This AVI file is broken (NO IT ISN'T!)

[stevefoobar]

I've seen this warning on other posts with suggested work-arounds, but I wanted to re-post this with details in the hopes this problem will get fixed because the work-arounds are not good solutions to the problem.

I get the following dialog box whenever I open A SPECIFIC type of AVI file only:

"This AVI file is broken. Seeking will not work correctly. Do you want to try to repair it? This might take a long time."

On my WinXP Pro SP3 computer, this happens ONLY with AVI video files created with my Canon PowerShot TX1 HD Videocam. The files are encoded as 1280x720, 16:9, 30 fps, MJPEG, 1411 Kbps audio at 44.1 KHz, 2 channel Microsoft PCM.

Playing them with Real Player, Windows Media Player and Quick Time is flawless without the warning and with the ability to pause and seek on the timeline at will.

Thanks!
Steve in Chicago, IL USA

[VLC_help]

Playing them with Real Player, Windows Media Player and Quick Time is flawless without the warning and with the ability to pause and seek on the timeline at will.

That doesn't mean that those files follow AVI specs. You have some short sample file you could share to us?

[tohtorrent]

Hello!
I think it is Canon's Powershot issue!
i am investigating it right know, please help me with that.

For now i know for sure that video from:
Canon A650 IS - have errors
Canon ISUX 860 IS - have errors
Canon A640 - OK (no errors)
Canon A550 – OK (no errors)
Canon SX100 – OK

Please, help me with that and test the issue on your cams.

1. shoot a video (10 sec will be enough)
2. Use DivFix++ and if you see this:


this model is affected.

3. post result in this thread

Download DivFix: http://downloads.sourceforge.net/divfix ... g_mirror=0

[stevefoobar]

I would he happy to do this...just give me a day or so unless someone beats me to it.

Steve
Chicago, IL USA

[stevefoobar]

OK, I did my testing and to be thorough, I did in on 3 different video cameras, with 3 different media players. I've got images to post but I don't know how to do it in this forum. My images are PNG files and they are on my computer, not on a web site, so I can't use a "Img" button above which expects a URL, right? How else can I do it?

Thanks

Steve
Chicago, IL USA

[VLC_help]

You can use service like imageshack to upload images and to share them.

[stevefoobar]

Here are the results of my testing 3 different cameras using the DivFix++ tool suggested:

Canon PowerShot TX1 HD Video Cam



Canon PowerShot A710-IS SD Video Cam



Flip Ultra SD Video Cam



As you can clearly see, the DivFix++ tool thinks there are 2 errors in the AVI file from the Canon PowerShot TX1 and indeed this is why the VLC Media Player also indicated an error when playing this file, however, the author has subsequently PM'd me to tell me he has discovered that Canon changed the format for their AVI files quite some time ago and both the DivFix++ tool and the author's VLC Media Player must be updated to support this change so these Canon files are not flagged with false errors and also play correctly.

[VLC_help]

Could you ask from the author what that change was?

[stevefoobar]

I have PM'd the author and requested that he follow-up and post this information in this thread.

[tohtorrent]

Hi, one person said this:

"The difference between the A640/A710 generation of Canons and the A650 generation is that the latter are capable of shooting continuous movies with file sizes up to 4GB (as opposed to 1GB). The AVI file standard has been updated with new index chunk layouts to allow for such extended files, and this is probably where the problem lies.

The purpose of the index chunks is to allow rapid location of a given timecode in the movie without having to scan through the file to locate it. I'm able to play video files taken with the A650 that are over 2GB in size with other media players and instantly jump to any point in the video. That tells me that the index chunks are OK.

VLC does not use any external codecs, only its own internal ones.

I would indeed suspect that the MJPEG codec VLC uses (which is a fairly unfrequent codec outside of digi cams) may not recognize the index extension from 1GB to 4GB.
Same goes to your media player.."

More Cam-testing proved this theory:
A650
Ixus 860
SX 100/110
TX1
ixus 900

all cams mentioned above have a new feature of "Continuous recording up to 4 GB"
and other tested (older) cams was OK.

[Jean-Baptiste Kempf]

Fill a bug.

[VLC_help]

I don't think has anything to do with MJPEG. I still think that those AVI files are against AVI specs.

An AVI file can be extended beyond 1 GB by placing more than one RIFF chunk in the same file

The current RIFF file format implies a maximum chunk size of 4 GB because the size is stored as a 32-bit value.

http://www.morgan-multimedia.com/download/odmlff2.pdf
And that document is from year 1996. OpenDML AVI doesn't have that 4 GB limit.

[tohtorrent]

so, you think Canon broke the specifications? could be..
I am discussing this on abother board and have info that Canon's avi files have some sort of wrong play-time (and my device is playing only 1 second of the video). Will try to get more information about that, but meanwile you could dig in this direction too. screen: http://www.vosonic.twmail.net/uploads/n ... 7f230e.jpg
any thoughts how can i present this to Canon with more technical way?

Could you please explane the broken specification more, so i could try to contact Canon's support with that?
Tnx.

[VLC_help]

Link you gave isn't working. Specifications aren't broken. The files that those devices create are. Unfortunately it is very common that hardware devices create files that don't follow specifications. And on some cases you cannot even fix the devices because file creation is hardcoded to the chip. On some devices firmware update could help. And I am quite sure that Canon won't fix the issue, but you can ask it from them. Easiest thing is to use Virtualdub to resave the files after you transfer them.