xref: /aosp_15_r20/external/v4l2_codec2/components/include/v4l2_codec2/components/VideoEncoder.h (revision 0ec5a0ec62797f775085659156625e7f1bdb369f)
1 // Copyright 2021 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #ifndef ANDROID_V4L2_CODEC2_COMPONENTS_VIDEO_ENCODER_H
6 #define ANDROID_V4L2_CODEC2_COMPONENTS_VIDEO_ENCODER_H
7 
8 #include <stdint.h>
9 #include <memory>
10 #include <vector>
11 
12 #include <base/callback.h>
13 #include <ui/Size.h>
14 
15 #include <v4l2_codec2/common/Common.h>
16 #include <v4l2_codec2/common/VideoPixelFormat.h>
17 #include <v4l2_codec2/common/VideoTypes.h>
18 
19 namespace android {
20 
21 struct BitstreamBuffer;
22 
23 class VideoEncoder {
24 public:
25     // Number of buffers on component delays.
26     static constexpr size_t kInputBufferCount = 2;
27     static constexpr size_t kOutputBufferCount = 2;
28     static constexpr VideoPixelFormat kInputPixelFormat = VideoPixelFormat::NV12;
29 
30     // The peak bitrate in function of the target bitrate, used when the bitrate mode is VBR.
31     static constexpr uint32_t kPeakBitrateMultiplier = 2u;
32 
33     // The InputFrame class can be used to store raw video frames.
34     // Note: The InputFrame does not take ownership of the data. The file descriptor is not
35     //       duplicated and the caller is responsible for keeping the data alive until the buffer
36     //       is returned by an InputBufferDoneCB() call.
37     class InputFrame {
38     public:
39         InputFrame(std::vector<int>&& fds, const std::vector<VideoFramePlane>& planes,
40                    VideoPixelFormat pixelFormat, uint64_t index, int64_t timestamp);
41         ~InputFrame() = default;
42 
fds()43         const std::vector<int>& fds() const { return mFds; }
planes()44         const std::vector<VideoFramePlane>& planes() const { return mPlanes; }
pixelFormat()45         VideoPixelFormat pixelFormat() const { return mPixelFormat; }
index()46         uint64_t index() const { return mIndex; }
timestamp()47         int64_t timestamp() const { return mTimestamp; }
48 
49     private:
50         const std::vector<int> mFds;
51         std::vector<VideoFramePlane> mPlanes;
52         VideoPixelFormat mPixelFormat;
53         uint64_t mIndex = 0;
54         int64_t mTimestamp = 0;
55     };
56 
57     using FetchOutputBufferCB =
58             ::base::RepeatingCallback<void(uint32_t, std::unique_ptr<BitstreamBuffer>* buffer)>;
59     // TODO(dstaessens): Change callbacks to OnceCallback provided when requesting encode/drain.
60     using InputBufferDoneCB = ::base::RepeatingCallback<void(uint64_t)>;
61     using OutputBufferDoneCB = ::base::RepeatingCallback<void(
62             size_t, int64_t, bool, std::unique_ptr<BitstreamBuffer> buffer)>;
63     using DrainDoneCB = ::base::RepeatingCallback<void(bool)>;
64     using ErrorCB = ::base::RepeatingCallback<void()>;
65 
66     virtual ~VideoEncoder() = default;
67 
68     // Encode the frame, |InputBufferDoneCB| and |OutputBufferDoneCB| will be called when done.
69     virtual bool encode(std::unique_ptr<InputFrame> buffer) = 0;
70     // Drain the encoder, |mDrainDoneCb| will be called when done.
71     virtual void drain() = 0;
72     // Flush the encoder, pending drain operations will be aborted.
73     virtual void flush() = 0;
74 
75     // Set the target bitrate to the specified value, will affect all non-processed frames.
76     virtual bool setBitrate(uint32_t bitrate) = 0;
77     // Set the peak bitrate to the specified value. The peak bitrate must be larger or equal to the
78     // target bitrate and is ignored if the bitrate mode is constant.
79     virtual bool setPeakBitrate(uint32_t peakBitrate) = 0;
80 
81     // Set the framerate to the specified value, will affect all non-processed frames.
82     virtual bool setFramerate(uint32_t framerate) = 0;
83     // Request the next frame encoded to be a key frame, will affect the next non-processed frame.
84     virtual void requestKeyframe() = 0;
85 
86     virtual VideoPixelFormat inputFormat() const = 0;
87     virtual const ui::Size& visibleSize() const = 0;
88     virtual const ui::Size& codedSize() const = 0;
89 };
90 
91 }  // namespace android
92 
93 #endif  // ANDROID_V4L2_CODEC2_COMPONENTS_VIDEO_ENCODER_H
94