ip/ffmpeg: skip samples only when needed

Gbp-Pq: Name 0004-ip-ffmpeg-skip-samples-only-when-needed.patch

diff --git a/ip/ffmpeg.c b/ip/ffmpeg.c
index ecbf005820dfec959d8776d24688617bd9a40274..5f5a4f37bf540d27738ec3edee4e9dd94ddfef61 100644 (file)
--- a/ip/ffmpeg.c
+++ b/ip/ffmpeg.c
@@ -393,22 +393,26 @@ static int ffmpeg_fill_buffer(struct input_plugin_data *ip_data, AVFormatContext
                                frame_ts = av_rescale_q(frame_ts, st->time_base, AV_TIME_BASE_Q);
                        else
                                frame_ts = input->prev_frame_end;
-                       int64_t frame_dur = av_rescale(frame->nb_samples, AV_TIME_BASE, sf_get_rate(ip_data->sf));
-                       int64_t frame_end = frame_ts + frame_dur;
-                       input->prev_frame_end = frame_end;
-                       d_print("seek_ts: %ld, frame_ts: %ld, frame_end: %ld\n", input->seek_ts, frame_ts, frame_end);
-                       if (frame_end <= input->seek_ts)
-                               continue;
 
-                       /* skip part of this frame */
-                       int64_t skip_samples = av_rescale(input->seek_ts - frame_ts, sf_get_rate(ip_data->sf), AV_TIME_BASE);
-                       in_count -= skip_samples;
-                       if (av_sample_fmt_is_planar(frame->format)) {
-                               for (int i = 0; i < cc->channels; i++) {
-                                       in[i] += skip_samples * sf_get_sample_size(ip_data->sf);
+                       if (frame_ts < input->seek_ts) {
+                               int64_t frame_dur = av_rescale(frame->nb_samples, AV_TIME_BASE, sf_get_rate(ip_data->sf));
+                               int64_t frame_end = frame_ts + frame_dur;
+                               input->prev_frame_end = frame_end;
+                               d_print("seek_ts: %ld, frame_ts: %ld, frame_end: %ld\n", input->seek_ts, frame_ts, frame_end);
+                               if (frame_end <= input->seek_ts)
+                                       continue;
+
+                               /* skip part of this frame */
+                               int64_t skip_samples = av_rescale(input->seek_ts - frame_ts, sf_get_rate(ip_data->sf), AV_TIME_BASE);
+                               in_count -= skip_samples;
+                               if (av_sample_fmt_is_planar(frame->format)) {
+                                       for (int i = 0; i < cc->channels; i++) {
+                                               in[i] += skip_samples * sf_get_sample_size(ip_data->sf);
+                                       }
+                               } else {
+                                       *in += skip_samples * cc->channels * sf_get_sample_size(ip_data->sf);
                                }
-                       } else {
-                               *in += skip_samples * cc->channels * sf_get_sample_size(ip_data->sf);
+                               d_print("skipping %ld samples\n", skip_samples);
                        }
 
                        input->seek_ts = -1;