problems on ubuntu 18.04

[wr0112358]

I tried the prebuilt release from sourceforge: only first frame of video is shown, no frame update when seeking through video or when playing back. Both System and Super Build result in the following error when trying to open a video file: invalid data found when processing input

I tried to fix this behavior by inserting "av_register_all();" into the function: Plugin::_init Now playing back works. As soon as I pause the playback or seek through the video the displayed frame freezes and is not updated anymore.

Are specific versions of the used ffmpeg libraries needed?

[darbyjohnston]

Hi! Good call on the "av_register_all()" function, I'll add that to the code. Unfortunately there are a number of issues with movie playback right now, which is probably what you are running into. I'm in the process of rewriting the playback engine to fix these though I'm doing it as a separate project which I will merge back into DJV for the next release. If you are interested in checking it out here's the link: https://github.com/darbyjohnston/tlRender

Also here is a collection of high-res movies I've been testing it on: https://github.com/darbyjohnston/otio-oc-examples

[wr0112358]

Hi, interesting project! I was searching for a tool to annotate rare classes in a high fps dataset for machine learning in a medical environment. Most players don't do this very well. A player that can display the results of such data algorithms in a timeline below a video would be very useful. E.g. plot one or more scalars per frame, or one or more categorical variables per frame.

[darbyjohnston]

I'm trying to develop the "tlRender" project as a toolkit for building playback applications, you might be able to use some of it's components for a custom application like you describe. I've added Qt widgets for a timeline slider, playback controls, and timeline viewport. The timeline slider could be a good example for how to write a widget for displaying the data algorithms.

The performance seems to be fairly good, the example Qt application can play back most of the movies in the link above, including 4K@60FPS. The playback is backed by a memory cache so frame by frame stepping is really fast. It solves most of the playback issues that DJV has, and I hope to integrate the code back into DJV soon.