Add tentative I422Rotate.

When doing 90 or 270 degrees rotation we need to do a rotate&scale of the UV planes, as there are no helper optimized functions to do this, we use the Y plane as temporal memory and perform each of the transforms independently:

First U plane is rotated, putting the result in the Y plane. After the rotation, the output has double the samples horizontally and half the samples vertically, so it is scaled into the final U plane. Same process is done with the V plane.

Last the Y plane that can be just rotated without scaling.

It would be great to have an optimized version for this, but maybe this is helpfull for triggering the discussions.

Bug: libyuv:926
Change-Id: I188af103c4d0e3f9522021b4bf2b63c9d5de8b93
Reviewed-on: https://chromium-review.googlesource.com/c/libyuv/libyuv/+/3568424
Reviewed-by: Frank Barchard <fbarchard@chromium.org>
Commit-Queue: Frank Barchard <fbarchard@chromium.org>

1 files changed, 88 insertions, 0 deletions

diff --git a/unit_test/rotate_test.cc b/unit_test/rotate_test.cc
index c140960e..d3887414 100644
--- a/unit_test/rotate_test.cc
+++ b/unit_test/rotate_test.cc
@@ -137,6 +137,94 @@ TEST_F(LibYUVRotateTest, DISABLED_I420Rotate270_Odd) {
                  benchmark_cpu_info_);
 }
 
+static void I422TestRotate(int src_width,
+                           int src_height,
+                           int dst_width,
+                           int dst_height,
+                           libyuv::RotationMode mode,
+                           int benchmark_iterations,
+                           int disable_cpu_flags,
+                           int benchmark_cpu_info) {
+  if (src_width < 1) {
+    src_width = 1;
+  }
+  if (src_height == 0) {
+    src_height = 1;
+  }
+  if (dst_width < 1) {
+    dst_width = 1;
+  }
+  if (dst_height < 1) {
+    dst_height = 1;
+  }
+  int src_i422_y_size = src_width * Abs(src_height);
+  int src_i422_uv_size = ((src_width + 1) / 2) * Abs(src_height);
+  int src_i422_size = src_i422_y_size + src_i422_uv_size * 2;
+  align_buffer_page_end(src_i422, src_i422_size);
+  for (int i = 0; i < src_i422_size; ++i) {
+    src_i422[i] = fastrand() & 0xff;
+  }
+
+  int dst_i422_y_size = dst_width * dst_height;
+  int dst_i422_uv_size = ((dst_width + 1) / 2) * dst_height;
+  int dst_i422_size = dst_i422_y_size + dst_i422_uv_size * 2;
+  align_buffer_page_end(dst_i422_c, dst_i422_size);
+  align_buffer_page_end(dst_i422_opt, dst_i422_size);
+  memset(dst_i422_c, 2, dst_i422_size);
+  memset(dst_i422_opt, 3, dst_i422_size);
+
+  MaskCpuFlags(disable_cpu_flags);  // Disable all CPU optimization.
+  I422Rotate(src_i422, src_width, src_i422 + src_i422_y_size,
+             (src_width + 1) / 2, src_i422 + src_i422_y_size + src_i422_uv_size,
+             (src_width + 1) / 2, dst_i422_c, dst_width,
+             dst_i422_c + dst_i422_y_size, (dst_width + 1) / 2,
+             dst_i422_c + dst_i422_y_size + dst_i422_uv_size,
+             (dst_width + 1) / 2, src_width, src_height, mode);
+
+  MaskCpuFlags(benchmark_cpu_info);  // Enable all CPU optimization.
+  for (int i = 0; i < benchmark_iterations; ++i) {
+    I422Rotate(
+        src_i422, src_width, src_i422 + src_i422_y_size, (src_width + 1) / 2,
+        src_i422 + src_i422_y_size + src_i422_uv_size, (src_width + 1) / 2,
+        dst_i422_opt, dst_width, dst_i422_opt + dst_i422_y_size,
+        (dst_width + 1) / 2, dst_i422_opt + dst_i422_y_size + dst_i422_uv_size,
+        (dst_width + 1) / 2, src_width, src_height, mode);
+  }
+
+  // Rotation should be exact.
+  for (int i = 0; i < dst_i422_size; ++i) {
+    EXPECT_EQ(dst_i422_c[i], dst_i422_opt[i]);
+  }
+
+  free_aligned_buffer_page_end(dst_i422_c);
+  free_aligned_buffer_page_end(dst_i422_opt);
+  free_aligned_buffer_page_end(src_i422);
+}
+
+TEST_F(LibYUVRotateTest, I422Rotate0_Opt) {
+  I422TestRotate(benchmark_width_, benchmark_height_, benchmark_width_,
+                 benchmark_height_, kRotate0, benchmark_iterations_,
+                 disable_cpu_flags_, benchmark_cpu_info_);
+}
+
+TEST_F(LibYUVRotateTest, I422Rotate90_Opt) {
+  I422TestRotate(benchmark_width_, benchmark_height_, benchmark_height_,
+                 benchmark_width_, kRotate90, benchmark_iterations_,
+                 disable_cpu_flags_, benchmark_cpu_info_);
+}
+
+TEST_F(LibYUVRotateTest, I422Rotate180_Opt) {
+  I422TestRotate(benchmark_width_, benchmark_height_, benchmark_width_,
+                 benchmark_height_, kRotate180, benchmark_iterations_,
+                 disable_cpu_flags_, benchmark_cpu_info_);
+}
+
+TEST_F(LibYUVRotateTest, I422Rotate270_Opt) {
+  I422TestRotate(benchmark_width_, benchmark_height_, benchmark_height_,
+                 benchmark_width_, kRotate270, benchmark_iterations_,
+                 disable_cpu_flags_, benchmark_cpu_info_);
+}
+
 static void I444TestRotate(int src_width,
                            int src_height,
                            int dst_width,