Commit Graph

1 Commits

Author SHA1 Message Date
DRC
f3a8684cd1 SSE2 SIMD implementation of Huffman encoding
Full-color compression speedups relative to libjpeg-turbo 1.4.2:

2.8 GHz Intel Xeon W3530, Linux, 64-bit:  2.2-18% (avg. 9.5%)
2.8 GHz Intel Xeon W3530, Linux, 32-bit:  10-25% (avg. 17%)

2.3 GHz AMD A10-4600M APU, Linux, 64-bit:  4.9-17% (avg. 11%)
2.3 GHz AMD A10-4600M APU, Linux, 32-bit:  8.8-19% (avg. 15%)

3.0 GHz Intel Core i7, OS X, 64-bit:  3.5-16% (avg. 10%)
3.0 GHz Intel Core i7, OS X, 32-bit:  4.8-14% (avg. 11%)

2.6 GHz AMD Athlon 64 X2 5050e:
Performance-neutral (give or take a few percent)

Full-color compression speedups relative to IPP:

2.8 GHz Intel Xeon W3530, Linux, 64-bit:  4.8-34% (avg. 19%)
2.8 GHz Intel Xeon W3530, Linux, 32-bit:  -19%-7.0% (avg. -7.0%)

Refer to #42 for discussion.  Numerous other approaches were attempted,
but this one proved to be the most performant across all platforms.

This commit also fixes #3 (works around, really-- the clang-compiled version
of jchuff.c still performs 20% worse than its GCC-compiled counterpart, but
that code is now bypassed by the new SSE2 Huffman algorithm.)

Based on:
2cb4d41330
36c94e050d
2016-01-12 03:03:49 -06:00