FFmpeg提取视频参数，以及剪辑视频，拼接视频，合并视频，抽帧等

FFmpeg提取视频参数，以及剪辑视频，拼接视频，合并视频，抽帧等

  • 视频封面图获取
    • 视频

视频封面图获取


#ifndef _BUFFER_CONTAINER_H_
#define _BUFFER_CONTAINER_H_
#include <Memory>template <typename T>
class BufferContainer
{
public:/*** @brief Construct a new Buffer Container object 构造函数赋值拷贝内存** @param t1* @param length*/BufferContainer(){m_buffer = nullptr;m_length = 0;}/*** @brief Construct a new Buffer Container object 构造函数赋值拷贝内存** @param t1* @param length*/BufferContainer(const T &t1, int length){if (t1 && length > 0){m_buffer = new T[length];memset(m_buffer,0,length* sizeof(T));m_length = length;memcpy(m_buffer, &t1, length * sizeof(T));}}void setData(T*pData,int length){if(pData&&m_buffer){delete [] m_buffer;m_buffer=nullptr;}if(length>0&&m_length>0){m_length=0;}m_buffer=new T[length];memset(m_buffer,0,length* sizeof(T));m_length = length;memcpy(m_buffer, pData, length * sizeof(T));}/*** @brief Construct a new Buffer Container object 深拷贝构造函数** @param other*/BufferContainer(const BufferContainer &other){if (other.m_buffer && other.m_length > 0){m_buffer = new T[other.m_length];memset(m_buffer,0,other.m_length* sizeof(T));m_length = other.m_length;memcpy(m_buffer, other.m_buffer, other.m_length * sizeof(T));}}/*** @brief Destroy the Buffer Container object  析构函数**/~BufferContainer(){if (m_buffer){delete[] m_buffer;m_buffer = nullptr;m_length = 0;}}/*** @brief  赋值操作符重载** @param other* @return BufferContainer&*/BufferContainer &operator=(const BufferContainer &other){
//        if (this != other){delete[] m_buffer;m_buffer = nullptr;m_length = 0;if (other.m_buffer){m_buffer = new T[other.m_length];memset(m_buffer,0,other.m_length* sizeof(T));m_length = other.m_length;memcpy(m_buffer, other.m_buffer, sizeof(T) * other.m_length);}}return *this;}/*** @brief 返回数据指针** @return T**/T *data(){return m_buffer;}/*** @brief 返回数据长度** @return int*/int length(){return m_length;}private:T *m_buffer = nullptr;int m_length = 0;
};#endif //_BUFFER_CONTAINER_H_

BufferContainer<unsigned char> VideoEditerBase::thumbnail(const std::string& filePath)
{av_register_all();BufferContainer<unsigned char> result;AVFormatContext* fmtContext = nullptr;if (avformat_open_input(&fmtContext, filePath.c_str(), nullptr, nullptr) < 0) {return result;}if (avformat_find_stream_info(fmtContext, nullptr) < 0) {avformat_close_input(&fmtContext);return result;}int nStreamIndex = -1;AVCodecParameters* codecParameters = nullptr;for (int i = 0; i < fmtContext->nb_streams; i++) {if (fmtContext->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {nStreamIndex = i;codecParameters = fmtContext->streams[i]->codecpar;break;}}if (nStreamIndex == -1) {avformat_close_input(&fmtContext);return result;}AVCodec* codec = avcodec_find_decoder(codecParameters->codec_id);if (!codec) {avformat_close_input(&fmtContext);return result;}AVCodecContext* codecContext = avcodec_alloc_context3(codec);if (!codecContext) {// ���������������ʧ��avformat_close_input(&fmtContext);return result;}if (avcodec_parameters_to_context(codecContext, codecParameters) < 0) {// ���ƽ�����������������������ʧ��avcodec_free_context(&codecContext);avformat_close_input(&fmtContext);return result;}if (avcodec_open2(codecContext, codec, nullptr) < 0) {// �򿪽�����ʧ��avcodec_free_context(&codecContext);avformat_close_input(&fmtContext);return result;}AVPacket packet;av_init_packet(&packet);packet.data = nullptr;packet.size = 0;//    