commit ef5e0288ce5e28b9a3018034309582dd227fc31d
author Nigel Tao <nigeltao@golang.org> Mon Oct 20 10:46:12 2014 +1100
committer Nigel Tao <nigeltao@golang.org> Mon Oct 20 10:46:12 2014 +1100
tree 2031e6b94d2710bfd257036d7f442429008fe444
parent d354b8dda92f0cd601f904c6d8643d4cf1034181

go.image/webp: implement lossy-with-alpha.

This fixes all three lossy_alpha*.webp conformance tests.

The test data was generated by cwebp/dwebp version 0.4.1:
cwebp yellow_rose.png -o yellow_rose.lossy-with-alpha.webp
dwebp yellow_rose.lossy-with-alpha.webp -pgm -o tmp.pgm
convert tmp.pgm yellow_rose.lossy-with-alpha.webp.nycbcra.png

LGTM=pascal.massimino, r
R=r, pascal.massimino
CC=golang-codereviews
https://golang.org/cl/154350043