2 20070106 (prerelease) (Ubuntu 4.1.1-21ubuntu7)
[wmv3 @ 0xb7e28508]Header: 4C291A01

Seems that stream 3 comes from film source: 1000.00 (1000/1) -> 25.00 (25/1)
Input #0, asf, from '/mnt/SharedSpace/080114rapport1930.wmv':
  Duration: 00:29:52.5, start: 5.000000, bitrate: 655 kb/s
  Stream #0.0: Audio: wmav2, 48000 Hz, stereo, 64 kb/s
  Stream #0.1: Video: wmv3, 640x480, 1000.00 fps(r)
  Stream #0.2: Audio: wmav2, 44100 Hz, stereo, 31 kb/s
  Stream #0.3: Video: wmv3, yuv420p, 384x288, 25.00 fps(r)

Currently, I map streams 0.3 and 0.2 to the MPEG file that my TiVo uses. What I would like to do is map 0.1 as the video stream. However, ffmpeg converts no frames when I do this. I think this is due to the fact that the fps rate is being incorrectly read as 1000.00 fps.

When I stream this file on a Win PC, the video is displayed as 640x480 in Windows Media Player.

I've tried ripping the WMV file using mplayer, mmsrip and mimms, but they all result in the same type of video.

The other (perhaps unrelated) issue is that the download of the WMV file takes longer than the actual video, which seems odd since this is a streaming file which one would normally watch after only downloading a small buffer.

Thoughts?

jroyce · 01-15-2008, 10:50 AM

The Microsoft website has some information about how mms works. It says:

Quote:

Multiple-bit-rate files contain a number of video streams—each of which are encoded at a different bit rate. These files enable the server to perform intelligent streaming. When using intelligent streaming, Windows Media Player sends feedback to the Windows Media server about current network conditions. The Windows Media server then delivers the most appropriate video stream for the current bandwidth from among the streams that are contained in the file.

So I am thinking that MiMMS, MMSRIP and MPlayer are all downloading a low resolution video because the server thinks that my client side has low bandwidth. (This is not true--my Ubuntu box has a LAN connection directly to my router and other downloads occur very quickly. I've had Bittorrent files download at 2400 kbps and faster.)

I wonder if there is a way to force the rip clients to download a higher bandwidth stream?

Tonight I plan to go home and try on a Suse box which has considerably more processing power than my Ubuntu box. I will report back.

jroyce · 01-17-2008, 10:07 PM

So I discovered that (as of now) only VLC seems to be able to do this. The other programs I tried all default to the lowest bitrate file, but VLC defaults to the highest (or you can specify via command line). Now if I can just get VLC working....