// Copyright 2015 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.
//
// This file contains an implementation of a VP9 bitstream parser.
//
// VERBOSE level:
// 1 something wrong in bitstream
// 2 parsing steps
// 3 parsed values (selected)
// Note: ported from Chromium commit head: 2de6929
#include "vp9_parser.h"
#include <algorithm>
#include "base/bind.h"
#include "base/logging.h"
#include "base/macros.h"
#include "base/numerics/safe_conversions.h"
#include "vp9_compressed_header_parser.h"
#include "vp9_uncompressed_header_parser.h"
namespace media {
namespace {
// Coefficients extracted verbatim from "VP9 Bitstream & Decoding Process
// Specification" Version 0.6, Sec 8.6.1 Dequantization functions, see:
// https://www.webmproject.org/vp9/#draft-vp9-bitstream-and-decoding-process-specification
constexpr size_t kQIndexRange = 256;
// clang-format off
// libva is the only user of high bit depth VP9 formats and only supports
// 10 bits per component, see https://github.com/01org/libva/issues/137.
// TODO(mcasas): Add the 12 bit versions of these tables.
const int16_t kDcQLookup[][kQIndexRange] = {
{
4, 8, 8, 9, 10, 11, 12, 12, 13, 14, 15, 16,
17, 18, 19, 19, 20, 21, 22, 23, 24, 25, 26, 26,
27, 28, 29, 30, 31, 32, 32, 33, 34, 35, 36, 37,
38, 38, 39, 40, 41, 42, 43, 43, 44, 45, 46, 47,
48, 48, 49, 50, 51, 52, 53, 53, 54, 55, 56, 57,
57, 58, 59, 60, 61, 62, 62, 63, 64, 65, 66, 66,
67, 68, 69, 70, 70, 71, 72, 73, 74, 74, 75, 76,
77, 78, 78, 79, 80, 81, 81, 82, 83, 84, 85, 85,
87, 88, 90, 92, 93, 95, 96, 98, 99, 101, 102, 104,
105, 107, 108, 110, 111, 113, 114, 116, 117, 118, 120, 121,
123, 125, 127, 129, 131, 134, 136, 138, 140, 142, 144, 146,
148, 150, 152, 154, 156, 158, 161, 164, 166, 169, 172, 174,
177, 180, 182, 185, 187, 190, 192, 195, 199, 202, 205, 208,
211, 214, 217, 220, 223, 226, 230, 233, 237, 240, 243, 247,
250, 253, 257, 261, 265, 269, 272, 276, 280, 284, 288, 292,
296, 300, 304, 309, 313, 317, 322, 326, 330, 335, 340, 344,
349, 354, 359, 364, 369, 374, 379, 384, 389, 395, 400, 406,
411, 417, 423, 429, 435, 441, 447, 454, 461, 467, 475, 482,
489, 497, 505, 513, 522, 530, 539, 549, 559, 569, 579, 590,
602, 614, 626, 640, 654, 668, 684, 700, 717, 736, 755, 775,
796, 819, 843, 869, 896, 925, 955, 988, 1022, 1058, 1098, 1139,
1184, 1232, 1282, 1336,
},
{
4, 9, 10, 13, 15, 17, 20, 22, 25, 28, 31, 34,
37, 40, 43, 47, 50, 53, 57, 60, 64, 68, 71, 75,
78, 82, 86, 90, 93, 97, 101, 105, 109, 113, 116, 120,
124, 128, 132, 136, 140, 143, 147, 151, 155, 159, 163, 166,
170, 174, 178, 182, 185, 189, 193, 197, 200, 204, 208, 212,
215, 219, 223, 226, 230, 233, 237, 241, 244, 248, 251, 255,
259, 262, 266, 269, 273, 276, 280, 283, 287, 290, 293, 297,
300, 304, 307, 310, 314, 317, 321, 324, 327, 331, 334, 337,
343, 350, 356, 362, 369, 375, 381, 387, 394, 400, 406, 412,
418, 424, 430, 436, 442, 448, 454, 460, 466, 472, 478, 484,
490, 499, 507, 516, 525, 533, 542, 550, 559, 567, 576, 584,
592, 601, 609, 617, 625, 634, 644, 655, 666, 676, 687, 698,
708, 718, 729, 739, 749, 759, 770, 782, 795, 807, 819, 831,
844, 856, 868, 880, 891, 906, 920, 933, 947, 961, 975, 988,
1001, 1015, 1030, 1045, 1061, 1076, 1090, 1105, 1120, 1137, 1153, 1170,
1186, 1202, 1218, 1236, 1253, 1271, 1288, 1306, 1323, 1342, 1361, 1379,
