Checking scale factors on access.

It is possible to have invalid scale factors and not access them
during decoding. Error is reported if we really try to use invalid scale
factors.

Change-Id: Ie532d3ea7325ee0c7a6ada08269f804350c80fdf

diff --git a/vp9/common/vp9_reconinter.c b/vp9/common/vp9_reconinter.c
index 1975e2e..89c2aa8 100644 (file)
--- a/vp9/common/vp9_reconinter.c
+++ b/vp9/common/vp9_reconinter.c
@@ -253,7 +253,7 @@ void vp9_setup_scale_factors(VP9_COMMON *cm, int i) {
     vp9_zero(*sf);
   } else {
     YV12_BUFFER_CONFIG *const fb = &cm->yv12_fb[ref];
-    vp9_setup_scale_factors_for_frame(cm, sf,
+    vp9_setup_scale_factors_for_frame(sf,
                                       fb->y_crop_width, fb->y_crop_height,
                                       cm->width, cm->height);
 

diff --git a/vp9/common/vp9_scale.c b/vp9/common/vp9_scale.c
index 12acac1..0b8dc23 100644 (file)
--- a/vp9/common/vp9_scale.c
+++ b/vp9/common/vp9_scale.c
@@ -10,7 +10,6 @@
 
 #include "./vp9_rtcd.h"
 #include "vp9/common/vp9_filter.h"
-#include "vp9/common/vp9_onyxc_int.h"
 #include "vp9/common/vp9_scale.h"
 
 static INLINE int scaled_x(int val, const struct scale_factors *scale) {
@@ -70,33 +69,32 @@ static int check_scale_factors(int other_w, int other_h,
          this_h <= 16 * other_h;
 }
 
-void vp9_setup_scale_factors_for_frame(struct VP9Common *cm,
-                                       struct scale_factors *scale,
+void vp9_setup_scale_factors_for_frame(struct scale_factors *scale,
                                        int other_w, int other_h,
                                        int this_w, int this_h) {
-  if (!check_scale_factors(other_w, other_h, this_w, this_h))
-    vpx_internal_error(&cm->error, VPX_CODEC_UNSUP_BITSTREAM,
-                       "Invalid scale factors");
-
+  if (!check_scale_factors(other_w, other_h, this_w, this_h)) {
+    scale->x_scale_fp = VP9_REF_INVALID_SCALE;
+    scale->y_scale_fp = VP9_REF_INVALID_SCALE;
+    return;
+  }
 
   scale->x_scale_fp = get_fixed_point_scale_factor(other_w, this_w);
-  scale->x_offset_q4 = 0;  // calculated per block
-  scale->x_step_q4 = scaled_x(16, scale);
-
   scale->y_scale_fp = get_fixed_point_scale_factor(other_h, this_h);
-  scale->y_offset_q4 = 0;  // calculated per block
+  scale->x_step_q4 = scaled_x(16, scale);
   scale->y_step_q4 = scaled_y(16, scale);
+  scale->x_offset_q4 = 0;  // calculated per block
+  scale->y_offset_q4 = 0;  // calculated per block
 
-  if (other_w == this_w && other_h == this_h) {
-    scale->scale_value_x = unscaled_value;
-    scale->scale_value_y = unscaled_value;
-    scale->set_scaled_offsets = set_offsets_without_scaling;
-    scale->scale_mv = unscaled_mv;
-  } else {
+  if (vp9_is_scaled(scale)) {
     scale->scale_value_x = scaled_x;
     scale->scale_value_y = scaled_y;
     scale->set_scaled_offsets = set_offsets_with_scaling;
     scale->scale_mv = scaled_mv;
+  } else {
+    scale->scale_value_x = unscaled_value;
+    scale->scale_value_y = unscaled_value;
+    scale->set_scaled_offsets = set_offsets_without_scaling;
+    scale->scale_mv = unscaled_mv;
   }
 