bool getFlag=true;int frameFinished = 0;AVFrame* frame = av_frame_alloc();while (av_read_frame(fmtContext, &packet) >= 0) {if (packet.stream_index != nStreamIndex) {continue;}int ret = avcodec_decode_video2(codecContext, frame, &frameFinished, &packet);if (!frameFinished) {continue;}if (frame) {int ret = avcodec_send_packet(codecContext, &packet);if (ret >= 0) {ret = avcodec_receive_frame(codecContext, frame);if (ret >= 0) {// ����һ֡����Ϊ����ͼ��if (frame->key_frame) {AVFrame* rgbFrame = av_frame_alloc();if (rgbFrame) {rgbFrame->format = AV_PIX_FMT_RGB24;rgbFrame->width = frame->width;rgbFrame->height = frame->height;int bufferSize = av_image_get_buffer_size(AV_PIX_FMT_RGB24, frame->width, frame->height, 1);uint8_t* buffer = new uint8_t[bufferSize];av_image_fill_arrays(rgbFrame->data, rgbFrame->linesize, buffer, AV_PIX_FMT_RGB24, frame->width, frame->height, 1);SwsContext* swsContext = sws_getContext(frame->width, frame->height, codecContext->pix_fmt,frame->width, frame->height, AV_PIX_FMT_RGB24, SWS_BICUBIC, nullptr, nullptr, nullptr);if (swsContext) {sws_scale(swsContext, frame->data, frame->linesize, 0, frame->height, rgbFrame->data, rgbFrame->linesize);sws_freeContext(swsContext);// �������ͼ���ļ�int outputBufferSize = rgbFrame->width * rgbFrame->height * 3;unsigned char* outputBuffer = new unsigned char[outputBufferSize];for (int i = 0; i < rgbFrame->height; i++) {memcpy(outputBuffer + i * rgbFrame->width * 3, rgbFrame->data[0] + i * rgbFrame->linesize[0], rgbFrame->width * 3);}//                                static int index=0;//                                QImage(outputBuffer, rgbFrame->width, rgbFrame->height, QImage::Format_RGB888).copy().save(QString("E:/workspace/build-VideoCodec-Desktop_Qt_5_7_1_MSVC2015_64bit-Debug/debug/%1.jpg").arg(index++));result.setData(outputBuffer, outputBufferSize);if (outputBuffer) {delete[] outputBuffer;outputBuffer = nullptr;}}if (buffer) {delete[] buffer;buffer = nullptr;}av_frame_free(&rgbFrame);}}}}}av_packet_unref(&packet);break;}av_frame_free(&frame);avcodec_free_context(&codecContext);avformat_close_input(&fmtContext);return result;}

视频

#include "videoeditermp4.h"
#include <QDebug>
extern "C" {
#include "libavformat/avformat.h"
#include "libavcodec/avcodec.h"
#include "libavutil/imgutils.h"
#include "libavutil/opt.h"
#include "libswresample/swresample.h"
#include "libswscale/swscale.h"
}
VideoEditerMp4::VideoEditerMp4()
{}
VideoEditerMp4::~VideoEditerMp4() {stop();
}
void VideoEditerMp4::startClip(std::string input, std::string output, int64_t st, int64_t et)
{if(!m_vecInputPaths.empty()){m_vecInputPaths.clear();}//    stop();m_vecInputPaths.push_back(input);m_outputPath = output;m_startTime = st;m_endTime = et;m_pThread = new std::thread(&VideoEditerMp4::runClip, this);m_pThread->detach();
}void VideoEditerMp4::startMerge(std::vector<std::string>inputs, std::string output)
{if (!m_vecInputPaths.empty()) {m_vecInputPaths.clear();}//    stop();m_vecInputPaths=inputs;m_outputPath = output;m_pThread = new std::thread(&VideoEditerMp4::runMerge, this);m_pThread->detach();
}void VideoEditerMp4::runClip()
