Build AVC decoder configuration record

content/common/gpu/media/avc_config_record_builder.h

+// Copyright (c) 2012 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.
+
+#ifndef CONTENT_COMMON_GPU_MEDIA_AVC_CONFIG_RECORD_BUILDER_H_
+#define CONTENT_COMMON_GPU_MEDIA_AVC_CONFIG_RECORD_BUILDER_H_
+
+#include <vector>
+
+#include "base/memory/ref_counted.h"
+#include "base/memory/ref_counted_memory.h"
+
+namespace content {
+
+struct H264NALU;
+class H264Parser;
+
+// Utility class to build an AVC configuration record given a stream of NALUs
+// containing SPS and PPS data.
+class AVCConfigRecordBuilder {
+ public:
+  AVCConfigRecordBuilder();
+  ~AVCConfigRecordBuilder();
+
+  // Processes the given NALU. If the final AVC decoder configuration record
+  // can be built then the NALU is not consumed and the record is returned
+  // in |config_record|. Otherwise the NALU is consumed and |config_record|
+  // is not modified. Returns true on success, false on failure.
+  bool ProcessNALU(H264Parser* parser,
+                   const H264NALU& nalu,
+                   std::vector<uint8_t>* config_record);
+
+  int coded_width() const { return coded_width_; }
+  int coded_height() const { return coded_height_; }
+
+ private:
+  typedef std::vector<scoped_refptr<base::RefCountedBytes> > NALUVector;
+
+  bool ProcessSPS(H264Parser* parser, const H264NALU& nalu);
+  bool ProcessPPS(H264Parser* parser, const H264NALU& nalu);
+  std::vector<uint8_t> BuildConfigRecord();
+
+  // Copies data from |nalus| into |record_buffer|. Returns the number of bytes
+  // that were written.
+  int CopyNALUsToConfigRecord(const NALUVector& nalus, uint8_t* record_buffer);
+
+  // Data for each SPS.
+  NALUVector sps_nalus_;
+  // Data for each PPS.
+  NALUVector pps_nalus_;
+  // The video codec profile stored in the SPS.
+  int sps_profile_idc_;
+  // The constraint setx flags stored in the SPS.
+  int sps_constraint_setx_flag_;
+  // The avc level stored in the SPS.
+  int sps_level_idc_;
+  // The width of the video as enocded in the SPS.
+  uint32_t coded_width_;
+  // The height of the video as enocded in the SPS.
+  uint32_t coded_height_;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_COMMON_GPU_MEDIA_AVC_CONFIG_RECORD_BUILDER_H_