blob: 343ca0700e2bf9d68266f5d75a0f2b9f2dd253ed [file] [log] [blame]
// Copyright (c) 2011 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.
#include <stddef.h>
#include <stdint.h>
#include "base/macros.h"
#include "base/memory/platform_shared_memory_region.h"
#include "base/memory/scoped_refptr.h"
#include "base/time/time.h"
#include "media/base/decoder_buffer.h"
#include "media/base/decrypt_config.h"
#include "media/base/media_export.h"
#include "media/base/timestamp_constants.h"
namespace IPC {
template <class P>
struct ParamTraits;
namespace media {
// Class for passing bitstream buffers around. Does not take ownership of the
// data. This is the media-namespace equivalent of PP_VideoBitstreamBuffer_Dev.
class MEDIA_EXPORT BitstreamBuffer {
// Constructs a new BitstreamBuffer. The content of the bitstream is located
// at |offset| bytes away from the start of the shared memory and the payload
// is |size| bytes. When not provided, the default value for |offset| is 0.
// |presentation_timestamp| is when the decoded frame should be displayed.
// When not provided, |presentation_timestamp| will be
// |media::kNoTimestamp|.
BitstreamBuffer(int32_t id,
base::subtle::PlatformSharedMemoryRegion region,
size_t size,
off_t offset = 0,
base::TimeDelta presentation_timestamp = kNoTimestamp);
// As above, but creates by duplicating a SharedMemoryHandle.
// TODO( remove once legacy shared memory has been
// converted.
BitstreamBuffer(int32_t id,
base::SharedMemoryHandle handle,
bool read_only,
size_t size,
off_t offset = 0,
base::TimeDelta presentation_timestamp = kNoTimestamp);
// Move operations are allowed.
BitstreamBuffer& operator=(BitstreamBuffer&&);
// Produce an equivalent DecoderBuffer. This consumes region(), even if
// nullptr is returned.
// This method is only intended to be used by VDAs that are being converted to
// use DecoderBuffer.
// TODO(sandersd): Remove once all VDAs are converted.
scoped_refptr<DecoderBuffer> ToDecoderBuffer();
// TODO( As this is only used by Android, include
// EncryptionMode and optional EncryptionPattern when updating for Android.
void SetDecryptionSettings(const std::string& key_id,
const std::string& iv,
const std::vector<SubsampleEntry>& subsamples);
// Taking the region invalides the one in this BitstreamBuffer.
base::subtle::PlatformSharedMemoryRegion TakeRegion() {
return std::move(region_);
// If a region needs to be taken from a const BitstreamBuffer, it must be
// duplicated. This function makes that explicit.
// TODO( this is probably only needed by legacy IPC, and can
// be removed once that is converted to the new shared memory API.
base::subtle::PlatformSharedMemoryRegion DuplicateRegion() const {
return region_.Duplicate();
const base::subtle::PlatformSharedMemoryRegion& region() const {
return region_;
int32_t id() const { return id_; }
// The number of bytes of the actual bitstream data. It is the size of the
// content instead of the whole shared memory.
size_t size() const { return size_; }
// The offset to the start of actual bitstream data in the shared memory.
off_t offset() const { return offset_; }
// The timestamp is only valid if it's not equal to |media::kNoTimestamp|.
base::TimeDelta presentation_timestamp() const {
return presentation_timestamp_;
void set_region(base::subtle::PlatformSharedMemoryRegion region) {
region_ = std::move(region);
// The following methods come from SetDecryptionSettings().
const std::string& key_id() const { return key_id_; }
const std::string& iv() const { return iv_; }
const std::vector<SubsampleEntry>& subsamples() const { return subsamples_; }
int32_t id_;
base::subtle::PlatformSharedMemoryRegion region_;
size_t size_;
off_t offset_;
// Note: Not set by all clients.
base::TimeDelta presentation_timestamp_;
// Note that BitstreamBuffer uses the settings in Audio/VideoDecoderConfig
// to determine the encryption mode and pattern (if required by the encryption
// scheme).
// TODO(timav): Try to DISALLOW_COPY_AND_ASSIGN and include these params as
// std::unique_ptr<DecryptConfig> or explain why copy & assign is needed.
std::string key_id_; // key ID.
std::string iv_; // initialization vector
std::vector<SubsampleEntry> subsamples_; // clear/cypher sizes
friend struct IPC::ParamTraits<media::BitstreamBuffer>;
} // namespace media