Parse VP9 compressed header

media/filters/vp9_uncompressed_header_parser.cc

Index: media/filters/vp9_uncompressed_header_parser.cc
diff --git a/media/filters/vp9_uncompressed_header_parser.cc b/media/filters/vp9_uncompressed_header_parser.cc
new file mode 100644
index 0000000000000000000000000000000000000000..7ec6e2f277c2fddb86fea6f67eeb83f3d870c9a9
--- /dev/null
+++ b/media/filters/vp9_uncompressed_header_parser.cc
@@ -0,0 +1,1084 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "media/filters/vp9_uncompressed_header_parser.h"
+
+#include "base/logging.h"
+
+namespace media {
+
+namespace {
+
+// 10.5 Default probability tables
+Vp9FrameContext kVp9DefaultFrameContext = {
+    .tx_probs_8x8 = {{100}, {66}},
+    .tx_probs_16x16 = {{20, 152}, {15, 101}},
+    .tx_probs_32x32 = {{3, 136, 37}, {5, 52, 13}},
+    .coef_probs =
+        {// 4x4
+         {{{{{195, 29, 183}, {84, 49, 136}, {8, 42, 71}},
+            {{31, 107, 169},
+             {35, 99, 159},
+             {17, 82, 140},
+             {8, 66, 114},
+             {2, 44, 76},
+             {1, 19, 32}},
+            {{40, 132, 201},
+             {29, 114, 187},
+             {13, 91, 157},
+             {7, 75, 127},
+             {3, 58, 95},
+             {1, 28, 47}},
+            {{69, 142, 221},
+             {42, 122, 201},
+             {15, 91, 159},
+             {6, 67, 121},
+             {1, 42, 77},
+             {1, 17, 31}},
+            {{102, 148, 228},
+             {67, 117, 204},
+             {17, 82, 154},
+             {6, 59, 114},
+             {2, 39, 75},
+             {1, 15, 29}},
+            {{156, 57, 233},
+             {119, 57, 212},
+             {58, 48, 163},
+             {29, 40, 124},
+             {12, 30, 81},
+             {3, 12, 31}}},
+           {{{191, 107, 226}, {124, 117, 204}, {25, 99, 155}},
+            {{29, 148, 210},
+             {37, 126, 194},
+             {8, 93, 157},
+             {2, 68, 118},
+             {1, 39, 69},
+             {1, 17, 33}},
+            {{41, 151, 213},
+             {27, 123, 193},
+             {3, 82, 144},
+             {1, 58, 105},
+             {1, 32, 60},
+             {1, 13, 26}},
+            {{59, 159, 220},
+             {23, 126, 198},
+             {4, 88, 151},
+             {1, 66, 114},
+             {1, 38, 71},
+             {1, 18, 34}},
+            {{114, 136, 232},
+             {51, 114, 207},
+             {11, 83, 155},
+             {3, 56, 105},
+             {1, 33, 65},
+             {1, 17, 34}},
+            {{149, 65, 234},
+             {121, 57, 215},
+             {61, 49, 166},
+             {28, 36, 114},
+             {12, 25, 76},
+             {3, 16, 42}}}},
+          {{{{214, 49, 220}, {132, 63, 188}, {42, 65, 137}},
+            {{85, 137, 221},
+             {104, 131, 216},
+             {49, 111, 192},
+             {21, 87, 155},
+             {2, 49, 87},
+             {1, 16, 28}},
+            {{89, 163, 230},
+             {90, 137, 220},
+             {29, 100, 183},
+             {10, 70, 135},
+             {2, 42, 81},
+             {1, 17, 33}},
+            {{108, 167, 237},
+             {55, 133, 222},
+             {15, 97, 179},
+             {4, 72, 135},
+             {1, 45, 85},
+             {1, 19, 38}},
+            {{124, 146, 240},
+             {66, 124, 224},
+             {17, 88, 175},
+             {4, 58, 122},
+             {1, 36, 75},
+             {1, 18, 37}},
+            {{141, 79, 241},
+             {126, 70, 227},
+             {66, 58, 182},
+             {30, 44, 136},
+             {12, 34, 96},
+             {2, 20, 47}}},
+           {{{229, 99, 249}, {143, 111, 235}, {46, 109, 192}},
+            {{82, 158, 236},
+             {94, 146, 224},
+             {25, 117, 191},
+             {9, 87, 149},
+             {3, 56, 99},
+             {1, 33, 57}},
+            {{83, 167, 237},
+             {68, 145, 222},
+             {10, 103, 177},
+             {2, 72, 131},
+             {1, 41, 79},
+             {1, 20, 39}},
+            {{99, 167, 239},
+             {47, 141, 224},
+             {10, 104, 178},
+             {2, 73, 133},
+             {1, 44, 85},
+             {1, 22, 47}},
+            {{127, 145, 243},
+             {71, 129, 228},
+             {17, 93, 177},
+             {3, 61, 124},
+             {1, 41, 84},
+             {1, 21, 52}},
+            {{157, 78, 244},
+             {140, 72, 231},
+             {69, 58, 184},
+             {31, 44, 137},
+             {14, 38, 105},
+             {8, 23, 61}}}}},
+         // 8x8
+         {{{{{125, 34, 187}, {52, 41, 133}, {6, 31, 56}},
