【ffmpeg学习】Tutorial 04: Spawning Threads 将解析线程与视频解码线程分开

环境

FFmpeg：2013年9月9日 github master版本

SDL：SDL2

系统：macos 10.8 64位

ffmpeg编译参数：

./configure --cc=clang --disable-everything  --enable-libfdk_aac --enable-libmp3lame --enable-protocol=file --enable-protocol=file --enable-decoder=aac --enable-decoder=aac --enable-decoder=mp3 --enable-encoder=libmp3lame --enable-encoder=libfdk_aac --enable-demuxer=aac --enable-demuxer=mp3 --enable-muxer=adts --enable-muxer=mp3 --enable-parser=aac --enable-decoder=flv --enable-decoder=h264 --enable-decoder=mpeg4 --enable-demuxer=avi --enable-demuxer=flv --enable-demuxer=h264 --enable-muxer=mp4 --enable-muxer=flv

代码源自

http://dranger.com/ffmpeg/tutorial04.html

修改后版本

// tutorial04.c
// A pedagogical video player that will stream through every video frame as fast as it can,
// and play audio (out of sync).
//
// This tutorial was written by Stephen Dranger ([email protected]).
//
// Code based on FFplay, Copyright (c) 2003 Fabrice Bellard,
// and a tutorial by Martin Bohme ([email protected])
// Tested on Gentoo, CVS version 5/01/07 compiled with GCC 4.1.1
//
// Use the Makefile to build all the samples.
//
// Run using
// tutorial04 myvideofile.mpg
//
// to play the video stream on your screen.



#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#include <libavformat/avio.h>
#include <libswscale/swscale.h>
#include <libavutil/avstring.h>

#include <SDL2/SDL.h>
#include <SDL2/SDL_thread.h>

#ifdef __MINGW32__
#undef main /* Prevents SDL from overriding main() */
#endif

#include <stdio.h>
#include <math.h>

#define SDL_AUDIO_BUFFER_SIZE 1024
#define MAX_AUDIO_FRAME_SIZE 192000

#define MAX_AUDIOQ_SIZE (5 * 16 * 1024)
#define MAX_VIDEOQ_SIZE (5 * 256 * 1024)

#define FF_ALLOC_EVENT   (SDL_USEREVENT)
#define FF_REFRESH_EVENT (SDL_USEREVENT + 1)
#define FF_QUIT_EVENT (SDL_USEREVENT + 2)

#define VIDEO_PICTURE_QUEUE_SIZE 1

typedef struct PacketQueue {
    AVPacketList *first_pkt, *last_pkt;
    int nb_packets;
    int size;
    SDL_mutex *mutex;
    SDL_cond *cond;
} PacketQueue;


typedef struct VideoPicture {
    //SDL_Texture *texture;
    AVFrame* rawdata;
    //SDL_Overlay *bmp;
    int width, height; /* source height & width */
    int allocated;
} VideoPicture;

typedef struct VideoState {
    
    AVFormatContext *pFormatCtx;
    int             videoStream, audioStream;
    AVStream        *audio_st;
    PacketQueue     audioq;
    uint8_t         audio_buf[(MAX_AUDIO_FRAME_SIZE * 3) / 2];
    unsigned int    audio_buf_size;
    unsigned int    audio_buf_index;
    AVFrame         audio_frame;
    AVPacket        audio_pkt;
    uint8_t         *audio_pkt_data;
    int             audio_pkt_size;
    AVStream        *video_st;
    PacketQueue     videoq;
    
    VideoPicture    pictq[VIDEO_PICTURE_QUEUE_SIZE];
    int             pictq_size, pictq_rindex, pictq_windex;
    SDL_mutex       *pictq_mutex;
    SDL_cond        *pictq_cond;
    
    SDL_Thread      *parse_tid;
    SDL_Thread      *video_tid;
    
    char            filename[1024];
    int             quit;
    
    AVIOContext     *io_context;
    struct SwsContext *sws_ctx;
} VideoState;



