王纲文件分隔
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#ifndef PCH_H #define PCH_H extern "C" { #include "libavutil/opt.h" #include "libavutil/channel_layout.h" #include "libavutil/common.h" #include "libavutil/imgutils.h" #include "libavutil/mathematics.h" #include "libavutil/samplefmt.h" #include "libavutil/time.h" #include "libavutil/fifo.h" #include "libavcodec/avcodec.h" #include "libavformat/avformat.h" #include "libavformat/avio.h" //#include "libavfilter/avfiltergraph.h" #include "libavfilter/avfilter.h" #include "libavfilter/buffersink.h" #include "libavfilter/buffersrc.h" #include "libswscale/swscale.h" #include "libswresample/swresample.h" } #endif
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// CGFileCut.cpp : 定义控制台应用程序的入口点。 // /* Copyright [c] 2017-2027 By Gang.Wang Allrights Reserved This file give a simple example of how to cut video file. Any questions, you can join QQ group for help, QQ Group number:127903734. */ //#include "stdafx.h" #include <string> #include <memory> #include <thread> #include <iostream> using namespace std; #include "pch.h" AVFormatContext *inputContext = nullptr; AVFormatContext * outputContext; int64_t lastReadPacktTime ; static int interrupt_cb(void *ctx) { int timeout = 3; if(av_gettime() - lastReadPacktTime > timeout *1000 *1000) { return -1; } return 0; } int OpenInput(string inputUrl) { inputContext = avformat_alloc_context(); lastReadPacktTime = av_gettime(); inputContext->interrupt_callback.callback = interrupt_cb; int ret = avformat_open_input(&inputContext, inputUrl.c_str(), nullptr,nullptr); if(ret < 0) { av_log(NULL, AV_LOG_ERROR, "Input file open input failed\n"); return ret; } ret = avformat_find_stream_info(inputContext,nullptr); if(ret < 0) { av_log(NULL, AV_LOG_ERROR, "Find input file stream inform failed\n"); } else { av_log(NULL, AV_LOG_FATAL, "Open input file %s success\n",inputUrl.c_str()); } return ret; } shared_ptr<AVPacket> ReadPacketFromSource() { shared_ptr<AVPacket> packet(static_cast<AVPacket*>(av_malloc(sizeof(AVPacket))), [&](AVPacket *p) { av_packet_free(&p); av_freep(&p);}); av_init_packet(packet.get()); lastReadPacktTime = av_gettime(); int ret = av_read_frame(inputContext, packet.get()); if(ret >= 0) { return packet; } else { return nullptr; } } int OpenOutput(string outUrl) { int ret = avformat_alloc_output_context2(&outputContext, nullptr, "flv", outUrl.c_str()); if(ret < 0) { av_log(NULL, AV_LOG_ERROR, "open output context failed\n"); goto Error; } ret = avio_open2(&outputContext->pb, outUrl.c_str(), AVIO_FLAG_WRITE,nullptr, nullptr); if(ret < 0) { av_log(NULL, AV_LOG_ERROR, "open avio failed"); goto Error; } for(int i = 0; i < inputContext->nb_streams; i++) { AVStream * stream = avformat_new_stream(outputContext, inputContext->streams[i]->codec->codec); ret = avcodec_copy_context(stream->codec, inputContext->streams[i]->codec); if(ret < 0) { av_log(NULL, AV_LOG_ERROR, "copy coddec context failed"); goto Error; } } ret = avformat_write_header(outputContext, nullptr); if(ret < 0) { av_log(NULL, AV_LOG_ERROR, "format write header failed"); goto Error; } av_log(NULL, AV_LOG_FATAL, " Open output file success %s\n",outUrl.c_str()); return ret ; Error: if(outputContext) { for(int i = 0; i < outputContext->nb_streams; i++) { avcodec_close(outputContext->streams[i]->codec); } avformat_close_input(&outputContext); } return ret ; } void Init() { av_register_all(); avfilter_register_all(); avformat_network_init(); av_log_set_level(AV_LOG_ERROR); } void CloseInput() { if(inputContext != nullptr) { avformat_close_input(&inputContext); } } void CloseOutput() { if(outputContext != nullptr) { for(int i = 0 ; i < outputContext->nb_streams; i++) { AVCodecContext *codecContext = outputContext->streams[i]->codec; avcodec_close(codecContext); } avformat_close_input(&outputContext); } } int WritePacket(shared_ptr<AVPacket> packet) { auto inputStream = inputContext->streams[packet->stream_index]; auto outputStream = outputContext->streams[packet->stream_index]; return av_interleaved_write_frame(outputContext, packet.get()); } int main(int argc, char* argv[]) { //第20S开始,去掉8S int startPacketNum = 500; int discardtPacketNum = 200; int packetCount = 0; int64_t lastPacketPts = AV_NOPTS_VALUE; int64_t lastPts = AV_NOPTS_VALUE; Init(); int ret = OpenInput("D:\\test.flv"); if(ret >= 0) { ret = OpenOutput("D:\\out1.flv"); } if(ret <0) goto Error; while(true) { auto packet = ReadPacketFromSource(); if(packet) { packetCount++; if(packetCount <= 500 || packetCount >= 700) { if(packetCount >= 700) { if(packet->pts - lastPacketPts > 120) { lastPts = lastPacketPts ; } else { auto diff = packet->pts - lastPacketPts; lastPts += diff; } } lastPacketPts = packet->pts; if(lastPts != AV_NOPTS_VALUE) { packet->pts = packet->dts = lastPts; } ret = WritePacket(packet); } } else { break; } } cout <<"Cut File End "<<endl; Error: CloseInput(); CloseOutput(); while(true) { this_thread::sleep_for(chrono::seconds(100)); } return 0; }