* craft-video: VP8 key-frame encoder (`vp8-encode` feature)
Moves effectcraft's effectcraft-vp8enc here: the lossy picture of a WebP image
or animation frame, written from RFC 6386. Rate-distortion choice between the
16x16 and B_PRED intra modes, per-frame token probability updates, loop filter
level from the quantizer.
`vp8` now turns on `vp8-decode` and `vp8-encode`, as `vp9` does; the decoder's
tests and examples require `vp8-decode`. The tests decode the encoder's frames
with this crate's decoder: with the loop filter off it reproduces the encoder's
reconstruction exactly.
* craft-webp: animated WebP writer, lossy through craft-video (feature vp8)
The VP8X/ANIM/ANMF container around frames another encoder made (lossy with
an alpha plane, or lossless VP8L), and with feature vp8 whole lossy
animations from RGBA frames through craft-video's VP8 key-frame encoder.
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Co-authored-by: Justin A. Wilson <waj334@gmail.com>
Like craft-gif's: every frame composited, a still as one frame, canvas cap
checked from the headers, stops at the frame or byte limit or at a damaged
frame and says which, optional merging of identical frames.
The WebP container code the apps wrote themselves: EffectCraft's chunk walk
(canvas, alpha, animation frames and their durations) and PhotoCraft's RIFF
writer around an encoded VP8 frame with alpha, ICC, EXIF and XMP chunks. The
codecs are not part of the crate.
Dylan M. Taylor