1398, 1416, 1436, 1456, 1476, 1496, 1516, 1537, 1559, 1580, 1601, 1624,
1647, 1670, 1692, 1717, 1741, 1766, 1791, 1817, 1844, 1871, 1900, 1929,
1958, 1990, 2021, 2054, 2088, 2123, 2159, 2197, 2236, 2276, 2319, 2363,
2410, 2458, 2508, 2561, 2616, 2675, 2737, 2802, 2871, 2944, 3020, 3102,
3188, 3280, 3375, 3478, 3586, 3702, 3823, 3953, 4089, 4236, 4394, 4559,
4737, 4929, 5130, 5347
}
};
const int16_t kAcQLookup[][kQIndexRange] = {
{
4, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,
19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,
31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42,
43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54,
55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,
67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78,
79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90,
91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102,
104, 106, 108, 110, 112, 114, 116, 118, 120, 122, 124, 126,
128, 130, 132, 134, 136, 138, 140, 142, 144, 146, 148, 150,
152, 155, 158, 161, 164, 167, 170, 173, 176, 179, 182, 185,
188, 191, 194, 197, 200, 203, 207, 211, 215, 219, 223, 227,
231, 235, 239, 243, 247, 251, 255, 260, 265, 270, 275, 280,
285, 290, 295, 300, 305, 311, 317, 323, 329, 335, 341, 347,
353, 359, 366, 373, 380, 387, 394, 401, 408, 416, 424, 432,
440, 448, 456, 465, 474, 483, 492, 501, 510, 520, 530, 540,
550, 560, 571, 582, 593, 604, 615, 627, 639, 651, 663, 676,
689, 702, 715, 729, 743, 757, 771, 786, 801, 816, 832, 848,
864, 881, 898, 915, 933, 951, 969, 988, 1007, 1026, 1046, 1066,
1087, 1108, 1129, 1151, 1173, 1196, 1219, 1243, 1267, 1292, 1317, 1343,
1369, 1396, 1423, 1451, 1479, 1508, 1537, 1567, 1597, 1628, 1660, 1692,
1725, 1759, 1793, 1828,
},
{
4, 9, 11, 13, 16, 18, 21, 24, 27, 30, 33, 37,
40, 44, 48, 51, 55, 59, 63, 67, 71, 75, 79, 83,
88, 92, 96, 100, 105, 109, 114, 118, 122, 127, 131, 136,
140, 145, 149, 154, 158, 163, 168, 172, 177, 181, 186, 190,
195, 199, 204, 208, 213, 217, 222, 226, 231, 235, 240, 244,
249, 253, 258, 262, 267, 271, 275, 280, 284, 289, 293, 297,
302, 306, 311, 315, 319, 324, 328, 332, 337, 341, 345, 349,
354, 358, 362, 367, 371, 375, 379, 384, 388, 392, 396, 401,
409, 417, 425, 433, 441, 449, 458, 466, 474, 482, 490, 498,
506, 514, 523, 531, 539, 547, 555, 563, 571, 579, 588, 596,
604, 616, 628, 640, 652, 664, 676, 688, 700, 713, 725, 737,
749, 761, 773, 785, 797, 809, 825, 841, 857, 873, 889, 905,
922, 938, 954, 970, 986, 1002, 1018, 1038, 1058, 1078, 1098, 1118,
1138, 1158, 1178, 1198, 1218, 1242, 1266, 1290, 1314, 1338, 1362, 1386,
1411, 1435, 1463, 1491, 1519, 1547, 1575, 1603, 1631, 1663, 1695, 1727,
1759, 1791, 1823, 1859, 1895, 1931, 1967, 2003, 2039, 2079, 2119, 2159,
2199, 2239, 2283, 2327, 2371, 2415, 2459, 2507, 2555, 2603, 2651, 2703,
2755, 2807, 2859, 2915, 2971, 3027, 3083, 3143, 3203, 3263, 3327, 3391,
3455, 3523, 3591, 3659, 3731, 3803, 3876, 3952, 4028, 4104, 4184, 4264,
4348, 4432, 4516, 4604, 4692, 4784, 4876, 4972, 5068, 5168, 5268, 5372,
5476, 5584, 5692, 5804, 5916, 6032, 6148, 6268, 6388, 6512, 6640, 6768,
6900, 7036, 7172, 7312
}
};
// clang-format on
static_assert(arraysize(kDcQLookup[0]) == arraysize(kAcQLookup[0]),
"quantizer lookup arrays of incorrect size");
