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/*
* Copyright (c) 2016 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 "common_video/h264/pps_parser.h"
#include "common_video/h264/h264_common.h"
#include "rtc_base/bit_buffer.h"
#include "rtc_base/buffer.h"
#include "rtc_base/checks.h"
#include "test/gtest.h"
namespace webrtc {
namespace {
// Contains enough of the image slice to contain slice QP.
const uint8_t kH264BitstreamChunk[] = {
0x00, 0x00, 0x00, 0x01, 0x67, 0x42, 0x80, 0x20, 0xda, 0x01, 0x40, 0x16,
0xe8, 0x06, 0xd0, 0xa1, 0x35, 0x00, 0x00, 0x00, 0x01, 0x68, 0xce, 0x06,
0xe2, 0x00, 0x00, 0x00, 0x01, 0x65, 0xb8, 0x40, 0xf0, 0x8c, 0x03, 0xf2,
0x75, 0x67, 0xad, 0x41, 0x64, 0x24, 0x0e, 0xa0, 0xb2, 0x12, 0x1e, 0xf8,
};
const size_t kPpsBufferMaxSize = 256;
const uint32_t kIgnored = 0;
} // namespace
void WritePps(const PpsParser::PpsState& pps,
int slice_group_map_type,
int num_slice_groups,
int pic_size_in_map_units,
rtc::Buffer* out_buffer) {
uint8_t data[kPpsBufferMaxSize] = {0};
rtc::BitBufferWriter bit_buffer(data, kPpsBufferMaxSize);
// pic_parameter_set_id: ue(v)
bit_buffer.WriteExponentialGolomb(pps.id);
// seq_parameter_set_id: ue(v)
bit_buffer.WriteExponentialGolomb(pps.sps_id);
// entropy_coding_mode_flag: u(1)
bit_buffer.WriteBits(pps.entropy_coding_mode_flag, 1);
// bottom_field_pic_order_in_frame_present_flag: u(1)
bit_buffer.WriteBits(pps.bottom_field_pic_order_in_frame_present_flag ? 1 : 0,
1);
// num_slice_groups_minus1: ue(v)
RTC_CHECK_GT(num_slice_groups, 0);
bit_buffer.WriteExponentialGolomb(num_slice_groups - 1);
if (num_slice_groups > 1) {
// slice_group_map_type: ue(v)
bit_buffer.WriteExponentialGolomb(slice_group_map_type);
switch (slice_group_map_type) {
case 0:
for (int i = 0; i < num_slice_groups; ++i) {
// run_length_minus1[iGroup]: ue(v)
bit_buffer.WriteExponentialGolomb(kIgnored);
}
break;
case 2:
for (int i = 0; i < num_slice_groups; ++i) {
// top_left[iGroup]: ue(v)
bit_buffer.WriteExponentialGolomb(kIgnored);
// bottom_right[iGroup]: ue(v)
bit_buffer.WriteExponentialGolomb(kIgnored);
}
break;
case 3:
case 4:
case 5:
// slice_group_change_direction_flag: u(1)
bit_buffer.WriteBits(kIgnored, 1);
// slice_group_change_rate_minus1: ue(v)
bit_buffer.WriteExponentialGolomb(kIgnored);
break;
case 6: {
bit_buffer.WriteExponentialGolomb(pic_size_in_map_units - 1);
uint32_t slice_group_id_bits = 0;
// If num_slice_groups is not a power of two an additional bit is
// required
// to account for the ceil() of log2() below.
if ((num_slice_groups & (num_slice_groups - 1)) != 0)
++slice_group_id_bits;
while (num_slice_groups > 0) {
num_slice_groups >>= 1;
++slice_group_id_bits;
}
for (int i = 0; i < pic_size_in_map_units; ++i) {
// slice_group_id[i]: u(v)
// Represented by ceil(log2(num_slice_groups_minus1 + 1)) bits.