{stateCallBack(RUNNING);if (m_vecInputPaths.empty() || m_outputPath.empty()) {stateCallBack(FAIL);return;}AVFormatContext* fmtContext = avformat_alloc_context();if (avformat_open_input(&fmtContext,m_vecInputPaths.front().c_str() , nullptr, nullptr) < 0) {//fprintf(stderr, "�޷��򿪵�һ�������ļ�\n");stateCallBack(FAIL);return ;}if (avformat_find_stream_info(fmtContext, nullptr) < 0) {//fprintf(stderr, "�޷��ҵ���һ�������ļ�������Ϣ\n");avformat_close_input(&fmtContext);stateCallBack(FAIL);return ;}int videoStreamIndex = -1;for (int i = 0; i < fmtContext->nb_streams; i++) {if (fmtContext->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {videoStreamIndex = i;break;}}int audioStreamIndex = -1;for (int i = 0; i < fmtContext->nb_streams; i++) {if (fmtContext->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {audioStreamIndex = i;break;}}AVFormatContext* output_format_ctx = nullptr;if (avformat_alloc_output_context2(&output_format_ctx, nullptr, nullptr, m_outputPath.c_str())){avformat_close_input(&fmtContext);stateCallBack(FAIL);return;}// ���������ļ�����for (int i = 0; i < fmtContext->nb_streams; i++) {AVStream* stream = avformat_new_stream(output_format_ctx, nullptr);if (!stream) {avformat_close_input(&fmtContext);avformat_close_input(&output_format_ctx);stateCallBack(FAIL);return;}//        stream->time_base=fmtContext->streams[videoStreamIndex]->time_base;//        stream->duration=(m_endTime-m_startTime);if (avcodec_copy_context(stream->codec, fmtContext->streams[i]->codec)<0) {avformat_close_input(&fmtContext);avformat_close_input(&output_format_ctx);stateCallBack(FAIL);return;}if (avcodec_parameters_copy(stream->codecpar, fmtContext->streams[i]->codecpar) < 0) {avformat_close_input(&fmtContext);avformat_close_input(&output_format_ctx);stateCallBack(FAIL);return;}}// ������ļ�if (!(output_format_ctx->oformat->flags & AVFMT_NOFILE)) {if (avio_open(&output_format_ctx->pb, m_outputPath.c_str(), AVIO_FLAG_WRITE) < 0) {//            fprintf(stderr, "�޷�������ļ�\n");avformat_close_input(&fmtContext);avformat_close_input(&output_format_ctx);stateCallBack(FAIL);return ;}}// д���ļ�ͷif (avformat_write_header(output_format_ctx, nullptr) < 0) {//fprintf(stderr, "�޷�д������ļ�ͷ\n");avformat_close_input(&fmtContext);avformat_close_input(&output_format_ctx);stateCallBack(FAIL);return ;}int64_t videoIndex = 0;int64_t audioIndex = 0;AVRational  timeBase=fmtContext->streams[videoStreamIndex]->time_base;AVPacket packet;while (true){//����Ƿ�ֹͣif (m_bStop) {break;}if (av_read_frame(fmtContext, &packet) < 0) {break;}if (packet.stream_index == audioStreamIndex) {if (packet.pts*av_q2d(timeBase)>= m_startTime && packet.pts*av_q2d(timeBase)<= m_endTime) {if (audioIndex % m_interval == 0) {if(audioIndex==0){packet.pts = av_rescale_q(0, timeBase, output_format_ctx->streams[videoStreamIndex]->time_base);packet.dts = av_rescale_q(0, timeBase,  output_format_ctx->streams[videoStreamIndex]->time_base);}else{packet.pts = av_rescale_q(packet.pts-m_startTime/av_q2d(timeBase), timeBase, output_format_ctx->streams[videoStreamIndex]->time_base);packet.dts = av_rescale_q(packet.dts -m_startTime/av_q2d(timeBase), timeBase,  output_format_ctx->streams[videoStreamIndex]->time_base);}packet.duration = av_rescale_q(packet.duration, timeBase,  output_format_ctx->streams[videoStreamIndex]->time_base);av_write_frame(output_format_ctx, &packet);audioIndex++;continue;av_packet_unref(&packet);}audioIndex++;}}if (packet.stream_index == videoStreamIndex) {if (packet.pts*av_q2d(timeBase)>= m_startTime && packet.pts*av_q2d(timeBase)<= m_endTime) {qDebug()<<"============>sec:"<<packet.pts*av_q2d(timeBase)<<"<==============";if (videoIndex % m_interval == 0) {//                    