size_t ClampQ(size_t q) {
return std::min(q, kQIndexRange - 1);
}
int ClampLf(int lf) {
const int kMaxLoopFilterLevel = 63;
return std::min(std::max(0, lf), kMaxLoopFilterLevel);
}
} // namespace
bool Vp9FrameHeader::IsKeyframe() const {
// When show_existing_frame is true, the frame header does not precede an
// actual frame to be decoded, so frame_type does not apply (and is not read
// from the stream).
return !show_existing_frame && frame_type == KEYFRAME;
}
bool Vp9FrameHeader::IsIntra() const {
return !show_existing_frame && (frame_type == KEYFRAME || intra_only);
}
Vp9Parser::FrameInfo::FrameInfo(const uint8_t* ptr, off_t size)
: ptr(ptr), size(size) {}
bool Vp9FrameContext::IsValid() const {
// probs should be in [1, 255] range.
static_assert(sizeof(Vp9Prob) == 1,
"following checks assuming Vp9Prob is single byte");
if (memchr(tx_probs_8x8, 0, sizeof(tx_probs_8x8)))
return false;
if (memchr(tx_probs_16x16, 0, sizeof(tx_probs_16x16)))
return false;
if (memchr(tx_probs_32x32, 0, sizeof(tx_probs_32x32)))
return false;
for (auto& a : coef_probs) {
for (auto& ai : a) {
for (auto& aj : ai) {
for (auto& ak : aj) {
int max_l = (ak == aj[0]) ? 3 : 6;
for (int l = 0; l < max_l; l++) {
for (auto& x : ak[l]) {
if (x == 0)
return false;
}
}
}
}
}
}
if (memchr(skip_prob, 0, sizeof(skip_prob)))
return false;
if (memchr(inter_mode_probs, 0, sizeof(inter_mode_probs)))
return false;
if (memchr(interp_filter_probs, 0, sizeof(interp_filter_probs)))
return false;
if (memchr(is_inter_prob, 0, sizeof(is_inter_prob)))
return false;
if (memchr(comp_mode_prob, 0, sizeof(comp_mode_prob)))
return false;
if (memchr(single_ref_prob, 0, sizeof(single_ref_prob)))
return false;
if (memchr(comp_ref_prob, 0, sizeof(comp_ref_prob)))
return false;
if (memchr(y_mode_probs, 0, sizeof(y_mode_probs)))
return false;
if (memchr(uv_mode_probs, 0, sizeof(uv_mode_probs)))
return false;
if (memchr(partition_probs, 0, sizeof(partition_probs)))
return false;
if (memchr(mv_joint_probs, 0, sizeof(mv_joint_probs)))
return false;
if (memchr(mv_sign_prob, 0, sizeof(mv_sign_prob)))
return false;
if (memchr(mv_class_probs, 0, sizeof(mv_class_probs)))
return false;
if (memchr(mv_class0_bit_prob, 0, sizeof(mv_class0_bit_prob)))
return false;
if (memchr(mv_bits_prob, 0, sizeof(mv_bits_prob)))
return false;
if (memchr(mv_class0_fr_probs, 0, sizeof(mv_class0_fr_probs)))
return false;
if (memchr(mv_fr_probs, 0, sizeof(mv_fr_probs)))
return false;
if (memchr(mv_class0_hp_prob, 0, sizeof(mv_class0_hp_prob)))
return false;
if (memchr(mv_hp_prob, 0, sizeof(mv_hp_prob)))
return false;
return true;
}
Vp9Parser::Context::Vp9FrameContextManager::Vp9FrameContextManager()
: weak_ptr_factory_(this) {}
Vp9Parser::Context::Vp9FrameContextManager::~Vp9FrameContextManager() = default;
const Vp9FrameContext&
Vp9Parser::Context::Vp9FrameContextManager::frame_context() const {
DCHECK(initialized_);
DCHECK(!needs_client_update_);
return frame_context_;
}
void Vp9Parser::Context::Vp9FrameContextManager::Reset() {
initialized_ = false;
needs_client_update_ = false;
weak_ptr_factory_.InvalidateWeakPtrs();
}
void Vp9Parser::Context::Vp9FrameContextManager::SetNeedsClientUpdate() {
DCHECK(!needs_client_update_);
initialized_ = true;
needs_client_update_ = true;
}
