Index: webrtc/sdk/objc/Framework/Classes/h264_video_toolbox_nalu.cc |
diff --git a/webrtc/sdk/objc/Framework/Classes/h264_video_toolbox_nalu.cc b/webrtc/sdk/objc/Framework/Classes/h264_video_toolbox_nalu.cc |
new file mode 100644 |
index 0000000000000000000000000000000000000000..d48e99066f6811d9db5d891fe4efc37ef3783020 |
--- /dev/null |
+++ b/webrtc/sdk/objc/Framework/Classes/h264_video_toolbox_nalu.cc |
@@ -0,0 +1,365 @@ |
+/* |
+ * Copyright (c) 2015 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 "webrtc/sdk/objc/Framework/Classes/h264_video_toolbox_nalu.h" |
+ |
+#include <CoreFoundation/CoreFoundation.h> |
+#include <memory> |
+#include <vector> |
+ |
+#include "webrtc/base/checks.h" |
+#include "webrtc/base/logging.h" |
+ |
+namespace webrtc { |
+ |
+using H264::kAud; |
+using H264::kSps; |
+using H264::NaluIndex; |
+using H264::NaluType; |
+using H264::ParseNaluType; |
+ |
+const char kAnnexBHeaderBytes[4] = {0, 0, 0, 1}; |
+const size_t kAvccHeaderByteSize = sizeof(uint32_t); |
+ |
+bool H264CMSampleBufferToAnnexBBuffer( |
+ CMSampleBufferRef avcc_sample_buffer, |
+ bool is_keyframe, |
+ rtc::Buffer* annexb_buffer, |
+ webrtc::RTPFragmentationHeader** out_header) { |
+ RTC_DCHECK(avcc_sample_buffer); |
+ RTC_DCHECK(out_header); |
+ *out_header = nullptr; |
+ |
+ // Get format description from the sample buffer. |
+ CMVideoFormatDescriptionRef description = |
+ CMSampleBufferGetFormatDescription(avcc_sample_buffer); |
+ if (description == nullptr) { |
+ LOG(LS_ERROR) << "Failed to get sample buffer's description."; |
+ return false; |
+ } |
+ |
+ // Get parameter set information. |
+ int nalu_header_size = 0; |
+ size_t param_set_count = 0; |
+ OSStatus status = CMVideoFormatDescriptionGetH264ParameterSetAtIndex( |
+ description, 0, nullptr, nullptr, ¶m_set_count, &nalu_header_size); |
+ if (status != noErr) { |
+ LOG(LS_ERROR) << "Failed to get parameter set."; |
+ return false; |
+ } |
+ RTC_CHECK_EQ(nalu_header_size, kAvccHeaderByteSize); |
+ RTC_DCHECK_EQ(param_set_count, 2); |
+ |
+ // Truncate any previous data in the buffer without changing its capacity. |
+ annexb_buffer->SetSize(0); |
+ |
+ size_t nalu_offset = 0; |
+ std::vector<size_t> frag_offsets; |
+ std::vector<size_t> frag_lengths; |
+ |
+ // Place all parameter sets at the front of buffer. |
+ if (is_keyframe) { |
+ size_t param_set_size = 0; |
+ const uint8_t* param_set = nullptr; |
+ for (size_t i = 0; i < param_set_count; ++i) { |
+ status = CMVideoFormatDescriptionGetH264ParameterSetAtIndex( |
+ description, i, ¶m_set, ¶m_set_size, nullptr, nullptr); |
+ if (status != noErr) { |
+ LOG(LS_ERROR) << "Failed to get parameter set."; |
+ return false; |
+ } |
+ // Update buffer. |
+ annexb_buffer->AppendData(kAnnexBHeaderBytes, sizeof(kAnnexBHeaderBytes)); |
+ annexb_buffer->AppendData(reinterpret_cast<const char*>(param_set), |
+ param_set_size); |
+ // Update fragmentation. |
+ frag_offsets.push_back(nalu_offset + sizeof(kAnnexBHeaderBytes)); |
+ frag_lengths.push_back(param_set_size); |
+ nalu_offset += sizeof(kAnnexBHeaderBytes) + param_set_size; |
+ } |
+ } |
+ |
+ // Get block buffer from the sample buffer. |
+ CMBlockBufferRef block_buffer = |
+ CMSampleBufferGetDataBuffer(avcc_sample_buffer); |
