webp-lossless-bitstream-spec: improve 'small' color table stmt

this is defined earlier as 16 or fewer unique values

based on comments from:
https://datatracker.ietf.org/doc/draft-zern-webp/ballot/#draft-zern-webp_lars-eggert

Bug: webp:448
Change-Id: If9e18e5aaec3641e477c2bb68dacc0a4fd029cfb
This commit is contained in:
James Zern 2022-09-29 19:03:03 -07:00
parent dfd32e4592
commit 57101d3fc5

View File

@ -566,7 +566,7 @@ pixels are bundled into a single pixel. The pixel bundling packs several
respectively. Pixel bundling allows for a more efficient joint respectively. Pixel bundling allows for a more efficient joint
distribution entropy coding of neighboring pixels, and gives some distribution entropy coding of neighboring pixels, and gives some
arithmetic coding-like benefits to the entropy code, but it can only be arithmetic coding-like benefits to the entropy code, but it can only be
used when there are a small number of unique values. used when there are 16 or fewer unique values.
`color_table_size` specifies how many pixels are combined: `color_table_size` specifies how many pixels are combined: