Step thru full color test by increments of 5 for better test speed.

Full color test is the slowest of the unittests, and not catching any
additional bugs at the moment.  Step thru range of 0 to 255 in steps of
5 to speed up the test.  255 is 3 * 5 * 17, so any of those primes would
hit 0 and 255 exactly.

Was LibYUVColorTest.TestFullYUV (896 ms)
Now LibYUVColorTest.TestFullYUV (212 ms)

TBR=kjellander@chromium.org
Bug: libyuv:736
Test: LibYUVColorTest.TestFullYUV
Change-Id: I5b55fb07ada0dc7bdc3c3c20569d36bf09bb3804
Reviewed-on: https://chromium-review.googlesource.com/672064
Commit-Queue: Frank Barchard <fbarchard@google.com>
Reviewed-by: Frank Barchard <fbarchard@google.com>

README.chromium

 Name: libyuv
 URL: http://code.google.com/p/libyuv/
-Version: 1670
+Version: 1671
 License: BSD
 License File: LICENSE
 

include/libyuv/version.h

@@ -11,6 +11,6 @@
 #ifndef INCLUDE_LIBYUV_VERSION_H_
 #define INCLUDE_LIBYUV_VERSION_H_
 
-#define LIBYUV_VERSION 1670
+#define LIBYUV_VERSION 1671
 
 #endif  // INCLUDE_LIBYUV_VERSION_H_

source/cpu_id.cc

@@ -124,7 +124,7 @@ void CpuId(int eax, int ecx, int* cpu_info) {
 int GetXCR0() {
   int xcr0 = 0;
 #if defined(_MSC_FULL_VER) && (_MSC_FULL_VER >= 160040219)
-  xcr0 = (int) _xgetbv(0);  // VS2010 SP1 required.  NOLINT
+  xcr0 = (int)_xgetbv(0);  // VS2010 SP1 required.  NOLINT
 #elif defined(__i386__) || defined(__x86_64__)
   asm(".byte 0x0f, 0x01, 0xd0" : "=a"(xcr0) : "c"(0) : "%edx");
 #endif  // defined(__i386__) || defined(__x86_64__)

unit_test/color_test.cc

@@ -471,21 +471,22 @@ static void PrintHistogram(int rh[256], int gh[256], int bh[256]) {
   printf("\n");
 }
 
+// Step by 5 on inner loop goes from 0 to 255 inclusive.
+// Set to 1 for better converage.  3, 5 or 17 for faster testing.
+#define FASTSTEP 5
 TEST_F(LibYUVColorTest, TestFullYUV) {
-  int rh[256] =
-      {
+  int rh[256] = {
       0,
-      },
-      gh[256] =
-          {
+  };
+  int gh[256] = {
       0,
-          },
-      bh[256] = {
+  };
+  int bh[256] = {
       0,
   };
   for (int u = 0; u < 256; ++u) {
     for (int v = 0; v < 256; ++v) {
-      for (int y2 = 0; y2 < 256; ++y2) {
+      for (int y2 = 0; y2 < 256; y2 += FASTSTEP) {
         int r0, g0, b0, r1, g1, b1;
         int y = RANDOM256(y2);
         YUVToRGBReference(y, u, v, &r0, &g0, &b0);
@@ -503,20 +504,18 @@ TEST_F(LibYUVColorTest, TestFullYUV) {
 }
 
 TEST_F(LibYUVColorTest, TestFullYUVJ) {
-  int rh[256] =
-      {
+  int rh[256] = {
       0,
-      },
-      gh[256] =
-          {
+  };
+  int gh[256] = {
       0,
-          },
-      bh[256] = {
+  };
+  int bh[256] = {
       0,
   };
   for (int u = 0; u < 256; ++u) {
     for (int v = 0; v < 256; ++v) {
-      for (int y2 = 0; y2 < 256; ++y2) {
+      for (int y2 = 0; y2 < 256; y2 += FASTSTEP) {
         int r0, g0, b0, r1, g1, b1;
         int y = RANDOM256(y2);
         YUVJToRGBReference(y, u, v, &r0, &g0, &b0);
@@ -532,6 +531,7 @@ TEST_F(LibYUVColorTest, TestFullYUVJ) {
   }
   PrintHistogram(rh, gh, bh);
 }
+#undef FASTSTEP
 
 TEST_F(LibYUVColorTest, TestGreyYUVJ) {
   int r0, g0, b0, r1, g1, b1, r2, g2, b2;