+ if (block_buffer == nullptr) { |
+ LOG(LS_ERROR) << "Failed to get sample buffer's block buffer."; |
+ return false; |
+ } |
+ CMBlockBufferRef contiguous_buffer = nullptr; |
+ // Make sure block buffer is contiguous. |
+ if (!CMBlockBufferIsRangeContiguous(block_buffer, 0, 0)) { |
+ status = CMBlockBufferCreateContiguous( |
+ nullptr, block_buffer, nullptr, nullptr, 0, 0, 0, &contiguous_buffer); |
+ if (status != noErr) { |
+ LOG(LS_ERROR) << "Failed to flatten non-contiguous block buffer: " |
+ << status; |
+ return false; |
+ } |
+ } else { |
+ contiguous_buffer = block_buffer; |
+ // Retain to make cleanup easier. |
+ CFRetain(contiguous_buffer); |
+ block_buffer = nullptr; |
+ } |
+ |
+ // Now copy the actual data. |
+ char* data_ptr = nullptr; |
+ size_t block_buffer_size = CMBlockBufferGetDataLength(contiguous_buffer); |
+ status = CMBlockBufferGetDataPointer(contiguous_buffer, 0, nullptr, nullptr, |
+ &data_ptr); |
+ if (status != noErr) { |
+ LOG(LS_ERROR) << "Failed to get block buffer data."; |
+ CFRelease(contiguous_buffer); |
+ return false; |
+ } |
+ size_t bytes_remaining = block_buffer_size; |
+ while (bytes_remaining > 0) { |
+ // The size type here must match |nalu_header_size|, we expect 4 bytes. |
+ // Read the length of the next packet of data. Must convert from big endian |
+ // to host endian. |
+ RTC_DCHECK_GE(bytes_remaining, (size_t)nalu_header_size); |
+ uint32_t* uint32_data_ptr = reinterpret_cast<uint32_t*>(data_ptr); |
+ uint32_t packet_size = CFSwapInt32BigToHost(*uint32_data_ptr); |
+ // Update buffer. |
+ annexb_buffer->AppendData(kAnnexBHeaderBytes, sizeof(kAnnexBHeaderBytes)); |
+ annexb_buffer->AppendData(data_ptr + nalu_header_size, packet_size); |
+ // Update fragmentation. |
+ frag_offsets.push_back(nalu_offset + sizeof(kAnnexBHeaderBytes)); |
+ frag_lengths.push_back(packet_size); |
+ nalu_offset += sizeof(kAnnexBHeaderBytes) + packet_size; |
+ |
+ size_t bytes_written = packet_size + sizeof(kAnnexBHeaderBytes); |
+ bytes_remaining -= bytes_written; |
+ data_ptr += bytes_written; |
+ } |
+ RTC_DCHECK_EQ(bytes_remaining, (size_t)0); |
+ |
+ std::unique_ptr<webrtc::RTPFragmentationHeader> header; |
+ header.reset(new webrtc::RTPFragmentationHeader()); |
+ header->VerifyAndAllocateFragmentationHeader(frag_offsets.size()); |
+ RTC_DCHECK_EQ(frag_lengths.size(), frag_offsets.size()); |
+ for (size_t i = 0; i < frag_offsets.size(); ++i) { |
+ header->fragmentationOffset[i] = frag_offsets[i]; |
+ header->fragmentationLength[i] = frag_lengths[i]; |
+ header->fragmentationPlType[i] = 0; |
+ header->fragmentationTimeDiff[i] = 0; |
+ } |
+ *out_header = header.release(); |
+ CFRelease(contiguous_buffer); |
+ return true; |
+} |
+ |
+bool H264AnnexBBufferToCMSampleBuffer(const uint8_t* annexb_buffer, |
+ size_t annexb_buffer_size, |
+ CMVideoFormatDescriptionRef video_format, |
+ CMSampleBufferRef* out_sample_buffer) { |
+ RTC_DCHECK(annexb_buffer); |
+ RTC_DCHECK(out_sample_buffer); |
+ RTC_DCHECK(video_format); |
+ *out_sample_buffer = nullptr; |
+ |
+ AnnexBBufferReader reader(annexb_buffer, annexb_buffer_size); |
+ if (H264AnnexBBufferHasVideoFormatDescription(annexb_buffer, |
+ annexb_buffer_size)) { |
+ // Advance past the SPS and PPS. |
