ChangeLog: Mention ARM64 Huffman & adj perf claims
diff --git a/ChangeLog.txt b/ChangeLog.txt
index 505f766..ccff54f 100644
--- a/ChangeLog.txt
+++ b/ChangeLog.txt
@@ -67,20 +67,32 @@
or regression testing, SIMD-accelerated Huffman encoding can be disabled by
setting the JSIMD_NOHUFFENC environment variable to 1.
-[13] Added SIMD acceleration for Huffman encoding on NEON-capable ARM 32-bit
-platforms. This speeds up the compression of full-color JPEGs by about 30% on
-average on a Cortex-A9 core (iPhone 4S) and by about 6-7% on average on
-Cortex-A53 and Cortex-A57 cores. For the purposes of benchmarking or
-regression testing, SIMD-accelerated Huffman encoding can be disabled by
-setting the JSIMD_NOHUFFENC environment variable to 1.
-
-[14] Added ARM 64-bit (ARMv8) NEON SIMD implementations of the commonly-used
+[13] Added ARM 64-bit (ARMv8) NEON SIMD implementations of the commonly-used
compression algorithms (including the slow integer forward DCT and h2v2 & h2v1
downsampling algorithms, which are not accelerated in the 32-bit NEON
implementation.) This speeds up the compression of full-color JPEGs by about
75% on average on a Cavium ThunderX processor and by about 2-2.5x on average on
Cortex-A53 and Cortex-A57 cores.
+[14] Added SIMD acceleration for Huffman encoding on NEON-capable ARM 32-bit
+and 64-bit platforms.
+
+For 32-bit code, this speeds up the compression of full-color JPEGs by about
+30% on average on a typical iOS device (iPhone 4S, Cortex-A9) and by about 6-7%
+on average on a typical Android device (Nexus 5X, Cortex-A53 and Cortex-A57),
+relative to libjpeg-turbo 1.4.x. Note that the larger speedup under iOS is due
+to the fact that iOS builds use LLVM, which does not optimize the C Huffman
+encoder as well as GCC does.
+
+For 64-bit code, NEON-accelerated Huffman encoding speeds up the compression of
+full-color JPEGs by about 40% on average on a typical iOS device (iPhone 5S,
+Apple A7) and by about 7-8% on average on a typical Android device (Nexus 5X,
+Cortex-A53 and Cortex-A57), in addition to the speedup described in [13] above.
+
+For the purposes of benchmarking or regression testing, SIMD-accelerated
+Huffman encoding can be disabled by setting the JSIMD_NOHUFFENC environment
+variable to 1.
+
[15] pkg-config (.pc) scripts are now included for both the libjpeg and
TurboJPEG API libraries on Un*x systems. Note that if a project's build system
relies on these scripts, then it will not be possible to build that project