+            {{37, 109, 153},
+             {51, 102, 147},
+             {23, 87, 128},
+             {8, 67, 101},
+             {1, 41, 63},
+             {1, 19, 29}},
+            {{31, 154, 185},
+             {17, 127, 175},
+             {6, 96, 145},
+             {2, 73, 114},
+             {1, 51, 82},
+             {1, 28, 45}},
+            {{23, 163, 200},
+             {10, 131, 185},
+             {2, 93, 148},
+             {1, 67, 111},
+             {1, 41, 69},
+             {1, 14, 24}},
+            {{29, 176, 217},
+             {12, 145, 201},
+             {3, 101, 156},
+             {1, 69, 111},
+             {1, 39, 63},
+             {1, 14, 23}},
+            {{57, 192, 233},
+             {25, 154, 215},
+             {6, 109, 167},
+             {3, 78, 118},
+             {1, 48, 69},
+             {1, 21, 29}}},
+           {{{202, 105, 245}, {108, 106, 216}, {18, 90, 144}},
+            {{33, 172, 219},
+             {64, 149, 206},
+             {14, 117, 177},
+             {5, 90, 141},
+             {2, 61, 95},
+             {1, 37, 57}},
+            {{33, 179, 220},
+             {11, 140, 198},
+             {1, 89, 148},
+             {1, 60, 104},
+             {1, 33, 57},
+             {1, 12, 21}},
+            {{30, 181, 221},
+             {8, 141, 198},
+             {1, 87, 145},
+             {1, 58, 100},
+             {1, 31, 55},
+             {1, 12, 20}},
+            {{32, 186, 224},
+             {7, 142, 198},
+             {1, 86, 143},
+             {1, 58, 100},
+             {1, 31, 55},
+             {1, 12, 22}},
+            {{57, 192, 227},
+             {20, 143, 204},
+             {3, 96, 154},
+             {1, 68, 112},
+             {1, 42, 69},
+             {1, 19, 32}}}},
+          {{{{212, 35, 215}, {113, 47, 169}, {29, 48, 105}},
+            {{74, 129, 203},
+             {106, 120, 203},
+             {49, 107, 178},
+             {19, 84, 144},
+             {4, 50, 84},
+             {1, 15, 25}},
+            {{71, 172, 217},
+             {44, 141, 209},
+             {15, 102, 173},
+             {6, 76, 133},
+             {2, 51, 89},
+             {1, 24, 42}},
+            {{64, 185, 231},
+             {31, 148, 216},
+             {8, 103, 175},
+             {3, 74, 131},
+             {1, 46, 81},
+             {1, 18, 30}},
+            {{65, 196, 235},
+             {25, 157, 221},
+             {5, 105, 174},
+             {1, 67, 120},
+             {1, 38, 69},
+             {1, 15, 30}},
+            {{65, 204, 238},
+             {30, 156, 224},
+             {7, 107, 177},
+             {2, 70, 124},
+             {1, 42, 73},
+             {1, 18, 34}}},
+           {{{225, 86, 251}, {144, 104, 235}, {42, 99, 181}},
+            {{85, 175, 239},
+             {112, 165, 229},
+             {29, 136, 200},
+             {12, 103, 162},
+             {6, 77, 123},
+             {2, 53, 84}},
+            {{75, 183, 239},
+             {30, 155, 221},
+             {3, 106, 171},
+             {1, 74, 128},
+             {1, 44, 76},
+             {1, 17, 28}},
+            {{73, 185, 240},
+             {27, 159, 222},
+             {2, 107, 172},
+             {1, 75, 127},
+             {1, 42, 73},
+             {1, 17, 29}},
+            {{62, 190, 238},
+             {21, 159, 222},
+             {2, 107, 172},
+             {1, 72, 122},
+             {1, 40, 71},
+             {1, 18, 32}},
+            {{61, 199, 240},
+             {27, 161, 226},
+             {4, 113, 180},
+             {1, 76, 129},
+             {1, 46, 80},
+             {1, 23, 41}}}}},
+         // 16x16
+         {{{{{7, 27, 153}, {5, 30, 95}, {1, 16, 30}},
+            {{50, 75, 127},
+             {57, 75, 124},
+             {27, 67, 108},
+             {10, 54, 86},
+             {1, 33, 52},
+             {1, 12, 18}},
+            {{43, 125, 151},
+             {26, 108, 148},
+             {7, 83, 122},
+             {2, 59, 89},
+             {1, 38, 60},
+             {1, 17, 27}},
+            {{23, 144, 163},
+             {13, 112, 154},
+             {2, 75, 117},
+             {1, 50, 81},
+             {1, 31, 51},
+             {1, 14, 23}},
+            {{18, 162, 185},
+             {6, 123, 171},
+             {1, 78, 125},
+             {1, 51, 86},
+             {1, 31, 54},
+             {1, 14, 23}},
+            {{15, 199, 227},
+             {3, 150, 204},
+             {1, 91, 146},
+             {1, 55, 95},
+             {1, 30, 53},
+             {1, 11, 20}}},
+           {{{19, 55, 240}, {19, 59, 196}, {3, 52, 105}},
+            {{41, 166, 207},
