Xvid decoder problem?

[nv40]

Well, I finally found the problem and got the transcoder to start working and converting my files to xvid!!!!!! (only took 2 weeks, and it was a simple typo in the config file). Now my problem is that I can't see the video on the files, I downloaded the xvid codec, but it won't work right. I used the "gspot" codec finder and it shows the files as "xvid" and it shows I have compatible codecs, but they still won't play. VLC media player is the only thing I have that will show audio AND video, everything else is just audio......I want these to work with windows media player though, any help????

[LilY0da]

I have the same problem. The XviD encoding in FFMpeg doesn't seen to work as it should :-(
It seems that the file doesn't have the right standard. The video stream isn't flagged correctly. If you open the file in virtualdub, copy the streams without altering them into another file, then the video works...

I added that to the config file, to make DivX files instead of XviD ones (in the <CustomFFmpegConversions> section)

Code:

<Conversion name="DivX custom" cmd="-y -i {SOURCE_FILE} -f avi -ab 128 -ac 2 -acodec mp3 -deinterlace -vcodec mpeg4 -aspect 4:3 -qscale 5 {DEST_FILE}" targetExtension=".avi" />

Produces an average quality file, that plays in GBPVR and media player classic

[sub]

LilYoda, I've not look into your earlier comment about the fourcc being set wrong on these avi files, but you could investigate the ffmpeg -vtag option.

[LilY0da]

I checked that option Sub.
The current versions of FFmpeg don't support the -vtag xvid option, according to some posts I read on other websites. I tried it, and it doesn't change the fourcc (I even tried forcing a fourcc of "bozo", didn't work)

Also, I tried changing the fourcc with a third party tool, and the avis still don't work... For some reason I can't pinpoint yet, the video stream can't be decoded, even when the fourcc is corrected. Could be my tool, could be the stream, haven't diagnosed yet.

However the options above work, and with the same version of FFmpeg, and produce medium to good quality DivX files (a bit big, but you can increase the qscale value to decrease the quality and the file size). I'll be using DivX until one of us finds out why FFmpeg borks its XviD creation.

[sub]

I'm not actually in a position to test this at the moment, but the xvid files were definitly playing on my machine without any problems.

[LilY0da]

If you kept one of those xvid files you created, PM me if you can send it to me (I'll find a way for you to upload it to a server of mine)... I'd like to see with my php libraries if there's a difference in the headers between your files and mine.

Could be a codec bug as well preventing playback on my machine. But I'd find it strange since other XviD files play without a problem. Only the FFmpeg created ones don't play

[sub]

I've actually just formatted my machine and reinstalled everything from scratch, so I dont have the files any more. I should be back in a fully running position later today, and will try then.

[LilY0da]

OK I think I have a bit more info. I took a sample file, and encoded in XviD in Virtual dub as well as with FFmpeg.
The syntaxes I tried on FFmpeg were

Code:

ffmpeg -y -i corse.avi -vcodec xvid -qscale 5 corsexvid.avi
ffmpeg -y -i corse.avi -vcodec xvid -qscale 5 -vtag XVID corsexvid.avi
ffmpeg -y -i corse.avi -vcodec xvid -qscale 5 -vtag "XVID" corsexvid.avi
ffmpeg -y -i corse.avi -vcodec xvid -qscale 5 -vtag bozo corsexvid.avi
ffmpeg -y -i corse.avi -vcodec xvid -qscale 5 -vtag "bozo" corsexvid.avi

All the above return the same resulting file

Here are the header contents
For VirtualDub:
[ATTACHMENT NOT FOUND]
For the FFmpeg one:
[ATTACHMENT NOT FOUND]

If you download the AVI FourCC Code changer from http://www.inmatrix.com/files/avic_download.shtml and manually change the "Codec used" field from "xvid" to "XVID", then the file is playable immediately in GBPVR and mediaplayer classic.
Here's the difference in both avis:
[ATTACHMENT NOT FOUND]

So I believe the FFmpeg code generates a lowercase fourcc. According to http://www.fourcc.org/codecs.php, it's wrong. Now it may work on some systems, for exemple if you have ffdshow associated with lowercase "xvid" fourcc. However, with a clean XP install with just the XviD codec installed, it doesn't play.

I don't have wmp10 installed so it could also be wmp10 doing the association of that FourCC to XviD codec. Don't have it so I can't tell.

I'm trying to find out now if there's a way to associate the "xvid" fourcc to the XviD codec. If anyone knows where this is defined in the OS, let me know.

[nv40]

Okay...i'm no expert on codecs, but something about what yoda is saying is correct. I downloaded the newest xvid codec, and with the installation was an .exe file that asked for a source video, and then allowed me to set the "fourcc" thing that yoda was talking about, I set it to xvid....and after that, that video would play correctly....but only that video, you have yo open each individual file with that software and change whatever it is that it changes, and then they work. Yoda, I was gonna try your divx switch, but I'm a little unhappy with the quality of the xvid files now, I don't mind them being a bit larger....I'm more concerned with the quality. Up until now I've been using nero recode, because I can shrink the file in half.....but it still looks almost identical to the original. With xvid, it's a LOT blurrier....and there are some artififacts. Any suggestions?

edit: actually, yoda....you just posted that converter thing while I was typing this......that's exactly what I was talking about, and exactly the same results I'm getting. I'm still curious if there is any way to improve the quality of the xvid conversion, in exchange for a little larger file? Oh, and I have windows media 10....so no, it doesn't automatically do the association.

[LilY0da]

Regarding quality, I don't know how to make the file quality as good as a Virtualdub re-encode would do... I don't know the dozens of parameters well enough to say what can be used to improve quality while maintaining a low bitrate.

You should try the DivX syntax I posted above and adv if quality looks OK for you. And if anyone knows enough about all those Q values and the all the other parameters you can adjust in FFmpeg, lemme know, cause I don't really know how to increase the quality of the files FFmpeg produces :-(