blob: 42ac1cb27fd18a6f05a2677097709646bf075f15 [file] [log] [blame]
// 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.
#include <stdint.h>
#include <memory>
#include <vector>
#include "base/memory/scoped_refptr.h"
#include "base/memory/weak_ptr.h"
#include "base/optional.h"
#include "base/unguessable_token.h"
#include "media/base/bitstream_buffer.h"
#include "media/base/cdm_context.h"
#include "media/base/decoder_buffer.h"
#include "media/base/encryption_scheme.h"
#include "media/base/overlay_info.h"
#include "media/base/video_decoder_config.h"
#include "media/video/picture.h"
#include "ui/gfx/color_space.h"
#include "ui/gfx/geometry/size.h"
#include "ui/gfx/gpu_memory_buffer.h"
typedef unsigned int GLenum;
namespace base {
class SingleThreadTaskRunner;
namespace media {
// Video decoder interface.
// This interface is extended by the various components that ultimately
// implement the backend of PPB_VideoDecoder_Dev.
class MEDIA_EXPORT VideoDecodeAccelerator {
// Specification of a decoding profile supported by an decoder.
// |max_resolution| and |min_resolution| are inclusive.
struct MEDIA_EXPORT SupportedProfile {
VideoCodecProfile profile;
gfx::Size max_resolution;
gfx::Size min_resolution;
bool encrypted_only;
using SupportedProfiles = std::vector<SupportedProfile>;
struct MEDIA_EXPORT Capabilities {
Capabilities(const Capabilities& other);
std::string AsHumanReadableString() const;
// Flags that can be associated with a VDA.
enum Flags {
// Normally, the VDA is required to be able to provide all PictureBuffers
// to the client via PictureReady(), even if the client does not return
// any of them via ReusePictureBuffer(). The client is only required to
// return PictureBuffers when it holds all of them, if it wants to get
// more decoded output. See VideoDecoder::CanReadWithoutStalling for
// more context.
// If this flag is set, then the VDA does not make this guarantee. The
// client must return PictureBuffers to be sure that new frames will be
// provided via PictureReady.
// Whether the VDA supports being configured with an output surface for
// it to render frames to. For example, SurfaceViews on Android.
// If set, the VDA will use deferred initialization if the config
// indicates that the client supports it as well. Refer to
// NotifyInitializationComplete for more details.
// If set, video frames will have COPY_REQUIRED flag which will cause
// an extra texture copy during composition.
// Whether the VDA supports encrypted streams or not.
// If set the decoder does not require a restart in order to switch to
// using an external output surface.
SupportedProfiles supported_profiles;
uint32_t flags;
// Enumeration of potential errors generated by the API.
// Note: Keep these in sync with PP_VideoDecodeError_Dev. Also do not
// rearrange, reuse or remove values as they are used for gathering UMA
// statistics.
enum Error {
// An operation was attempted during an incompatible decoder state.
// Invalid argument was passed to an API method.
// Encoded input is unreadable.
// A failure occurred at the browser layer or one of its dependencies.
// Examples of such failures include GPU hardware failures, GPU driver
// failures, GPU library failures, browser programming errors, and so on.
// Largest used enum. This should be adjusted when new errors are added.
// Config structure contains parameters required for the VDA initialization.
struct MEDIA_EXPORT Config {
// Specifies the allocation and handling mode for output PictureBuffers.
// When set to ALLOCATE, the VDA is expected to allocate backing memory
// for PictureBuffers at the time of AssignPictureBuffers() call.
// When set to IMPORT, the VDA will not allocate, but after receiving
// AssignPictureBuffers() call, it will expect a call to
// ImportBufferForPicture() for each PictureBuffer before use.
enum class OutputMode {
Config(const Config& config);
explicit Config(VideoCodecProfile profile);
std::string AsHumanReadableString() const;
bool is_encrypted() const { return encryption_scheme.is_encrypted(); }
// The video codec and profile.
VideoCodecProfile profile = VIDEO_CODEC_PROFILE_UNKNOWN;
// Whether the stream is encrypted, and, if so, the scheme used.
EncryptionScheme encryption_scheme;
// The CDM that the VDA should use to decode encrypted streams. Must be
// set to a valid ID if |is_encrypted|.
int cdm_id = CdmContext::kInvalidCdmId;
// Whether the client supports deferred initialization.
bool is_deferred_initialization_allowed = false;
// Optional overlay info available at startup, rather than waiting for the
// VDA to receive a callback.
OverlayInfo overlay_info;
// Coded size of the video frame hint, subject to change.
gfx::Size initial_expected_coded_size = gfx::Size(320, 240);
OutputMode output_mode = OutputMode::ALLOCATE;
// The list of picture buffer formats that the client knows how to use. An
// empty list means any format is supported.
std::vector<VideoPixelFormat> supported_output_formats;
// The H264 SPS and PPS configuration data. Not all clients populate these
// fields, so they should be parsed from the bitstream instead, if required.