/* Since we only have one decoding thread, the Big Struct
 can be global in case we need it. */
VideoState *global_video_state;



void packet_queue_init(PacketQueue *q) {
    memset(q, 0, sizeof(PacketQueue));
    q->mutex = SDL_CreateMutex();
    q->cond = SDL_CreateCond();
}
int packet_queue_put(PacketQueue *q, AVPacket *pkt) {
    
    AVPacketList *pkt1;
    if(av_dup_packet(pkt) < 0) {
        return -1;
    }
    pkt1 = av_malloc(sizeof(AVPacketList));
    if (!pkt1)
        return -1;
    pkt1->pkt = *pkt;
    pkt1->next = NULL;
    
    SDL_LockMutex(q->mutex);
    
    if (!q->last_pkt)
        q->first_pkt = pkt1;
    else
        q->last_pkt->next = pkt1;
    q->last_pkt = pkt1;
    q->nb_packets++;
    q->size += pkt1->pkt.size;
    SDL_CondSignal(q->cond);
    
    SDL_UnlockMutex(q->mutex);
    return 0;
}
static int packet_queue_get(PacketQueue *q, AVPacket *pkt, int block)
{
    AVPacketList *pkt1;
    int ret;
    
    SDL_LockMutex(q->mutex);
    
    for(;;) {
        
        if(global_video_state->quit) {
            ret = -1;
            break;
        }
        
        pkt1 = q->first_pkt;
        if (pkt1) {
            q->first_pkt = pkt1->next;
            if (!q->first_pkt)
                q->last_pkt = NULL;
            q->nb_packets--;
            q->size -= pkt1->pkt.size;
            *pkt = pkt1->pkt;
            av_free(pkt1);
            ret = 1;
            break;
        } else if (!block) {
            ret = 0;
            break;
        } else {
            SDL_CondWait(q->cond, q->mutex);
        }
    }
    SDL_UnlockMutex(q->mutex);
    return ret;
}

int audio_decode_frame(VideoState *is) {
    int len1, data_size = 0;
    AVPacket *pkt = &is->audio_pkt;
    
    for(;;) {
        while(is->audio_pkt_size > 0) {
            int got_frame = 0;
            len1 = avcodec_decode_audio4(is->audio_st->codec, &is->audio_frame, &got_frame, pkt);
            if(len1 < 0) {
                /* if error, skip frame */
                is->audio_pkt_size = 0;
                break;
            }
            if (got_frame)
            {
                data_size =
                av_samples_get_buffer_size
                (
                 NULL,
                 is->audio_st->codec->channels,
                 is->audio_frame.nb_samples,
                 is->audio_st->codec->sample_fmt,
                 1
                 );
                memcpy(is->audio_buf, is->audio_frame.data[0], data_size);
            }
            is->audio_pkt_data += len1;
            is->audio_pkt_size -= len1;
            if(data_size <= 0) {
                /* No data yet, get more frames */
                continue;
            }
            /* We have data, return it and come back for more later */
            return data_size;
        }
        if(pkt->data)
            av_free_packet(pkt);
        
        if(is->quit) {
            return -1;
        }
        /* next packet */
        if(packet_queue_get(&is->audioq, pkt, 1) < 0) {
            return -1;
        }
        is->audio_pkt_data = pkt->data;
        is->audio_pkt_size = pkt->size;
    }
}

void audio_callback(void *userdata, Uint8 *stream, int len) {
    
    VideoState *is = (VideoState *)userdata;
    int len1, audio_size;
    
    while(len > 0) {
        if(is->audio_buf_index >= is->audio_buf_size) {
            /* We have already sent all our data; get more */
            audio_size = audio_decode_frame(is);
            if(audio_size < 0) {
                /* If error, output silence */
                is->audio_buf_size = 1024;
                memset(is->audio_buf, 0, is->audio_buf_size);
            } else {
                is->audio_buf_size = audio_size;
            }
            is->audio_buf_index = 0;
        }
        len1 = is->audio_buf_size - is->audio_buf_index;
        if(len1 > len)
            len1 = len;
        memcpy(stream, (uint8_t *)is->audio_buf + is->audio_buf_index, len1);
        len -= len1;
        stream += len1;
        is->audio_buf_index += len1;
    }
}

