Decoding WMV (MSS2 + WMAVoice) into anything ! How?

[Unclocked]

I have a few really compressed wmv files that I'd like to
a) Convert to uncompressed so as to encode later (to be playable in all players)
b) Convert to mp4 or other Android playable formats to be able to carry it in a mobile

WMV Specs:
Stream #0.0: Audio: wmavoice, 8000 Hz, 1 channels, flt, 8 kb/s
Stream #0.1: Video: MSS2 / 0x3253534D, 704x528, 200 kb/s, 1k tbr, 1k tbn, 1k tbc
Stream #0.2: Data: [0][0][0][0] / 0x0000, 4 kb/s

These files are compressed so much, and their audio so clear, that I am surprised how Microsoft could achieve such a small file size (10MB / hour). These files are a series of power point slides + screen capture + accompanying audio.

Here's what I've tried so far:
- Direct conversion from wmv to avi is not possible using ffmpeg. Please note I am not worried about this error.
(Incompatible sample format 'flt' for codec 'mp2', auto-selecting format 's16'
[buffer @ 000000000198BB80] Invalid pixel format string '-1')
- Direct conversion from wmv to AVI (or MPEG2/MP3) does happen using mencoder. But file sizes are huge (500 MB).
- Encoding the uncompressed to MP4 generally brings filesize to half (250MB), but that number is still large, and video quality is poor.
- I often see the following errors (in spite of a successful conversion)
[wmavoice @ 00000000019BFAA0] WMAPro-in-WMAVoice support not implemented. Update your FFmpeg version
to the newest one from Git. If the problem still occurs, it means that your file has a feature whic
h has not been implemented.
[wmavoice @ 00000000019BFAA0] If you want to help, upload a sample of this file to ftp://upload.ffmp
eg.org/MPlayer/incoming/ and contact the ffmpeg-devel mailing list.
Error while decoding stream #0.0
- Directly extracting only the audio using ffmpeg is not possible (because of some error)

I've tried to decode this file to uncompressed followed by encoding - with no good results. I've tried to decode audio video separately; then combine them - with good results, but resulting filesize is a concern. I've also tried to use MS Live Movie Maker to use MS tools to first decode them to WMV3 + WMAV2 (default), but the resulting filesize is still pretty large at 250 MB.


Can someone help me with,
a) all things mentioned above
b) get ffmpeg/mencoder to decode MSS2+WMAVoice correctly?
c) somehow encode those to MP4 or H.264 with filesize not greater than 25MB?


Thanks in advance for any help.

[Selur]

Direct conversion from wmv to AVI (or MPEG2/MP3) does happen using mencoder. But file sizes are huge (500 MB).

If mencoder can handle it, why not use mencoder and adjust audio&video codecs and settings to hit the size you aim for?

somehow encode those to MP4 or H.264 with filesize not greater than 25MB?

should be possible with mencoder,...

get ffmpeg/mencoder to decode MSS2+WMAVoice correctly?

confused,.. sounded like mencoder decodes the file,...

-> if you post a sample others might be able to better help

Cu Selur

[Unclocked]

Here's a part of file : https://rapidshare.com/files/838510282/01Intro.wmv

[Selur]

Audio sounds okay with aac-lc @ 16kBit:

ffmpeg -threads 8 -v -10 -y -i "01Intro.wmv" -acodec pcm_s16le -r 8000 -f wav  - | neroAacEnc -br 16000 -lc -ignorelength -if - -of "audio_16k.mp4"

but the video stream really is a problem,..

[Cornucopia]

IIRC, MSS2 is a microsoft "slide show" codec (hence the name), optimized for slideshows like PowerPoint. Note the OP's video bitrate (200kbps). No regular video at that framesize and bitrate is going to look good at all.

I suggest:
Playout & Screencap using Camstudio (etc), set fps to really LOW (like 1 FPS). Bitrate might still be higher that the original, but at least then you can use a codec for editing that is more common. However, if you DO use a low fps codec and you try to edit, you won't be able to edit any finer than your fps's resolution (in the example, it would be every 1 second).

Scott

[Selur]

yup, MSS2 is Windows Media Screen 9 Codec, strange thing is I can't get Avisynt + DirectShowSource or DirectShowSource2 to playback the file. (graph always crashes), MPlayer can handle the file through DirectShow, but mencoder can't,...
ffmpeg doesn't like it.
-> will try a bit more with mencoder tomorrow

btw. Thanks to Unlocked for the sample. (playing around with it I even found an unexpected problem in my own tool )

Cu Selur

[El Heggunte]

@ Selur: have you tried to build a graph in Graphstudio, save it, and then load it through DirectShowSource()

[Selur]

Yup. (I always build the graph manually when using DirectShowSource or DirectShowSource2, to know which decoders are used)
Atm. I suspect the problem are the DirectShowDecoders from Windows 7,.. (may be I'll try on a WinXP machine tomorrow)

[Selur]

since mplayer can playback the file through (Selected video codec: [wmsdmod] vfm: dmo (Windows Media Screen Codec 2)) from the mplayer codec pack, I just extracted all the images as uncompressed pngs:

mplayer -benchmark -nosound -mc 0 -vo png:z=0:outdir=pictures 01Intro.wmv

-> now one can encode the pngs

[poisondeathray]

directshowsource works ok if you run it through asfbin first

[Selur]

for me asfbin crashed trying to process the file,.. (tried windows command line and GUI version)
(I'm running Win7 pro 64bit)

Encoding the image sequence works fine with:

x264 --crf 18 --profile baseline --level 3.1 --partitions i4x4,p8x8,b8x8 --vbv-maxrate 14000 --vbv-bufsize 14000 --fps 4 --input-res 704x528 --output "video.mp4" "pictures\%08d.png"

-> all in all it's probably easier to really use a screen capture tool to create an intermediate file that can be reencoded,..

Cu Selur