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最简单的基于FFmpeg的移动端样例系列文章列表：
最简单的基于FFmpeg的移动端样例：Android HelloWorld
最简单的基于FFmpeg的移动端样例：Android 视频解码器
最简单的基于FFmpeg的移动端样例：Android 视频解码器-单个库版
最简单的基于FFmpeg的移动端样例：Android 推流器
最简单的基于FFmpeg的移动端样例：Android 视频转码器
最简单的基于FFmpeg的移动端样例附件：Android 自带播放器
最简单的基于FFmpeg的移动端样例附件：SDL Android HelloWorld
最简单的基于FFmpeg的移动端样例：IOS HelloWorld
最简单的基于FFmpeg的移动端样例：IOS 视频解码器
最简单的基于FFmpeg的移动端样例：IOS 推流器
最简单的基于FFmpeg的移动端样例：IOS 视频转码器
最简单的基于FFmpeg的移动端样例附件：IOS自带播放器
最简单的基于FFmpeg的移动端样例：Windows Phone HelloWorld
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本文记录IOS平台下基于FFmpeg的推流器。
该演示样例C语言的源码来自于《最简单的基于FFMPEG的推流器》。
相关的概念就不再反复记录了。
源码
项目的文件夹结构如图所看到的。
/*** 最简单的基于FFmpeg的推流器-IOS* Simplest FFmpeg IOS Streamer** 雷霄骅 Lei Xiaohua* leixiaohua1020@126.com* 中国传媒大学/数字电视技术* Communication University of China / Digital TV Technology* http://blog.csdn.net/leixiaohua1020** 本程序是IOS平台下的推流器。它能够将本地文件以流媒体的形式推送出去。** This software is the simplest streamer in IOS.* It can stream local media files to streaming media server.*/#import "ViewController.h"
#include <libavformat/avformat.h>
#include <libavutil/mathematics.h>
#include <libavutil/time.h>@interface ViewController ()@end@implementation ViewController- (void)viewDidLoad {[super viewDidLoad];// Do any additional setup after loading the view, typically from a nib.
}- (void)didReceiveMemoryWarning {[super didReceiveMemoryWarning];// Dispose of any resources that can be recreated.
}- (IBAction)clickStreamButton:(id)sender {char input_str_full[500]={0};char output_str_full[500]={0};NSString *input_str= [NSString stringWithFormat:@"resource.bundle/%@",self.input.text];NSString *input_nsstr=[[[NSBundle mainBundle]resourcePath] stringByAppendingPathComponent:input_str];sprintf(input_str_full,"%s",[input_nsstr UTF8String]);sprintf(output_str_full,"%s",[self.output.text UTF8String]);printf("Input Path:%s\n",input_str_full);printf("Output Path:%s\n",output_str_full);AVOutputFormat *ofmt = NULL;//Input AVFormatContext and Output AVFormatContextAVFormatContext *ifmt_ctx = NULL, *ofmt_ctx = NULL;AVPacket pkt;char in_filename[500]={0};char out_filename[500]={0};int ret, i;int videoindex=-1;int frame_index=0;int64_t start_time=0;//in_filename = "cuc_ieschool.mov";//in_filename = "cuc_ieschool.h264";//in_filename = "cuc_ieschool.flv";//Input file URL//out_filename = "rtmp://localhost/publishlive/livestream";//Output URL[RTMP]//out_filename = "rtp://233.233.233.233:6666";//Output URL[UDP]strcpy(in_filename,input_str_full);strcpy(out_filename,output_str_full);av_register_all();//Networkavformat_network_init();//Inputif ((ret = avformat_open_input(&ifmt_ctx, in_filename, 0, 0)) < 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);//Outputavformat_alloc_output_context2(&ofmt_ctx, NULL, "flv", out_filename); //RTMP//avformat_alloc_output_context2(&ofmt_ctx, NULL, "mpegts", out_filename);//UDPif (!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++) {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;}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 |= CODEC_FLAG_GLOBAL_HEADER;}//Dump Format------------------av_dump_format(ofmt_ctx, 0, out_filename, 1);//Open output URLif (!(ofmt->flags & AVFMT_NOFILE)) {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;}}ret = avformat_write_header(ofmt_ctx, NULL);if (ret < 0) {printf( "Error occurred when opening output URL\n");goto end;}start_time=av_gettime();while (1) {AVStream *in_stream, *out_stream;//Get an AVPacketret = av_read_frame(ifmt_ctx, &pkt);if (ret < 0)break;//FIX：No PTS (Example: Raw H.264)//Simple Write PTSif(pkt.pts==AV_NOPTS_VALUE){//Write PTSAVRational 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);//Parameterspkt.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:Delayif(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;if (pts_time > now_time)av_usleep(pts_time - now_time);}in_stream = ifmt_ctx->streams[pkt.stream_index];out_stream = ofmt_ctx->streams[pkt.stream_index];/* copy packet *///Convert PTS/DTSpkt.pts = av_rescale_q_rnd(pkt.pts, in_stream->time_base, out_stream->time_base, (AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX));pkt.dts = av_rescale_q_rnd(pkt.dts, in_stream->time_base, out_stream->time_base, (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 Screenif(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;}return;}
@end
执行结果
App在手机上执行后的结果例如以下图所看到的。单击“Stream”，将会把位于resource.bundle中的“war3end.mp4”文件推送到“rtmp://www.velab.com.cn/live/test”的URL上。
使用视频播放器（在这里使用ffplay）能够查看推送的实时流，例如以下图所看到的。
下载
simplest ffmpeg mobile
项目主页
Github：https://github.com/leixiaohua1020/simplest_ffmpeg_mobile
开源中国：https://git.oschina.net/leixiaohua1020/simplest_ffmpeg_mobile
SourceForge：https://sourceforge.net/projects/simplestffmpegmobile/
CSDN工程下载地址：http://download.csdn.net/detail/leixiaohua1020/8924391
[Android]
simplest_android_player: 基于安卓接口的视频播放器
simplest_ffmpeg_android_helloworld: 安卓平台下基于FFmpeg的HelloWorld程序
simplest_ffmpeg_android_decoder: 安卓平台下最简单的基于FFmpeg的视频解码器
simplest_ffmpeg_android_decoder_onelib: 安卓平台下最简单的基于FFmpeg的视频解码器-单库版
simplest_ffmpeg_android_streamer: 安卓平台下最简单的基于FFmpeg的推流器
simplest_ffmpeg_android_transcoder: 安卓平台下移植的FFmpeg命令行工具
simplest_sdl_android_helloworld: 移植SDL到安卓平台的最简单程序
[IOS]
simplest_ios_player: 基于IOS接口的视频播放器
simplest_ffmpeg_ios_helloworld: IOS平台下基于FFmpeg的HelloWorld程序
simplest_ffmpeg_ios_decoder: IOS平台下最简单的基于FFmpeg的视频解码器
simplest_ffmpeg_ios_streamer: IOS平台下最简单的基于FFmpeg的推流器
simplest_ffmpeg_ios_transcoder: IOS平台下移植的ffmpeg.c命令行工具
simplest_sdl_ios_helloworld: 移植SDL到IOS平台的最简单程序