static Uint32 sdl_refresh_timer_cb(Uint32 interval, void *opaque) {
    SDL_Event event;
    event.type = FF_REFRESH_EVENT;
    event.user.data1 = opaque;
    SDL_PushEvent(&event);
    return 0; /* 0 means stop timer */
}

/* schedule a video refresh in 'delay' ms */
static void schedule_refresh(VideoState *is, int delay) {
    SDL_AddTimer(delay, sdl_refresh_timer_cb, is);
}

void video_display(VideoState *is,SDL_Renderer* renderer,SDL_Texture* texture) {
    
    SDL_Rect rect;
    VideoPicture *vp;
    //AVPicture pict;
    float aspect_ratio;
    //int w=0, h=0, x=0, y=0;
    //screen->w;
    //int i;
    
    //renderer->w;
    
    vp = &is->pictq[is->pictq_rindex];
    if(vp->rawdata) {
        if(is->video_st->codec->sample_aspect_ratio.num == 0) {
            aspect_ratio = 0;
        } else {
            aspect_ratio = av_q2d(is->video_st->codec->sample_aspect_ratio) *
            is->video_st->codec->width / is->video_st->codec->height;
        }
        if(aspect_ratio <= 0.0) {
            aspect_ratio = (float)is->video_st->codec->width /
            (float)is->video_st->codec->height;
        }
        //screen->h;
//        h = screen->h;
//        w = ((int)rint(h * aspect_ratio)) & -3;
//        if(w > screen->w) {
//            w = screen->w;
//            h = ((int)rint(w / aspect_ratio)) & -3;
//        }
//        x = (screen->w - w) / 2;
//        y = (screen->h - h) / 2;
        
        rect.x = 0;
        rect.y = 0;
        rect.w = vp->width;
        rect.h = vp->height;
        
        //SDL_SetRenderDrawColor(renderer, 120, 0, 0, 255);
        //SDL_RenderFillRect(renderer, &rect);
        
        SDL_UpdateTexture( texture, &rect, vp->rawdata->data[0], vp->rawdata->linesize[0] );
        SDL_RenderClear( renderer );
        SDL_RenderCopy( renderer,texture , &rect, &rect );
        SDL_RenderPresent( renderer );
        
        //SDL_DisplayYUVOverlay(vp->bmp, &rect);
    }
}

void video_refresh_timer(void *userdata,SDL_Renderer* renderer,SDL_Texture* texture) {
    
    VideoState *is = (VideoState *)userdata;
    // vp is used in later tutorials for synchronization
    //VideoPicture *vp;
    
    if(is->video_st) {
        if(is->pictq_size == 0) {
            schedule_refresh(is, 1);
        } else {
            //vp = &is->pictq[is->pictq_rindex];
            /* Now, normally here goes a ton of code
             about timing, etc. we're just going to
             guess at a delay for now. You can
             increase and decrease this value and hard code
             the timing - but I don't suggest that ;)
             We'll learn how to do it for real later.
             */
            schedule_refresh(is, 30);
            
            /* show the picture! */
            video_display(is,renderer,texture);
            
            /* update queue for next picture! */
            if(++is->pictq_rindex == VIDEO_PICTURE_QUEUE_SIZE) {
                is->pictq_rindex = 0;
            }
            SDL_LockMutex(is->pictq_mutex);
            is->pictq_size--;
            SDL_CondSignal(is->pictq_cond);
            SDL_UnlockMutex(is->pictq_mutex);
        }
    } else {
        schedule_refresh(is, 100);
    }
}

void alloc_picture(void *userdata,SDL_Renderer* renderer) {
    
    VideoState *is = (VideoState *)userdata;
    VideoPicture *vp;
    
    vp = &is->pictq[is->pictq_windex];
    if(vp->rawdata) {
        // we already have one make another, bigger/smaller
        //SDL_DestroyTexture(vp->texture);
        //vp->texture = NULL;
        av_free(vp->rawdata);
        //SDL_FreeYUVOverlay(vp->bmp);
    }
    // Allocate a place to put our YUV image on that screen
//    vp->texture = SDL_CreateYUVOverlay(is->video_st->codec->width,
//                                   is->video_st->codec->height,
//                                   SDL_YV12_OVERLAY,
//                                   screen);
    
    
    vp->width = is->video_st->codec->width;
    vp->height = is->video_st->codec->height;
    
    
    AVCodecContext *pCodecCtx = NULL;
    pCodecCtx = is->video_st->codec;
    
    AVFrame* pFrameYUV = avcodec_alloc_frame();
    if( pFrameYUV == NULL )
        return;
    int numBytes = avpicture_get_size(PIX_FMT_YUV420P, pCodecCtx->width,
                                      pCodecCtx->height);
    uint8_t* buffer = (uint8_t *)av_malloc(numBytes*sizeof(uint8_t));
    
    avpicture_fill((AVPicture *)pFrameYUV, buffer, PIX_FMT_YUV420P,
                   pCodecCtx->width, pCodecCtx->height);
    
    
    vp->rawdata = pFrameYUV;
    
    //SDL_CreateTexture(renderer, SDL_PIXELFORMAT_IYUV, SDL_TEXTUREACCESS_STREAMING, vp->width, vp->height);
    
    SDL_LockMutex(is->pictq_mutex);
    vp->allocated = 1;
    SDL_CondSignal(is->pictq_cond);
    SDL_UnlockMutex(is->pictq_mutex);
    
}

int queue_picture(VideoState *is, AVFrame *pFrame) {
    
    VideoPicture *vp;
    //AVCodecContext *pCodecCtx;
    
    
    
    
    /* wait until we have space for a new pic */
    SDL_LockMutex(is->pictq_mutex);
    while(is->pictq_size >= VIDEO_PICTURE_QUEUE_SIZE &&
          !is->quit) {
        SDL_CondWait(is->pictq_cond, is->pictq_mutex);
    }
    SDL_UnlockMutex(is->pictq_mutex);
    
    if(is->quit)
        return -1;
    
    // windex is set to 0 initially
    vp = &is->pictq[is->pictq_windex];
    
    /* allocate or resize the buffer! */
    if(!vp->rawdata ||
       vp->width != is->video_st->codec->width ||
       vp->height != is->video_st->codec->height) {
        SDL_Event event;
        
        vp->allocated = 0;
        /* we have to do it in the main thread */
        event.type = FF_ALLOC_EVENT;
        event.user.data1 = is;
        SDL_PushEvent(&event);
        
        /* wait until we have a picture allocated */
        SDL_LockMutex(is->pictq_mutex);
        while(!vp->allocated && !is->quit) {
            SDL_CondWait(is->pictq_cond, is->pictq_mutex);
        }
        SDL_UnlockMutex(is->pictq_mutex);
        if(is->quit) {
            return -1;
        }
    }
    
    
    
    
    /* We have a place to put our picture on the queue */
    
    if(vp->rawdata) {
        
        //SDL_LockYUVOverlay(vp->bmp);
        
        /* point pict at the queue */
        
//        pict.data[0] = vp->bmp->pixels[0];
//        pict.data[1] = vp->bmp->pixels[2];
//        pict.data[2] = vp->bmp->pixels[1];
//        
//        pict.linesize[0] = vp->bmp->pitches[0];
//        pict.linesize[1] = vp->bmp->pitches[2];
//        pict.linesize[2] = vp->bmp->pitches[1];
        