bit_buffer.WriteBits(kIgnored, slice_group_id_bits);
}
break;
}
default:
RTC_DCHECK_NOTREACHED();
}
}
// num_ref_idx_l0_default_active_minus1: ue(v)
bit_buffer.WriteExponentialGolomb(kIgnored);
// num_ref_idx_l1_default_active_minus1: ue(v)
bit_buffer.WriteExponentialGolomb(kIgnored);
// weighted_pred_flag: u(1)
bit_buffer.WriteBits(pps.weighted_pred_flag ? 1 : 0, 1);
// weighted_bipred_idc: u(2)
bit_buffer.WriteBits(pps.weighted_bipred_idc, 2);
// pic_init_qp_minus26: se(v)
bit_buffer.WriteSignedExponentialGolomb(pps.pic_init_qp_minus26);
// pic_init_qs_minus26: se(v)
bit_buffer.WriteExponentialGolomb(kIgnored);
// chroma_qp_index_offset: se(v)
bit_buffer.WriteExponentialGolomb(kIgnored);
// deblocking_filter_control_present_flag: u(1)
// constrained_intra_pred_flag: u(1)
bit_buffer.WriteBits(kIgnored, 2);
// redundant_pic_cnt_present_flag: u(1)
bit_buffer.WriteBits(pps.redundant_pic_cnt_present_flag, 1);
size_t byte_offset;
size_t bit_offset;
bit_buffer.GetCurrentOffset(&byte_offset, &bit_offset);
if (bit_offset > 0) {
bit_buffer.WriteBits(0, 8 - bit_offset);
bit_buffer.GetCurrentOffset(&byte_offset, &bit_offset);
}
H264::WriteRbsp(data, byte_offset, out_buffer);
}
class PpsParserTest : public ::testing::Test {
public:
PpsParserTest() {}
~PpsParserTest() override {}
void RunTest() {
VerifyParsing(generated_pps_, 0, 1, 0);
const int kMaxSliceGroups = 17; // Arbitrarily large.
const int kMaxMapType = 6;
int slice_group_bits = 0;
for (int slice_group = 2; slice_group < kMaxSliceGroups; ++slice_group) {
if ((slice_group & (slice_group - 1)) == 0) {
// Slice group at a new power of two - increase slice_group_bits.
++slice_group_bits;
}
for (int map_type = 0; map_type <= kMaxMapType; ++map_type) {
if (map_type == 1) {
// TODO(sprang): Implement support for dispersed slice group map type.
// See 8.2.2.2 Specification for dispersed slice group map type.
continue;
} else if (map_type == 6) {
int max_pic_size = 1 << slice_group_bits;
for (int pic_size = 1; pic_size < max_pic_size; ++pic_size)
VerifyParsing(generated_pps_, map_type, slice_group, pic_size);
} else {
VerifyParsing(generated_pps_, map_type, slice_group, 0);
}
}
}
}
void VerifyParsing(const PpsParser::PpsState& pps,
int slice_group_map_type,
int num_slice_groups,
int pic_size_in_map_units) {
buffer_.Clear();
WritePps(pps, slice_group_map_type, num_slice_groups, pic_size_in_map_units,
&buffer_);
parsed_pps_ = PpsParser::ParsePps(buffer_.data(), buffer_.size());
ASSERT_TRUE(parsed_pps_);
EXPECT_EQ(pps.bottom_field_pic_order_in_frame_present_flag,
parsed_pps_->bottom_field_pic_order_in_frame_present_flag);
EXPECT_EQ(pps.weighted_pred_flag, parsed_pps_->weighted_pred_flag);
EXPECT_EQ(pps.weighted_bipred_idc, parsed_pps_->weighted_bipred_idc);
EXPECT_EQ(pps.entropy_coding_mode_flag,
parsed_pps_->entropy_coding_mode_flag);
EXPECT_EQ(pps.redundant_pic_cnt_present_flag,
parsed_pps_->redundant_pic_cnt_present_flag);
EXPECT_EQ(pps.pic_init_qp_minus26, parsed_pps_->pic_init_qp_minus26);
EXPECT_EQ(pps.id, parsed_pps_->id);
EXPECT_EQ(pps.sps_id, parsed_pps_->sps_id);
}
PpsParser::PpsState generated_pps_;
rtc::Buffer buffer_;
absl::optional<PpsParser::PpsState> parsed_pps_;
};
TEST_F(PpsParserTest, ZeroPps) {
RunTest();
}
TEST_F(PpsParserTest, MaxPps) {
generated_pps_.bottom_field_pic_order_in_frame_present_flag = true;
generated_pps_.pic_init_qp_minus26 = 25;
generated_pps_.redundant_pic_cnt_present_flag = 1; // 1 bit value.
generated_pps_.weighted_bipred_idc = (1 << 2) - 1; // 2 bit value.
generated_pps_.weighted_pred_flag = true;
generated_pps_.entropy_coding_mode_flag = true;
generated_pps_.id = 2;
generated_pps_.sps_id = 1;
RunTest();
generated_pps_.pic_init_qp_minus26 = -25;
RunTest();
}
TEST_F(PpsParserTest, PpsIdFromSlice) {
absl::optional<uint32_t> pps_id = PpsParser::ParsePpsIdFromSlice(
kH264BitstreamChunk, sizeof(kH264BitstreamChunk));
ASSERT_TRUE(pps_id);
EXPECT_EQ(2u, *pps_id);
}
} // namespace webrtc
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