播放器实战--音视频同步方案

#include <stdio.h>
#include <assert.h>
#include <math.h>
#include <SDL.h>
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#include <libswscale/swscale.h>
#include <libswresample/swresample.h>
// compatibility with newer API
#if LIBAVCODEC_VERSION_INT < AV_VERSION_INT(55,28,1)
#define av_frame_alloc avcodec_alloc_frame
#define av_frame_free avcodec_free_frame
#endif
#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 AV_SYNC_THRESHOLD 0.01
#define AV_NOSYNC_THRESHOLD 10.0
#define FF_REFRESH_EVENT (SDL_USEREVENT)
#define FF_QUIT_EVENT (SDL_USEREVENT + 1)
#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 {
  AVPicture *bmp;
  int width, height; /* source height & width */
  int allocated;
  double pts;
} VideoPicture;
typedef struct VideoState {
  AVFormatContext *pFormatCtx;
  int             videoStream, audioStream;
  AVStream        *audio_st;
  AVCodecContext  *audio_ctx;
  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;
  int             audio_hw_buf_size;  
  struct SwrContext *audio_swr_ctx;
  double          audio_clock;
  double          video_clock; ///<pts of last decoded frame / predicted pts of next decoded frame
  double          frame_timer;
  double          frame_last_pts;
  double          frame_last_delay;
  AVStream        *video_st;
  AVCodecContext  *video_ctx;
  PacketQueue     videoq;
  struct SwsContext *video_sws_ctx;
  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;
} VideoState;
SDL_mutex       *text_mutex;
SDL_Window  *win;
SDL_Renderer  *renderer;
SDL_Texture   *texture;
/* 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;
}
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;
}
double get_audio_clock(VideoState *is) {
  double pts;
  int hw_buf_size, bytes_per_sec, n;
  pts = is->audio_clock; /* maintained in the audio thread */
  hw_buf_size = is->audio_buf_size - is->audio_buf_index;
  bytes_per_sec = 0;
  n = is->audio_ctx->channels * 2;
  if(is->audio_st) {
    bytes_per_sec = is->audio_ctx->sample_rate * n;
  }
  if(bytes_per_sec) {
    pts -= (double)hw_buf_size / bytes_per_sec;
  }
  return pts;
}
int audio_decode_frame(VideoState *is, uint8_t *audio_buf, int buf_size, double *pts_ptr) {
  int len1, data_size = 0;
  AVPacket *pkt = &is->audio_pkt;
  double pts;
  int n;
  for(;;) {
    while(is->audio_pkt_size > 0) {
      int got_frame = 0;
      len1 = avcodec_decode_audio4(is->audio_ctx, &is->audio_frame, &got_frame, pkt);
      if(len1 < 0) {
  /* if error, skip frame */
  is->audio_pkt_size = 0;
  break;
      }
      data_size = 0;
      if(got_frame) {
  /*
  data_size = av_samples_get_buffer_size(NULL, 
                 is->audio_ctx->channels,
                 is->audio_frame.nb_samples,
                 is->audio_ctx->sample_fmt,
                 1);
  */
  data_size = 2 * is->audio_frame.nb_samples * 2;
  assert(data_size <= buf_size);
        swr_convert(is->audio_swr_ctx,
                        &audio_buf,
                        MAX_AUDIO_FRAME_SIZE*3/2,
                        (const uint8_t **)is->audio_frame.data,
                        is->audio_frame.nb_samples);
  //memcpy(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;
      }
      pts = is->audio_clock;
      *pts_ptr = pts;
      n = 2 * is->audio_ctx->channels;
      is->audio_clock += (double)data_size /
  (double)(n * is->audio_ctx->sample_rate);
      /* 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;
    /* if update, update the audio clock w/pts */
    if(pkt->pts != AV_NOPTS_VALUE) {
      is->audio_clock = av_q2d(is->audio_st->time_base)*pkt->pts;
    }
  }
}
