| /* | 
 |  *  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 <vector> | 
 |  | 
 | #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) { | 
 |   std::vector<H264::NaluIndex> nalu_indices = | 
 |       H264::FindNaluIndices(kH264BitstreamChunk, sizeof(kH264BitstreamChunk)); | 
 |   EXPECT_EQ(nalu_indices.size(), 3ull); | 
 |   for (const auto& index : nalu_indices) { | 
 |     H264::NaluType nalu_type = | 
 |         H264::ParseNaluType(kH264BitstreamChunk[index.payload_start_offset]); | 
 |     if (nalu_type == H264::NaluType::kIdr) { | 
 |       absl::optional<uint32_t> pps_id = PpsParser::ParsePpsIdFromSlice( | 
 |           kH264BitstreamChunk + index.payload_start_offset, index.payload_size); | 
 |       EXPECT_EQ(pps_id, 0u); | 
 |       break; | 
 |     } | 
 |   } | 
 | } | 
 |  | 
 | }  // namespace webrtc |