Video Low Image Quality or Excessively Large Size

[michaelmyc]

Actions before raising this issue

• I searched the existing issues and did not find anything similar.
• I read/searched the docs

Steps to Reproduce

1. Upload a video with "zip chunks" enabled, compression set to 100% (do not compress)
2. Video playback is laggy due to large chunk sizes (a 5MB 1080p H265 video would have a chunk size of 2+MB whereas each chunk only accounts for a few dozen frames), but image quality is good
3. Upload a video with "zip chunks" disabled, compression set to 100% (do not compress)
4. Video playback is decent but the image quality is sub-par
5. Serve the video as a file and visit that URL (on exactly the same server with the same networking conditions), the streaming playback is extremely smooth and the image quality is good

Expected Behavior

Video quality should not be degraded in non "zip chunks" mode.

Possible Solution

Maybe, just use the same streaming method that the default video player in Chrome uses for non zip chunks videos?

Also, zip chunks seems to be huge, maybe we can have some method of optimizing it, but I'm not very familiar with the implementation details so I don't have good suggestions here.

Context

Video directly served as file:

Video in CVAT without zip chunks:

Environment

![image](https://github.com/user-attachments/assets/e6af1941-9194-4ece-9aed-37561b35cf87)