+             {104, 153, 199},
+             {31, 123, 181},
+             {14, 101, 152},
+             {5, 72, 106},
+             {1, 36, 52}},
+            {{35, 176, 211},
+             {12, 131, 190},
+             {2, 88, 144},
+             {1, 60, 101},
+             {1, 36, 60},
+             {1, 16, 28}},
+            {{28, 183, 213},
+             {8, 134, 191},
+             {1, 86, 142},
+             {1, 56, 96},
+             {1, 30, 53},
+             {1, 12, 20}},
+            {{20, 190, 215},
+             {4, 135, 192},
+             {1, 84, 139},
+             {1, 53, 91},
+             {1, 28, 49},
+             {1, 11, 20}},
+            {{13, 196, 216},
+             {2, 137, 192},
+             {1, 86, 143},
+             {1, 57, 99},
+             {1, 32, 56},
+             {1, 13, 24}}}},
+          {{{{211, 29, 217}, {96, 47, 156}, {22, 43, 87}},
+            {{78, 120, 193},
+             {111, 116, 186},
+             {46, 102, 164},
+             {15, 80, 128},
+             {2, 49, 76},
+             {1, 18, 28}},
+            {{71, 161, 203},
+             {42, 132, 192},
+             {10, 98, 150},
+             {3, 69, 109},
+             {1, 44, 70},
+             {1, 18, 29}},
+            {{57, 186, 211},
+             {30, 140, 196},
+             {4, 93, 146},
+             {1, 62, 102},
+             {1, 38, 65},
+             {1, 16, 27}},
+            {{47, 199, 217},
+             {14, 145, 196},
+             {1, 88, 142},
+             {1, 57, 98},
+             {1, 36, 62},
+             {1, 15, 26}},
+            {{26, 219, 229},
+             {5, 155, 207},
+             {1, 94, 151},
+             {1, 60, 104},
+             {1, 36, 62},
+             {1, 16, 28}}},
+           {{{233, 29, 248}, {146, 47, 220}, {43, 52, 140}},
+            {{100, 163, 232},
+             {179, 161, 222},
+             {63, 142, 204},
+             {37, 113, 174},
+             {26, 89, 137},
+             {18, 68, 97}},
+            {{85, 181, 230},
+             {32, 146, 209},
+             {7, 100, 164},
+             {3, 71, 121},
+             {1, 45, 77},
+             {1, 18, 30}},
+            {{65, 187, 230},
+             {20, 148, 207},
+             {2, 97, 159},
+             {1, 68, 116},
+             {1, 40, 70},
+             {1, 14, 29}},
+            {{40, 194, 227},
+             {8, 147, 204},
+             {1, 94, 155},
+             {1, 65, 112},
+             {1, 39, 66},
+             {1, 14, 26}},
+            {{16, 208, 228},
+             {3, 151, 207},
+             {1, 98, 160},
+             {1, 67, 117},
+             {1, 41, 74},
+             {1, 17, 31}}}}},
+         // 32x32
+         {{{{{17, 38, 140}, {7, 34, 80}, {1, 17, 29}},
+            {{37, 75, 128},
+             {41, 76, 128},
+             {26, 66, 116},
+             {12, 52, 94},
+             {2, 32, 55},
+             {1, 10, 16}},
+            {{50, 127, 154},
+             {37, 109, 152},
+             {16, 82, 121},
+             {5, 59, 85},
+             {1, 35, 54},
+             {1, 13, 20}},
+            {{40, 142, 167},
+             {17, 110, 157},
+             {2, 71, 112},
+             {1, 44, 72},
+             {1, 27, 45},
+             {1, 11, 17}},
+            {{30, 175, 188},
+             {9, 124, 169},
+             {1, 74, 116},
+             {1, 48, 78},
+             {1, 30, 49},
+             {1, 11, 18}},
+            {{10, 222, 223},
+             {2, 150, 194},
+             {1, 83, 128},
+             {1, 48, 79},
+             {1, 27, 45},
+             {1, 11, 17}}},
+           {{{36, 41, 235}, {29, 36, 193}, {10, 27, 111}},
+            {{85, 165, 222},
+             {177, 162, 215},
+             {110, 135, 195},
+             {57, 113, 168},
+             {23, 83, 120},
+             {10, 49, 61}},
+            {{85, 190, 223},
+             {36, 139, 200},
+             {5, 90, 146},
+             {1, 60, 103},
+             {1, 38, 65},
+             {1, 18, 30}},
+            {{72, 202, 223},
+             {23, 141, 199},
+             {2, 86, 140},
+             {1, 56, 97},
+             {1, 36, 61},
+             {1, 16, 27}},
+            {{55, 218, 225},
+             {13, 145, 200},
+             {1, 86, 141},
+             {1, 57, 99},
+             {1, 35, 61},
+             {1, 13, 22}},
+            {{15, 235, 212},
+             {1, 132, 184},
+             {1, 84, 139},
+             {1, 57, 97},
+             {1, 34, 56},
+             {1, 14, 23}}}},
+          {{{{181, 21, 201}, {61, 37, 123}, {10, 38, 71}},
+            {{47, 106, 172},
+             {95, 104, 173},
