MATLAB Central Newsreader - mmreader reaching premature EOF on Quicktime files

Re: mmreader reaching premature EOF on Quicktime files

Kevin Christie — Tue, 13 May 2008 15:03:04 -0400

Thanks,

I am already in contact with the support people to work on
this issue.

Kevin Christie
kwchrist@uiuc.edu

Bob <rbemis@mathworks.com> wrote in message
<g0afsb$nf1$2@fred.mathworks.com>...
> You should contact MathWorks support.
> http://www.mathworks.com/support/contact_us/index.html
>
> Hopefully you can share the problem file so it can be
investigated. It
> could be a MATLAB bug or a corrupt AVI file.
>
> Cheers
> Bob

Re: mmreader reaching premature EOF on Quicktime files

Bob — Mon, 12 May 2008 22:20:58 -0400

You should contact MathWorks support.
http://www.mathworks.com/support/contact_us/index.html

Hopefully you can share the problem file so it can be investigated. It
could be a MATLAB bug or a corrupt AVI file.

Cheers
Bob

mmreader reaching premature EOF on Quicktime files

Kevin Christie — Fri, 09 May 2008 22:56:03 -0400

I'm currently using mmreader to open video files of animal
movements to perform tracking and analysis. I'm using the
latest version of MATLAB R2008a on a Power Mac with OSX. My
video files are 640x480 encoded in QT with H.265 using the
Compressor program with a framerate of 29.97.

The problem I'm having is that sporadically when I attempt
to grab a frame with the statement:

image = read(movie_obj, frame_index);

sometimes I get an error claiming that mmreader attempted to
read a frame beyond the end of the movie, which isn't true.
Incrementing the index to frame_index + 1 or frame_index -1
works perfectly.

For a given movie file, it seems 1 or 2 frames per every
1000 or so will not work. I've loaded the movie file into
multiple video editing programs, including Adobe Premiere
and Final Cut Pro, and these have no problems reading the
'problem' frames - the data exists, but for some reason,
mmreader cannot read it.

Has anyone else had problems like this? I'm not familiar
with the internals of how video data and frames are
represented in .mov files. I'm not sure of the 29.97 fps
value may have something to do with it - but I don't see why
the framerate would be necessary to the read() function. It
is important that I can solve this issue - conversion to
another file format is not an option, I have GBs of video
and QT has the best file size/video clarity ratio of any of
the formats I've tested.

Kevin Christie