blob: 4abb892720b268d2e20a59db83c6266fd84c25f4 [file] [log] [blame]
// Copyright 2017 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 <map>
#include <memory>
#include <vector>
#include "base/callback.h"
#include "remoting/codec/webrtc_video_encoder.h"
#include "third_party/webrtc/common_types.h"
#include "ui/gfx/geometry/size.h"
namespace webrtc {
class DesktopFrame;
} // namespace webrtc
namespace remoting {
// A container of creators of various video encoder implementations. It selects
// qualified video encoders one by one according to the codec from SDP and the
// target frame.
// Clients expect to use this class in the following way:
// 1. RegisterEncoder
// 2. SetPreferredCodec
// 3. SetDesktopFrame
// 4. CreateEncoder
// 5. If nullptr is returned, nothing we can do to recover from the failure.
// 5. Otherwise, use the encoder as long as it encodes DesktopFrames
// successfully.
// 6. If the encoder failed, go back to 3 with the failed DesktopFrame.
// Selector will return nullptr if there is no more codec supporting |profile_|.
class WebrtcVideoEncoderSelector final {
struct Profile {
gfx::Size resolution;
int frame_rate; // Always > 0
using IsProfileSupportedFunction = base::Callback<bool(const Profile&)>;
using CreateEncoderFunction =
// Creates a WebrtcVideoEncoder according to the |profile_|.
std::unique_ptr<WebrtcVideoEncoder> CreateEncoder();
// Extracts information from |frame| and sets |profile_|. If the information
// extracted from |frame| is not consistent with the values in |profile_|,
// this function also resets |last_codec_|, so next CreateEncoder() function
// call returns the first codec which supports the |frame|.
void SetDesktopFrame(const webrtc::DesktopFrame& frame);
// Sets the index of the preferred codec. The |codec| is the returned index
// from RegisterEncoder() function. This function asserts |codec| >= 0 and
// < encoders_.size().
void SetPreferredCodec(int codec);
// Registers an encoder to the selector. Returns the index of the encoder.
// Clients can use the index returned by this function to set the preferred
// codec. This class does not check the return value of |creator|, it may
// return |nullptr| even if |is_supported| returns true.
int RegisterEncoder(IsProfileSupportedFunction is_supported,
CreateEncoderFunction creator);
std::vector<std::pair<IsProfileSupportedFunction, CreateEncoderFunction>>
Profile profile_;
int preferred_codec_ = -1;
int last_codec_ = -1;
} // namespace remoting