+             {42, 93, 159},
+             {18, 77, 131},
+             {4, 50, 81},
+             {1, 17, 23}},
+            {{62, 147, 199},
+             {44, 130, 189},
+             {28, 102, 154},
+             {18, 75, 115},
+             {2, 44, 65},
+             {1, 12, 19}},
+            {{55, 153, 210},
+             {24, 130, 194},
+             {3, 93, 146},
+             {1, 61, 97},
+             {1, 31, 50},
+             {1, 10, 16}},
+            {{49, 186, 223},
+             {17, 148, 204},
+             {1, 96, 142},
+             {1, 53, 83},
+             {1, 26, 44},
+             {1, 11, 17}},
+            {{13, 217, 212},
+             {2, 136, 180},
+             {1, 78, 124},
+             {1, 50, 83},
+             {1, 29, 49},
+             {1, 14, 23}}},
+           {{{197, 13, 247}, {82, 17, 222}, {25, 17, 162}},
+            {{126, 186, 247},
+             {234, 191, 243},
+             {176, 177, 234},
+             {104, 158, 220},
+             {66, 128, 186},
+             {55, 90, 137}},
+            {{111, 197, 242},
+             {46, 158, 219},
+             {9, 104, 171},
+             {2, 65, 125},
+             {1, 44, 80},
+             {1, 17, 91}},
+            {{104, 208, 245},
+             {39, 168, 224},
+             {3, 109, 162},
+             {1, 79, 124},
+             {1, 50, 102},
+             {1, 43, 102}},
+            {{84, 220, 246},
+             {31, 177, 231},
+             {2, 115, 180},
+             {1, 79, 134},
+             {1, 55, 77},
+             {1, 60, 79}},
+            {{43, 243, 240},
+             {8, 180, 217},
+             {1, 115, 166},
+             {1, 84, 121},
+             {1, 51, 67},
+             {1, 16, 6}}}}}},
+    .skip_prob = {192, 128, 64},
+    .inter_mode_probs = {{2, 173, 34},
+                         {7, 145, 85},
+                         {7, 166, 63},
+                         {7, 94, 66},
+                         {8, 64, 46},
+                         {17, 81, 31},
+                         {25, 29, 30}},
+    .interp_filter_probs = {{235, 162}, {36, 255}, {34, 3}, {149, 144}},
+    .is_inter_prob = {9, 102, 187, 225},
+    .comp_mode_prob = {239, 183, 119, 96, 41},
+    .single_ref_prob = {{33, 16}, {77, 74}, {142, 142}, {172, 170}, {238, 247}},
+    .comp_ref_prob = {50, 126, 123, 221, 226},
+    .y_mode_probs = {{65, 32, 18, 144, 162, 194, 41, 51, 98},
+                     {132, 68, 18, 165, 217, 196, 45, 40, 78},
+                     {173, 80, 19, 176, 240, 193, 64, 35, 46},
+                     {221, 135, 38, 194, 248, 121, 96, 85, 29}},
+    .uv_mode_probs = {{120, 7, 76, 176, 208, 126, 28, 54, 103},
+                      {48, 12, 154, 155, 139, 90, 34, 117, 119},
+                      {67, 6, 25, 204, 243, 158, 13, 21, 96},
+                      {97, 5, 44, 131, 176, 139, 48, 68, 97},
+                      {83, 5, 42, 156, 111, 152, 26, 49, 152},
+                      {80, 5, 58, 178, 74, 83, 33, 62, 145},
+                      {86, 5, 32, 154, 192, 168, 14, 22, 163},
+                      {85, 5, 32, 156, 216, 148, 19, 29, 73},
+                      {77, 7, 64, 116, 132, 122, 37, 126, 120},
+                      {101, 21, 107, 181, 192, 103, 19, 67, 125}},
+    .partition_probs = {{199, 122, 141},
+                        {147, 63, 159},
+                        {148, 133, 118},
+                        {121, 104, 114},
+                        {174, 73, 87},
+                        {92, 41, 83},
+                        {82, 99, 50},
+                        {53, 39, 39},
+                        {177, 58, 59},
+                        {68, 26, 63},
+                        {52, 79, 25},
+                        {17, 14, 12},
+                        {222, 34, 30},
+                        {72, 16, 44},
+                        {58, 32, 12},
+                        {10, 7, 6}},
+    .mv_joint_probs = {32, 64, 96},
+    .mv_sign_prob = {128, 128},
+    .mv_class_probs = {{224, 144, 192, 168, 192, 176, 192, 198, 198, 245},
+                       {216, 128, 176, 160, 176, 176, 192, 198, 198, 208}},
+    .mv_class0_bit_prob = {216, 208},
+    .mv_bits_prob = {{136, 140, 148, 160, 176, 192, 224, 234, 234, 240},
+                     {136, 140, 148, 160, 176, 192, 224, 234, 234, 240}},
+    .mv_class0_fr_probs = {{{128, 128, 64}, {96, 112, 64}},
+                           {{128, 128, 64}, {96, 112, 64}}},
+    .mv_fr_probs = {{64, 96, 64}, {64, 96, 64}},
+    .mv_class0_hp_prob = {160, 160},
+    .mv_hp_prob = {128, 128},
+};
+
+// Helper function for Vp9Parser::ReadTileInfo. Defined as
+// calc_min_log2_tile_cols in spec 6.2.14 Tile size calculation.