Vp9Parser::ContextRefreshCallback
Vp9Parser::Context::Vp9FrameContextManager::GetUpdateCb() {
if (needs_client_update_)
return base::Bind(&Vp9FrameContextManager::UpdateFromClient,
weak_ptr_factory_.GetWeakPtr());
else
return Vp9Parser::ContextRefreshCallback();
}
void Vp9Parser::Context::Vp9FrameContextManager::Update(
const Vp9FrameContext& frame_context) {
// DCHECK because we can trust values from our parser.
DCHECK(frame_context.IsValid());
initialized_ = true;
frame_context_ = frame_context;
// For frame context we are updating, it may be still awaiting previous
// ContextRefreshCallback. Because we overwrite the value of context here and
// previous ContextRefreshCallback no longer matters, invalidate the weak ptr
// to prevent previous ContextRefreshCallback run.
// With this optimization, we may be able to parse more frames while previous
// are still decoding.
weak_ptr_factory_.InvalidateWeakPtrs();
needs_client_update_ = false;
}
void Vp9Parser::Context::Vp9FrameContextManager::UpdateFromClient(
const Vp9FrameContext& frame_context) {
DVLOG(2) << "Got external frame_context update";
DCHECK(needs_client_update_);
if (!frame_context.IsValid()) {
DLOG(ERROR) << "Invalid prob value in frame_context";
return;
}
needs_client_update_ = false;
initialized_ = true;
frame_context_ = frame_context;
}
void Vp9Parser::Context::Reset() {
memset(&segmentation_, 0, sizeof(segmentation_));
memset(&loop_filter_, 0, sizeof(loop_filter_));
memset(&ref_slots_, 0, sizeof(ref_slots_));
for (auto& manager : frame_context_managers_)
manager.Reset();
}
void Vp9Parser::Context::MarkFrameContextForUpdate(size_t frame_context_idx) {
DCHECK_LT(frame_context_idx, arraysize(frame_context_managers_));
frame_context_managers_[frame_context_idx].SetNeedsClientUpdate();
}
void Vp9Parser::Context::UpdateFrameContext(
size_t frame_context_idx,
const Vp9FrameContext& frame_context) {
DCHECK_LT(frame_context_idx, arraysize(frame_context_managers_));
frame_context_managers_[frame_context_idx].Update(frame_context);
}
const Vp9Parser::ReferenceSlot& Vp9Parser::Context::GetRefSlot(
size_t ref_type) const {
DCHECK_LT(ref_type, arraysize(ref_slots_));
return ref_slots_[ref_type];
}
void Vp9Parser::Context::UpdateRefSlot(
size_t ref_type,
const Vp9Parser::ReferenceSlot& ref_slot) {
DCHECK_LT(ref_type, arraysize(ref_slots_));
ref_slots_[ref_type] = ref_slot;
}
Vp9Parser::Vp9Parser(bool parsing_compressed_header)
: parsing_compressed_header_(parsing_compressed_header) {
Reset();
}
Vp9Parser::~Vp9Parser() = default;
void Vp9Parser::SetStream(const uint8_t* stream, off_t stream_size) {
DCHECK(stream);
stream_ = stream;
bytes_left_ = stream_size;
frames_.clear();
}
void Vp9Parser::Reset() {
stream_ = nullptr;
bytes_left_ = 0;
frames_.clear();
curr_frame_info_.Reset();
context_.Reset();
}
bool Vp9Parser::ParseUncompressedHeader(const FrameInfo& frame_info,
Vp9FrameHeader* fhdr,
Result* result) {
memset(&curr_frame_header_, 0, sizeof(curr_frame_header_));
*result = kInvalidStream;
Vp9UncompressedHeaderParser uncompressed_parser(&context_);
if (!uncompressed_parser.Parse(frame_info.ptr, frame_info.size,
&curr_frame_header_)) {
*result = kInvalidStream;
return true;
}
if (curr_frame_header_.header_size_in_bytes == 0) {
// Verify padding bits are zero.
