About asf format [Archive]

snow_xmas

3rd May 2009, 12:42

I have a mobile mini player. It can play avi file which is encoded by MPEG-4(DivX,XviD). And I've got some asf files that the video stream's codec is Microsoft MPEG-4. Re-encoding will be so slow and unnecessary. How to re-mux them directly to avi?

setarip_old

3rd May 2009, 20:40

Hi!

Try the following:

http://www.doom9.org/index.html?/asf2avi.htm

LoRd_MuldeR

3rd May 2009, 21:11

Avidemux should be able to open ASF files and save the content to an AVI file (use "Copy" mode to avoid re-encoding).

In case Avidemux fails, MEncoder should work too...

Inspector.Gadget

3rd May 2009, 23:36

Be aware that some (maybe all) versions of Microsoft's MPEG-4 encoder are not standard compliant and your mobile player may not actually handle them.

Dark Shikari

4th May 2009, 01:19

Be aware that some (maybe all) versions of Microsoft's MPEG-4 encoder are not standard compliant and your mobile player may not actually handle them.I'm pretty sure the "all" here is correct. MSMPEG4 is not MPEG-4.

nixo

4th May 2009, 07:26

You can convert MSMPEG4 to MPEG-4 losslessly with this version of ffmpeg:
http://forum.doom9.org/showthread.php?p=701578#post701578

--
Nikolaj

Dark Shikari

4th May 2009, 07:30

You can convert MSMPEG4 to MPEG-4 losslessly with this version of ffmpeg:
http://forum.doom9.org/showthread.php?p=701578#post701578

--
NikolajLosslessly? The post doesn't seem to claim that, and I'm pretty sure ffmpeg has never had such functionality.

nixo

4th May 2009, 08:19

AFAIK the patch never made it into ffmpeg - hence the special build. As far as the process being lossless, I don't know for sure. I'm going by the "attempting lossless msmpeg4->mpeg4 conversion" that the build outputs when running a conversion.
The converted file will be slightly bigger than the original.

--
Nikolaj

EDIT: Bond mentions on page1 of the thread I linked that the conversion is supposed to be lossless:
http://forum.doom9.org/showthread.php?p=570767#post570767

benwaggoner

20th May 2009, 04:14

I'm pretty sure the "all" here is correct. MSMPEG4 is not MPEG-4.
MS MPEG-4v3 was pretty close to the ISO spec; I've heard that lossless conversion has been possible, although I've never tried it myself.

There was also the ISO MPEG-4 codec introduced along with WMV 7 which was a fully ISO compatible MPEG-4 Simple Profile bitstream.