// Each SPS and PPS is prefixed with the Annex B framing bytes: 0, 0, 0, 1.
std::vector<uint8_t> sps;
std::vector<uint8_t> pps;
// Color space specified by the container.
VideoColorSpace container_color_space;
// Target color space.
// Used as a hint to the decoder. Outputting VideoFrames in this color space
// may avoid extra conversion steps.
gfx::ColorSpace target_color_space;
// HDR metadata specified by the container.
base::Optional<HDRMetadata> hdr_metadata;
// Interface for collaborating with picture interface to provide memory for
// output picture and blitting them. These callbacks will not be made unless
// Initialize() has returned successfully.
// This interface is extended by the various layers that relay messages back
// to the plugin, through the PPP_VideoDecoder_Dev interface the plugin
// implements.
class MEDIA_EXPORT Client {
// Notify the client that deferred initialization has completed successfully
// or not. This is required if and only if deferred initialization is
// supported by the VDA (see Capabilities), and it is supported by the
// client (see Config::is_deferred_initialization_allowed), and the initial
// call to VDA::Initialize returns true.
// The default implementation is a NOTREACHED, since deferred initialization
// is not supported by default.
virtual void NotifyInitializationComplete(bool success);
// Callback to tell client how many and what size of buffers to provide.
// Note that the actual count provided through AssignPictureBuffers() can be
// larger than the value requested.
// |format| indicates what format the decoded frames will be produced in
// by the VDA, or PIXEL_FORMAT_UNKNOWN if the underlying platform handles
// this transparently.
virtual void ProvidePictureBuffers(uint32_t requested_num_of_buffers,
VideoPixelFormat format,
uint32_t textures_per_buffer,
const gfx::Size& dimensions,
uint32_t texture_target) = 0;
// Callback to dismiss picture buffer that was assigned earlier.
virtual void DismissPictureBuffer(int32_t picture_buffer_id) = 0;
// Callback to deliver decoded pictures ready to be displayed.
// Note: the decoded pictures might be sent to the client more than once.
// The client should call ReusePictureBuffer() once for each PictureReady().
// For example, VDA calls Client::PictureReady() twice for a picture buffer.
// Then the client should also call VDA::ReusePictureBuffer() twice.
// Until that, VDA cannot reuse the picture buffer.
virtual void PictureReady(const Picture& picture) = 0;
// Callback to notify that decoded has decoded the end of the current
// bitstream buffer.
virtual void NotifyEndOfBitstreamBuffer(int32_t bitstream_buffer_id) = 0;
// Flush completion callback.
virtual void NotifyFlushDone() = 0;
// Reset completion callback.
virtual void NotifyResetDone() = 0;
// Callback to notify about decoding errors. Note that errors in
// Initialize() will not be reported here, but will instead be indicated by
// a false return value there.
virtual void NotifyError(Error error) = 0;
virtual ~Client() {}
// Video decoder functions.
// Initializes the video decoder with specific configuration. Called once per
// decoder construction. This call is synchronous and returns true iff
// initialization is successful, unless deferred initialization is used.
// By default, deferred initialization is not used. However, if Config::
// is_deferred_initialization_allowed is set by the client, and if
// Capabilities::Flags::SUPPORTS_DEFERRED_INITIALIZATION is set by the VDA,
// and if VDA::Initialize returns true, then the client can expect a call to
// NotifyInitializationComplete with the actual success / failure of
// initialization. Note that a return value of false from VDA::Initialize
// indicates that initialization definitely failed, and no callback is needed.
// For encrypted video, only deferred initialization is supported and |config|
// must contain a valid |cdm_id|.
// Parameters:
// |config| contains the initialization parameters.
// |client| is the client of this video decoder. Does not take ownership of
// |client| which must be valid until Destroy() is called.
virtual bool Initialize(const Config& config, Client* client) = 0;
// Decodes given bitstream buffer that contains at most one frame. Once
// decoder is done with processing |bitstream_buffer| it will call
// NotifyEndOfBitstreamBuffer() with the bitstream buffer id.
// Parameters:
// |bitstream_buffer| is the input bitstream that is sent for decoding.
virtual void Decode(const BitstreamBuffer& bitstream_buffer) = 0;
// Decodes given decoder buffer that contains at most one frame. Once
// decoder is done with processing |buffer| it will call
// NotifyEndOfBitstreamBuffer() with the bitstream id.
// Parameters:
// |buffer| is the input buffer that is sent for decoding.
// |bitstream_id| identifies the buffer for PictureReady() and
// NotifyEndOfBitstreamBuffer()
virtual void Decode(scoped_refptr<DecoderBuffer> buffer,
int32_t bitstream_id);
// Assigns a set of texture-backed picture buffers to the video decoder.
// Ownership of each picture buffer remains with the client, but the client
// is not allowed to deallocate the buffer before the DismissPictureBuffer
// callback has been initiated for a given buffer.
// Parameters:
// |buffers| contains the allocated picture buffers for the output. Note
// that the count of buffers may be larger than the count requested through
// the call to Client::ProvidePictureBuffers().
virtual void AssignPictureBuffers(
const std::vector<PictureBuffer>& buffers) = 0;
// Imports |gpu_memory_buffer_handle|, pointing to a buffer in |pixel_format|,
// as backing memory for picture buffer associated with |picture_buffer_id|.
