From 6b15874fc2c3f565732201f7907ae1112727d6ae Mon Sep 17 00:00:00 2001 From: Anton Khirnov Date: Thu, 16 Jul 2015 19:26:36 +0200 Subject: af_resample: do not touch the timestamps if we are not resampling This filter currently assumes that the input audio is continuous and does some timestamps manipulation based on this assumption. This is unnecessary if we are only converting the channel layout or the sample format, without resampling. In such a case, just leave the timestamps as they are. --- libavfilter/af_resample.c | 50 +++++++++++++++++++++++++++++------------------ 1 file changed, 31 insertions(+), 19 deletions(-) (limited to 'libavfilter') diff --git a/libavfilter/af_resample.c b/libavfilter/af_resample.c index b125d25d20..62f1d87828 100644 --- a/libavfilter/af_resample.c +++ b/libavfilter/af_resample.c @@ -41,6 +41,7 @@ typedef struct ResampleContext { AVAudioResampleContext *avr; AVDictionary *options; + int resampling; int64_t next_pts; int64_t next_in_pts; @@ -118,6 +119,8 @@ static int config_output(AVFilterLink *outlink) char buf1[64], buf2[64]; int ret; + int64_t resampling_forced; + if (s->avr) { avresample_close(s->avr); avresample_free(&s->avr); @@ -156,9 +159,15 @@ static int config_output(AVFilterLink *outlink) if ((ret = avresample_open(s->avr)) < 0) return ret; - outlink->time_base = (AVRational){ 1, outlink->sample_rate }; - s->next_pts = AV_NOPTS_VALUE; - s->next_in_pts = AV_NOPTS_VALUE; + av_opt_get_int(s->avr, "force_resampling", 0, &resampling_forced); + s->resampling = resampling_forced || (inlink->sample_rate != outlink->sample_rate); + + if (s->resampling) { + outlink->time_base = (AVRational){ 1, outlink->sample_rate }; + s->next_pts = AV_NOPTS_VALUE; + s->next_in_pts = AV_NOPTS_VALUE; + } else + outlink->time_base = inlink->time_base; av_get_channel_layout_string(buf1, sizeof(buf1), -1, inlink ->channel_layout); @@ -241,7 +250,7 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *in) av_assert0(!avresample_available(s->avr)); - if (s->next_pts == AV_NOPTS_VALUE) { + if (s->resampling && s->next_pts == AV_NOPTS_VALUE) { if (in->pts == AV_NOPTS_VALUE) { av_log(ctx, AV_LOG_WARNING, "First timestamp is missing, " "assuming 0.\n"); @@ -260,22 +269,25 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *in) goto fail; } - out->sample_rate = outlink->sample_rate; - /* Only convert in->pts if there is a discontinuous jump. - This ensures that out->pts tracks the number of samples actually - output by the resampler in the absence of such a jump. - Otherwise, the rounding in av_rescale_q() and av_rescale() - causes off-by-1 errors. */ - if (in->pts != AV_NOPTS_VALUE && in->pts != s->next_in_pts) { - out->pts = av_rescale_q(in->pts, inlink->time_base, - outlink->time_base) - - av_rescale(delay, outlink->sample_rate, - inlink->sample_rate); + if (s->resampling) { + out->sample_rate = outlink->sample_rate; + /* Only convert in->pts if there is a discontinuous jump. + This ensures that out->pts tracks the number of samples actually + output by the resampler in the absence of such a jump. + Otherwise, the rounding in av_rescale_q() and av_rescale() + causes off-by-1 errors. */ + if (in->pts != AV_NOPTS_VALUE && in->pts != s->next_in_pts) { + out->pts = av_rescale_q(in->pts, inlink->time_base, + outlink->time_base) - + av_rescale(delay, outlink->sample_rate, + inlink->sample_rate); + } else + out->pts = s->next_pts; + + s->next_pts = out->pts + out->nb_samples; + s->next_in_pts = in->pts + in->nb_samples; } else - out->pts = s->next_pts; - - s->next_pts = out->pts + out->nb_samples; - s->next_in_pts = in->pts + in->nb_samples; + out->pts = in->pts; ret = ff_filter_frame(outlink, out); s->got_output = 1; -- cgit v1.2.3