+ const uint8_t* data = nullptr; |
+ size_t data_len = 0; |
+ if (!reader.ReadNalu(&data, &data_len)) { |
+ LOG(LS_ERROR) << "Failed to read SPS"; |
+ return false; |
+ } |
+ if (!reader.ReadNalu(&data, &data_len)) { |
+ LOG(LS_ERROR) << "Failed to read PPS"; |
+ return false; |
+ } |
+ } |
+ |
+ // Allocate memory as a block buffer. |
+ // TODO(tkchin): figure out how to use a pool. |
+ CMBlockBufferRef block_buffer = nullptr; |
+ OSStatus status = CMBlockBufferCreateWithMemoryBlock( |
+ nullptr, nullptr, reader.BytesRemaining(), nullptr, nullptr, 0, |
+ reader.BytesRemaining(), kCMBlockBufferAssureMemoryNowFlag, |
+ &block_buffer); |
+ if (status != kCMBlockBufferNoErr) { |
+ LOG(LS_ERROR) << "Failed to create block buffer."; |
+ return false; |
+ } |
+ |
+ // Make sure block buffer is contiguous. |
+ CMBlockBufferRef contiguous_buffer = nullptr; |
+ if (!CMBlockBufferIsRangeContiguous(block_buffer, 0, 0)) { |
+ status = CMBlockBufferCreateContiguous( |
+ nullptr, block_buffer, nullptr, nullptr, 0, 0, 0, &contiguous_buffer); |
+ if (status != noErr) { |
+ LOG(LS_ERROR) << "Failed to flatten non-contiguous block buffer: " |
+ << status; |
+ CFRelease(block_buffer); |
+ return false; |
+ } |
+ } else { |
+ contiguous_buffer = block_buffer; |
+ block_buffer = nullptr; |
+ } |
+ |
+ // Get a raw pointer into allocated memory. |
+ size_t block_buffer_size = 0; |
+ char* data_ptr = nullptr; |
+ status = CMBlockBufferGetDataPointer(contiguous_buffer, 0, nullptr, |
+ &block_buffer_size, &data_ptr); |
+ if (status != kCMBlockBufferNoErr) { |
+ LOG(LS_ERROR) << "Failed to get block buffer data pointer."; |
+ CFRelease(contiguous_buffer); |
+ return false; |
+ } |
+ RTC_DCHECK(block_buffer_size == reader.BytesRemaining()); |
+ |
+ // Write Avcc NALUs into block buffer memory. |
+ AvccBufferWriter writer(reinterpret_cast<uint8_t*>(data_ptr), |
+ block_buffer_size); |
+ while (reader.BytesRemaining() > 0) { |
+ const uint8_t* nalu_data_ptr = nullptr; |
+ size_t nalu_data_size = 0; |
+ if (reader.ReadNalu(&nalu_data_ptr, &nalu_data_size)) { |
+ writer.WriteNalu(nalu_data_ptr, nalu_data_size); |
+ } |
+ } |
+ |
+ // Create sample buffer. |
+ status = CMSampleBufferCreate(nullptr, contiguous_buffer, true, nullptr, |
+ nullptr, video_format, 1, 0, nullptr, 0, |
+ nullptr, out_sample_buffer); |
+ if (status != noErr) { |
+ LOG(LS_ERROR) << "Failed to create sample buffer."; |
+ CFRelease(contiguous_buffer); |
+ return false; |
+ } |
+ CFRelease(contiguous_buffer); |
+ return true; |
+} |
+ |
+bool H264AnnexBBufferHasVideoFormatDescription(const uint8_t* annexb_buffer, |
+ size_t annexb_buffer_size) { |
+ RTC_DCHECK(annexb_buffer); |
+ RTC_DCHECK_GT(annexb_buffer_size, 4); |
+ |
+ // The buffer we receive via RTP has 00 00 00 01 start code artifically |
+ // embedded by the RTP depacketizer. Extract NALU information. |
+ // TODO(tkchin): handle potential case where sps and pps are delivered |
+ // separately. |
+ NaluType first_nalu_type = ParseNaluType(annexb_buffer[4]); |
+ bool is_first_nalu_type_sps = first_nalu_type == kSps; |
+ if (is_first_nalu_type_sps) |
+ return true; |
+ bool is_first_nalu_type_aud = first_nalu_type == kAud; |
+ // Start code + access unit delimiter + start code = 4 + 2 + 4 = 10. |