// This can only be be used if the VDA has been Initialize()d with
// config.output_mode = IMPORT, and should be preceded by a call to
// AssignPictureBuffers() to set up the number of PictureBuffers and their
// details.
// The |pixel_format| used here may be different from the |pixel_format|
// required in ProvidePictureBuffers(). If the buffer cannot be imported an
// error should be notified via NotifyError().
// After this call, the VDA becomes the owner of the GpuMemoryBufferHandle,
// and is responsible for closing it after use, also on import failure.
virtual void ImportBufferForPicture(
int32_t picture_buffer_id,
VideoPixelFormat pixel_format,
const gfx::GpuMemoryBufferHandle& gpu_memory_buffer_handle);
// Sends picture buffers to be reused by the decoder. This needs to be called
// for each buffer that has been processed so that decoder may know onto which
// picture buffers it can write the output to.
// Note: the decoded pictures might be sent to the client more than once.
// The client should call ReusePictureBuffer() once for each PictureReady().
// For example, VDA calls Client::PictureReady() twice for a picture buffer.
// Then the client should also call VDA::ReusePictureBuffer() twice.
// Until that, VDA can really reuse the picture buffer.
// Parameters:
// |picture_buffer_id| id of the picture buffer that is to be reused.
virtual void ReusePictureBuffer(int32_t picture_buffer_id) = 0;
// Flushes the decoder: all pending inputs will be decoded and pictures handed
// back to the client, followed by NotifyFlushDone() being called on the
// client. Can be used to implement "end of stream" notification.
virtual void Flush() = 0;
// Resets the decoder: all pending inputs are dropped immediately and the
// decoder returned to a state ready for further Decode()s, followed by
// NotifyResetDone() being called on the client. Can be used to implement
// "seek". After Flush is called, it is OK to call Reset before receiving
// NotifyFlushDone() and VDA should cancel the flush. Note NotifyFlushDone()
// may be on the way to the client. If client gets NotifyFlushDone(), it
// should be before NotifyResetDone().
virtual void Reset() = 0;
// An optional graphics surface that the VDA should render to. For setting
// an output SurfaceView on Android. Passing |kNoSurfaceID| will clear any
// previously set surface in favor of an internally generated texture.
// |routing_token| is an optional AndroidOverlay routing token. At most one
// should be non-empty.
virtual void SetOverlayInfo(const OverlayInfo& overlay_info);
// Destroys the decoder: all pending inputs are dropped immediately and the
// component is freed. This call may asynchornously free system resources,
// but its client-visible effects are synchronous. After this method returns
// no more callbacks will be made on the client. Deletes |this|
// unconditionally, so make sure to drop all pointers to it!
virtual void Destroy() = 0;
// A decode "task" is a sequence that includes a Decode() call from Client,
// as well as corresponding callbacks to return the input BitstreamBuffer
// after use, and the resulting output Picture(s).
// If the Client can support running these three calls on a separate thread,
// it may call this method to try to set up the VDA implementation to do so.
// If the VDA can support this as well, return true, otherwise return false.
// If true is returned, the client may submit each Decode() call (but no other
// calls) on |decode_task_runner|, and should then expect that
// NotifyEndOfBitstreamBuffer() and PictureReady() callbacks may come on
// |decode_task_runner| as well, called on |decode_client|, instead of client
// provided to Initialize().
// This method may be called at any time.
// NOTE 1: some callbacks may still have to come on the main thread and the
// Client should handle both callbacks coming on main and |decode_task_runner|
// thread.
// NOTE 2: VDA implementations of Decode() must return as soon as possible and
// never block, as |decode_task_runner| may be a latency critical thread
// (such as the GPU IO thread).
// One application of this is offloading the GPU Child thread. In general,
// calls to VDA in GPU process have to be done on the GPU Child thread, as
// they may require GL context to be current. However, some VDAs may be able
// to run decode operations without GL context, which helps reduce latency and
// offloads the GPU Child thread.
virtual bool TryToSetupDecodeOnSeparateThread(
const base::WeakPtr<Client>& decode_client,
const scoped_refptr<base::SingleThreadTaskRunner>& decode_task_runner);
// Windows creates a BGRA texture.
// TODO(dshwang): after moving to D3D11, remove this.
virtual GLenum GetSurfaceInternalFormat() const;
// Do not delete directly; use Destroy() or own it with a scoped_ptr, which
// will Destroy() it properly by default.
virtual ~VideoDecodeAccelerator();
} // namespace media
namespace std {
// Specialize std::default_delete so that
// std::unique_ptr<VideoDecodeAccelerator> uses "Destroy()" instead of trying to
// use the destructor.
template <>
struct MEDIA_EXPORT default_delete<media::VideoDecodeAccelerator> {
void operator()(media::VideoDecodeAccelerator* vda) const;
} // namespace std