void avfilter_start_frame(AVFilterLink *link, AVFilterBufferRef *picref) { void (*start_frame)(AVFilterLink *, AVFilterBufferRef *); AVFilterPad *dst = link->dstpad; FF_DPRINTF_START(NULL, start_frame); ff_dprintf_link(NULL, link, 0); dprintf(NULL, " "); ff_dprintf_ref(NULL, picref, 1); if (!(start_frame = dst->start_frame)) start_frame = avfilter_default_start_frame; /* prepare to copy the picture if it has insufficient permissions */ if ((dst->min_perms & picref->perms) != dst->min_perms || dst->rej_perms & picref->perms) { av_log(link->dst, AV_LOG_DEBUG, "frame copy needed (have perms %x, need %x, reject %x)\n", picref->perms, link->dstpad->min_perms, link->dstpad->rej_perms); link->cur_buf = avfilter_get_video_buffer(link, dst->min_perms, link->w, link->h); link->src_buf = picref; avfilter_copy_buffer_ref_props(link->cur_buf, link->src_buf); } else link->cur_buf = picref; start_frame(link, link->cur_buf); }