From: José Fonseca <jose.r.fonseca@gmail.com>
Date: Fri, 16 Mar 2012 11:39:14 +0000 (+0000)
Subject: Use Z_BEST_SPEED on PNG compression.
X-Git-Url: https://git.cworth.org/git?a=commitdiff_plain;h=0d06c46f764ba80106d6f4ad9fb4560c98872155;p=apitrace

Use Z_BEST_SPEED on PNG compression.

Otherwise the CPU becomes a major bottleneck when dumping even a modest number of frames.
---

diff --git a/common/image_png.cpp b/common/image_png.cpp
index a65577a..cc6d3f2 100644
--- a/common/image_png.cpp
+++ b/common/image_png.cpp
@@ -40,6 +40,9 @@
 namespace image {
 
 
+static const int png_compression_level = Z_BEST_SPEED;
+
+
 bool
 Image::writePNG(const char *filename) const {
     FILE *fp;
@@ -89,7 +92,7 @@ Image::writePNG(const char *filename) const {
     png_set_IHDR(png_ptr, info_ptr, width, height, 8, color_type,
         PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
 
-    png_set_compression_level(png_ptr, Z_DEFAULT_COMPRESSION);
+    png_set_compression_level(png_ptr, png_compression_level);
 
     png_write_info(png_ptr, info_ptr);
 
@@ -275,7 +278,7 @@ bool writePixelsToBuffer(unsigned char *pixels,
                  type, PNG_INTERLACE_NONE,
                  PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
 
-    png_set_compression_level(png_ptr, Z_DEFAULT_COMPRESSION);
+    png_set_compression_level(png_ptr, png_compression_level);
 
     png_write_info(png_ptr, info_ptr);