VSE thumbnails improvements #91618

New Issue

Richard Antalik · 2021-09-23T00:58:11+02:00

Richard Antalik commented

2021-09-23 00:58:11 +02:00

Check if reusing strip hash used by rendering job speeds up initialization with large number of strips. if it doesn't, fix it anyway. (b534806ecb) Note: it wasn't initialization that caused freezing, it was rather strip anim freeing, reusing ghash seems to have no impact on performance.
To speed up loading, Check strategy to render "guaranteed" set of thumbnails. Especially if cache can be shared this could help a lot. (3a898db363) Note: better strategy seems to be other way around as far as performance goes.
Make first (and last) thumbnail reflect actual handle position. (29b9187b32) Note: Only first image is updated, though it's possilbe to update last one too.
Change cache so thumbnail (and possibly raw) types are keyed by path to file and disregard various context settings and Sequence pointer. Front-end should stay same. (D12771)
- There are rabbitholes like effect strips producing raw images and scene strips rendering at "host" scene resolution so simple string key is probably not enough.
- Added complexity is, that all cache types per frame should be invalidated at once, otherwise prefetch doesn't work and issues like that.
- Above points don't quite apply to thumbnails, but there are issues of this type in general. For example if we would implement downscaling for movies, first point will apply.

- [x] Check if reusing strip hash used by rendering job speeds up initialization with large number of strips. if it doesn't, fix it anyway. (b534806ecb) Note: it wasn't initialization that caused freezing, it was rather strip `anim` freeing, reusing ghash seems to have no impact on performance. - [x] To speed up loading, Check strategy to render "guaranteed" set of thumbnails. Especially if cache can be shared this could help a lot. (3a898db3638d) Note: better strategy seems to be other way around as far as performance goes. - [x] Make first (and last) thumbnail reflect actual handle position. (29b9187b327c) Note: Only first image is updated, though it's possilbe to update last one too. - Change cache so thumbnail (and possibly raw) types are keyed by path to file and disregard various context settings and Sequence pointer. Front-end should stay same. ([D12771](https://archive.blender.org/developer/D12771)) - There are rabbitholes like effect strips producing raw images and scene strips rendering at "host" scene resolution so simple string key is probably not enough. - Added complexity is, that all cache types per frame should be invalidated at once, otherwise prefetch doesn't work and issues like that. - Above points don't quite apply to thumbnails, but there are issues of this type in general. For example if we would implement downscaling for movies, first point will apply.

Richard Antalik commented

2021-09-23 00:58:11 +02:00

Changed status from 'Needs Triage' to: 'Confirmed'