+int GetMinLog2TileCols(int sb64_cols) {
+  const int kMaxTileWidthB64 = 64;
+  int min_log2 = 0;
+  while ((kMaxTileWidthB64 << min_log2) < sb64_cols)
+    min_log2++;
+  return min_log2;
+}
+
+// Helper function for Vp9Parser::ReadTileInfo. Defined as
+// calc_max_log2_tile_cols in spec 6.2.14 Tile size calculation.
+int GetMaxLog2TileCols(int sb64_cols) {
+  const int kMinTileWidthB64 = 4;
+  int max_log2 = 1;
+  while ((sb64_cols >> max_log2) >= kMinTileWidthB64)
+    max_log2++;
+  return max_log2 - 1;
+}
+
+}  // namespace
+
+Vp9UncompressedHeaderParser::Vp9UncompressedHeaderParser(
+    Vp9Parser::Context* context)
+    : context_(context) {}
+
+uint8_t Vp9UncompressedHeaderParser::ReadProfile() {
+  uint8_t profile = 0;
+
+  // LSB first.
+  if (reader_.ReadBool())
+    profile |= 1;
+  if (reader_.ReadBool())
+    profile |= 2;
+  if (profile > 2 && reader_.ReadBool())
+    profile += 1;
+  return profile;
+}
+
+// 6.2.1 Frame sync syntax
+bool Vp9UncompressedHeaderParser::VerifySyncCode() {
+  const int kSyncCode = 0x498342;
+  if (reader_.ReadLiteral(8 * 3) != kSyncCode) {
+    DVLOG(1) << "Invalid frame sync code";
+    return false;
+  }
+  return true;
+}
+
+// 6.2.2 Color config syntax
+bool Vp9UncompressedHeaderParser::ReadColorConfig(Vp9FrameHeader* fhdr) {
+  if (fhdr->profile == 2 || fhdr->profile == 3) {
+    fhdr->bit_depth = reader_.ReadBool() ? 12 : 10;
+  } else {
+    fhdr->bit_depth = 8;
+  }
+
+  fhdr->color_space = static_cast<Vp9ColorSpace>(reader_.ReadLiteral(3));
+  if (fhdr->color_space != Vp9ColorSpace::SRGB) {
+    fhdr->color_range = reader_.ReadBool();
+    if (fhdr->profile == 1 || fhdr->profile == 3) {
+      fhdr->subsampling_x = reader_.ReadBool() ? 1 : 0;
+      fhdr->subsampling_y = reader_.ReadBool() ? 1 : 0;
+      if (fhdr->subsampling_x == 1 && fhdr->subsampling_y == 1) {
+        DVLOG(1) << "4:2:0 color not supported in profile 1 or 3";
+        return false;
+      }
+      bool reserved = reader_.ReadBool();
+      if (reserved) {
+        DVLOG(1) << "reserved bit set";
+        return false;
+      }
+    } else {
+      fhdr->subsampling_x = fhdr->subsampling_y = 1;
+    }
+  } else {
+    fhdr->color_range = true;
+    if (fhdr->profile == 1 || fhdr->profile == 3) {
+      fhdr->subsampling_x = fhdr->subsampling_y = 0;
+
+      bool reserved = reader_.ReadBool();
+      if (reserved) {
+        DVLOG(1) << "reserved bit set";
+        return false;
+      }
+    } else {
+      DVLOG(1) << "4:4:4 color not supported in profile 0 or 2";
+      return false;
+    }
+  }
+
+  return true;
+}
+
+// 6.2.3 Frame size syntax
+void Vp9UncompressedHeaderParser::ReadFrameSize(Vp9FrameHeader* fhdr) {
+  fhdr->frame_width = reader_.ReadLiteral(16) + 1;
+  fhdr->frame_height = reader_.ReadLiteral(16) + 1;
+}
+
+// 6.2.4 Render size syntax
+void Vp9UncompressedHeaderParser::ReadRenderSize(Vp9FrameHeader* fhdr) {
+  if (reader_.ReadBool()) {
+    fhdr->render_width = reader_.ReadLiteral(16) + 1;
+    fhdr->render_height = reader_.ReadLiteral(16) + 1;
+  } else {
+    fhdr->render_width = fhdr->frame_width;
+    fhdr->render_height = fhdr->frame_height;
+  }
+}
+
+// 6.2.5 Frame size with refs syntax
+bool Vp9UncompressedHeaderParser::ReadFrameSizeFromRefs(Vp9FrameHeader* fhdr) {
+  bool found_ref = false;
+  for (const auto& idx : fhdr->ref_frame_idx) {
+    found_ref = reader_.ReadBool();
+    if (found_ref) {
+      const Vp9Parser::ReferenceSlot& ref = context_->ref_slots[idx];
+      DCHECK(ref.initialized);
+      fhdr->frame_width = ref.frame_width;
+      fhdr->frame_height = ref.frame_height;
+
+      const unsigned kMaxDimension = 1u << 16;
+      DCHECK_LE(fhdr->frame_width, kMaxDimension);
+      DCHECK_LE(fhdr->frame_height, kMaxDimension);
+      break;
+    }
+  }
+
+  if (!found_ref)
+    ReadFrameSize(fhdr);
+
+  // 7.2.5 Frame size with refs semantics
+  bool has_valid_ref_frame = false;
+  for (const auto& idx : fhdr->ref_frame_idx) {
+    const Vp9Parser::ReferenceSlot& ref = context_->ref_slots[idx];
+    if (2 * fhdr->frame_width >= ref.frame_width &&
+        2 * fhdr->frame_height >= ref.frame_height &&
+        fhdr->frame_width <= 16 * ref.frame_width &&
+        fhdr->frame_height <= 16 * ref.frame_height) {
+      has_valid_ref_frame = true;
+      break;
+    }
+  }
+  if (!has_valid_ref_frame) {
+    DVLOG(1) << "There should be at least one reference frame meeting "
+             << "size conditions.";
+    return false;
+  }
+
+  ReadRenderSize(fhdr);
+  return true;
+}
+
+// 6.2.7 Interpolation filter syntax
+Vp9InterpolationFilter Vp9UncompressedHeaderParser::ReadInterpolationFilter() {
+  if (reader_.ReadBool())
+    return Vp9InterpolationFilter::SWITCHABLE;
+
+  // The mapping table for next two bits.
