chromium/third_party/webrtc/video/buffered_frame_decryptor.h

/*
 *  Copyright (c) 2018 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#ifndef VIDEO_BUFFERED_FRAME_DECRYPTOR_H_
#define VIDEO_BUFFERED_FRAME_DECRYPTOR_H_

#include <deque>
#include <memory>

#include "api/crypto/crypto_options.h"
#include "api/crypto/frame_decryptor_interface.h"
#include "api/field_trials_view.h"
#include "modules/rtp_rtcp/source/frame_object.h"

namespace webrtc {

// This callback is provided during the construction of the
// BufferedFrameDecryptor and is called each time a frame is sucessfully
// decrypted by the buffer.
class OnDecryptedFrameCallback { … };

// This callback is called each time there is a status change in the decryption
// stream. For example going from a none state to a first decryption or going
// frome a decryptable state to a non decryptable state.
class OnDecryptionStatusChangeCallback { … };

// The BufferedFrameDecryptor is responsible for deciding when to pass
// decrypted received frames onto the OnDecryptedFrameCallback. Frames can be
// delayed when frame encryption is enabled but the key hasn't arrived yet. In
// this case we stash about 1 second of encrypted frames instead of dropping
// them to prevent re-requesting the key frame. This optimization is
// particularly important on low bandwidth networks. Note stashing is only ever
// done if we have never sucessfully decrypted a frame before. After the first
// successful decryption payloads will never be stashed.
class BufferedFrameDecryptor final { … };

}  // namespace webrtc

#endif  // VIDEO_BUFFERED_FRAME_DECRYPTOR_H_