   // TODO(agrange): Investigate the best choice of functions to use here

diff --git a/vp9/common/vp9_scale.h b/vp9/common/vp9_scale.h
index e3fcae1..827ae9b 100644 (file)
--- a/vp9/common/vp9_scale.h
+++ b/vp9/common/vp9_scale.h
@@ -14,10 +14,9 @@
 #include "vp9/common/vp9_mv.h"
 #include "vp9/common/vp9_convolve.h"
 
-struct VP9Common;
-
 #define VP9_REF_SCALE_SHIFT 14
 #define VP9_REF_NO_SCALE (1 << VP9_REF_SCALE_SHIFT)
+#define VP9_REF_INVALID_SCALE -1
 
 struct scale_factors {
   int x_scale_fp;   // horizontal fixed point scale factor
@@ -35,11 +34,15 @@ struct scale_factors {
   convolve_fn_t predict[2][2][2];  // horiz, vert, avg
 };
 
-void vp9_setup_scale_factors_for_frame(struct VP9Common *cm,
-                                       struct scale_factors *scale,
+void vp9_setup_scale_factors_for_frame(struct scale_factors *scale,
                                        int other_w, int other_h,
                                        int this_w, int this_h);
 
+static int vp9_is_valid_scale(const struct scale_factors *sf) {
+  return sf->x_scale_fp != VP9_REF_INVALID_SCALE &&
+         sf->y_scale_fp != VP9_REF_INVALID_SCALE;
+}
+
 static int vp9_is_scaled(const struct scale_factors *sf) {
   return sf->x_scale_fp != VP9_REF_NO_SCALE ||
          sf->y_scale_fp != VP9_REF_NO_SCALE;

diff --git a/vp9/decoder/vp9_decodframe.c b/vp9/decoder/vp9_decodframe.c
index 70e85f9..58a01e4 100644 (file)
--- a/vp9/decoder/vp9_decodframe.c
+++ b/vp9/decoder/vp9_decodframe.c
@@ -202,11 +202,15 @@ static void set_ref(VP9D_COMP *pbi, int i, int mi_row, int mi_col) {
   VP9_COMMON *const cm = &pbi->common;
   MACROBLOCKD *const xd = &pbi->mb;
   MB_MODE_INFO *const mbmi = &xd->mode_info_context->mbmi;
-  const int ref = mbmi->ref_frame[i] - 1;
-
+  const int ref = mbmi->ref_frame[i] - LAST_FRAME;
   const YV12_BUFFER_CONFIG *cfg = &cm->yv12_fb[cm->active_ref_idx[ref]];
-  xd->scale_factor[i] = cm->active_ref_scale[ref];
-  setup_pre_planes(xd, i, cfg, mi_row, mi_col, &xd->scale_factor[i]);
+  const struct scale_factors *sf = &cm->active_ref_scale[ref];
+  if (!vp9_is_valid_scale(sf))
+    vpx_internal_error(&cm->error, VPX_CODEC_UNSUP_BITSTREAM,
+                       "Invalid scale factors");
+
+  xd->scale_factor[i] = *sf;
+  setup_pre_planes(xd, i, cfg, mi_row, mi_col, sf);
   xd->corrupted |= cfg->corrupted;
 }
 

diff --git a/vp9/encoder/vp9_temporal_filter.c b/vp9/encoder/vp9_temporal_filter.c
index 74fb07e..3052e8f 100644 (file)
--- a/vp9/encoder/vp9_temporal_filter.c
+++ b/vp9/encoder/vp9_temporal_filter.c
@@ -437,7 +437,7 @@ void vp9_temporal_filter_prepare(VP9_COMP *cpi, int distance) {
 #endif
 
   // Setup scaling factors. Scaling on each of the arnr frames is not supported
-  vp9_setup_scale_factors_for_frame(cm, &cpi->mb.e_mbd.scale_factor[0],
+  vp9_setup_scale_factors_for_frame(&cpi->mb.e_mbd.scale_factor[0],
       cm->yv12_fb[cm->new_fb_idx].y_crop_width,
       cm->yv12_fb[cm->new_fb_idx].y_crop_height,
       cm->width, cm->height);