+  const Vp9InterpolationFilter table[] = {
+      Vp9InterpolationFilter::EIGHTTAP_SMOOTH, Vp9InterpolationFilter::EIGHTTAP,
+      Vp9InterpolationFilter::EIGHTTAP_SHARP, Vp9InterpolationFilter::BILINEAR,
+  };
+  return table[reader_.ReadLiteral(2)];
+}
+
+void Vp9UncompressedHeaderParser::SetupPastIndependence(Vp9FrameHeader* fhdr) {
+  memset(&context_->segmentation, 0, sizeof(context_->segmentation));
+  ResetLoopfilter();
+  fhdr->frame_context = kVp9DefaultFrameContext;
+  DCHECK(Vp9FrameContextManager::IsValidFrameContext(fhdr->frame_context));
+}
+
+// 6.2.8 Loop filter params syntax
+void Vp9UncompressedHeaderParser::ReadLoopFilterParams() {
+  Vp9LoopFilterParams& loop_filter = context_->loop_filter;
+
+  loop_filter.level = reader_.ReadLiteral(6);
+  loop_filter.sharpness = reader_.ReadLiteral(3);
+  loop_filter.delta_update = false;
+
+  loop_filter.delta_enabled = reader_.ReadBool();
+  if (loop_filter.delta_enabled) {
+    loop_filter.delta_update = reader_.ReadBool();
+    if (loop_filter.delta_update) {
+      for (size_t i = 0; i < Vp9FrameType::VP9_FRAME_MAX; i++) {
+        loop_filter.update_ref_deltas[i] = reader_.ReadBool();
+        if (loop_filter.update_ref_deltas[i])
+          loop_filter.ref_deltas[i] = reader_.ReadSignedLiteral(6);
+      }
+
+      for (size_t i = 0; i < Vp9LoopFilterParams::kNumModeDeltas; i++) {
+        loop_filter.update_mode_deltas[i] = reader_.ReadBool();
+        if (loop_filter.update_mode_deltas[i])
+          loop_filter.mode_deltas[i] = reader_.ReadLiteral(6);
+      }
+    }
+  }
+}
+
+// 6.2.9 Quantization params syntax
+void Vp9UncompressedHeaderParser::ReadQuantizationParams(
+    Vp9QuantizationParams* quants) {
+  quants->base_q_idx = reader_.ReadLiteral(8);
+
+  quants->delta_q_y_dc = ReadDeltaQ();
+  quants->delta_q_uv_dc = ReadDeltaQ();
+  quants->delta_q_uv_ac = ReadDeltaQ();
+}
+
+// 6.2.10 Delta quantizer syntax
+int8_t Vp9UncompressedHeaderParser::ReadDeltaQ() {
+  if (reader_.ReadBool())
+    return reader_.ReadSignedLiteral(4);
+  return 0;
+}
+
+// 6.2.11 Segmentation params syntax
+bool Vp9UncompressedHeaderParser::ReadSegmentationParams() {
+  Vp9SegmentationParams& segmentation = context_->segmentation;
+  segmentation.update_map = false;
+  segmentation.update_data = false;
+
+  segmentation.enabled = reader_.ReadBool();
+  if (!segmentation.enabled)
+    return true;
+
+  segmentation.update_map = reader_.ReadBool();
+  if (segmentation.update_map) {
+    for (auto& tree_prob : segmentation.tree_probs) {
+      tree_prob = ReadProb();
+    }
+
+    segmentation.temporal_update = reader_.ReadBool();
+    for (auto& pred_prob : segmentation.pred_probs) {
+      pred_prob = segmentation.temporal_update ? ReadProb() : kVp9MaxProb;
+    }
+  }
+
+  segmentation.update_data = reader_.ReadBool();
+  if (segmentation.update_data) {
+    segmentation.abs_or_delta_update = reader_.ReadBool();
+
+    const int kFeatureDataBits[] = {8, 6, 2, 0};
+    const bool kFeatureDataSigned[] = {true, true, false, false};
+
+    for (size_t i = 0; i < Vp9SegmentationParams::kNumSegments; i++) {
+      for (size_t j = 0; j < Vp9SegmentationParams::SEG_LVL_MAX; j++) {
+        int16_t data = 0;
+        segmentation.feature_enabled[i][j] = reader_.ReadBool();
+        if (segmentation.feature_enabled[i][j]) {
+          data = reader_.ReadLiteral(kFeatureDataBits[j]);
+          if (kFeatureDataSigned[j])
+            if (reader_.ReadBool()) {
+              // 7.2.9
+              if (segmentation.abs_or_delta_update) {
+                DVLOG(1) << "feature_sign should be 0"
+                         << " if abs_or_delta_update is 1";
+                return false;
+              }
+              data = -data;
+            }
+        }
+        segmentation.feature_data[i][j] = data;
+      }
+    }
+  }
+  return true;
+}
+
+// 6.2.12 Probability syntax
+uint8_t Vp9UncompressedHeaderParser::ReadProb() {
+  return reader_.ReadBool() ? reader_.ReadLiteral(8) : kVp9MaxProb;
+}
+
+// 6.2.13 Tile info syntax
