scale with conversion using 2 steps with unittest

a prototype function to implement the yuv to rgb with conversion and scale.
replace with 1 step function in future version, using same API.

R=harryjin@google.com
BUG=libyuv:471

Review URL: https://codereview.chromium.org/1421553016 .

README.chromium

 Name: libyuv
 URL: http://code.google.com/p/libyuv/
-Version: 1536
+Version: 1537
 License: BSD
 License File: LICENSE
 

include/libyuv/scale_argb.h

@@ -35,7 +35,6 @@ int ARGBScaleClip(const uint8* src_argb, int src_stride_argb,
                   int clip_x, int clip_y, int clip_width, int clip_height,
                   enum FilterMode filtering);
 
-// TODO(fbarchard): Implement this.
 // Scale with YUV conversion to ARGB and clipping.
 LIBYUV_API
 int YUVToARGBScaleClip(const uint8* src_y, int src_stride_y,

include/libyuv/version.h

@@ -11,6 +11,6 @@
 #ifndef INCLUDE_LIBYUV_VERSION_H_  // NOLINT
 #define INCLUDE_LIBYUV_VERSION_H_
 
-#define LIBYUV_VERSION 1536
+#define LIBYUV_VERSION 1537
 
 #endif  // INCLUDE_LIBYUV_VERSION_H_  NOLINT

source/scale_argb.cc

@@ -847,6 +847,37 @@ int ARGBScale(const uint8* src_argb, int src_stride_argb,
   return 0;
 }
 
+// Scale with YUV conversion to ARGB and clipping.
+LIBYUV_API
+int YUVToARGBScaleClip(const uint8* src_y, int src_stride_y,
+                       const uint8* src_u, int src_stride_u,
+                       const uint8* src_v, int src_stride_v,
+                       uint32 src_fourcc,
+                       int src_width, int src_height,
+                       uint8* dst_argb, int dst_stride_argb,
+                       uint32 dst_fourcc,
+                       int dst_width, int dst_height,
+                       int clip_x, int clip_y, int clip_width, int clip_height,
+                       enum FilterMode filtering) {
+
+  uint8* argb_buffer = (uint8*)malloc(src_width * src_height * 4);
+  int r;
+  I420ToARGB(src_y, src_stride_y,
+             src_u, src_stride_u,
+             src_v, src_stride_v,
+             argb_buffer, src_width * 4,
+             src_width, src_height);
+
+  r = ARGBScaleClip(argb_buffer, src_width * 4,
+                    src_width, src_height,
+                    dst_argb, dst_stride_argb,
+                    dst_width, dst_height,
+                    clip_x, clip_y, clip_width, clip_height,
+                    filtering);
+  free(argb_buffer);
+  return r;
+}
+
 #ifdef __cplusplus
 }  // extern "C"
 }  // namespace libyuv

unit_test/scale_argb_test.cc

@@ -12,8 +12,10 @@
 #include <time.h>
 
 #include "libyuv/cpu_id.h"
+#include "libyuv/convert.h"
 #include "libyuv/scale_argb.h"
 #include "libyuv/row.h"
+#include "libyuv/video_common.h"
 #include "../unit_test/unit_test.h"
 
 namespace libyuv {
@@ -299,4 +301,156 @@ TEST_SCALETO(ARGBScale, 1280, 720)
 #undef TEST_SCALETO1
 #undef TEST_SCALETO
 