        // Convert the image into YUV format that SDL uses
        sws_scale
        (
         is->sws_ctx,
         (uint8_t const * const *)pFrame->data,
         pFrame->linesize,
         0,
         is->video_st->codec->height,
         vp->rawdata->data,
         vp->rawdata->linesize
         );
//        SDL_Rect rect;
//        rect.x = 0;
//        rect.y = 0;
//        rect.w = vp->width;
//        rect.h = vp->height;
        //printf("%d,%d\n",rect.w,rect.h);
        
        //SDL_UpdateTexture( vp->texture, &rect, pFrameYUV->data[0], pFrameYUV->linesize[0] );
        
        //av_free(pFrameYUV);
        
        //SDL_UnlockYUVOverlay(vp->bmp);
        /* now we inform our display thread that we have a pic ready */
        if(++is->pictq_windex == VIDEO_PICTURE_QUEUE_SIZE) {
            is->pictq_windex = 0;
        }
        SDL_LockMutex(is->pictq_mutex);
        is->pictq_size++;
        SDL_UnlockMutex(is->pictq_mutex);
    }
    return 0;
}

int video_thread(void *arg) {
    VideoState *is = (VideoState *)arg;
    AVPacket pkt1, *packet = &pkt1;
    int frameFinished;
    AVFrame *pFrame;
    
    pFrame = avcodec_alloc_frame();
    
    for(;;) {
        if(packet_queue_get(&is->videoq, packet, 1) < 0) {
            // means we quit getting packets
            break;
        }
        // Decode video frame
        avcodec_decode_video2(is->video_st->codec, pFrame, &frameFinished,
                              packet);
        
        // Did we get a video frame?
        if(frameFinished) {
            //printf("video_thread\n");
            if(queue_picture(is, pFrame) < 0) {
                break;
            }
        }
        av_free_packet(packet);
    }
    av_free(pFrame);
    return 0;
}

int stream_component_open(VideoState *is, int stream_index) {
    
    AVFormatContext *pFormatCtx = is->pFormatCtx;
    AVCodecContext *codecCtx = NULL;
    AVCodec *codec = NULL;
    AVDictionary *optionsDict = NULL;
    SDL_AudioSpec wanted_spec, spec;
    
    if(stream_index < 0 || stream_index >= pFormatCtx->nb_streams) {
        return -1;
    }
    
    // Get a pointer to the codec context for the video stream
    codecCtx = pFormatCtx->streams[stream_index]->codec;
    
    if(codecCtx->codec_type == AVMEDIA_TYPE_AUDIO) {
        // Set audio settings from codec info
        wanted_spec.freq = codecCtx->sample_rate;
        wanted_spec.format = AUDIO_S16SYS;
        wanted_spec.channels = codecCtx->channels;
        wanted_spec.silence = 0;
        wanted_spec.samples = SDL_AUDIO_BUFFER_SIZE;
        wanted_spec.callback = audio_callback;
        wanted_spec.userdata = is;
        
        if(SDL_OpenAudio(&wanted_spec, &spec) < 0) {
            fprintf(stderr, "SDL_OpenAudio: %s\n", SDL_GetError());
            return -1;
        }
    }
    codec = avcodec_find_decoder(codecCtx->codec_id);
    if(!codec || (avcodec_open2(codecCtx, codec, &optionsDict) < 0)) {
        fprintf(stderr, "Unsupported codec!\n");
        return -1;
    }
    
    switch(codecCtx->codec_type) {
        case AVMEDIA_TYPE_AUDIO:
            is->audioStream = stream_index;
            is->audio_st = pFormatCtx->streams[stream_index];
            is->audio_buf_size = 0;
            is->audio_buf_index = 0;
            memset(&is->audio_pkt, 0, sizeof(is->audio_pkt));
            packet_queue_init(&is->audioq);
            SDL_PauseAudio(0);
            break;
        case AVMEDIA_TYPE_VIDEO:
            is->videoStream = stream_index;
            is->video_st = pFormatCtx->streams[stream_index];
            
