The simplest mobile-based ffmpeg example: IOS Video Decoder

<span id="Label3"></p>This document records the ffmpeg-based video decoder under the iOS platform. The source code for the example C language comes from the simplest ffmpeg+sdl-based video player. The related concepts are no longer duplicated.<br><br>Source<p><p>The directory structure of the Project.</p></p><p style="text-align: center;"><p style="text-align: center;"><br></p></p>The C code is in the VIEWCONTROLLER.M file, as shown in the Following.<br><pre name="code" class="objc">/** * Simplest FFmpeg based video Decoder-ios * simplest FFmpeg IOS Decoder * * Lei hua Lei Xiaohua * [email protected] * Communication university/digital TV Technology * Communication University of China/digital TV technology * http://blog.csdn.net/leixiaohua1020 * * This program is the simplest under the iOS platform based on FFmpeg Video Decoder. * It can decode the input video data into YUV pixel Data. * * This software are the simplest decoder based on FFmpeg in IOS. * It can decode video stream to Raw YUV Data. * */#import "ViewController.h" #include <libavcodec/avcodec.h> #include <libavformat/avformat.h> #include <libswscale/swscale.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 the can be recreated.} -(ibaction) clickdecodebutton: (id) Sender {avformatcontext*pformatctx; inti, videoindex; avcodeccontext*pcodecctx; avcodec*pcodec; Avframe*pframe, *pframeyuv; uint8_t *out_buffer; Avpacket *packet; int y_size; int ret, got_picture; struct Swscontext *img_convert_ctx; FILE *fp_yuv; int frame_cnt; clock_t time_start, time_finish; Double time_duration = 0.0; Char input_str_full[500]={0}; Char output_str_full[500]={0}; Char info[1000]={0}; NSString *input_str= [nsstring stringwithformat:@ "resource.bundle/%@", self.inputurl.text]; NSString *output_str= [nsstring stringwithformat:@ "resource.bundle/%@", self.outputurl.text]; NSString *input_nsstr=[[[nsbundle mainbundle]resourcepath] stringbyappendingpathcomponent:input_str]; NSString *output_nsstr=[[[nsbundle mainbundle]resourcepath] stringbyappendingpathcomponent:output_str]; sprintf (input_str_full, "%s", [input_nsstr utf8string]); sprintf (output_str_full, "%s", [output_nsstr utf8string]); printf ("Input path:%s\n", input_str_full); printf ("Output path:%s\n", output_str_full); Av_register_all (); Avformat_network_init (); Pformatctx = Avformat_alloc_context (); If (avformat_open_input (&pformatctx,input_str_full,null,null)!=0) {printf ("couldn ' t open input stream.\n"); return; } if (avformat_find_stream_info (pformatctx,null) <0) {printf ("couldn ' t find stream information.\n"); Return } videoindex=-1; For (i=0; i<pformatctx->nb_streams; I++) if (pformatctx->streams[i]->codec->codec_type==avmedia_type _video) {videoindex=i; Break } if (videoindex==-1) {printf ("couldn ' t find a video stream.\n"); Return } pcodecctx=pformatctx->streams[videoindex]->codec; Pcodec=avcodec_find_decoder (pcodecctx->codec_id); If (pcodec==null) {printf ("couldn ' t find codec.\n"); Return } if (avcodec_open2 (pcodecctx, pcodec,null) <0) {printf ("couldn ' t open codec.\n"); Return } Pframe=av_frame_alloc (); Pframeyuv=av_frame_alloc (); out_buffer= (uint8_t *) av_malloc (avpicture_get_size (pix_fmt_yuv420p, pcodecctx->width, pCodecCtx->height)); Avpicture_fill ((avpicture *) pframeyuv, out_buffer, pix_fmt_yuv420p, pcodecctx->width, pCodecCtx->height); packet= (avpacket *) av_malloc (sizeof (avpacket)); Img_convert_ctx = Sws_getcontext (pcodecctx->width, pcodecctx->height, pcodecctx->pix_fmt, pcodecctx->width, pcodecctx->height, pix_fmt_yuv420p, sws_bicubic, null, null, null); sprintf (info, "[Input]%s\n", [input_str utf8string]); sprintf (info, "%s[output]%s\n", info,[output_str utf8string]); sprintf (info, "%s[format]%s\n", info, pformatctx->iformat->name); sprintf (info, "%s[codec]%s\n", info, pcodecctx->codec->name); sprintf (info, "%s[resolution]%dx%d\n", info, pcodecctx->width,pcodecctx->height); Fp_yuv=fopen (output_str_full, "wb+"); If (fp_yuv==null) {printf ("cannot open ouTput file.\n "); Return } frame_cnt=0; Time_start = Clock (); While (av_read_frame (pformatctx, packet) >=0) {if (packet->stream_index==videoindex) {ret = avcodec_d Ecode_video2 (pcodecctx, pframe, &got_picture, packet); If (ret < 0) {printf ("Decode error.