* overhead
*/
if(!strcmp(oc->oformat->name, "avi")) {
- if ( copy_tb<0 && av_q2d(ist->st->r_frame_rate) >= av_q2d(ist->st->avg_frame_rate)
+ if ( copy_tb<0 && ist->st->r_frame_rate.num
+ && av_q2d(ist->st->r_frame_rate) >= av_q2d(ist->st->avg_frame_rate)
&& 0.5/av_q2d(ist->st->r_frame_rate) > av_q2d(ist->st->time_base)
&& 0.5/av_q2d(ist->st->r_frame_rate) > av_q2d(dec_ctx->time_base)
&& av_q2d(ist->st->time_base) < 1.0/500 && av_q2d(dec_ctx->time_base) < 1.0/500