Imagemagick ffmpeg delegate error

[georgem]

I am trying to extract the first frame from an mp4 video. I am running the following command:

/usr/local/bin/convert '/home/joycem6/media/upload/shambala.mp4[1]' -resize 350X450 -quality 80 -colorspace RGB '/home/joycem6/media/upload/preview/preview_498d9da8a455e.jpg'

I get this error:

convert: Delegate failed `"ffmpeg" -v -1 -i "%i" -vcodec pam -an -f rawvideo -y "%u0.pam" 2> "%Z"' @ delegate.c/InvokeDelegate/1015. convert: missing an image filename `/home/joycem6/media/upload/preview/preview_498d9da8a455e.jpg' @ convert.c/ConvertImageCommand/2710.

My web host says the problem is the missing file, but the file mentioned is the output file which, of course, won't exist until the command has completed successfully. My assumption is that "delegate failed" is the real error. What is the real error and how do I (or they) fix it? The web host says that ffmpeg is installed on the server.

[anthony]

Can you write to the directory?

as you are using a ISP it sounds like you may be doing from from a web server script. The web server usally runs as a completely different user to the normal account, and as such may not have write access by default (this is on purpose as a security measure).

Try writing the file into /tmp and make sure you clean up afterward or the ISP may not be too happy.

[georgem]

Hi Anthony,
Yes, I can write to the directory. You're right, I am shelling out from a PHP script. I use imagemagick to create other jpegs to the same directory with no problem.
George

[anthony]

Ok have you redirected and looked at any errors the command may have produced?

[georgem]

Yes, I did redirect. The error I received is what I put in my first post:

convert: Delegate failed `"ffmpeg" -v -1 -i "%i" -vcodec pam -an -f rawvideo -y "%u0.pam" 2> "%Z"' @ delegate.c/InvokeDelegate/1015. convert: missing an image filename `/home/joycem6/media/upload/preview/preview_498d9da8a455e.jpg' @ convert.c/ConvertImageCommand/2710.

[anthony]

What version of IM are you using.

I remember reporting and having an error fixed where a delegate recieved the wrong filename. This was fixed for IM 6.4.3-7