代码及工程见https://download.csdn.net/download/daqinzl/88156926
开发工具：visual studio 2019
播放，采用ffmpeg工具集里的ffplay.exe, 执行命令 ffplay udp://238.1.1.10:6016
主要代码如下:
#include "pch.h"
#include <iostream>
using namespace std;
#include <stdio.h>
#define __STDC_CONSTANT_MACROS
extern "C"
{
#include "include/libavcodec/avcodec.h"
#include "include/libavformat/avformat.h"
#include "include/libswscale/swscale.h"
#include "include/libavdevice/avdevice.h"
#include "include/libavutil/imgutils.h"
#include "include/libavutil/opt.h"
#include "include/libavutil/imgutils.h"
#include "include/libavutil/mathematics.h"
#include "include/libavutil/time.h"
};
#pragma comment (lib,"avcodec.lib")
#pragma comment (lib,"avdevice.lib")
#pragma comment (lib,"avfilter.lib")
#pragma comment (lib,"avformat.lib")
#pragma comment (lib,"avutil.lib")
#pragma comment (lib,"swresample.lib")
#pragma comment (lib,"swscale.lib")
int main(int argc, char* argv[])
{
AVOutputFormat* ofmt = NULL;
//输入对应一个AVFormatContext，输出对应一个AVFormatContext
//（Input AVFormatContext and Output AVFormatContext）
AVFormatContext* ifmt_ctx = NULL, * ofmt_ctx = NULL;
AVPacket pkt;
const char* in_filename, * out_filename;
int ret, i;
int videoindex = -1;
int frame_index = 0;
int64_t start_time = 0;
in_filename = "udp://238.1.1.11:1234";//可以为本地文件或者其他形式的直播流、设备等
in_filename = "d:/mv/test.mp4";
out_filename = "udp://238.1.1.10:6016";
av_register_all();
//Network
avformat_network_init();
if (true) {
}
else {
end:
avformat_close_input(&ifmt_ctx);
/* close output */
if (ofmt_ctx && !(ofmt->flags & AVFMT_NOFILE))
avio_close(ofmt_ctx->pb);
avformat_free_context(ofmt_ctx);
if (ret < 0 && ret != AVERROR_EOF) {
printf("Error occurred.\n");
return -1;
}
return 0;
}
AVDictionary* inputdic = NULL;
//如果不设置的话，在输入源是直播流的时候，会花屏。单位bytes
av_dict_set(&inputdic, "buffer_size", "10485760", 0);
av_dict_set(&inputdic, "reuse", "1", 0);
//输入（Input）
if ((ret = avformat_open_input(&ifmt_ctx, in_filename, 0, &inputdic)) < 0) {
printf("Could not open input file.");
goto end;
}
if ((ret = avformat_find_stream_info(ifmt_ctx, 0)) < 0) {
printf("Failed to retrieve input stream information");
goto end;
}
for (i = 0; i < ifmt_ctx->nb_streams; i++)
if (ifmt_ctx->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
videoindex = i;
break;
}
av_dump_format(ifmt_ctx, 0, in_filename, 0);
//输出（Output）
avformat_alloc_output_context2(&ofmt_ctx, NULL, "mpegts", out_filename);//UDP
if (!ofmt_ctx) {
printf("Could not create output context\n");
ret = AVERROR_UNKNOWN;
goto end;
}
ofmt = ofmt_ctx->oformat;
for (i = 0; i < ifmt_ctx->nb_streams; i++) {
//根据输入流创建输出流（Create output AVStream according to input AVStream）
AVStream* in_stream = ifmt_ctx->streams[i];
AVStream* out_stream = avformat_new_stream(ofmt_ctx, in_stream->codec->codec);
if (!out_stream) {
printf("Failed allocating output stream\n");
ret = AVERROR_UNKNOWN;
goto end;
}
//复制AVCodecContext的设置（Copy the settings of AVCodecContext）
//tanzhenwen
ret = avcodec_parameters_copy(out_stream->codecpar, ifmt_ctx->streams[i]->codecpar);
if (ret < 0) {
printf("Failed to copy parameters from input to output stream codec context\n");
goto end;
}
/* ret = avcodec_copy_context(out_stream->codec, in_stream->codec);
if (ret < 0) {
printf("Failed to copy context from input to output stream codec context\n");
goto end;
}*/
out_stream->codec->codec_tag = 0;
if (ofmt_ctx->oformat->flags & AVFMT_GLOBALHEADER)
out_stream->codec->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;
