From d60927b676bfd7fadee607281935529dd3fdf82c Mon Sep 17 00:00:00 2001 From: Romane Lafon Date: Mon, 12 Oct 2020 19:01:17 +0200 Subject: [PATCH] avfilter/avf_aphasemeter: add out of phase and mono detection Extend aphasemeter to detect out of phase or mono sequences in stereo streams. Signed-off-by: Romane Lafon --- doc/filters.texi | 33 ++++++++++ libavfilter/avf_aphasemeter.c | 118 +++++++++++++++++++++++++++++++++- 2 files changed, 150 insertions(+), 1 deletion(-) diff --git a/doc/filters.texi b/doc/filters.texi index 037a37be23..809761a43e 100644 --- a/doc/filters.texi +++ b/doc/filters.texi @@ -23356,6 +23356,39 @@ Set color which will be used for drawing median phase. If color is Enable video output. Default is enabled. @end table +@subsection phasing detection + +The filter also detects out of phase and mono sequences in stereo streams. +It logs the sequence start, end and duration when it lasts longer or as long as the minimum set. + +The filter accepts the following options for this detection: + +@table @option +@item phasing +Enable mono and out of phase detection. Default is disabled. + +@item tolerance, t +Set phase tolerance for mono detection, in amplitude ratio. Default is @code{0}. +Allowed range is @code{[0, 1]}. + +@item angle, a +Set angle threshold for out of phase detection, in degree. Default is @code{170}. +Allowed range is @code{[90, 180]}. + +@item duration, d +Set mono or out of phase duration until notification, expressed in seconds. Default is @code{2}. +@end table + +@subsection Examples + +@itemize +@item +Complete example with @command{ffmpeg} to detect 1 second of mono with 0.001 phase tolerance: +@example +ffmpeg -i stereo.wav -af aphasemeter=video=0:phasing=1:duration=1:tolerance=0.001 -f null - +@end example +@end itemize + @section avectorscope Convert input audio to a video output, representing the audio vector diff --git a/libavfilter/avf_aphasemeter.c b/libavfilter/avf_aphasemeter.c index 31fc8b1b3f..61da9a90b6 100644 --- a/libavfilter/avf_aphasemeter.c +++ b/libavfilter/avf_aphasemeter.c @@ -28,26 +28,43 @@ #include "libavutil/intreadwrite.h" #include "libavutil/opt.h" #include "libavutil/parseutils.h" +#include "libavutil/timestamp.h" #include "avfilter.h" #include "formats.h" #include "audio.h" #include "video.h" #include "internal.h" +#include "float.h" typedef struct AudioPhaseMeterContext { const AVClass *class; AVFrame *out; int do_video; + int do_phasing_detection; int w, h; AVRational frame_rate; int contrast[4]; uint8_t *mpc_str; uint8_t mpc[4]; int draw_median_phase; + int is_mono; + int is_out_phase; + int start_mono_presence; + int start_out_phase_presence; + float tolerance; + float angle; + float phase; + AVRational time_base; + int64_t duration; + int64_t frame_end; + int64_t mono_idx[2]; + int64_t out_phase_idx[2]; } AudioPhaseMeterContext; +#define MAX_DURATION (24*60*60*1000000LL) #define OFFSET(x) offsetof(AudioPhaseMeterContext, x) #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM +#define get_duration(index) (index[1] - index[0]) static const AVOption aphasemeter_options[] = { { "rate", "set video rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"}, 0, INT_MAX, FLAGS }, @@ -59,6 +76,13 @@ static const AVOption aphasemeter_options[] = { { "bc", "set blue contrast", OFFSET(contrast[2]), AV_OPT_TYPE_INT, {.i64=1}, 0, 255, FLAGS }, { "mpc", "set median phase color", OFFSET(mpc_str), AV_OPT_TYPE_STRING, {.str = "none"}, 0, 0, FLAGS }, { "video", "set video output", OFFSET(do_video), AV_OPT_TYPE_BOOL, {.i64 = 1}, 0, 1, FLAGS }, + { "phasing", "set mono and out-of-phase detection output", OFFSET(do_phasing_detection), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, FLAGS }, + { "tolerance", "set phase tolerance for mono detection", OFFSET(tolerance), AV_OPT_TYPE_FLOAT, {.dbl = 0.}, 0, 1, FLAGS }, + { "t", "set phase tolerance for mono detection", OFFSET(tolerance), AV_OPT_TYPE_FLOAT, {.dbl = 0.}, 0, 1, FLAGS }, + { "angle", "set angle threshold for out-of-phase detection", OFFSET(angle), AV_OPT_TYPE_FLOAT, {.dbl = 170.}, 90, 180, FLAGS }, + { "a", "set angle threshold for out-of-phase detection", OFFSET(angle), AV_OPT_TYPE_FLOAT, {.dbl = 170.}, 90, 180, FLAGS }, + { "duration", "set minimum mono or out-of-phase duration in seconds", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64=2000000}, 0, MAX_DURATION, FLAGS }, + { "d", "set minimum mono or out-of-phase duration in seconds", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64=2000000}, 0, MAX_DURATION, FLAGS }, { NULL } }; @@ -104,6 +128,7 @@ static int config_input(AVFilterLink *inlink) AVFilterContext *ctx = inlink->dst; AudioPhaseMeterContext *s = ctx->priv; int nb_samples; + s->duration = av_rescale(s->duration, inlink->sample_rate, AV_TIME_BASE); if (s->do_video) { nb_samples = FFMAX(1, av_rescale(inlink->sample_rate, s->frame_rate.den, s->frame_rate.num)); @@ -140,6 +165,76 @@ static inline int get_x(float phase, int w) return (phase + 1.) / 2. * (w - 1); } +static inline void add_metadata(AVFrame *insamples, const char *key, char *value) +{ + char buf[128]; + + snprintf(buf, sizeof(buf), "lavfi.aphasemeter.