\n"); Return } if (got_picture) {sws_scale (img_convert_ctx, (const uint8_t* const*) pframe->data, pframe-&gt ; linesize, 0, pcodecctx->height, pframeyuv->data, pframeyuv->linesize); y_size=pcodecctx->width*pcodecctx->height; Fwrite (pframeyuv->data[0],1,y_size,fp_yuv); Y fwrite (pframeyuv->data[1],1,y_size/4,fp_yuv); U fwrite (pframeyuv->data[2],1,y_size/4,fp_yuv); V//output Info Char pictype_str[10]={0}; Switch (pframe->pict_type){case av_picture_type_i:sprintf (pictype_str, "I"); Case av_picture_type_p:sprintf (pictype_str, "P"); Case av_picture_type_b:sprintf (pictype_str, "B"); default:sprintf (pictype_str, "other"); } printf ("Frame Index:%5d. type:%s\n ", frame_cnt,pictype_str); frame_cnt++; }} Av_free_packet (packet); }//flush Decoder//fix:flush Frames remained in Codec while (1) {ret = Avcodec_decode_video2 (pcodecctx, pframe, &got_picture, packet); If (ret < 0) break; If (!got_picture) break; Sws_scale (img_convert_ctx, (const uint8_t* const*) pframe->data, pframe->linesize, 0, pcodecctx->height, pframeyuv->data, pframeyuv->linesize); int y_size=pcodecctx->width*pcodecctx->height; Fwrite (pframeyuv->data[0],1,y_size,fp_yuv); Y fwrite (pframeyuv->data[1],1,y_size/4,fp_yuv); U fwrite (pframeyuv->data[2],1,y_size/4,fp_yuv); V//output Info Char pictype_str[10]={0}; Switch (pframe->pict_type) {case av_picture_type_i:sprintf (pictype_str, "I"); Case av_picture_type_p:sprintf (pictype_str, "P"); Case av_picture_type_b:sprintf (pictype_str, "B"); default:sprintf (pictype_str, "other"); } printf ("Frame Index:%5d. type:%s\n ", frame_cnt,pictype_str); frame_cnt++; } time_finish = Clock (); time_duration= (double) (time_finish-time_start); sprintf (info, "%s[time]%fus\n", info,time_duration); sprintf (info, "%s[count]%d\n", info,frame_cnt); Sws_freecontext (img_convert_ctx); Fclose (fp_yuv); Av_frame_free (&pframeyuv); Av_frame_free (&pframe); Avcodec_close (pcodecctx); Avformat_close_input (&pformatctx); NSString * INfo_ns = [nsstring stringwithformat:@ "%s", info]; self.infomation.text=info_ns;} @end</pre><pre name="code" class="objc"><pre name="code" class="objc"></pre></pre><p><p><br></p></p>Run results<p><p>The app runs on the phone as shown in the Results. Clicking "Decode" will decode the "sintel.mov" file in Resource.bundle to "sintel.yuv" file and store it in the same directory.</p></p><p style="text-align: center;"><p style="text-align: center;"><br></p></p>The resulting file is as Shown.<br><br>Download<br><strong><strong>simplest ffmpeg mobile</strong></strong><br><br><p><p><strong>Project Home</strong></p></p><p><p>Github:https://github.com/leixiaohua1020/simplest_ffmpeg_mobile</p></p><p><p>Open Source China: https://git.oschina.net/leixiaohua1020/simplest_ffmpeg_mobile<br></p></p><p><p><br></p></p><p><p>CSDN project: http://download.csdn.net/detail/leixiaohua1020/8924391</p></p><p><p><br></p></p>This solution contains various examples of using FFMPEG to process multimedia on the mobile side:<br> <blockquote style="margin: 0 0 0 40px; border: none; padding: 0px;"> <blockquote style="margin: 0 0 0 40px; border: none; padding: 0px;"> [Android] <br>Simplest_android_player: Android interface-based Video player <br>Simplest_ffmpeg_android_helloworld: ffmpeg-based HelloWorld program under Android platform <br>Simplest_ffmpeg_android_decoder: The simplest ffmpeg-based video decoder on the Android platform <br>Simplest_ffmpeg_android_decoder_onelib: The simplest ffmpeg-based video decoder on the Android Platform-library edition <br>Simplest_ffmpeg_android_streamer: The simplest ffmpeg-based push-to-flow device under the Android platform <br>Simplest_ffmpeg_android_transcoder: FFmpeg command-line tool ported under Android platform <br>Simplest_sdl_android_helloworld: the simplest program for porting SDL to the Android platform <br>[IOS] <br>Simplest_ios_player: Video player based on iOS interface <br>HelloWorld program based on FFmpeg under the Simplest_ffmpeg_ios_helloworld:ios platform <br> <span style="color:#ff0000;">The simplest ffmpeg-based video decoder under the Simplest_ffmpeg_ios_decoder:ios platform</span> <br>The simplest ffmpeg based on the Simplest_ffmpeg_ios_streamer:ios platform <br>FFMPEG.C command-line tool ported under Simplest_ffmpeg_ios_transcoder:ios Platform <br>Simplest_sdl_ios_helloworld: The simplest program to migrate SDL to the iOS platform </blockquote> </blockquote><br><br> <p style="font-size:12px;"><p style="font-size:12px;">Copyright Notice: This article for Bo Master original article, without Bo Master permission not Reproduced.</p></p> <p><p>The simplest mobile-based ffmpeg example: IOS Video Decoder</p></p></span>