+// Scale with YUV conversion to ARGB and clipping.
+LIBYUV_API
+int YUVToARGBScaleReference2(const uint8* src_y, int src_stride_y,
+                             const uint8* src_u, int src_stride_u,
+                             const uint8* src_v, int src_stride_v,
+                             uint32 src_fourcc,
+                             int src_width, int src_height,
+                             uint8* dst_argb, int dst_stride_argb,
+                             uint32 dst_fourcc,
+                             int dst_width, int dst_height,
+                             int clip_x, int clip_y,
+                             int clip_width, int clip_height,
+                             enum FilterMode filtering) {
+
+  uint8* argb_buffer = (uint8*)malloc(src_width * src_height * 4);
+  int r;
+  I420ToARGB(src_y, src_stride_y,
+             src_u, src_stride_u,
+             src_v, src_stride_v,
+             argb_buffer, src_width * 4,
+             src_width, src_height);
+
+  r = ARGBScaleClip(argb_buffer, src_width * 4,
+                    src_width, src_height,
+                    dst_argb, dst_stride_argb,
+                    dst_width, dst_height,
+                    clip_x, clip_y, clip_width, clip_height,
+                    filtering);
+  free(argb_buffer);
+  return r;
+}
+
+static void FillRamp(uint8* buf, int width, int height, int v, int dx, int dy) {
+  int rv = v;
+  for (int y = 0; y < height; ++y) {
+    for (int x = 0; x < width; ++x) {
+      *buf++ = v;
+      v += dx;
+      if (v < 0 || v > 255) {
+        dx = -dx;
+        v += dx;
+      }
+    }
+    v = rv + dy;
+    if (v < 0 || v > 255) {
+      dy = -dy;
+      v += dy;
+    }
+    rv = v;
+  }
+}
+
+// Test scaling with C vs Opt and return maximum pixel difference. 0 = exact.
+static int YUVToARGBTestFilter(int src_width, int src_height,
+                               int dst_width, int dst_height,
+                               FilterMode f, int benchmark_iterations,
+                               int disable_cpu_flags, int benchmark_cpu_info) {
+  int64 src_y_plane_size = Abs(src_width) * Abs(src_height);
+  int64 src_uv_plane_size = ((Abs(src_width) + 1) / 2) *
+      ((Abs(src_height) + 1) / 2);
+  int src_stride_y = Abs(src_width);
+  int src_stride_uv = (Abs(src_width) + 1) / 2;
+
+  align_buffer_page_end(src_y, src_y_plane_size);
+  align_buffer_page_end(src_u, src_uv_plane_size);
+  align_buffer_page_end(src_v, src_uv_plane_size);
+
+  int64 dst_argb_plane_size = (dst_width) * (dst_height) * 4LL;
+  int dst_stride_argb = (dst_width) * 4;
+  align_buffer_page_end(dst_argb_c, dst_argb_plane_size);
+  align_buffer_page_end(dst_argb_opt, dst_argb_plane_size);
+  if (!dst_argb_c || !dst_argb_opt || !src_y || !src_u || !src_v) {
+    printf("Skipped.  Alloc failed " FILELINESTR(__FILE__, __LINE__) "\n");
+    return 0;
+  }
+  // Fill YUV image with continuous ramp, which is less sensitive to
+  // subsampling and filtering differences for test purposes.
+  FillRamp(src_y, Abs(src_width), Abs(src_height), 128, 1, 1);
+  FillRamp(src_u, (Abs(src_width) + 1) / 2, (Abs(src_height) + 1) / 2, 3, 1, 1);
+  FillRamp(src_v, (Abs(src_width) + 1) / 2, (Abs(src_height) + 1) / 2, 4, 1, 1);
+  memset(dst_argb_c, 2, dst_argb_plane_size);
+  memset(dst_argb_opt, 3, dst_argb_plane_size);
+
+  YUVToARGBScaleReference2(src_y, src_stride_y,
+                           src_u, src_stride_uv,
+                           src_v, src_stride_uv,
+                           libyuv::FOURCC_I420,
+                           src_width, src_height,
+                           dst_argb_c, dst_stride_argb,
+                           libyuv::FOURCC_I420,
+                           dst_width, dst_height,
+                           0, 0, dst_width, dst_height,
+                           f);
+
+  for (int i = 0; i < benchmark_iterations; ++i) {
+    YUVToARGBScaleClip(src_y, src_stride_y,
+                       src_u, src_stride_uv,
+                       src_v, src_stride_uv,
+                       libyuv::FOURCC_I420,
+                       src_width, src_height,
+                       dst_argb_opt, dst_stride_argb,
+                       libyuv::FOURCC_I420,
+                       dst_width, dst_height,
+                       0, 0, dst_width, dst_height,
+                       f);
+  }
+  int max_diff = 0;
+  for (int i = 0; i < dst_height; ++i) {
+    for (int j = 0; j < dst_width * 4; ++j) {
+      int abs_diff = Abs(dst_argb_c[(i * dst_stride_argb) + j] -
+                         dst_argb_opt[(i * dst_stride_argb) + j]);
+      if (abs_diff > max_diff) {
+        printf("error %d at %d,%d c %d opt %d",
+               abs_diff,
+               j, i,
+               dst_argb_c[(i * dst_stride_argb) + j],
+               dst_argb_opt[(i * dst_stride_argb) + j]);
+        EXPECT_LE(abs_diff, 40);
+        max_diff = abs_diff;
+      }
+    }
+  }
+
+  free_aligned_buffer_page_end(dst_argb_c);
+  free_aligned_buffer_page_end(dst_argb_opt);
+  free_aligned_buffer_page_end(src_y);
+  free_aligned_buffer_page_end(src_u);
+  free_aligned_buffer_page_end(src_v);
+  return max_diff;
+}
+
+TEST_F(LibYUVScaleTest, YUVToRGBScaleUp) {
+  int diff = YUVToARGBTestFilter(benchmark_width_, benchmark_height_,
+                                 benchmark_width_ * 3 / 2,
+                                 benchmark_height_ * 3 / 2,
+                                 libyuv::kFilterBilinear,
+                                 benchmark_iterations_,
+                                 disable_cpu_flags_, benchmark_cpu_info_);
+  EXPECT_LE(diff, 10);
+}
+
+TEST_F(LibYUVScaleTest, YUVToRGBScaleDown) {
+  int diff = YUVToARGBTestFilter(benchmark_width_ * 3 / 2,
+                                 benchmark_height_ * 3 / 2,
+                                 benchmark_width_, benchmark_height_,
+                                 libyuv::kFilterBilinear,
+                                 benchmark_iterations_,
+                                 disable_cpu_flags_, benchmark_cpu_info_);
+  EXPECT_LE(diff, 10);
+}
+
+
 }  // namespace libyuv