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media / cast / encoding / video_encoder.h [blame]
// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef MEDIA_CAST_ENCODING_VIDEO_ENCODER_H_
#define MEDIA_CAST_ENCODING_VIDEO_ENCODER_H_
#include <memory>
#include "base/functional/callback.h"
#include "base/memory/scoped_refptr.h"
#include "base/time/time.h"
#include "media/base/video_frame.h"
#include "media/cast/cast_callbacks.h"
#include "media/cast/cast_config.h"
#include "media/cast/cast_environment.h"
namespace media {
class VideoEncoderMetricsProvider;
namespace cast {
struct SenderEncodedFrame;
// This interface encapsulates logic for encoding video frames, and abstracts
// out complexities related to specific encoder implementations.
//
// NOTE: All public methods must be called from the MAIN CastEnvironment thread.
class VideoEncoder {
public:
// Callback used to deliver an encoded frame on the MAIN thread.
using FrameEncodedCallback =
base::RepeatingCallback<void(std::unique_ptr<SenderEncodedFrame>)>;
// Creates a VideoEncoder instance from the given `video_config` and based on
// the current platform's hardware/library support; or null if no
// implementation will suffice. The instance will run `status_change_cb` at
// some point in the future to indicate initialization success/failure.
//
// All VideoEncoder instances returned by this function support encoding
// sequences of differently-size VideoFrames.
static std::unique_ptr<VideoEncoder> Create(
const scoped_refptr<CastEnvironment>& cast_environment,
const FrameSenderConfig& video_config,
std::unique_ptr<VideoEncoderMetricsProvider> metrics_provider,
StatusChangeCallback status_change_cb,
FrameEncodedCallback output_cb,
const CreateVideoEncodeAcceleratorCallback& create_vea_cb);
virtual ~VideoEncoder() {}
// If true is returned, the Encoder has accepted the request and will process
// it asynchronously, running `output_cb_` on the MAIN CastEnvironment thread
// with the result. If false is returned, the video frame has been dropped and
// the `output_cb_` will not be called. This may be due to the encoder being
// overloaded, in which case the calling class can just try again. More
// serious errors will be reported through the `status_change_cb_`.
[[nodiscard]] virtual bool EncodeVideoFrame(
scoped_refptr<media::VideoFrame> video_frame,
base::TimeTicks reference_time) = 0;
// Inform the encoder about the new target bit rate.
virtual void SetBitRate(int new_bit_rate) = 0;
// Inform the encoder to encode the next frame as a key frame.
virtual void GenerateKeyFrame() = 0;
};
} // namespace cast
} // namespace media
#endif // MEDIA_CAST_ENCODING_VIDEO_ENCODER_H_