Suggested Improvement to Importing incontiguous (discontinuous) image sequences with missing frames

[patwooky]

I am not sure if this is an issue or an intended way the software handles image sequences that are not continuous.

As a VFX artist, I render images in frames as a sequence of images. As I render them, frames are added to the sequence. Say I have 600 frames, I start rendering and get 10 frames. I get a sequence of 10 frames in the player. I can play it and see the results of 10 frames. I wait another 2 minutes, I get another 10 frames. There is no way to extend the frame range, so the only way I can load in 20 continuous frame is to close the window that contains the 10 frames, then open another sequence containing the 20 frames. As more frames are added to the file sequence I have to continuously repeat closing and opening of sequences.

The next option for me would be to try and render the final frame 600, thus setting an upper bound for the sequence of images. I wanted to see how DJV handles missing frames in a sequence. I was expecting to see a timeline spanning 1 to 600, with error reading the in-between images. In this way I can avoid repeatedly re-opening the sequence described previously. I can have the timeline with the correct image range defined only once, and wait for the individual frames of images to written to disk as I reload those frames.

So in my test I had 20 rendered frames. I went to render frames 400-403, and then the last frame at frame 600. In the file > Open dialogue DJV listed the sequence of images as a single item:
1-20, 400-403, 600

When I click on that to open it, DJV first puts the contiguous range of 1-20 in the first 20 frames of the viewer timeline.
Then on frame 21 to frame 24 in the playback timeline, DJV labels it frame 400 - 403.
Finally on frame 25 in the playback timeline DJV labels that frame as 600.

This was a surprise to me. I can understand how some people would like to see their completed files this way. However, coming from my intention to have placeholder frames to hold out the sequence, it demanded that I keep closing and reloaded the same sequence over and over again as new files have completed the rendering.

Thus I am wondering if there can be some configuration or options how an incomplete sequence of files can be handled. These options can include:

• Being able to enter the intended frame range of a file sequence instead of using the last file as the last frame of the sequence, or being able to specify an in/out point after loading the image sequence, to beyond the first and last frame of the existing files on disk.
• The choice to handle incontiguous files sequence with missing frames in the 2 ways
  • the current way where existing files are placed back-to-back in the playback timeline
  • padding the timeline with empty frames that read error, until the files become available

I would love to find out about any workarounds with the current behaviour if it can help me avoid loading the image sequence again and again.

Finally, here is a screenshot of the File Browser showing what I have described:

Thank you so much for the time you have put into developing this amazing software. I really appreciate it!