1 // Copyright (c) 2011 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 // Note: ported from Chromium commit head: 39a7f93 5 6 #ifndef MEDIA_BASE_BITSTREAM_BUFFER_H_ 7 #define MEDIA_BASE_BITSTREAM_BUFFER_H_ 8 9 #include <stddef.h> 10 #include <stdint.h> 11 12 #include "base/macros.h" 13 #include "base/memory/shared_memory.h" 14 #include "base/time/time.h" 15 16 namespace media { 17 18 // Indicates an invalid or missing timestamp. 19 constexpr base::TimeDelta kNoTimestamp = 20 base::TimeDelta::FromMicroseconds(std::numeric_limits<int64_t>::min()); 21 22 // Class for passing bitstream buffers around. Does not take ownership of the 23 // data. This is the media-namespace equivalent of PP_VideoBitstreamBuffer_Dev. 24 class BitstreamBuffer { 25 public: 26 BitstreamBuffer(); 27 28 // Constructs a new BitstreamBuffer. The content of the bitstream is located 29 // at |offset| bytes away from the start of the shared memory and the payload 30 // is |size| bytes. When not provided, the default value for |offset| is 0. 31 // |presentation_timestamp| is when the decoded frame should be displayed. 32 // When not provided, |presentation_timestamp| will be 33 // |media::kNoTimestamp|. 34 BitstreamBuffer(int32_t id, 35 base::SharedMemoryHandle handle, 36 size_t size, 37 off_t offset = 0, 38 base::TimeDelta presentation_timestamp = kNoTimestamp); 39 40 BitstreamBuffer(const BitstreamBuffer& other); 41 42 ~BitstreamBuffer(); 43 44 int32_t id() const { return id_; } 45 base::SharedMemoryHandle handle() const { return handle_; } 46 47 // The number of bytes of the actual bitstream data. It is the size of the 48 // content instead of the whole shared memory. 49 size_t size() const { return size_; } 50 51 // The offset to the start of actual bitstream data in the shared memory. 52 off_t offset() const { return offset_; } 53 54 // The timestamp is only valid if it's not equal to |media::kNoTimestamp|. 55 base::TimeDelta presentation_timestamp() const { 56 return presentation_timestamp_; 57 } 58 59 void set_handle(const base::SharedMemoryHandle& handle) { handle_ = handle; } 60 61 private: 62 int32_t id_; 63 base::SharedMemoryHandle handle_; 64 size_t size_; 65 off_t offset_; 66 67 // This is only set when necessary. For example, AndroidVideoDecodeAccelerator 68 // needs the timestamp because the underlying decoder may require it to 69 // determine the output order. 70 base::TimeDelta presentation_timestamp_; 71 72 // Allow compiler-generated copy & assign constructors. 73 }; 74 75 } // namespace media 76 77 #endif // MEDIA_BASE_BITSTREAM_BUFFER_H_ 78