+ if (!is_first_nalu_type_aud || annexb_buffer_size <= 10u) |
+ return false; |
+ NaluType second_nalu_type = ParseNaluType(annexb_buffer[10]); |
+ bool is_second_nalu_type_sps = second_nalu_type == kSps; |
+ return is_second_nalu_type_sps; |
+} |
+ |
+CMVideoFormatDescriptionRef CreateVideoFormatDescription( |
+ const uint8_t* annexb_buffer, |
+ size_t annexb_buffer_size) { |
+ if (!H264AnnexBBufferHasVideoFormatDescription(annexb_buffer, |
+ annexb_buffer_size)) { |
+ return nullptr; |
+ } |
+ AnnexBBufferReader reader(annexb_buffer, annexb_buffer_size); |
+ CMVideoFormatDescriptionRef description = nullptr; |
+ OSStatus status = noErr; |
+ // Parse the SPS and PPS into a CMVideoFormatDescription. |
+ const uint8_t* param_set_ptrs[2] = {}; |
+ size_t param_set_sizes[2] = {}; |
+ // Skip AUD. |
+ if (ParseNaluType(annexb_buffer[4]) == kAud) { |
+ if (!reader.ReadNalu(¶m_set_ptrs[0], ¶m_set_sizes[0])) { |
+ LOG(LS_ERROR) << "Failed to read AUD"; |
+ return nullptr; |
+ } |
+ } |
+ if (!reader.ReadNalu(¶m_set_ptrs[0], ¶m_set_sizes[0])) { |
+ LOG(LS_ERROR) << "Failed to read SPS"; |
+ return nullptr; |
+ } |
+ if (!reader.ReadNalu(¶m_set_ptrs[1], ¶m_set_sizes[1])) { |
+ LOG(LS_ERROR) << "Failed to read PPS"; |
+ return nullptr; |
+ } |
+ status = CMVideoFormatDescriptionCreateFromH264ParameterSets( |
+ kCFAllocatorDefault, 2, param_set_ptrs, param_set_sizes, 4, |
+ &description); |
+ if (status != noErr) { |
+ LOG(LS_ERROR) << "Failed to create video format description."; |
+ return nullptr; |
+ } |
+ return description; |
+} |
+ |
+AnnexBBufferReader::AnnexBBufferReader(const uint8_t* annexb_buffer, |
+ size_t length) |
+ : start_(annexb_buffer), length_(length) { |
+ RTC_DCHECK(annexb_buffer); |
+ offsets_ = H264::FindNaluIndices(annexb_buffer, length); |
+ offset_ = offsets_.begin(); |
+} |
+ |
+bool AnnexBBufferReader::ReadNalu(const uint8_t** out_nalu, |
+ size_t* out_length) { |
+ RTC_DCHECK(out_nalu); |
+ RTC_DCHECK(out_length); |
+ *out_nalu = nullptr; |
+ *out_length = 0; |
+ |
+ if (offset_ == offsets_.end()) { |
+ return false; |
+ } |
+ *out_nalu = start_ + offset_->payload_start_offset; |
+ *out_length = offset_->payload_size; |
+ ++offset_; |
+ return true; |
+} |
+ |
+size_t AnnexBBufferReader::BytesRemaining() const { |
+ if (offset_ == offsets_.end()) { |
+ return 0; |
+ } |
+ return length_ - offset_->start_offset; |
+} |
+ |
+AvccBufferWriter::AvccBufferWriter(uint8_t* const avcc_buffer, size_t length) |
+ : start_(avcc_buffer), offset_(0), length_(length) { |
+ RTC_DCHECK(avcc_buffer); |
+} |
+ |
+bool AvccBufferWriter::WriteNalu(const uint8_t* data, size_t data_size) { |
+ // Check if we can write this length of data. |
+ if (data_size + kAvccHeaderByteSize > BytesRemaining()) { |
+ return false; |
+ } |
+ // Write length header, which needs to be big endian. |
+ uint32_t big_endian_length = CFSwapInt32HostToBig(data_size); |
+ memcpy(start_ + offset_, &big_endian_length, sizeof(big_endian_length)); |
+ offset_ += sizeof(big_endian_length); |
+ // Write data. |
+ memcpy(start_ + offset_, data, data_size); |
+ offset_ += data_size; |
+ return true; |
+} |
+ |
+size_t AvccBufferWriter::BytesRemaining() const { |
+ return length_ - offset_; |
+} |
+ |
+} // namespace webrtc |