libvpx: Pull from upstream

source/libvpx/vpx_scale/generic/yv12extend.c

 /*
  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 66 matching lines @@
                (ybf->y_crop_width + 1) / 2, (ybf->y_crop_height + 1) / 2,
                ybf->border / 2, ybf->border / 2,
                (ybf->border + ybf->y_height - ybf->y_crop_height + 1) / 2,
                (ybf->border + ybf->y_width - ybf->y_crop_width + 1) / 2);
 }
 
 #if CONFIG_VP9
 static void extend_frame(YV12_BUFFER_CONFIG *const ybf, int ext_size) {
   const int c_w = ybf->uv_crop_width;
   const int c_h = ybf->uv_crop_height;
-  const int c_ext_size = ext_size >> 1;
-  const int c_et = c_ext_size;
-  const int c_el = c_ext_size;
-  const int c_eb = c_ext_size + ybf->uv_height - ybf->uv_crop_height;
-  const int c_er = c_ext_size + ybf->uv_width - ybf->uv_crop_width;
+  const int ss_x = ybf->uv_width < ybf->y_width;
+  const int ss_y = ybf->uv_height < ybf->y_height;
+  const int c_et = ext_size >> ss_y;
+  const int c_el = ext_size >> ss_x;
+  const int c_eb = c_et + ybf->uv_height - ybf->uv_crop_height;
+  const int c_er = c_el + ybf->uv_width - ybf->uv_crop_width;
 
   assert(ybf->y_height - ybf->y_crop_height < 16);
   assert(ybf->y_width - ybf->y_crop_width < 16);
   assert(ybf->y_height - ybf->y_crop_height >= 0);
   assert(ybf->y_width - ybf->y_crop_width >= 0);
 
   extend_plane(ybf->y_buffer, ybf->y_stride,
                ybf->y_crop_width, ybf->y_crop_height,
                ext_size, ext_size,
                ext_size + ybf->y_height - ybf->y_crop_height,
@@ skipping 66 matching lines @@
   int row;
   const uint8_t *src = src_ybc->y_buffer;
   uint8_t *dst = dst_ybc->y_buffer;
 
   for (row = 0; row < src_ybc->y_height; ++row) {
     vpx_memcpy(dst, src, src_ybc->y_width);
     src += src_ybc->y_stride;
     dst += dst_ybc->y_stride;
   }
 }