for (off_t i = curr_frame_header_.uncompressed_header_size;
i < frame_info.size; i++) {
if (frame_info.ptr[i] != 0) {
DVLOG(1) << "Padding bits are not zeros.";
*result = kInvalidStream;
return true;
}
}
*fhdr = curr_frame_header_;
*result = kOk;
return true;
}
if (curr_frame_header_.uncompressed_header_size +
curr_frame_header_.header_size_in_bytes >
base::checked_cast<size_t>(frame_info.size)) {
DVLOG(1) << "header_size_in_bytes="
<< curr_frame_header_.header_size_in_bytes
<< " is larger than bytes left in buffer: "
<< frame_info.size - curr_frame_header_.uncompressed_header_size;
*result = kInvalidStream;
return true;
}
return false;
}
bool Vp9Parser::ParseCompressedHeader(const FrameInfo& frame_info,
Result* result) {
*result = kInvalidStream;
size_t frame_context_idx = curr_frame_header_.frame_context_idx;
const Context::Vp9FrameContextManager& context_to_load =
context_.frame_context_managers_[frame_context_idx];
if (!context_to_load.initialized()) {
// 8.2 Frame order constraints
// must load an initialized set of probabilities.
DVLOG(1) << "loading uninitialized frame context, index="
<< frame_context_idx;
*result = kInvalidStream;
return true;
}
if (context_to_load.needs_client_update()) {
DVLOG(3) << "waiting frame_context_idx=" << frame_context_idx
<< " to update";
curr_frame_info_ = frame_info;
*result = kAwaitingRefresh;
return true;
}
curr_frame_header_.initial_frame_context = curr_frame_header_.frame_context =
context_to_load.frame_context();
Vp9CompressedHeaderParser compressed_parser;
if (!compressed_parser.Parse(
frame_info.ptr + curr_frame_header_.uncompressed_header_size,
curr_frame_header_.header_size_in_bytes, &curr_frame_header_)) {
*result = kInvalidStream;
return true;
}
if (curr_frame_header_.refresh_frame_context) {
// In frame parallel mode, we can refresh the context without decoding
// tile data.
if (curr_frame_header_.frame_parallel_decoding_mode) {
context_.UpdateFrameContext(frame_context_idx,
curr_frame_header_.frame_context);
} else {
context_.MarkFrameContextForUpdate(frame_context_idx);
}
}
return false;
}
Vp9Parser::Result Vp9Parser::ParseNextFrame(Vp9FrameHeader* fhdr) {
DCHECK(fhdr);
DVLOG(2) << "ParseNextFrame";
FrameInfo frame_info;
Result result;
// If |curr_frame_info_| is valid, uncompressed header was parsed into
// |curr_frame_header_| and we are awaiting context update to proceed with
// compressed header parsing.
if (curr_frame_info_.IsValid()) {
DCHECK(parsing_compressed_header_);
frame_info = curr_frame_info_;
curr_frame_info_.Reset();
} else {
if (frames_.empty()) {
// No frames to be decoded, if there is no more stream, request more.
if (!stream_)
return kEOStream;
// New stream to be parsed, parse it and fill frames_.