void audio_callback(void *userdata, Uint8 *stream, int len) {
  VideoState *is = (VideoState *)userdata;
  int len1, audio_size;
  double pts;
  SDL_memset(stream, 0, len);
  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, is->audio_buf, sizeof(is->audio_buf), &pts);
      if(audio_size < 0) {
  /* If error, output silence */
  is->audio_buf_size = 1024 * 2 * 2;
  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;
    SDL_MixAudio(stream,(uint8_t *)is->audio_buf + is->audio_buf_index, len1, SDL_MIX_MAXVOLUME);
    //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_Rect rect;
  VideoPicture *vp;
  float aspect_ratio;
  int w, h, x, y;
  int i;
  vp = &is->pictq[is->pictq_rindex];
  if(vp->bmp) {
    SDL_UpdateYUVTexture( texture, NULL,
                          vp->bmp->data[0], vp->bmp->linesize[0],
                          vp->bmp->data[1], vp->bmp->linesize[1],
                          vp->bmp->data[2], vp->bmp->linesize[2]);
    rect.x = 0;
    rect.y = 0;
    rect.w = is->video_ctx->width;
    rect.h = is->video_ctx->height;
    SDL_LockMutex(text_mutex);
    SDL_RenderClear( renderer );
    SDL_RenderCopy( renderer, texture, NULL, &rect);
    SDL_RenderPresent( renderer );
    SDL_UnlockMutex(text_mutex);
  }
}
void video_refresh_timer(void *userdata) {
  VideoState *is = (VideoState *)userdata;
  VideoPicture *vp;
  double actual_delay, delay, sync_threshold, ref_clock, diff;
  if(is->video_st) {
    if(is->pictq_size == 0) {
      schedule_refresh(is, 1);
    } else {
      vp = &is->pictq[is->pictq_rindex];
      delay = vp->pts - is->frame_last_pts; /* the pts from last time */
      if(delay <= 0 || delay >= 1.0) {
  /* if incorrect delay, use previous one */
  delay = is->frame_last_delay;
      }
      /* save for next time */
      is->frame_last_delay = delay;
      is->frame_last_pts = vp->pts;
      /* update delay to sync to audio */
      ref_clock = get_audio_clock(is);
      diff = vp->pts - ref_clock;
      /* Skip or repeat the frame. Take delay into account
   FFPlay still doesn't "know if this is the best guess." */
      sync_threshold = (delay > AV_SYNC_THRESHOLD) ? delay : AV_SYNC_THRESHOLD;
      if(fabs(diff) < AV_NOSYNC_THRESHOLD) {
  if(diff <= -sync_threshold) {
    delay = 0;
  } else if(diff >= sync_threshold) {
    delay = 2 * delay;
  }
      }
      is->frame_timer += delay;
      /* computer the REAL delay */
      actual_delay = is->frame_timer - (av_gettime() / 1000000.0);
      if(actual_delay < 0.010) {
  /* Really it should skip the picture instead */
  actual_delay = 0.010;
      }
      schedule_refresh(is, (int)(actual_delay * 1000 + 0.5));
      /* show the picture! */
      video_display(is);
      /* 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) {
  int ret = -1;
  VideoState *is = (VideoState *)userdata;
  VideoPicture *vp;
  vp = &is->pictq[is->pictq_windex];
  if(vp->bmp) {
    // we already have one make another, bigger/smaller
    avpicture_free(vp->bmp);
    free(vp->bmp);
    vp->bmp = NULL;
  }
  // Allocate a place to put our YUV image on that screen
  SDL_LockMutex(text_mutex);
  vp->bmp = (AVPicture*)malloc(sizeof(AVPicture));
  ret = avpicture_alloc(vp->bmp, AV_PIX_FMT_YUV420P, is->video_ctx->width, is->video_ctx->height);
  if (ret < 0) {
      fprintf(stderr, "Could not allocate temporary picture: %s\n", av_err2str(ret));
  }
  SDL_UnlockMutex(text_mutex);
  vp->width = is->video_ctx->width;
  vp->height = is->video_ctx->height;
  vp->allocated = 1;
}
int queue_picture(VideoState *is, AVFrame *pFrame, double pts) {
  VideoPicture *vp;
  /* 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->bmp ||