            packet_queue_init(&is->videoq);
            is->video_tid = SDL_CreateThread(video_thread, "video_thread",is);
            is->sws_ctx =
            sws_getContext
            (
             is->video_st->codec->width,
             is->video_st->codec->height,
             is->video_st->codec->pix_fmt,
             is->video_st->codec->width,
             is->video_st->codec->height,
             PIX_FMT_YUV420P,
             SWS_BILINEAR,
             NULL,
             NULL,
             NULL
             );
            break;
        default:
            break;
    }
    return 0;
}

int decode_interrupt_cb(void *opaque) {
    return (global_video_state && global_video_state->quit);
}

int decode_thread(void *arg) {
    
    VideoState *is = (VideoState *)arg;
    AVFormatContext *pFormatCtx = NULL;
    AVPacket pkt1, *packet = &pkt1;
    
    int video_index = -1;
    int audio_index = -1;
    int i;
    
    AVDictionary *io_dict = NULL;
    AVIOInterruptCB callback;
    
    is->videoStream=-1;
    is->audioStream=-1;
    
    global_video_state = is;
    // will interrupt blocking functions if we quit!
    callback.callback = decode_interrupt_cb;
    callback.opaque = is;
    if (avio_open2(&is->io_context, is->filename, 0, &callback, &io_dict))
    {
        fprintf(stderr, "Unable to open I/O for %s\n", is->filename);
        return -1;
    }
    
    // Open video file
    if(avformat_open_input(&pFormatCtx, is->filename, NULL, NULL)!=0)
        return -1; // Couldn't open file
    
    is->pFormatCtx = pFormatCtx;
    
    // Retrieve stream information
    if(avformat_find_stream_info(pFormatCtx, NULL)<0)
        return -1; // Couldn't find stream information
    
    // Dump information about file onto standard error
    av_dump_format(pFormatCtx, 0, is->filename, 0);
    
    // Find the first video stream
    
    for(i=0; i<pFormatCtx->nb_streams; i++) {
        if(pFormatCtx->streams[i]->codec->codec_type==AVMEDIA_TYPE_VIDEO &&
           video_index < 0) {
            video_index=i;
        }
        if(pFormatCtx->streams[i]->codec->codec_type==AVMEDIA_TYPE_AUDIO &&
           audio_index < 0) {
            audio_index=i;
        }
    }
    if(audio_index >= 0) {
        stream_component_open(is, audio_index);
    }
    if(video_index >= 0) {
        stream_component_open(is, video_index);
    }
    
    if(is->videoStream < 0 || is->audioStream < 0) {
        fprintf(stderr, "%s: could not open codecs\n", is->filename);
        goto fail;
    }
    
    // main decode loop
    
    for(;;) {
        if(is->quit) {
            break;
        }
        // seek stuff goes here
        if(is->audioq.size > MAX_AUDIOQ_SIZE ||
           is->videoq.size > MAX_VIDEOQ_SIZE) {
            SDL_Delay(10);
            continue;
        }
        if(av_read_frame(is->pFormatCtx, packet) < 0) {
            if(is->pFormatCtx->pb->error == 0) {
                SDL_Delay(100); /* no error; wait for user input */
                continue;
            } else {
                break;
            }
        }
        // Is this a packet from the video stream?
        if(packet->stream_index == is->videoStream) {
            packet_queue_put(&is->videoq, packet);
        } else if(packet->stream_index == is->audioStream) {
            packet_queue_put(&is->audioq, packet);
        } else {
            av_free_packet(packet);
        }
    }
    /* all done - wait for it */
    while(!is->quit) {
        SDL_Delay(100);
    }
    
fail:
    if(1){
        SDL_Event event;
        event.type = FF_QUIT_EVENT;
        event.user.data1 = is;
        SDL_PushEvent(&event);
    }
    return 0;
}

int main(int argc, char *argv[]) {
    
    SDL_Event       event;
    