packet.pts = packet.pts-m_startTime/av_q2d(timeBase);//                    packet.dts = packet.pts;packet.pts = av_rescale_q(packet.pts-m_startTime/av_q2d(timeBase), timeBase, output_format_ctx->streams[videoStreamIndex]->time_base);packet.dts = av_rescale_q(packet.dts -m_startTime/av_q2d(timeBase), timeBase,  output_format_ctx->streams[videoStreamIndex]->time_base);packet.duration = av_rescale_q(packet.duration, timeBase,  output_format_ctx->streams[videoStreamIndex]->time_base);av_write_frame(output_format_ctx, &packet);videoIndex++;av_packet_unref(&packet);continue;}videoIndex++;}}av_packet_unref(&packet);// ����Ƿ���ͣ{std::unique_lock<std::mutex> lock(m_mutex);cv.wait(lock, [this]{if (m_bPaused) {stateCallBack(PAUSE);}return !m_bPaused; });}}// д���ļ�βav_write_trailer(output_format_ctx);// �ر��ļ�avformat_close_input(&fmtContext);avio_close(output_format_ctx->pb);avformat_free_context(output_format_ctx);if (m_bStop) {stateCallBack(STOP);return;}stateCallBack(FINISH);
}void VideoEditerMp4::runMerge()
{stateCallBack(RUNNING);if (m_vecInputPaths.empty() || m_outputPath.empty()) {stateCallBack(FAIL);return;}AVFormatContext* fmtContext = avformat_alloc_context();if (avformat_open_input(&fmtContext,m_vecInputPaths.front().c_str() , nullptr, nullptr) < 0) {//fprintf(stderr, "�޷��򿪵�һ�������ļ�\n");stateCallBack(FAIL);return ;}if (avformat_find_stream_info(fmtContext, nullptr) < 0) {//fprintf(stderr, "�޷��ҵ���һ�������ļ�������Ϣ\n");avformat_close_input(&fmtContext);stateCallBack(FAIL);return ;}int videoStreamIndex = -1;for (int i = 0; i < fmtContext->nb_streams; i++) {if (fmtContext->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {videoStreamIndex = i;break;}}int audioStreamIndex = -1;for (int i = 0; i < fmtContext->nb_streams; i++) {if (fmtContext->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {audioStreamIndex = i;break;}}AVFormatContext* output_format_ctx = nullptr;if (avformat_alloc_output_context2(&output_format_ctx, nullptr, nullptr, m_outputPath.c_str())){avformat_close_input(&fmtContext);stateCallBack(FAIL);return;}// ���������ļ�����for (int i = 0; i < fmtContext->nb_streams; i++) {AVStream* stream = avformat_new_stream(output_format_ctx, nullptr);if (!stream) {avformat_close_input(&fmtContext);avformat_close_input(&output_format_ctx);stateCallBack(FAIL);return;}//        stream->time_base=fmtContext->streams[videoStreamIndex]->time_base;//        stream->duration=(m_endTime-m_startTime);if (avcodec_copy_context(stream->codec, fmtContext->streams[i]->codec)<0) {avformat_close_input(&fmtContext);avformat_close_input(&output_format_ctx);stateCallBack(FAIL);return;}if (avcodec_parameters_copy(stream->codecpar, fmtContext->streams[i]->codecpar) < 0) {avformat_close_input(&fmtContext);avformat_close_input(&output_format_ctx);stateCallBack(FAIL);return;}}// ������ļ�if (!(output_format_ctx->oformat->flags & AVFMT_NOFILE)) {if (avio_open(&output_format_ctx->pb, m_outputPath.c_str(), AVIO_FLAG_WRITE) < 0) {//            fprintf(stderr, "�޷�������ļ�\n");avformat_close_input(&fmtContext);avformat_close_input(&output_format_ctx);stateCallBack(FAIL);return ;}}// д���ļ�ͷif (avformat_write_header(output_format_ctx, nullptr) < 0) {//fprintf(stderr, "�޷�д������ļ�ͷ\n");avformat_close_input(&fmtContext);avformat_close_input(&output_format_ctx);stateCallBack(FAIL);return ;}int64_t videoIndex = 0;int64_t audioIndex = 0;AVRational  