%s", key); + av_dict_set(&insamples->metadata, buf, value, 0); +} + +static inline void update_mono_detection(AudioPhaseMeterContext *s, AVFrame *insamples, int mono_measurement) +{ + int64_t mono_duration; + if (!s->is_mono && mono_measurement) { + s->is_mono = 1; + s->start_mono_presence = 1; + s->mono_idx[0] = insamples->pts; + } + if (s->is_mono && mono_measurement && s->start_mono_presence) { + s->mono_idx[1] = s->frame_end; + mono_duration = get_duration(s->mono_idx); + if (mono_duration >= s->duration) { + add_metadata(insamples, "mono_start", av_ts2timestr(s->mono_idx[0], &s->time_base)); + av_log(s, AV_LOG_INFO, "mono_start: %s\n", av_ts2timestr(s->mono_idx[0], &s->time_base)); + s->start_mono_presence = 0; + } + } + if (s->is_mono && !mono_measurement) { + s->mono_idx[1] = insamples ? insamples->pts : s->frame_end; + mono_duration = get_duration(s->mono_idx); + if (mono_duration >= s->duration) { + if (insamples) { + add_metadata(insamples, "mono_end", av_ts2timestr(s->mono_idx[1], &s->time_base)); + add_metadata(insamples, "mono_duration", av_ts2timestr(mono_duration, &s->time_base)); + } + av_log(s, AV_LOG_INFO, "mono_end: %s | mono_duration: %s\n", av_ts2timestr(s->mono_idx[1], &s->time_base), av_ts2timestr(mono_duration, &s->time_base)); + } + s->is_mono = 0; + } +} + +static inline void update_out_phase_detection(AudioPhaseMeterContext *s, AVFrame *insamples, int out_phase_measurement) +{ + int64_t out_phase_duration; + if (!s->is_out_phase && out_phase_measurement) { + s->is_out_phase = 1; + s->start_out_phase_presence = 1; + s->out_phase_idx[0] = insamples->pts; + } + if (s->is_out_phase && out_phase_measurement && s->start_out_phase_presence) { + s->out_phase_idx[1] = s->frame_end; + out_phase_duration = get_duration(s->out_phase_idx); + if (out_phase_duration >= s->duration) { + add_metadata(insamples, "out_phase_start", av_ts2timestr(s->out_phase_idx[0], &s->time_base)); + av_log(s, AV_LOG_INFO, "out_phase_start: %s\n", av_ts2timestr(s->out_phase_idx[0], &s->time_base)); + s->start_out_phase_presence = 0; + } + } + if (s->is_out_phase && !out_phase_measurement) { + s->out_phase_idx[1] = insamples ? insamples->pts : s->frame_end; + out_phase_duration = get_duration(s->out_phase_idx); + if (out_phase_duration >= s->duration) { + if (insamples) { + add_metadata(insamples, "out_phase_end", av_ts2timestr(s->out_phase_idx[1], &s->time_base)); + add_metadata(insamples, "out_phase_duration", av_ts2timestr(out_phase_duration, &s->time_base)); + } + av_log(s, AV_LOG_INFO, "out_phase_end: %s | out_phase_duration: %s\n", av_ts2timestr(s->out_phase_idx[1], &s->time_base), av_ts2timestr(out_phase_duration, &s->time_base)); + } + s->is_out_phase = 0; + } +} + static int filter_frame(AVFilterLink *inlink, AVFrame *in) { AVFilterContext *ctx = inlink->dst; @@ -154,6 +249,10 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *in) AVFrame *out; uint8_t *dst; int i; + int mono_measurement; + int out_phase_measurement; + float tolerance = 1.0f - s->tolerance; + float angle = cosf(s->angle/180.0f*M_PI); if (s->do_video && (!s->out || s->out->width != outlink->w || s->out->height != outlink->h)) { @@ -193,6 +292,7 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *in) fphase += phase; } fphase /= in->nb_samples; + s->phase = fphase; if (s->do_video) { if (s->draw_median_phase) { @@ -209,7 +309,19 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *in) uint8_t value[128]; snprintf(value, sizeof(value), "%f", fphase); - av_dict_set(metadata, "lavfi.aphasemeter.phase", value, 0); + add_metadata(in, "phase", value); + } + + if (s->do_phasing_detection) { + s->time_base = inlink->time_base; + s->frame_end = in->pts + av_rescale_q(in->nb_samples, + (AVRational){ 1, in->sample_rate }, inlink->time_base); + + mono_measurement = (tolerance - fphase) < FLT_EPSILON; + out_phase_measurement = (angle - fphase) > FLT_EPSILON; + + update_mono_detection(s, in, mono_measurement); + update_out_phase_detection(s, in, out_phase_measurement); } if (s->do_video) { @@ -228,6 +340,10 @@ static av_cold void uninit(AVFilterContext *ctx) { AudioPhaseMeterContext *s = ctx->priv; + if (s->do_phasing_detection) { + update_mono_detection(s, NULL, 0); + update_out_phase_detection(s, NULL, 0); + } av_frame_free(&s->out); }