static int filter_frame(AVFilterLink *inlink, AVFrame *frame) { AVFilterContext *ctx = inlink->dst; APadContext *apad = ctx->priv; if (apad->whole_len) apad->whole_len -= frame->nb_samples; apad->next_pts = frame->pts + av_rescale_q(frame->nb_samples, (AVRational){1, inlink->sample_rate}, inlink->time_base); return ff_filter_frame(ctx->outputs[0], frame); }