func: void avfilter_filter_samples(AVFilterLink *link, AVFilterBufferRef *samplesref)
  
  {
  
      void (*filter_samples)(AVFilterLink *, AVFilterBufferRef *);
  
      AVFilterPad *dst = link->dstpad;
  
      int i;
  
  
  
      FF_DPRINTF_START(NULL, filter_samples); ff_dlog_link(NULL, link, 1);
  
  
  
      if (!(filter_samples = dst->filter_samples))
  
          filter_samples = avfilter_default_filter_samples;
  
  
  
      /* prepare to copy the samples if the buffer has insufficient permissions */
  
      if ((dst->min_perms & samplesref->perms) != dst->min_perms ||
  
          dst->rej_perms & samplesref->perms) {
  
  
  
          av_log(link->dst, AV_LOG_DEBUG,
  
                 "Copying audio data in avfilter (have perms %x, need %x, reject %x)\n",
  
                 samplesref->perms, link->dstpad->min_perms, link->dstpad->rej_perms);
  
  
  
          link->cur_buf = avfilter_default_get_audio_buffer(link, dst->min_perms,
  
                                                            samplesref->audio->nb_samples);
  
          link->cur_buf->pts                = samplesref->pts;
  
          link->cur_buf->audio->sample_rate = samplesref->audio->sample_rate;
  
  
  
          /* Copy actual data into new samples buffer */
  
          for (i = 0; samplesref->data[i]; i++)
  
              memcpy(link->cur_buf->data[i], samplesref->data[i], samplesref->linesize[0]);
  
  
  
          avfilter_unref_buffer(samplesref);
  
      } else
  
          link->cur_buf = samplesref;
  
  
  
      filter_samples(link, link->cur_buf);
  
  }
  