Talkinghead next5

[Technologicat]

The backend changes for talkinghead are nearing completion for now. Here's the next PR.

Changelog:

• Microsway (character pose jitter) is now framerate-independent, always updated at 25 FPS.
• All postprocessor effects are now framerate-independent.
  • This works by giving the filters a (float-valued) normalized frame number that always runs at 25 FPS, regardless of the actual render FPS. For best accuracy, the number is computed without accumulation.
• Add a simple crop filter.
  • New animator config keys crop_left, crop_right, crop_top, crop_bottom. Float, given in units where both the width and the height of the full sprite are 2.0. For example, "crop_left": 0.5 cuts away 25% of the image from the left. Default is no crop.
  • Cutting out the blank space around the character improves postprocessor performance. The poser isn't affected because it always works at 512x512 (so we must crop after posing).
  • As of this writing, this doesn't yet allow positioning the character nearer the screen edge in MovingUI mode. Seems something in the frontend is preventing that.
• Support server-default animator/postprocessor configuration, SillyTavern-extras/talkinghead/animator.json.
  • This is preferable over per-character config for things like target_fps.
  • Examples in README updated.
• The render time reported in the extras server console now excludes postprocessing time.
  • Total render time per frame = reported render time + reported postproc time.
• Postproc filters affecting brightness (noise, scanlines) now have variants that do not affect translucency.
  • New lumanoise filter, sister to alphanoise.
  • scanlines now has a channel parameter. Set it to "A" for alpha, or "Y" for luminance (new default).
  • Implemented via RGB<->YUV conversion.
• Update README, including the changes mentioned in this changelog, and the input from discussion in talkinghead changes TODO list #206.

Now there's still a lot of frontend work and documentation updates to do, as well as making some example characters to go with this...

[Technologicat]

Thanks for the merge!