    VideoState      *is;
    
    struct SDL_Window     *pScreen;
    struct SDL_Renderer   *pRenderer;
    
    
    is = av_mallocz(sizeof(VideoState));
    
    if(argc < 2) {
        fprintf(stderr, "Usage: test <file>\n");
        exit(1);
    }
    // Register all formats and codecs
    av_register_all();
    
    if(SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_TIMER)) {
        fprintf(stderr, "Could not initialize SDL - %s\n", SDL_GetError());
        exit(1);
    }
    
    // Make a screen to put our video
//#ifndef __DARWIN__
//    screen = SDL_SetVideoMode(640, 480, 0, 0);
//#else
//    screen = SDL_SetVideoMode(640, 480, 24, 0);
//#endif
    
    pScreen = SDL_CreateWindow("audio & video", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 672,376, SDL_WINDOW_OPENGL);
    
    if(!pScreen) {
        fprintf(stderr, "SDL: could not set video mode - exiting\n");
        exit(1);
    }
    //SDL_Window *windows = pScreen;
    
    //pScreen->windowed;
    pRenderer = SDL_CreateRenderer(pScreen, -1, 0);
    
    SDL_Texture* texture = SDL_CreateTexture(pRenderer, SDL_PIXELFORMAT_IYUV, SDL_TEXTUREACCESS_STREAMING, 672, 376);
    
    
    av_strlcpy(is->filename, argv[1], 1024);
    
    is->pictq_mutex = SDL_CreateMutex();
    is->pictq_cond = SDL_CreateCond();
    
    schedule_refresh(is, 40);
    
    is->parse_tid = SDL_CreateThread(decode_thread,"parse_thread", is);
    if(!is->parse_tid) {
        av_free(is);
        return -1;
    }
    for(;;) {
        
        SDL_WaitEvent(&event);
        switch(event.type) {
            case FF_QUIT_EVENT:
            case SDL_QUIT:
                is->quit = 1;
                /*
                 * If the video has finished playing, then both the picture and
                 * audio queues are waiting for more data.  Make them stop
                 * waiting and terminate normally.
                 */
                SDL_CondSignal(is->audioq.cond);
                SDL_CondSignal(is->videoq.cond);
                SDL_Quit();
                return 0;
                break;
            case FF_ALLOC_EVENT:
                alloc_picture(event.user.data1,pRenderer);
                break;
            case FF_REFRESH_EVENT:
                video_refresh_timer(event.user.data1,pRenderer,texture);
                break;
            default:
                break;
        }
    }
    
    SDL_DestroyTexture(texture);
    
    return 0;
    
}

这段代码的总体思路是跑一个parse线程解包，当解析到音频包时放入音频队列，当解析到视频包时放入视频队列，

当接到有视频包后，起一个线程用来解码视频包，解码完调用事件让主线程显示解码完的数据包

注意点

opengl相关操作需要在主线程中进行，比如SDL_UpdateTexture函数。

在我修改int queue_picture(VideoState *is,AVFrame *pFrame)代码时，误将SDL_Texure在此函数中写入数据

导致程序运行到SDL_UpdateTexture( vp->texture, &rect, pFrameYUV->data[0], pFrameYUV->linesize[0] );

后renderdata->glEnable(data->type);处报错，报bad_access，起先以为是pFrameYUV为空指针，后四处排查也找不到原因

突然想起opengl的操作是不是需要在主线程中进行？

后来我将SDL_UpdateTexture操作放置到video_display函数中，问题解决。

运行结果

引用库如下

结束语

2013年最后半小时了，本命年还算顺利

可喜的是这一年技术接触面很广，学会了ios开发，android水平有进阶，c/c++水平有提高，设计模式提高不少

可悲的是阿里前端实习被刷（死的很惨），论文毫无进展，老板要我搞云计算

最后感谢朱阿姝同学的陪伴

希望明年可以顺利完成论文，在github上多贡献几个项目攒人品，父母身体健康