timeBase=fmtContext->streams[videoStreamIndex]->time_base;int64_t currentPts=0;AVPacket packet;for(int k=0;k<m_vecInputPaths.size();k++){//����Ƿ�ֹͣif (m_bStop) {break;}avformat_close_input(&fmtContext);if (avformat_open_input(&fmtContext,m_vecInputPaths.at(k).c_str() , nullptr, nullptr) < 0) {//fprintf(stderr, "�޷��򿪵�һ�������ļ�\n");stateCallBack(FAIL);return ;}if (avformat_find_stream_info(fmtContext, nullptr) < 0) {//fprintf(stderr, "�޷��ҵ���һ�������ļ�������Ϣ\n");avformat_close_input(&fmtContext);stateCallBack(FAIL);return ;}int videoStreamIndex = -1;for (int i = 0; i < fmtContext->nb_streams; i++) {if (fmtContext->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {videoStreamIndex = i;break;}}int audioStreamIndex = -1;for (int i = 0; i < fmtContext->nb_streams; i++) {if (fmtContext->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {audioStreamIndex = i;break;}}if(k!=0){currentPts+=(fmtContext->streams[videoStreamIndex]->duration/1000)/av_q2d(timeBase);}while (true){//����Ƿ�ֹͣif (m_bStop) {break;}if (av_read_frame(fmtContext, &packet) < 0) {break;}if (packet.stream_index == audioStreamIndex) {//if (packet.pts*av_q2d(timeBase)>= m_startTime && packet.pts*av_q2d(timeBase)<= m_endTime) {if (audioIndex % m_interval == 0) {if(audioIndex==0){packet.pts = av_rescale_q(0, timeBase, output_format_ctx->streams[videoStreamIndex]->time_base);packet.dts = av_rescale_q(0, timeBase,  output_format_ctx->streams[videoStreamIndex]->time_base);}else{packet.pts = av_rescale_q(packet.pts+currentPts, timeBase, output_format_ctx->streams[videoStreamIndex]->time_base);packet.dts = av_rescale_q(packet.dts+currentPts, timeBase,  output_format_ctx->streams[videoStreamIndex]->time_base);}packet.duration = av_rescale_q(packet.duration, timeBase,  output_format_ctx->streams[videoStreamIndex]->time_base);av_write_frame(output_format_ctx, &packet);audioIndex++;continue;av_packet_unref(&packet);}audioIndex++;//}}if (packet.stream_index == videoStreamIndex) {//if (packet.pts*av_q2d(timeBase)>= m_startTime && packet.pts*av_q2d(timeBase)<= m_endTime) {qDebug()<<"============>sec:"<<packet.pts*av_q2d(timeBase)<<"<==============";if (videoIndex % m_interval == 0) {//                    packet.pts = packet.pts-m_startTime/av_q2d(timeBase);//                    packet.dts = packet.pts;if(videoIndex==0){packet.pts = av_rescale_q(0, timeBase, output_format_ctx->streams[videoStreamIndex]->time_base);packet.dts = av_rescale_q(0, timeBase,  output_format_ctx->streams[videoStreamIndex]->time_base);}else{packet.pts = av_rescale_q(packet.pts+currentPts, timeBase, output_format_ctx->streams[videoStreamIndex]->time_base);packet.dts = av_rescale_q(packet.dts+currentPts, timeBase,  output_format_ctx->streams[videoStreamIndex]->time_base);}packet.duration = av_rescale_q(packet.duration, timeBase,  output_format_ctx->streams[videoStreamIndex]->time_base);av_write_frame(output_format_ctx, &packet);videoIndex++;av_packet_unref(&packet);continue;}videoIndex++;//}}av_packet_unref(&packet);// ����Ƿ���ͣ{std::unique_lock<std::mutex> lock(m_mutex);cv.wait(lock, [this]{if (m_bPaused) {stateCallBack(PAUSE);}return !m_bPaused; });}}}// д���ļ�βav_write_trailer(output_format_ctx);// �ر��ļ�avformat_close_input(&fmtContext);avio_close(output_format_ctx->pb);avformat_free_context(output_format_ctx);if (m_bStop) {stateCallBack(STOP);return;}stateCallBack(FINISH);
}

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