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quietvoid / dovi_tool

dovi_tool is a CLI tool combining multiple utilities for working with Dolby Vision.
MIT License
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variable aspect ratio (with crop) #151

Closed mylesmacrae closed 2 years ago

mylesmacrae commented 2 years ago

Hi, I'm trying to preserve DV on a video that switches between 1.9:1 (70/70 top and bottom bars) and 2.39:1 (278/278 top and bottom bars). The video has been transcoded to crop to the widest frame, so the next challenge is preparing the RPU data accurately.

Would -c take care of this usecase? Or would I need to use editor mode to set a new active area? Or is there some other workflow I should consider?

quietvoid commented 2 years ago

You need to edit the RPU, see example: https://github.com/quietvoid/dovi_tool/blob/main/assets/editor_examples/active_area.json Transitioning frames from one AR to the other should be using the same L5 metadata as the pre-transition AR.

In your use case you would have to define two presets, and add edits for every continuous shot with the corresponding letterbox bars preset.

mylesmacrae commented 2 years ago

Thanks! Would the new active areas be relative to the new output video size? i.e 0/0/0/0 for the 1.9 sequences, 208/0/208/0 for the 2.39 sequences? Or would I keep the old values?

quietvoid commented 2 years ago

Yes, they are relative to the target output video. You can then use "crop": true and only use one preset for 208/0/208/0 for the edits.

mylesmacrae commented 2 years ago

awesome. thank you for the pointers!