+bool Vp9UncompressedHeaderParser::ReadTileInfo(Vp9FrameHeader* fhdr) {
+  int sb64_cols = (fhdr->frame_width + 63) / 64;
+
+  int min_log2_tile_cols = GetMinLog2TileCols(sb64_cols);
+  int max_log2_tile_cols = GetMaxLog2TileCols(sb64_cols);
+
+  int max_ones = max_log2_tile_cols - min_log2_tile_cols;
+  fhdr->tile_cols_log2 = min_log2_tile_cols;
+  while (max_ones-- && reader_.ReadBool())
+    fhdr->tile_cols_log2++;
+
+  fhdr->tile_rows_log2 = reader_.ReadBool() ? 1 : 0;
+  if (fhdr->tile_rows_log2 > 0 && reader_.ReadBool())
+    fhdr->tile_rows_log2++;
+
+  // 7.2.11 Tile info semantics
+  if (fhdr->tile_cols_log2 > 6) {
+    VLOG(1) << "tile_cols_log2 should be <= 6";
+    return false;
+  }
+
+  return true;
+}
+
+void Vp9UncompressedHeaderParser::ResetLoopfilter() {
+  Vp9LoopFilterParams& loop_filter = context_->loop_filter;
+
+  loop_filter.delta_enabled = true;
+  loop_filter.delta_update = true;
+
+  loop_filter.ref_deltas[VP9_FRAME_INTRA] = 1;
+  loop_filter.ref_deltas[VP9_FRAME_LAST] = 0;
+  loop_filter.ref_deltas[VP9_FRAME_GOLDEN] = -1;
+  loop_filter.ref_deltas[VP9_FRAME_ALTREF] = -1;
+
+  memset(loop_filter.mode_deltas, 0, sizeof(loop_filter.mode_deltas));
+}
+
+// 6.2 Uncompressed header syntax
+bool Vp9UncompressedHeaderParser::Parse(const uint8_t* stream,
+                                        off_t frame_size,
+                                        Vp9FrameHeader* fhdr) {
+  DVLOG(2) << "UncompressedHeaderParser::Parse";
+  reader_.Initialize(stream, frame_size);
+
+  fhdr->data = stream;
+  fhdr->frame_size = frame_size;
+
+  // frame marker
+  if (reader_.ReadLiteral(2) != 0x2) {
+    DVLOG(1) << "frame marker shall be equal to 2";
+    return false;
+  }
+
+  fhdr->profile = ReadProfile();
+  if (fhdr->profile >= kVp9MaxProfile) {
+    DVLOG(1) << "Unsupported bitstream profile";
+    return false;
+  }
+
+  fhdr->show_existing_frame = reader_.ReadBool();
+  if (fhdr->show_existing_frame) {
+    fhdr->frame_to_show_map_idx = reader_.ReadLiteral(3);
+    fhdr->show_frame = true;
+
+    if (!reader_.ConsumeTrailingBits()) {
+      DVLOG(1) << "trailing bits are not zero";
+      return false;
+    }
+    if (!reader_.IsValid()) {
+      DVLOG(1) << "parser reads beyond the end of buffer";
+      return false;
+    }
+    fhdr->uncompressed_header_size = reader_.GetBytesRead();
+    fhdr->header_size_in_bytes = 0;
+    return true;
+  }
+
+  fhdr->frame_type = static_cast<Vp9FrameHeader::FrameType>(reader_.ReadBool());
+  fhdr->show_frame = reader_.ReadBool();
+  fhdr->error_resilient_mode = reader_.ReadBool();
+
+  if (fhdr->IsKeyframe()) {
+    if (!VerifySyncCode())
+      return false;
+
+    if (!ReadColorConfig(fhdr))
+      return false;
+
+    ReadFrameSize(fhdr);
+    ReadRenderSize(fhdr);
+    fhdr->refresh_frame_flags = 0xff;
+  } else {
+    if (!fhdr->show_frame)
+      fhdr->intra_only = reader_.ReadBool();
+
+    if (!fhdr->error_resilient_mode)
+      fhdr->reset_frame_context = reader_.ReadLiteral(2);
+
+    if (fhdr->intra_only) {
+      if (!VerifySyncCode())
+        return false;
+
+      if (fhdr->profile > 0) {
+        if (!ReadColorConfig(fhdr))
+          return false;
+      } else {
+        fhdr->bit_depth = 8;
+        fhdr->color_space = Vp9ColorSpace::BT_601;
+        fhdr->subsampling_x = fhdr->subsampling_y = 1;
+      }
+
+      fhdr->refresh_frame_flags = reader_.ReadLiteral(8);
+
+      ReadFrameSize(fhdr);
+      ReadRenderSize(fhdr);
+    } else {
+      fhdr->refresh_frame_flags = reader_.ReadLiteral(8);
+
+      static_assert(arraysize(fhdr->ref_frame_sign_bias) >=
+                        Vp9FrameType::VP9_FRAME_LAST + kVp9NumRefsPerFrame,
+                    "ref_frame_sign_bias is not big enough");
+      for (size_t i = 0; i < kVp9NumRefsPerFrame; i++) {
+        fhdr->ref_frame_idx[i] = reader_.ReadLiteral(kVp9NumRefFramesLog2);
+        fhdr->ref_frame_sign_bias[Vp9FrameType::VP9_FRAME_LAST + i] =
+            reader_.ReadBool();
+
+        // 8.2 Frame order constraints
+        // ref_frame_idx[i] refers to an earlier decoded frame.