     vp->width != is->video_ctx->width ||
     vp->height != is->video_ctx->height) {
    vp->allocated = 0;
    alloc_picture(is);
    if(is->quit) {
      return -1;
    }
  }
  /* We have a place to put our picture on the queue */
  if(vp->bmp) {
    vp->pts = pts;
    // Convert the image into YUV format that SDL uses
    sws_scale(is->video_sws_ctx, (uint8_t const * const *)pFrame->data,
        pFrame->linesize, 0, is->video_ctx->height,
        vp->bmp->data, vp->bmp->linesize);
    /* 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;
}
double synchronize_video(VideoState *is, AVFrame *src_frame, double pts) {
  double frame_delay;
  if(pts != 0) {
    /* if we have pts, set video clock to it */
    is->video_clock = pts;
  } else {
    /* if we aren't given a pts, set it to the clock */
    pts = is->video_clock;
  }
  /* update the video clock */
  frame_delay = av_q2d(is->video_ctx->time_base);
  /* if we are repeating a frame, adjust clock accordingly */
  frame_delay += src_frame->repeat_pict * (frame_delay * 0.5);
  is->video_clock += frame_delay;
  return pts;
}
int decode_video_thread(void *arg) {
  VideoState *is = (VideoState *)arg;
  AVPacket pkt1, *packet = &pkt1;
  int frameFinished;
  AVFrame *pFrame;
  double pts;
  pFrame = av_frame_alloc();
  for(;;) {
    if(packet_queue_get(&is->videoq, packet, 1) < 0) {
      // means we quit getting packets
      break;
    }
    pts = 0;
    // Decode video frame
    avcodec_decode_video2(is->video_ctx, pFrame, &frameFinished, packet);
    if((pts = av_frame_get_best_effort_timestamp(pFrame)) == AV_NOPTS_VALUE) {
      pts = 0;
    }
    pts *= av_q2d(is->video_st->time_base);
    // Did we get a video frame?
    if(frameFinished) {
      pts = synchronize_video(is, pFrame, pts);
      if(queue_picture(is, pFrame, pts) < 0) {
  break;
      }
    }
    av_free_packet(packet);
  }
  av_frame_free(&pFrame);
  return 0;
}
int stream_component_open(VideoState *is, int stream_index) {
  AVFormatContext *pFormatCtx = is->pFormatCtx;
  AVCodecContext *codecCtx = NULL;
  AVCodec *codec = NULL;
  SDL_AudioSpec wanted_spec, spec;
  if(stream_index < 0 || stream_index >= pFormatCtx->nb_streams) {
    return -1;
  }
  codecCtx = avcodec_alloc_context3(NULL);
  int ret = avcodec_parameters_to_context(codecCtx, pFormatCtx->streams[stream_index]->codecpar);
  if (ret < 0)
    return -1;
  codec = avcodec_find_decoder(codecCtx->codec_id);
  if(!codec) {
    fprintf(stderr, "Unsupported codec!\n");
    return -1;
  }
  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 = 2;//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;
    }
    is->audio_hw_buf_size = spec.size;
  }
  if(avcodec_open2(codecCtx, codec, NULL) < 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_ctx = codecCtx;
    is->audio_buf_size = 0;
    is->audio_buf_index = 0;
    memset(&is->audio_pkt, 0, sizeof(is->audio_pkt));
    packet_queue_init(&is->audioq);
    //Out Audio Param
    uint64_t out_channel_layout=AV_CH_LAYOUT_STEREO;
    //AAC:1024  MP3:1152
    int out_nb_samples= is->audio_ctx->frame_size;
    //AVSampleFormat out_sample_fmt = AV_SAMPLE_FMT_S16;
    int out_sample_rate=is->audio_ctx->sample_rate;
    int out_channels=av_get_channel_layout_nb_channels(out_channel_layout);
    //Out Buffer Size
    /*
    int out_buffer_size=av_samples_get_buffer_size(NULL,
                                                   out_channels,
                                                   out_nb_samples,
                                                   AV_SAMPLE_FMT_S16,
                                                   1);
