A/V sync as SDL does not have hardware buffer fullness info. */
#define SDL_AUDIO_BUFFER_SIZE 1024
-/* no AV sync correction is done if below the AV sync threshold */
-#define AV_SYNC_THRESHOLD 0.01
+/* no AV sync correction is done if below the minimum AV sync threshold */
+#define AV_SYNC_THRESHOLD_MIN 0.01
+/* AV sync correction is done if above the maximum AV sync threshold */
+#define AV_SYNC_THRESHOLD_MAX 0.1
+/* If a frame duration is longer than this, it will not be duplicated to compensate AV sync */
+#define AV_SYNC_FRAMEDUP_THRESHOLD 0.1
/* no AV correction is done if too big error */
#define AV_NOSYNC_THRESHOLD 10.0
/* skip or repeat frame. We take into account the
delay to compute the threshold. I still don't know
if it is the best guess */
- sync_threshold = FFMAX(AV_SYNC_THRESHOLD, delay);
- if (!isnan(diff) && fabs(diff) < AV_NOSYNC_THRESHOLD) {
+ sync_threshold = FFMAX(AV_SYNC_THRESHOLD_MIN, FFMIN(AV_SYNC_THRESHOLD_MAX, delay));
+ if (!isnan(diff) && fabs(diff) < is->max_frame_duration) {
if (diff <= -sync_threshold)
- delay = 0;
+ delay = FFMAX(0, delay + diff);
+ else if (diff >= sync_threshold && delay > AV_SYNC_FRAMEDUP_THRESHOLD)
+ delay = delay + diff;
else if (diff >= sync_threshold)
delay = 2 * delay;
}