frames_ = ParseSuperframe();
if (frames_.empty()) {
DVLOG(1) << "Failed parsing superframes";
return kInvalidStream;
}
}
frame_info = frames_.front();
frames_.pop_front();
if (ParseUncompressedHeader(frame_info, fhdr, &result))
return result;
}
if (parsing_compressed_header_) {
if (ParseCompressedHeader(frame_info, &result)) {
DCHECK(result != kAwaitingRefresh || curr_frame_info_.IsValid());
return result;
}
}
if (!SetupSegmentationDequant())
return kInvalidStream;
SetupLoopFilter();
UpdateSlots();
*fhdr = curr_frame_header_;
return kOk;
}
Vp9Parser::ContextRefreshCallback Vp9Parser::GetContextRefreshCb(
size_t frame_context_idx) {
DCHECK_LT(frame_context_idx, arraysize(context_.frame_context_managers_));
auto& frame_context_manager =
context_.frame_context_managers_[frame_context_idx];
return frame_context_manager.GetUpdateCb();
}
// Annex B Superframes
std::deque<Vp9Parser::FrameInfo> Vp9Parser::ParseSuperframe() {
const uint8_t* stream = stream_;
off_t bytes_left = bytes_left_;
// Make sure we don't parse stream_ more than once.
stream_ = nullptr;
bytes_left_ = 0;
if (bytes_left < 1)
return std::deque<FrameInfo>();
// If this is a superframe, the last byte in the stream will contain the
// superframe marker. If not, the whole buffer contains a single frame.
uint8_t marker = *(stream + bytes_left - 1);
if ((marker & 0xe0) != 0xc0) {
return {FrameInfo(stream, bytes_left)};
}
DVLOG(1) << "Parsing a superframe";
// The bytes immediately before the superframe marker constitute superframe
// index, which stores information about sizes of each frame in it.
// Calculate its size and set index_ptr to the beginning of it.
size_t num_frames = (marker & 0x7) + 1;
size_t mag = ((marker >> 3) & 0x3) + 1;
off_t index_size = 2 + mag * num_frames;
if (bytes_left < index_size)
return std::deque<FrameInfo>();
const uint8_t* index_ptr = stream + bytes_left - index_size;
if (marker != *index_ptr)
return std::deque<FrameInfo>();
++index_ptr;
bytes_left -= index_size;
// Parse frame information contained in the index and add a pointer to and
// size of each frame to frames.
std::deque<FrameInfo> frames;
for (size_t i = 0; i < num_frames; ++i) {
uint32_t size = 0;
for (size_t j = 0; j < mag; ++j) {
size |= *index_ptr << (j * 8);
++index_ptr;
}
if (base::checked_cast<off_t>(size) > bytes_left) {
DVLOG(1) << "Not enough data in the buffer for frame " << i;
return std::deque<FrameInfo>();
}
frames.push_back(FrameInfo(stream, size));
stream += size;
bytes_left -= size;
DVLOG(1) << "Frame " << i << ", size: " << size;
}
return frames;
}
// 8.6.1 Dequantization functions
size_t Vp9Parser::GetQIndex(const Vp9QuantizationParams& quant,
size_t segid) const {
const Vp9SegmentationParams& segmentation = context_.segmentation();
if (segmentation.FeatureEnabled(segid,
Vp9SegmentationParams::SEG_LVL_ALT_Q)) {
int16_t feature_data =
segmentation.FeatureData(segid, Vp9SegmentationParams::SEG_LVL_ALT_Q);
size_t q_index = segmentation.abs_or_delta_update
? feature_data
: quant.base_q_idx + feature_data;
return ClampQ(q_index);
}
return quant.base_q_idx;
}
// 8.6.1 Dequantization functions
bool Vp9Parser::SetupSegmentationDequant() {
