[Libav-user] avcodec_close() crash

Андрей ashvyrkin at gosniias.ru
Wed Jun 5 12:13:37 CEST 2013


I use to compile the 32-bit version of ffmpeg visual studio 2012. I used 
the latter for now build from 5/29/13.
This is my test code that reproduces the problem:

avcodec_register_all();

     int width = 764, height = 480;
     int got_output;
     AVFrame *frame;
     AVPacket pkt;
     AVCodec *codec;
     AVCodecContext *c = NULL;

     while(1)
     {
         frame = avcodec_alloc_frame();
         if (!frame) {
             fprintf(stderr, "Could not allocate video frame\n");
             return -1;
         }
         frame->format = AV_PIX_FMT_YUV420P;
         frame->width  = width;
         frame->height = height;

         /* the image can be allocated by any means and av_image_alloc() is
          * just the most convenient way if av_malloc() is to be used */
         int ret = av_image_alloc(frame->data, frame->linesize, width, 
height,
                              AV_PIX_FMT_YUV420P, 1);
         if (ret < 0) {
             fprintf(stderr, "Could not allocate raw picture buffer\n");
             av_freep(&frame->data[0]);
             avcodec_free_frame(&frame);
             return -1;
         }

         /* find the mpeg4 video encoder */
         codec = avcodec_find_encoder(AV_CODEC_ID_MPEG4);
         if (!codec) {
             fprintf(stderr, "Codec not found\n");
             return -1;
         }

         c = avcodec_alloc_context3(codec);
         if (!c) {
             fprintf(stderr, "Could not allocate video codec context\n");
             return -1;
         }

         /* put sample parameters */
         c->profile = FF_PROFILE_MPEG4_SIMPLE;
         /* resolution must be a multiple of two */
         c->width = width;
         c->height = height;
         /* frames per second */
         c->time_base.den = 25;
         c->time_base.num = 1;
         c->gop_size = 25; /* emit one intra frame every 25 frames */
         c->pix_fmt = AV_PIX_FMT_YUV420P;
         c->qmax = 4;
         c->qmin = 4;

         /* open it */
         if (avcodec_open2(c, codec, NULL) < 0) {
             fprintf(stderr, "Could not open codec\n");
             avcodec_close(c);
             av_free(c);
             return -1;
         }

         for(int k = 0; k < 30; k++)
         {
             av_init_packet(&pkt);
             pkt.data = NULL;    // packet data will be allocated by the 
encoder
             pkt.size = 0;

             frame->pts = c->frame_number;

             /* encode the image */
             if (avcodec_encode_video2(c, &pkt, frame, &got_output) < 0) {
                 fprintf(stderr, "Error encoding frame\n");
                 return -1;
             }

             if (got_output) {
                 av_free_packet(&pkt);
             }
         }

         if(c)
         {
             avcodec_close(c);
             av_free(c);
         }
         if(frame)
         {
             av_freep(&frame->data[0]);
             avcodec_free_frame(&frame);
         }
     }

When you call function avcodec_close () throws an exception. Such an 
error is detected on the MPEG4 codec with a frame width in the range 
754-767 at an altitude of 480. Perhaps at other resolutions, too. Help 
solve the problem.
...sorry for bad english
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://ffmpeg.org/pipermail/libav-user/attachments/20130605/b1efc2f7/attachment.html>


More information about the Libav-user mailing list