Upscale frame correctly in foreach_rtile_in_tile

The restoration tiles (rtiles) divide the upscaled frame, not the
encoded one.

Change-Id: I2d08fe926d694fee7064461685289d3fd1c1de0c

av1/common/resize.c

@@ -1178,6 +1178,17 @@ void av1_calculate_scaled_size(int *width, int *height, int num) {
   }
 }
 
+// Inverse of av1_calculate_scaled_size() above: calculates the original size
+// from the given scaled dimensions and the scale numerator.
+void av1_calculate_unscaled_size(int *width, int *height, int num) {
+  if (num != SCALE_DENOMINATOR) {
+    // Note: av1_calculate_scaled_size() rounds *up* after division when the
+    // resulting dimensions are odd. So here, we round *down*.
+    *width = *width * SCALE_DENOMINATOR / num;
+    *height = *height * SCALE_DENOMINATOR / num;
+  }
+}
+
 #if CONFIG_FRAME_SUPERRES
 // TODO(afergs): Look for in-place upscaling
 // TODO(afergs): aom_ vs av1_ functions? Which can I use?

av1/common/resize.h

@@ -85,8 +85,14 @@ YV12_BUFFER_CONFIG *av1_scale_if_required(AV1_COMMON *cm,
                                           YV12_BUFFER_CONFIG *unscaled,
                                           YV12_BUFFER_CONFIG *scaled);
 
+// Calculates the scaled size from the given original dimensions and the scale
+// numerator.
 void av1_calculate_scaled_size(int *width, int *height, int num);
 
+// Inverse of av1_calculate_scaled_size() above: calculates the original size
+// from the given scaled dimensions and the scale numerator.
+void av1_calculate_unscaled_size(int *width, int *height, int num);
+
 #if CONFIG_FRAME_SUPERRES
 void av1_superres_upscale(AV1_COMMON *cm, BufferPool *const pool);
 

av1/encoder/pickrst.c

@@ -540,6 +540,21 @@ static void foreach_rtile_in_tile(const struct rest_search_ctxt *ctxt,
     tile_row_end = ROUND_POWER_OF_TWO(tile_row_end, cm->subsampling_y);
   }
 
+#if CONFIG_FRAME_SUPERRES
+  // If upscaling is enabled, the tile limits need scaling to match the
+  // upscaled frame where the restoration tiles live. To do this, scale up the
+  // top-left and bottom-right of the tile.
+  if (!av1_superres_unscaled(cm)) {
+    av1_calculate_unscaled_size(&tile_col_start, &tile_row_start,
+                                cm->superres_scale_numerator);
+    av1_calculate_unscaled_size(&tile_col_end, &tile_row_end,
+                                cm->superres_scale_numerator);
+    // Make sure we don't fall off the bottom-right of the frame.
+    tile_col_end = AOMMIN(tile_col_end, ctxt->plane_width);
+    tile_row_end = AOMMIN(tile_row_end, ctxt->plane_height);
+  }
+#endif  // CONFIG_FRAME_SUPERRES
+
   const int rtile_size = rsi->restoration_tilesize;
   const int rtile_col0 = (tile_col_start + rtile_size - 1) / rtile_size;
   const int rtile_col1 =