Move alpha endpoint refinement into the alpha endpoint optimization thread

Browse Source

This change improves compression speed when using alpha channel.

Explanation:
As the alpha endpoint refinement does not depend on the alpha selector codebook computation, it can be safely moved into the alpha endpoint optimization thread.

Testing:
The modified algorithm has been tested on the Kodak test set using 64-bit build with default settings (running on Windows 10, i7-4790, 3.6GHz). All the decompressed test images are identical to the images being compressed and decompressed using original version of Crunch.

[Compressing Kodak set without mipmaps]
Original: 1582222 bytes / 28.912 sec
Modified: 1494501 bytes / 24.128 sec
Improvement: 5.54% (compression ratio) / 16.55% (compression time)

[Compressing Kodak set with mipmaps]
Original: 2065243 bytes / 36.985 sec
Modified: 1945365 bytes / 31.741 sec
Improvement: 5.80% (compression ratio) / 14.18% (compression time)

...

This commit is contained in:

Alexander Suvorov

2017-05-12 14:06:53 +02:00

parent 9c289fc621

commit 1ef829ed6f

2 changed files with 40 additions and 154 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download Patch File Download Diff File Expand all files Collapse all files

bin/crunch_x64.exe

BIN

Binary file not shown.