+static void init_encoder_time_base(OutputStream *ost, AVRational default_time_base)
+{
+ InputStream *ist = get_input_stream(ost);
+ AVCodecContext *enc_ctx = ost->enc_ctx;
+ AVFormatContext *oc;
+
+ if (ost->enc_timebase.num > 0) {
+ enc_ctx->time_base = ost->enc_timebase;
+ return;
+ }
+
+ if (ost->enc_timebase.num < 0) {
+ if (ist) {
+ enc_ctx->time_base = ist->st->time_base;
+ return;
+ }
+
+ oc = output_files[ost->file_index]->ctx;
+ av_log(oc, AV_LOG_WARNING, "Input stream data not available, using default time base\n");
+ }
+
+ enc_ctx->time_base = default_time_base;
+}
+