blob: 808fdd3087091eb58a1a233f1bbd5e0cd7062634 [file] [log] [blame]
/*
* Copyright (c) 2017 The WebRTC 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.
*/
#include "modules/video_coding/utility/vp9_uncompressed_header_parser.h"
#include "rtc_base/bitbuffer.h"
#include "rtc_base/logging.h"
namespace webrtc {
#define RETURN_FALSE_IF_ERROR(x) \
if (!(x)) { \
return false; \
}
namespace vp9 {
namespace {
const size_t kVp9NumRefsPerFrame = 3;
const size_t kVp9MaxRefLFDeltas = 4;
const size_t kVp9MaxModeLFDeltas = 2;
bool Vp9ReadProfile(rtc::BitBuffer* br, uint8_t* profile) {
uint32_t high_bit;
uint32_t low_bit;
RETURN_FALSE_IF_ERROR(br->ReadBits(&low_bit, 1));
RETURN_FALSE_IF_ERROR(br->ReadBits(&high_bit, 1));
*profile = (high_bit << 1) + low_bit;
if (*profile > 2) {
uint32_t reserved_bit;
RETURN_FALSE_IF_ERROR(br->ReadBits(&reserved_bit, 1));
if (reserved_bit) {
RTC_LOG(LS_WARNING) << "Failed to get QP. Unsupported bitstream profile.";
return false;
}
}
return true;
}
bool Vp9ReadSyncCode(rtc::BitBuffer* br) {
uint32_t sync_code;
RETURN_FALSE_IF_ERROR(br->ReadBits(&sync_code, 24));
if (sync_code != 0x498342) {
RTC_LOG(LS_WARNING) << "Failed to get QP. Invalid sync code.";
return false;
}
return true;
}
bool Vp9ReadColorConfig(rtc::BitBuffer* br, uint8_t profile) {
if (profile == 2 || profile == 3) {
// Bitdepth.
RETURN_FALSE_IF_ERROR(br->ConsumeBits(1));
}
uint32_t color_space;
RETURN_FALSE_IF_ERROR(br->ReadBits(&color_space, 3));
// SRGB is 7.
if (color_space != 7) {
// YUV range flag.
RETURN_FALSE_IF_ERROR(br->ConsumeBits(1));
if (profile == 1 || profile == 3) {
// 1 bit: subsampling x.
// 1 bit: subsampling y.
RETURN_FALSE_IF_ERROR(br->ConsumeBits(2));
uint32_t reserved_bit;
RETURN_FALSE_IF_ERROR(br->ReadBits(&reserved_bit, 1));
if (reserved_bit) {
RTC_LOG(LS_WARNING) << "Failed to get QP. Reserved bit set.";
return false;
}
}
} else {
if (profile == 1 || profile == 3) {
uint32_t reserved_bit;
RETURN_FALSE_IF_ERROR(br->ReadBits(&reserved_bit, 1));
if (reserved_bit) {
RTC_LOG(LS_WARNING) << "Failed to get QP. Reserved bit set.";
return false;
}
} else {
RTC_LOG(LS_WARNING) << "Failed to get QP. 4:4:4 color not supported in "
"profile 0 or 2.";
return false;
}
}
return true;
}
bool Vp9ReadFrameSize(rtc::BitBuffer* br) {
// 2 bytes: frame width.
// 2 bytes: frame height.
return br->ConsumeBytes(4);
}
bool Vp9ReadRenderSize(rtc::BitBuffer* br) {
uint32_t bit;
RETURN_FALSE_IF_ERROR(br->ReadBits(&bit, 1));
if (bit) {
// 2 bytes: render width.
// 2 bytes: render height.
RETURN_FALSE_IF_ERROR(br->ConsumeBytes(4));
}
return true;
}
bool Vp9ReadFrameSizeFromRefs(rtc::BitBuffer* br) {
uint32_t found_ref = 0;
for (size_t i = 0; i < kVp9NumRefsPerFrame; i++) {
// Size in refs.
RETURN_FALSE_IF_ERROR(br->ReadBits(&found_ref, 1));
if (found_ref)
break;
}
if (!found_ref) {
if (!Vp9ReadFrameSize(br)) {
return false;
}
}
return Vp9ReadRenderSize(br);
}
bool Vp9ReadInterpolationFilter(rtc::BitBuffer* br) {
uint32_t bit;
RETURN_FALSE_IF_ERROR(br->ReadBits(&bit, 1));
if (bit)
return true;
return br->ConsumeBits(2);
}
bool Vp9ReadLoopfilter(rtc::BitBuffer* br) {
// 6 bits: filter level.
