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player: move audio speed adjustment code 

Move it (in a cosmetic sense), and also move its invocation to below all
the video handling.

All other changes remain cosmetic, including moving the framedrop
calculation code, and getting rid of the video_speed_correction
variable.
This commit is contained in:
wm4 2015-11-04 19:37:15 +01:00
parent e3db686e87
commit 8f7cf9443f
1 changed files with 62 additions and 56 deletions
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118
player/video.c
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@ -874,6 +874,46 @@ static bool using_spdif_passthrough(struct MPContext *mpctx)
return false;
}
static void adjust_audio_speed(struct MPContext *mpctx, double vsync)
{
struct MPOpts *opts = mpctx->opts;
int mode = opts->video_sync;
double audio_factor = 1.0;
if (mode == VS_DISP_RESAMPLE && mpctx->audio_status == STATUS_PLAYING) {
// Try to smooth out audio timing drifts. This can happen if either
// video isn't playing at expected speed, or audio is not playing at
// the requested speed. Both are unavoidable.
// The audio desync is made up of 2 parts: 1. drift due to rounding
// errors and imperfect information, and 2. an offset, due to
// unaligned audio/video start, or disruptive events halting audio
// or video for a small time.
// Instead of trying to be clever, just apply an awfully dumb drift
// compensation with a constant factor, which does what we want. In
// theory we could calculate the exact drift compensation needed,
// but it likely would be wrong anyway, and we'd run into the same
// issues again, except with more complex code.
// 1 means drifts to positive, -1 means drifts to negative
double max_drift = vsync / 2;
double av_diff = mpctx->last_av_difference;
int new = mpctx->display_sync_drift_dir;
if (av_diff * -mpctx->display_sync_drift_dir >= 0)
new = 0;
if (fabs(av_diff) > max_drift)
new = av_diff >= 0 ? 1 : -1;
if (mpctx->display_sync_drift_dir != new) {
MP_VERBOSE(mpctx, "Change display sync audio drift: %d\n", new);
mpctx->display_sync_drift_dir = new;
}
double max_correct = opts->sync_max_audio_change / 100;
audio_factor = 1 + max_correct * -mpctx->display_sync_drift_dir;
}
mpctx->speed_factor_a = audio_factor * mpctx->speed_factor_v;
MP_STATS(mpctx, "value %f aspeed", mpctx->speed_factor_a - 1);
}
// Find a speed factor such that the display FPS is an integer multiple of the
// effective video FPS. If this is not possible, try to do it for multiples,
// which still leads to an improved end result.
@ -938,9 +978,11 @@ static void handle_display_sync_frame(struct MPContext *mpctx,
goto done;
}
double video_speed_correction = calc_best_speed(mpctx, vsync, adjusted_duration);
if (video_speed_correction <= 0)
mpctx->speed_factor_v = calc_best_speed(mpctx, vsync, adjusted_duration);
if (mpctx->speed_factor_v <= 0) {
mpctx->speed_factor_v = 1.0;
goto done;
}
double av_diff = mpctx->last_av_difference;
if (fabs(av_diff) > 0.5)
@ -956,6 +998,21 @@ static void handle_display_sync_frame(struct MPContext *mpctx,
mpctx->display_sync_disable_counter = 50;
}
// Determine for how many vsyncs a frame should be displayed. This can be
// e.g. 2 for 30hz on a 60hz display. It can also be 0 if the video
// framerate is higher than the display framerate.
