Allow flow estimation on mismatched frame strides

Now that aom_compute_flow_at_point uses the strides corresponding to the
src and ref buffers, we can remove the requirement that the src and ref
buffers have the same stride in
av1_compute_global_motion_feature_match(),
av1_compute_global_motion_disflow(), and
update_valid_ref_frames_for_gm().

Delete the DisflowTest.MismatchedStrides test because mismatched strides
are no longer an error condition for av1_compute_global_motion_disflow()
and av1_compute_global_motion_feature_match().

Change-Id: I8ec4fcd7c88d618b7b411e49622f8155d664ad95

aom_dsp/flow_estimation/corner_match.c

diff --git a/aom_dsp/flow_estimation/corner_match.c b/aom_dsp/flow_estimation/corner_match.c
index 72b65b3..3679736 100644
--- a/aom_dsp/flow_estimation/corner_match.c
+++ b/aom_dsp/flow_estimation/corner_match.c
@@ -289,8 +289,7 @@
   assert(ref_pyramid->layers[0].height == src_height);
   const int ref_stride = ref_pyramid->layers[0].stride;
 
-  if (ref_stride != src_stride || src_corners->num_corners == 0 ||
-      ref_corners->num_corners == 0) {
+  if (src_corners->num_corners == 0 || ref_corners->num_corners == 0) {
     return false;
   }
 

aom_dsp/flow_estimation/disflow.c

diff --git a/aom_dsp/flow_estimation/disflow.c b/aom_dsp/flow_estimation/disflow.c
index 22d1d44..a275673 100644
--- a/aom_dsp/flow_estimation/disflow.c
+++ b/aom_dsp/flow_estimation/disflow.c
@@ -812,9 +812,6 @@
     return false;
   }
 
-  if (ref_pyramid->layers[0].stride != src_pyramid->layers[0].stride) {
-    return false;
-  }
   if (src_width < (1 << DOWNSAMPLE_SHIFT) ||
       src_height < (1 << DOWNSAMPLE_SHIFT)) {
     return false;

av1/encoder/global_motion_facade.c

diff --git a/av1/encoder/global_motion_facade.c b/av1/encoder/global_motion_facade.c
index 7b1af9c..4fdad0b 100644
--- a/av1/encoder/global_motion_facade.c
+++ b/av1/encoder/global_motion_facade.c
@@ -314,7 +314,6 @@
 
     if (ref_buf[frame]->y_crop_width == cpi->source->y_crop_width &&
         ref_buf[frame]->y_crop_height == cpi->source->y_crop_height &&
-        ref_buf[frame]->y_stride == cpi->source->y_stride &&
         do_gm_search_logic(&cpi->sf, frame) && !prune_ref_frames &&
         ref_pyr_lvl <= pyr_lvl && !cur_frame_gm_disabled) {
       assert(ref_buf[frame] != NULL);

test/disflow_test.cc

diff --git a/test/disflow_test.cc b/test/disflow_test.cc
index 78f9565..f852608 100644
--- a/test/disflow_test.cc
+++ b/test/disflow_test.cc
@@ -179,36 +179,6 @@
   aom_free_frame_buffer(&src);
   aom_free_frame_buffer(&ref);
 }
-
-TEST(DisflowTest, MismatchedStrides) {
-  YV12_BUFFER_CONFIG src = {};
-  YV12_BUFFER_CONFIG ref = {};
-
-  constexpr int kWidth = 165;
-  constexpr int kHeight = 513;
-  ASSERT_EQ(aom_alloc_frame_buffer(&src, kWidth, kHeight, 1, 1, 0,
-                                   AOM_BORDER_IN_PIXELS, 0, true, 0),
-            0);
-  ASSERT_EQ(
-      aom_alloc_frame_buffer(&ref, kWidth, kHeight, 1, 1, 0, 96, 0, true, 0),
-      0);
-  EXPECT_NE(src.y_stride, ref.y_stride);
-
-  MotionModel motion_models[1];
-  bool mem_alloc_failed = false;
-  bool ret = av1_compute_global_motion_disflow(
-      TRANSLATION, &src, &ref, 8, 0, motion_models, 1, &mem_alloc_failed);
-  EXPECT_FALSE(ret);
-  EXPECT_FALSE(mem_alloc_failed);
-
-  ret = av1_compute_global_motion_feature_match(
-      TRANSLATION, &src, &ref, 8, 0, motion_models, 1, &mem_alloc_failed);
-  EXPECT_FALSE(ret);
-  EXPECT_FALSE(mem_alloc_failed);
-
-  aom_free_frame_buffer(&src);
-  aom_free_frame_buffer(&ref);
-}
 #endif  // CONFIG_AV1_ENCODER && !CONFIG_REALTIME_ONLY
 
 }  // namespace