// 3 bits: sharpness level.
RETURN_FALSE_IF_ERROR(br->ConsumeBits(9));
uint32_t mode_ref_delta_enabled;
RETURN_FALSE_IF_ERROR(br->ReadBits(&mode_ref_delta_enabled, 1));
if (mode_ref_delta_enabled) {
uint32_t mode_ref_delta_update;
RETURN_FALSE_IF_ERROR(br->ReadBits(&mode_ref_delta_update, 1));
if (mode_ref_delta_update) {
uint32_t bit;
for (size_t i = 0; i < kVp9MaxRefLFDeltas; i++) {
RETURN_FALSE_IF_ERROR(br->ReadBits(&bit, 1));
if (bit) {
RETURN_FALSE_IF_ERROR(br->ConsumeBits(7));
}
}
for (size_t i = 0; i < kVp9MaxModeLFDeltas; i++) {
RETURN_FALSE_IF_ERROR(br->ReadBits(&bit, 1));
if (bit) {
RETURN_FALSE_IF_ERROR(br->ConsumeBits(7));
}
}
}
}
return true;
}
} // namespace
bool GetQp(const uint8_t* buf, size_t length, int* qp) {
rtc::BitBuffer br(buf, length);
// Frame marker.
uint32_t frame_marker;
RETURN_FALSE_IF_ERROR(br.ReadBits(&frame_marker, 2));
if (frame_marker != 0x2) {
RTC_LOG(LS_WARNING) << "Failed to get QP. Frame marker should be 2.";
return false;
}
// Profile.
uint8_t profile;
if (!Vp9ReadProfile(&br, &profile))
return false;
// Show existing frame.
uint32_t show_existing_frame;
RETURN_FALSE_IF_ERROR(br.ReadBits(&show_existing_frame, 1));
if (show_existing_frame)
return false;
// Frame type: KEY_FRAME(0), INTER_FRAME(1).
uint32_t frame_type;
uint32_t show_frame;
uint32_t error_resilient;
RETURN_FALSE_IF_ERROR(br.ReadBits(&frame_type, 1));
RETURN_FALSE_IF_ERROR(br.ReadBits(&show_frame, 1));
RETURN_FALSE_IF_ERROR(br.ReadBits(&error_resilient, 1));
if (!frame_type) {
if (!Vp9ReadSyncCode(&br))
return false;
if (!Vp9ReadColorConfig(&br, profile))
return false;
if (!Vp9ReadFrameSize(&br))
return false;
if (!Vp9ReadRenderSize(&br))
return false;
} else {
uint32_t intra_only = 0;
if (!show_frame)
RETURN_FALSE_IF_ERROR(br.ReadBits(&intra_only, 1));
if (!error_resilient)
RETURN_FALSE_IF_ERROR(br.ConsumeBits(2)); // Reset frame context.
if (intra_only) {
if (!Vp9ReadSyncCode(&br))
return false;
if (profile > 0) {
if (!Vp9ReadColorConfig(&br, profile))
return false;
}
// Refresh frame flags.
RETURN_FALSE_IF_ERROR(br.ConsumeBits(8));
if (!Vp9ReadFrameSize(&br))
return false;
if (!Vp9ReadRenderSize(&br))
return false;
} else {
// Refresh frame flags.
RETURN_FALSE_IF_ERROR(br.ConsumeBits(8));
for (size_t i = 0; i < kVp9NumRefsPerFrame; i++) {
// 3 bits: Ref frame index.
// 1 bit: Ref frame sign biases.
RETURN_FALSE_IF_ERROR(br.ConsumeBits(4));
}
if (!Vp9ReadFrameSizeFromRefs(&br))
return false;
// Allow high precision mv.
RETURN_FALSE_IF_ERROR(br.ConsumeBits(1));
// Interpolation filter.
if (!Vp9ReadInterpolationFilter(&br))
return false;
}
}
if (!error_resilient) {
// 1 bit: Refresh frame context.
// 1 bit: Frame parallel decoding mode.
RETURN_FALSE_IF_ERROR(br.ConsumeBits(2));
}
// Frame context index.
RETURN_FALSE_IF_ERROR(br.ConsumeBits(2));
if (!Vp9ReadLoopfilter(&br))
return false;
// Base QP.
uint8_t base_q0;
RETURN_FALSE_IF_ERROR(br.ReadUInt8(&base_q0));
*qp = base_q0;
return true;
}
} // namespace vp9
} // namespace webrtc