// We use the speed-adjusted (i.e. real) frame duration for this.
double frame_duration = adjusted_duration / mpctx->speed_factor_v;
double ratio = (frame_duration + mpctx->display_sync_error) / vsync;
int num_vsyncs = MPMAX(floor(ratio + 0.5), 0);
double prev_error = mpctx->display_sync_error;
mpctx->display_sync_error += frame_duration - num_vsyncs * vsync;
frame->vsync_offset = mpctx->display_sync_error * 1e6;
MP_DBG(mpctx, "s=%f vsyncs=%d dur=%f ratio=%f err=%.20f (%f)\n",
mpctx->speed_factor_v, num_vsyncs, adjusted_duration, ratio,
mpctx->display_sync_error, mpctx->display_sync_error / vsync);
MP_STATS(mpctx, "value %f avdiff", av_diff);
// Intended number of additional display frames to drop (<0) or repeat (>0)
@ -967,58 +1024,6 @@ static void handle_display_sync_frame(struct MPContext *mpctx,
if (drop && fabs(av_diff) >= 0.080 && fabs(av_diff) / vsync >= 2)
drop_repeat = -av_diff / vsync; // round towards 0
av_diff += drop_repeat * vsync;
if (resample) {
double audio_factor = 1.0;
if (mode == VS_DISP_RESAMPLE && mpctx->audio_status == STATUS_PLAYING) {
// Try to smooth out audio timing drifts. This can happen if either
// video isn't playing at expected speed, or audio is not playing at
// the requested speed. Both are unavoidable.
// The audio desync is made up of 2 parts: 1. drift due to rounding
// errors and imperfect information, and 2. an offset, due to
// unaligned audio/video start, or disruptive events halting audio
// or video for a small time.
// Instead of trying to be clever, just apply an awfully dumb drift
// compensation with a constant factor, which does what we want. In
// theory we could calculate the exact drift compensation needed,
// but it likely would be wrong anyway, and we'd run into the same
// issues again, except with more complex code.
// 1 means drifts to positive, -1 means drifts to negative
double max_drift = vsync / 2;
int new = mpctx->display_sync_drift_dir;
if (av_diff * -mpctx->display_sync_drift_dir >= 0)
new = 0;
if (fabs(av_diff) > max_drift)
new = av_diff >= 0 ? 1 : -1;
if (mpctx->display_sync_drift_dir != new) {
MP_VERBOSE(mpctx, "Change display sync audio drift: %d\n", new);
mpctx->display_sync_drift_dir = new;
}
double max_correct = opts->sync_max_audio_change / 100;
audio_factor = 1 + max_correct * -mpctx->display_sync_drift_dir;
}
mpctx->speed_factor_a = audio_factor * video_speed_correction;
MP_STATS(mpctx, "value %f aspeed", mpctx->speed_factor_a - 1);
}
// Determine for how many vsyncs a frame should be displayed. This can be
// e.g. 2 for 30hz on a 60hz display. It can also be 0 if the video
// framerate is higher than the display framerate.
// We use the speed-adjusted (i.e. real) frame duration for this.
double frame_duration = adjusted_duration / video_speed_correction;
double ratio = (frame_duration + mpctx->display_sync_error) / vsync;
int num_vsyncs = MPMAX(floor(ratio + 0.5), 0);
double prev_error = mpctx->display_sync_error;
mpctx->display_sync_error += frame_duration - num_vsyncs * vsync;
frame->vsync_offset = mpctx->display_sync_error * 1e6;
MP_DBG(mpctx, "s=%f vsyncs=%d dur=%f ratio=%f err=%.20f (%f)\n",
video_speed_correction, num_vsyncs, adjusted_duration, ratio,
mpctx->display_sync_error, mpctx->display_sync_error / vsync);
// We can only drop all frames at most. We can repeat much more frames,
// but we still limit it to 10 times the original frames to avoid that
// corner cases or exceptional situations cause too much havoc.
@ -1042,11 +1047,12 @@ static void handle_display_sync_frame(struct MPContext *mpctx,
mpctx->total_avsync_change = 0;
update_av_diff(mpctx, time_left * opts->playback_speed);
if (resample)
adjust_audio_speed(mpctx, vsync);
// A bad guess, only needed when reverting to audio sync.
mpctx->time_frame = time_left;
mpctx->speed_factor_v = video_speed_correction;
frame->num_vsyncs = num_vsyncs;
frame->display_synced = true;