+        const Vp9Parser::ReferenceSlot& ref =
+            context_->ref_slots[fhdr->ref_frame_idx[i]];
+        if (!ref.initialized) {
+          DVLOG(1) << "ref_frame_idx[" << i
+                   << "]=" << static_cast<int>(fhdr->ref_frame_idx[i])
+                   << " refers to unused frame";
+          return false;
+        }
+
+        // 7.2 Uncompressed header semantics
+        // the selected reference frames match the current frame in bit depth,
+        // profile, chroma subsampling, and color space.
+        // TODO(kcwu): how about color_range?
+        if (ref.profile != fhdr->profile) {
+          DVLOG(1) << "profile of referenced frame mismatch";
+          return false;
+        }
+        if (i == 0) {
+          // Some fields are not specified for inter-frame in header, so copy
+          // them from referenced frame.
+          fhdr->bit_depth = ref.bit_depth;
+          fhdr->color_space = ref.color_space;
+          fhdr->subsampling_x = ref.subsampling_x;
+          fhdr->subsampling_y = ref.subsampling_y;
+        } else {
+          if (fhdr->bit_depth != ref.bit_depth) {
+            DVLOG(1) << "bit_depth of referenced frame mismatch";
+            return false;
+          }
+          if (fhdr->color_space != ref.color_space) {
+            DVLOG(1) << "color_space of referenced frame mismatch";
+            return false;
+          }
+          if (fhdr->subsampling_x != ref.subsampling_x ||
+              fhdr->subsampling_y != ref.subsampling_y) {
+            DVLOG(1) << "chroma subsampling of referenced frame mismatch";
+            return false;
+          }
+        }
+      }
+
+      if (!ReadFrameSizeFromRefs(fhdr))
+        return false;
+
+      fhdr->allow_high_precision_mv = reader_.ReadBool();
+      fhdr->interpolation_filter = ReadInterpolationFilter();
+    }
+  }
+
+  if (fhdr->error_resilient_mode) {
+    fhdr->refresh_frame_context = false;
+    fhdr->frame_parallel_decoding_mode = true;
+  } else {
+    fhdr->refresh_frame_context = reader_.ReadBool();
+    fhdr->frame_parallel_decoding_mode = reader_.ReadBool();
+  }
+
+  fhdr->frame_context_idx_backup = fhdr->frame_context_idx =
+      reader_.ReadLiteral(2);
+
+  if (fhdr->IsIntra()) {
+    SetupPastIndependence(fhdr);
+    if (fhdr->IsKeyframe() || fhdr->error_resilient_mode ||
+        fhdr->reset_frame_context == 3) {
+      for (auto& frame_context_manage : context_->frame_context_managers)
+        frame_context_manage.Update(fhdr->frame_context);
+    } else if (fhdr->reset_frame_context == 2) {
+      DCHECK_LT(fhdr->frame_context_idx,
+                arraysize(context_->frame_context_managers));
+      context_->frame_context_managers[fhdr->frame_context_idx].Update(
+          fhdr->frame_context);
+    }
+    fhdr->frame_context_idx = 0;
+  }
+
+  ReadLoopFilterParams();
+  ReadQuantizationParams(&fhdr->quant_params);
+  if (!ReadSegmentationParams())
+    return false;
+
+  if (!ReadTileInfo(fhdr))
+    return false;
+
+  fhdr->header_size_in_bytes = reader_.ReadLiteral(16);
+  if (fhdr->header_size_in_bytes == 0) {
+    DVLOG(1) << "invalid header size";
+    return false;
+  }
+
+  if (!reader_.ConsumeTrailingBits()) {
+    DVLOG(1) << "trailing bits are not zero";
+    return false;
+  }
+  if (!reader_.IsValid()) {
+    DVLOG(1) << "parser reads beyond the end of buffer";
+    return false;
+  }
+  fhdr->uncompressed_header_size = reader_.GetBytesRead();
+
+  return true;
+}
+
+}  // namespace media