Android FFmpeg系列09--抽帧与快速抽帧

object FFMpegUtils {

    interface VideoFrameArrivedInterface {
        /**
         * @param duration
         * 给定视频时长，返回待抽帧的pts arr，单位为s
         */
        fun onFetchStart(duration: Double): DoubleArray

        /**
         * 每抽帧一次回调一次
         */
        fun onProgress(frame: ByteBuffer, timestamps: Double, width: Int, height: Int, index: Int): Boolean

        /**
         * 抽帧动作结束
         */
        fun onFetchEnd()
    }

    fun getVideoFrames(path: String,
                       width: Int,
                       height: Int,
                       cb: VideoFrameArrivedInterface) {
        getVideoFramesCore(path, width, height, cb)
    }

    private external fun getVideoFramesCore(path: String,
                                            width: Int,
                                            height: Int,
                                            cb: VideoFrameArrivedInterface)
}

#ifndef FFMPEGDEMO_FFREADER_H
#define FFMPEGDEMO_FFREADER_H

#include <string>

extern "C" {
#include "libavformat/avformat.h"
#include "libavcodec/avcodec.h"
#include "libswscale/swscale.h"
#include "libavutil/imgutils.h"
}

enum TrackType {
    Track_Video,
    Track_Audio
};

/**
 * read AVPacket class
 */
class FFReader {

public:
    FFReader();
    virtual ~FFReader();

    bool init(std::string &path);

    bool selectTrack(TrackType type);

    int fetchAvPacket(AVPacket *pkt);

    bool isKeyFrame(AVPacket *pkt);

    /**
     * 获取timestamp对应的关键帧index，基于BACKWARD
     * @param timestamp: 时间单位s
     * @return
     */
    int getKeyFrameIndex(int64_t timestamp);

    double getDuration();

    /**
     * seek
     * @param timestamp: 时间单位s
     */
    void seek(int64_t timestamp);

    void flush();

    void release();

private:
    // ....略
};


#endif //FFMPEGDEMO_FFREADER_H

#ifndef FFMPEGDEMO_FFVIDEOREADER_H
#define FFMPEGDEMO_FFVIDEOREADER_H

#include "FFReader.h"

class FFVideoReader: public FFReader{

public:
    FFVideoReader(std::string &path);
    ~FFVideoReader();

    void getFrame(int64_t pts, int width, int height, uint8_t *buffer);

private:
    // ...略

};


#endif //FFMPEGDEMO_FFVIDEOREADER_H