                                                   */
    //uint8_t *out_buffer=(uint8_t *)av_malloc(MAX_AUDIO_FRAME_SIZE*2);
    int64_t in_channel_layout=av_get_default_channel_layout(is->audio_ctx->channels);
    struct SwrContext *audio_convert_ctx;
    audio_convert_ctx = swr_alloc();
    swr_alloc_set_opts(audio_convert_ctx,
                       out_channel_layout,
                       AV_SAMPLE_FMT_S16,
                       out_sample_rate,
                       in_channel_layout,
                       is->audio_ctx->sample_fmt,
                       is->audio_ctx->sample_rate,
                       0,
                       NULL);
    fprintf(stderr, "swr opts: out_channel_layout:%lld, out_sample_fmt:%d, out_sample_rate:%d, in_channel_layout:%lld, in_sample_fmt:%d, in_sample_rate:%d",
            out_channel_layout, AV_SAMPLE_FMT_S16, out_sample_rate, in_channel_layout, is->audio_ctx->sample_fmt, is->audio_ctx->sample_rate);
    swr_init(audio_convert_ctx);
    is->audio_swr_ctx = audio_convert_ctx;
    SDL_PauseAudio(0);
    break;
  case AVMEDIA_TYPE_VIDEO:
    is->videoStream = stream_index;
    is->video_st = pFormatCtx->streams[stream_index];
    is->video_ctx = codecCtx;
    is->frame_timer = (double)av_gettime() / 1000000.0;
    is->frame_last_delay = 40e-3;
    packet_queue_init(&is->videoq);
    is->video_sws_ctx = sws_getContext(is->video_ctx->width, is->video_ctx->height,
         is->video_ctx->pix_fmt, is->video_ctx->width,
         is->video_ctx->height, AV_PIX_FMT_YUV420P,
         SWS_BILINEAR, NULL, NULL, NULL
         );
    is->video_tid = SDL_CreateThread(decode_video_thread, "decode_video_thread", is);
    break;
  default:
    break;
  }
}
int demux_thread(void *arg) {
  Uint32 pixformat;
  VideoState *is = (VideoState *)arg;
  AVFormatContext *pFormatCtx;
  AVPacket pkt1, *packet = &pkt1;
  int video_index = -1;
  int audio_index = -1;
  int i;
  is->videoStream=-1;
  is->audioStream=-1;
  global_video_state = is;
  // 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;
  }
  win = SDL_CreateWindow("Media Player",
           SDL_WINDOWPOS_UNDEFINED,
       SDL_WINDOWPOS_UNDEFINED,
       is->video_ctx->width, is->video_ctx->height,
       SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE);
  renderer = SDL_CreateRenderer(win, -1, 0);
  pixformat = SDL_PIXELFORMAT_IYUV;
  texture = SDL_CreateTexture(renderer,
            pixformat, 
            SDL_TEXTUREACCESS_STREAMING,
            is->video_ctx->width,
            is->video_ctx->height);
  // main decode loop
  for(;;) {
    if(is->quit) {
      SDL_CondSignal(is->videoq.cond);
      SDL_CondSignal(is->audioq.cond);
      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[]) {
  int             ret = -1;
  SDL_Event       event;
  VideoState      *is;
  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);
  }
  text_mutex = SDL_CreateMutex();
  av_strlcpy(is->filename, argv[1], sizeof(is->filename));
  is->pictq_mutex = SDL_CreateMutex();
  is->pictq_cond = SDL_CreateCond();
  schedule_refresh(is, 40);
  is->parse_tid = SDL_CreateThread(demux_thread, "demux_thread", is);
  if(!is->parse_tid) {
    av_free(is);
    goto __FAIL;
  }
  for(;;) {
    SDL_WaitEvent(&event);
    switch(event.type) {
    case FF_QUIT_EVENT:
    case SDL_QUIT:
      is->quit = 1;
      //SDL_Quit();
      //return 0;
      goto __QUIT;
      break;
    case FF_REFRESH_EVENT:
      video_refresh_timer(event.user.data1);
      break;
    default:
      break;
    }
  }
__QUIT:
  ret = 0;
__FAIL:
  SDL_Quit();
  /*
  if(audiofd){
    fclose(audiofd);
  }
  if(audiofd1){
    fclose(audiofd1);
  }
  */
  return ret;
}