rmvb->avi bus error

[mkobayashi]

Hoping major can shed some light on this problem...

I have been encoding many rm and rmvb files with ffmpegx 0.0.9w for some time now with no problems (thanks major!) - I usually accept the default output encoding (AVI DivX) but sometimes turn down the video bitrate (leaving the video size the same) to save on output file size and I always adjust the audio sampling and bitrate to be as close to the source as possible (which may be useless but seems not to hurt anything at least).

I ran into a problem with one file a few days ago, though:

Encoding started on Sat Sep 9 12:36:29 PDT 2006
MEncoder dev-CVS-051126-18:35-3.3 (C) 2000-2005 MPlayer Team
Mac OSX static build for ffmpegX
AltiVec found
CPU: PowerPC
success: format: 0 data: 0x0 - 0x14090291
REAL file format detected.
Stream description: Video Stream
Stream mimetype: video/x-pn-realvideo
Stream description: Audio Stream
Stream mimetype: audio/x-pn-realaudio
Stream mimetype: logical-fileinfo
sh: line 1: 11365 Bus error '/Library/Application Support/ffmpegX/mencoder' /Users/smcs/Desktop/dn\ moovs/im2.rmvb -oac lavc -lavcopts acodec=mp3:abitrate=64 -srate 44100 -aid 0 -ovc lavc -sws 0 -lavcopts threads=2:vcodec=mpeg4:vbitrate=581:keyint=240:vqm in=2:vqmax=15 -ofps 29.97 -vop scale=384:256 -noodml -ffourcc DIVX -o /Users/smcs/Desktop/dn\ moovs/im2.rmvb.ff.avi

this file was an rmvb (360x240), but when i tried to encode it the first time I received an alert about the output width not being divisible by 16. Every other rm/rmvb file I had processed had a width divisible by 16. I upped the output video size to 384x256 to address this (as you can see in the command output) and that's when the bus error emerged. I tried 336x224 with the same result. It would seem from my results that there is a problem when the input video size is not divisible by 16. Unfortunately I don't have another rm/rmvb file with a different width from a multiple of 16 to confirm this.

Just as an experiment, I was able to get ffmpegx to partially encode this file using mencoder to H.264, but the encoding stopped after producing the 264 file (after 6 hours), complaining about 'movtowav' (sorry I wasn't able to save the output that time). The 264 file was playable in VLC, though without sound. What I really want to do is produce an avi, though.

Running OS X 10.4.7 on a 1GHz G4 AlBook, 1 GB RAM, many GBs HD space.

[HM]

Hi there,

I haven't convert one iota rmvb but I 've been trying. The rmvb folder and file are in Chinese so after I changed the name into English and using AviSynth with VirtualDubMod it says it can't find the file that has \??????. Should I be using something else. Thanks

[mkobayashi]

I would hope to hear an opinion/evaluation from major on my original post - is there an ffmpeg issue with transcoding rm/rmvb files with pixel widths *not* a multiple of 16? If not, what would be a workaround?

[major]

I've not heard before about that, but it could be perfectly possible. Unfortunately to make sure about that, the only way is to actually replace your file with another being multiple of 16 and see if that does make any difference. You should be able to find many of them online.