const Vp9QuantizationParams& quant = curr_frame_header_.quant_params;
Vp9SegmentationParams& segmentation = context_.segmentation_;
if (curr_frame_header_.bit_depth > 10) {
DLOG(ERROR) << "bit_depth > 10 is not supported yet, kDcQLookup and "
"kAcQLookup need to be extended";
return false;
}
const size_t bit_depth_index = (curr_frame_header_.bit_depth == 8) ? 0 : 1;
if (segmentation.enabled) {
for (size_t i = 0; i < Vp9SegmentationParams::kNumSegments; ++i) {
const size_t q_index = GetQIndex(quant, i);
segmentation.y_dequant[i][0] =
kDcQLookup[bit_depth_index][ClampQ(q_index + quant.delta_q_y_dc)];
segmentation.y_dequant[i][1] =
kAcQLookup[bit_depth_index][ClampQ(q_index)];
segmentation.uv_dequant[i][0] =
kDcQLookup[bit_depth_index][ClampQ(q_index + quant.delta_q_uv_dc)];
segmentation.uv_dequant[i][1] =
kAcQLookup[bit_depth_index][ClampQ(q_index + quant.delta_q_uv_ac)];
}
} else {
const size_t q_index = quant.base_q_idx;
segmentation.y_dequant[0][0] =
kDcQLookup[bit_depth_index][ClampQ(q_index + quant.delta_q_y_dc)];
segmentation.y_dequant[0][1] = kAcQLookup[bit_depth_index][ClampQ(q_index)];
segmentation.uv_dequant[0][0] =
kDcQLookup[bit_depth_index][ClampQ(q_index + quant.delta_q_uv_dc)];
segmentation.uv_dequant[0][1] =
kAcQLookup[bit_depth_index][ClampQ(q_index + quant.delta_q_uv_ac)];
}
return true;
}
// 8.8.1 Loop filter frame init process
void Vp9Parser::SetupLoopFilter() {
Vp9LoopFilterParams& loop_filter = context_.loop_filter_;
if (!loop_filter.level)
return;
int scale = loop_filter.level < 32 ? 1 : 2;
for (size_t i = 0; i < Vp9SegmentationParams::kNumSegments; ++i) {
int level = loop_filter.level;
const Vp9SegmentationParams& segmentation = context_.segmentation();
if (segmentation.FeatureEnabled(i, Vp9SegmentationParams::SEG_LVL_ALT_LF)) {
int feature_data =
segmentation.FeatureData(i, Vp9SegmentationParams::SEG_LVL_ALT_LF);
level = ClampLf(segmentation.abs_or_delta_update ? feature_data
: level + feature_data);
}
if (!loop_filter.delta_enabled) {
memset(loop_filter.lvl[i], level, sizeof(loop_filter.lvl[i]));
} else {
loop_filter.lvl[i][Vp9RefType::VP9_FRAME_INTRA][0] = ClampLf(
level + loop_filter.ref_deltas[Vp9RefType::VP9_FRAME_INTRA] * scale);
loop_filter.lvl[i][Vp9RefType::VP9_FRAME_INTRA][1] = 0;
for (size_t type = Vp9RefType::VP9_FRAME_LAST;
type < Vp9RefType::VP9_FRAME_MAX; ++type) {
for (size_t mode = 0; mode < Vp9LoopFilterParams::kNumModeDeltas;
++mode) {
loop_filter.lvl[i][type][mode] =
ClampLf(level + loop_filter.ref_deltas[type] * scale +
loop_filter.mode_deltas[mode] * scale);
}
}
}
}
}
void Vp9Parser::UpdateSlots() {
// 8.10 Reference frame update process
for (size_t i = 0; i < kVp9NumRefFrames; i++) {
if (curr_frame_header_.RefreshFlag(i)) {
ReferenceSlot ref_slot;
ref_slot.initialized = true;
ref_slot.frame_width = curr_frame_header_.frame_width;
ref_slot.frame_height = curr_frame_header_.frame_height;
ref_slot.subsampling_x = curr_frame_header_.subsampling_x;
ref_slot.subsampling_y = curr_frame_header_.subsampling_y;
ref_slot.bit_depth = curr_frame_header_.bit_depth;
ref_slot.profile = curr_frame_header_.profile;
ref_slot.color_space = curr_frame_header_.color_space;
context_.UpdateRefSlot(i, ref_slot);
}
}
}
} // namespace media