}
//Dump Format------------------
av_dump_format(ofmt_ctx, 0, out_filename, 1);
//打开输出URL（Open output URL）
if (!(ofmt->flags & AVFMT_NOFILE)) {
AVDictionary* dic = NULL;
av_dict_set(&dic, "pkt_size", "1316", 0); //Maximum UDP packet size
//av_dict_set(&dic, "fifo_size", "18800", 0);
//av_dict_set(&dic, "buffer_size", "1000000", 0);
//av_dict_set(&dic, "bitrate", "11000000", 0);
//av_dict_set(&dic, "buffer_size", "1000000", 0);//1316
av_dict_set(&dic, "reuse", "1", 0);
ret = avio_open2(&ofmt_ctx->pb, out_filename, AVIO_FLAG_WRITE, NULL, &dic);
//ret = avio_open(&ofmt_ctx->pb, out_filename, AVIO_FLAG_WRITE);
if (ret < 0) {
printf("Could not open output URL '%s'", out_filename);
goto end;
}
}
//av_opt_set(ofmt_ctx->priv_data, "muxrate", "11000000", 0);
av_opt_set(ofmt_ctx->priv_data, "MpegTSWrite", "1", 0);
av_opt_set(ofmt_ctx->priv_data, "pes_payload_size", "300", 0);
//写文件头（Write file header）
ret = avformat_write_header(ofmt_ctx, NULL);
if (ret < 0) {
printf("Error occurred when opening output URL\n");
goto end;
}
start_time = av_gettime();
int64_t deltpts = 0;
while (1) {
AVStream* in_stream, * out_stream;
//获取一个AVPacket（Get an AVPacket）
ret = av_read_frame(ifmt_ctx, &pkt);
if (ret < 0)
break;
//FIX：No PTS (Example: Raw H.264)
//Simple Write PTS
if (pkt.pts == AV_NOPTS_VALUE) {
//Write PTS
AVRational time_base1 = ifmt_ctx->streams[videoindex]->time_base;
//Duration between 2 frames (us)
int64_t calc_duration = (double)AV_TIME_BASE / av_q2d(ifmt_ctx->streams[videoindex]->r_frame_rate);
//Parameters
pkt.pts = (double)(frame_index * calc_duration) / (double)(av_q2d(time_base1) * AV_TIME_BASE);
pkt.dts = pkt.pts;
pkt.duration = (double)calc_duration / (double)(av_q2d(time_base1) * AV_TIME_BASE);
}
//Important:Delay
if (pkt.stream_index == videoindex) {
AVRational time_base = ifmt_ctx->streams[videoindex]->time_base;
AVRational time_base_q = { 1,AV_TIME_BASE };
int64_t pts_time = av_rescale_q(pkt.dts, time_base, time_base_q);
int64_t now_time = av_gettime() - start_time;
static bool first = true;
if (first)
{
deltpts = pts_time;
first = false;
}
if (pts_time - deltpts > now_time)
av_usleep(pts_time - deltpts - now_time);
}
in_stream = ifmt_ctx->streams[pkt.stream_index];
out_stream = ofmt_ctx->streams[pkt.stream_index];
//if (pkt.stream_index == videoindex) {
// out_stream->time_base = AVRational{ 1, 25 };
//}
/* copy packet */
//转换PTS/DTS（Convert PTS/DTS）
pkt.pts = av_rescale_q_rnd(pkt.pts, in_stream->time_base, out_stream->time_base, (AVRounding)(AV_ROUND_NEAR_INF | AV_ROUND_PASS_MINMAX));
pkt.dts = av_rescale_q_rnd(pkt.dts, in_stream->time_base, out_stream->time_base, (AVRounding)(AV_ROUND_NEAR_INF | AV_ROUND_PASS_MINMAX));
pkt.duration = av_rescale_q(pkt.duration, in_stream->time_base, out_stream->time_base);
pkt.pos = -1;
//Print to Screen
if (pkt.stream_index == videoindex) {
//printf("Send %8d video frames to output URL\n", frame_index);
frame_index++;
}
//ret = av_write_frame(ofmt_ctx, &pkt);
ret = av_interleaved_write_frame(ofmt_ctx, &pkt);
if (ret < 0) {
printf("Error muxing packet\n");
break;
}
av_free_packet(&pkt);
}
//写文件尾（Write file trailer）
av_write_trailer(ofmt_ctx);
//end:
avformat_close_input(&ifmt_ctx);
/* close output */
if (ofmt_ctx && !(ofmt->flags & AVFMT_NOFILE))
avio_close(ofmt_ctx->pb);
avformat_free_context(ofmt_ctx);
if (ret < 0 && ret != AVERROR_EOF) {
printf("Error occurred.\n");
return -1;
}
return 0;
}