Video Thumbnails

We are having trouble getting Omeka to generate thumbnails for video. I think this is due to the fact that our imagemagick installation is having a problem interfacing with ffmpeg, which (i think?) is required for imagemagic to create video thumbnails. Can omeka be set up to interface directly with ffmpeg to create video thumbnails? Or do I have to tropubleshoot IM/ffmpeg? Or is there an alternate way of getting Imagemagick to make video thumbnails? I’ll take whatever help and suggestions people can offer.

That diagnosis sounds right to me. But, different versions of imagemagick produce different results, so it it’s possible to just upgrade imagemagick (and/or ffmpeg), that might be the first thing to try.

As an alternate, you could try using the GD or IMagick strategies for derivative images. Here’s how to configure different derivative strategies.

Usually all that’s necessary is to have both imagemagick and ffmpeg installed and things “just work.” In terms of troubleshooting, SSHing to the server and running identify on a test video file and seeing what happens is probably the easiest option.

Despite the fact that both are installed on the server, ffmpeg and IM are not playing well together. When I try to invoke any of IMs video processing options from the command line, I get this:

delegate failed `“ffmpeg” -v -1 -vframes %S -i “%i” -vcodec pam -an -f rawvideo -y “%u.pam” 2> “%Z”’ @ error/delegate.c/InvokeDelegate/1049.

After looking at the documentation for both systems, what this looks like is that the invocation of ffmpeg from IM is failing. Perhaps the command syntax is wrong, although if that’s the case, I’ve no idea how to fix it in the delegate file. I’ve tried uninstalling and re-installing imagemagick, no joy. I know ffmpeg is installed and working-I’ve invoked it from the command line directly with no problems (which is why I’m asking about making Omeka interface with it directly).

Do GD and Imagick rely on ffmpeg? Or are they self contained? I’m stretching my knowledge of unix here and am not super comfortable debugging strings of helper program dependencies.

Is it possible to upload our own thumbnails using the csv import plugin? If so, I can probably write a script to auto-generate thumbnails using ffmpeg, and we can load them when we do batch ingests.

The CSV Import idea won’t work, since it still goes through the same ingest process, creating the derivatives the same way as uploading a file.

Another question that might help – What is the video format you are uploading? And, does the error occur with all video formats?

Are there any more lines to the error message other than what you posted? If ffmpeg is actually running but hitting an error itself, there should be some error explaining that that also gets printed alongside what you’ve got here.

If ffmpeg is installed and works when invoked with that name on the command line, the most likely issue is that there’s a version mismatch between the two: ImageMagick is producing a command with a syntax that doesn’t work with the version of ffmpeg you’ve got. You can run convert -version and ffmpeg -version to see what versions of each you have.

As for using GD, it’s simply not going to work with videos at all. GD has the benefit of being bundled with PHP and therefore highly available, but the price is that it has a far more restrictive set of file types it can work with than ImageMagick does.

Imagick is just using ImageMagick under the hood, so it also depends on ffmpeg to do anything video-related.

Doing thumbnailing with ffmpeg directly, or at least more directly, is possible, but there’s nothing in Omeka to do it for you, and it’s probably not worth the trouble vs. getting ImageMagick to work.

Looks like it was a version mismatch problem-we installed a different version of ImageMagick and it seems to be working now.

Hi, could I ask which specific versions of ImageMagick and ffmpeg you got to work together?

Also, we’re on Ubuntu 14.04.2 LTS and it looks like we’d need to upgrade to 15.04 to install ffmpeg:

Could I ask which OS and version you’re using?