diff options
author | Paul B Mahol <onemda@gmail.com> | 2020-04-16 16:10:12 +0200 |
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committer | Paul B Mahol <onemda@gmail.com> | 2020-04-17 13:26:30 +0200 |
commit | 87b4fb65a8e89b318a7e3b686a594c3af79f91f0 (patch) | |
tree | 5a66d4f0a13e5320c77195948a1089dfcc103d51 /libavfilter | |
parent | 1b59f3f844dd3fe0dc1a02bc1b602e713e7fde43 (diff) | |
download | ffmpeg-87b4fb65a8e89b318a7e3b686a594c3af79f91f0.tar.gz |
avfilter/af_astats: measure noise floor
Diffstat (limited to 'libavfilter')
-rw-r--r-- | libavfilter/af_astats.c | 80 |
1 files changed, 79 insertions, 1 deletions
diff --git a/libavfilter/af_astats.c b/libavfilter/af_astats.c index 7707f3158d..75ca4f193f 100644 --- a/libavfilter/af_astats.c +++ b/libavfilter/af_astats.c @@ -27,6 +27,9 @@ #include "avfilter.h" #include "internal.h" +#define HISTOGRAM_SIZE 8192 +#define HISTOGRAM_MAX (HISTOGRAM_SIZE-1) + #define MEASURE_ALL UINT_MAX #define MEASURE_NONE 0 @@ -52,6 +55,7 @@ #define MEASURE_NUMBER_OF_NANS (1 << 19) #define MEASURE_NUMBER_OF_INFS (1 << 20) #define MEASURE_NUMBER_OF_DENORMALS (1 << 21) +#define MEASURE_NOISE_FLOOR (1 << 22) #define MEASURE_MINMAXPEAK (MEASURE_MIN_LEVEL | MEASURE_MAX_LEVEL | MEASURE_PEAK_LEVEL) @@ -75,6 +79,11 @@ typedef struct ChannelStats { uint64_t nb_nans; uint64_t nb_infs; uint64_t nb_denormals; + double *win_samples; + unsigned histogram[HISTOGRAM_SIZE]; + int win_pos; + int max_index; + double noise_floor; } ChannelStats; typedef struct AudioStatsContext { @@ -122,6 +131,7 @@ static const AVOption astats_options[] = { { "Dynamic_range" , "", 0, AV_OPT_TYPE_CONST, {.i64=MEASURE_DYNAMIC_RANGE }, 0, 0, FLAGS, "measure" }, { "Zero_crossings" , "", 0, AV_OPT_TYPE_CONST, {.i64=MEASURE_ZERO_CROSSINGS }, 0, 0, FLAGS, "measure" }, { "Zero_crossings_rate" , "", 0, AV_OPT_TYPE_CONST, {.i64=MEASURE_ZERO_CROSSINGS_RATE }, 0, 0, FLAGS, "measure" }, + { "Noise_floor" , "", 0, AV_OPT_TYPE_CONST, {.i64=MEASURE_NOISE_FLOOR }, 0, 0, FLAGS, "measure" }, { "Number_of_samples" , "", 0, AV_OPT_TYPE_CONST, {.i64=MEASURE_NUMBER_OF_SAMPLES }, 0, 0, FLAGS, "measure" }, { "Number_of_NaNs" , "", 0, AV_OPT_TYPE_CONST, {.i64=MEASURE_NUMBER_OF_NANS }, 0, 0, FLAGS, "measure" }, { "Number_of_Infs" , "", 0, AV_OPT_TYPE_CONST, {.i64=MEASURE_NUMBER_OF_INFS }, 0, 0, FLAGS, "measure" }, @@ -197,6 +207,10 @@ static void reset_stats(AudioStatsContext *s) p->nb_infs = 0; p->nb_denormals = 0; p->last = NAN; + p->noise_floor = NAN; + p->win_pos = 0; + memset(p->win_samples, 0, s->tc_samples * sizeof(*p->win_samples)); + memset(p->histogram, 0, sizeof(p->histogram)); } } @@ -207,9 +221,19 @@ static int config_output(AVFilterLink *outlink) s->chstats = av_calloc(sizeof(*s->chstats), outlink->channels); if (!s->chstats) return AVERROR(ENOMEM); + + s->tc_samples = 5 * s->time_constant * outlink->sample_rate + .5; s->nb_channels = outlink->channels; + + for (int i = 0; i < s->nb_channels; i++) { + ChannelStats *p = &s->chstats[i]; + + p->win_samples = av_calloc(s->tc_samples, sizeof(*p->win_samples)); + if (!p->win_samples) + return AVERROR(ENOMEM); + } + s->mult = exp((-1 / s->time_constant / outlink->sample_rate)); - s->tc_samples = 5 * s->time_constant * outlink->sample_rate + .5; s->nb_frames = 0; s->maxbitdepth = av_get_bytes_per_sample(outlink->format) * 8; s->is_double = outlink->format == AV_SAMPLE_FMT_DBL || @@ -249,6 +273,9 @@ static inline void update_minmax(AudioStatsContext *s, ChannelStats *p, double d static inline void update_stat(AudioStatsContext *s, ChannelStats *p, double d, double nd, int64_t i) { + double drop; + int index; + if (d < p->min) { p->min = d; p->nmin = nd; @@ -296,6 +323,38 @@ static inline void update_stat(AudioStatsContext *s, ChannelStats *p, double d, p->mask |= i; p->imask &= i; + drop = p->win_samples[p->win_pos]; + p->win_samples[p->win_pos] = nd; + index = av_clip(FFABS(nd) * HISTOGRAM_MAX, 0, HISTOGRAM_MAX); + p->max_index = FFMAX(p->max_index, index); + p->histogram[index]++; + if (!isnan(p->noise_floor)) + p->histogram[av_clip(FFABS(drop) * HISTOGRAM_MAX, 0, HISTOGRAM_MAX)]--; + p->win_pos++; + + while (p->histogram[p->max_index] == 0) + p->max_index--; + if (p->win_pos >= s->tc_samples || !isnan(p->noise_floor)) { + double noise_floor = 1.; + + for (int i = p->max_index; i >= 0; i--) { + if (p->histogram[i]) { + noise_floor = i / (double)HISTOGRAM_MAX; + break; + } + } + + if (isnan(p->noise_floor)) { + p->noise_floor = noise_floor; + } else { + p->noise_floor = FFMIN(noise_floor, p->noise_floor); + } + } + + if (p->win_pos >= s->tc_samples) { + p->win_pos = 0; + } + if (p->nb_samples >= s->tc_samples) { p->max_sigma_x2 = FFMAX(p->max_sigma_x2, p->avg_sigma_x2); p->min_sigma_x2 = FFMIN(p->min_sigma_x2, p->avg_sigma_x2); @@ -349,6 +408,7 @@ static void set_metadata(AudioStatsContext *s, AVDictionary **metadata) diff1_sum_x2 = 0, sigma_x = 0, sigma_x2 = 0, + noise_floor = 0, min_sigma_x2 = DBL_MAX, max_sigma_x2 =-DBL_MAX; AVRational depth; @@ -372,6 +432,7 @@ static void set_metadata(AudioStatsContext *s, AVDictionary **metadata) max_sigma_x2 = FFMAX(max_sigma_x2, p->max_sigma_x2); sigma_x += p->sigma_x; sigma_x2 += p->sigma_x2; + noise_floor = FFMAX(noise_floor, p->noise_floor); min_count += p->min_count; max_count += p->max_count; min_runs += p->min_runs; @@ -413,6 +474,8 @@ static void set_metadata(AudioStatsContext *s, AVDictionary **metadata) set_meta(metadata, c + 1, "Flat_factor", "%f", LINEAR_TO_DB((p->min_runs + p->max_runs) / (p->min_count + p->max_count))); if (s->measure_perchannel & MEASURE_PEAK_COUNT) set_meta(metadata, c + 1, "Peak_count", "%f", (float)(p->min_count + p->max_count)); + if (s->measure_perchannel & MEASURE_NOISE_FLOOR) + set_meta(metadata, c + 1, "Noise_floor"," %f", LINEAR_TO_DB(p->noise_floor)); if (s->measure_perchannel & MEASURE_BIT_DEPTH) { bit_depth(s, p->mask, p->imask, &depth); set_meta(metadata, c + 1, "Bit_depth", "%f", depth.num); @@ -458,6 +521,8 @@ static void set_metadata(AudioStatsContext *s, AVDictionary **metadata) set_meta(metadata, 0, "Overall.Flat_factor", "%f", LINEAR_TO_DB((min_runs + max_runs) / (min_count + max_count))); if (s->measure_overall & MEASURE_PEAK_COUNT) set_meta(metadata, 0, "Overall.Peak_count", "%f", (float)(min_count + max_count) / (double)s->nb_channels); + if (s->measure_overall & MEASURE_NOISE_FLOOR) + set_meta(metadata, 0, "Overall.Noise_floor", "%f", LINEAR_TO_DB(noise_floor)); if (s->measure_overall & MEASURE_BIT_DEPTH) { bit_depth(s, mask, imask, &depth); set_meta(metadata, 0, "Overall.Bit_depth", "%f", depth.num); @@ -572,6 +637,7 @@ static void print_stats(AVFilterContext *ctx) diff1_sum = 0, sigma_x = 0, sigma_x2 = 0, + noise_floor = 0, min_sigma_x2 = DBL_MAX, max_sigma_x2 =-DBL_MAX; AVRational depth; @@ -595,6 +661,7 @@ static void print_stats(AVFilterContext *ctx) max_sigma_x2 = FFMAX(max_sigma_x2, p->max_sigma_x2); sigma_x += p->sigma_x; sigma_x2 += p->sigma_x2; + noise_floor = FFMAX(noise_floor, p->noise_floor); min_count += p->min_count; max_count += p->max_count; min_runs += p->min_runs; @@ -638,6 +705,8 @@ static void print_stats(AVFilterContext *ctx) av_log(ctx, AV_LOG_INFO, "Flat factor: %f\n", LINEAR_TO_DB((p->min_runs + p->max_runs) / (p->min_count + p->max_count))); if (s->measure_perchannel & MEASURE_PEAK_COUNT) av_log(ctx, AV_LOG_INFO, "Peak count: %"PRId64"\n", p->min_count + p->max_count); + if (s->measure_perchannel & MEASURE_NOISE_FLOOR) + av_log(ctx, AV_LOG_INFO, "Noise floor dB: %f\n", LINEAR_TO_DB(p->noise_floor)); if (s->measure_perchannel & MEASURE_BIT_DEPTH) { bit_depth(s, p->mask, p->imask, &depth); av_log(ctx, AV_LOG_INFO, "Bit depth: %u/%u\n", depth.num, depth.den); @@ -684,6 +753,8 @@ static void print_stats(AVFilterContext *ctx) av_log(ctx, AV_LOG_INFO, "Flat factor: %f\n", LINEAR_TO_DB((min_runs + max_runs) / (min_count + max_count))); if (s->measure_overall & MEASURE_PEAK_COUNT) av_log(ctx, AV_LOG_INFO, "Peak count: %f\n", (min_count + max_count) / (double)s->nb_channels); + if (s->measure_overall & MEASURE_NOISE_FLOOR) + av_log(ctx, AV_LOG_INFO, "Noise floor dB: %f\n", LINEAR_TO_DB(noise_floor)); if (s->measure_overall & MEASURE_BIT_DEPTH) { bit_depth(s, mask, imask, &depth); av_log(ctx, AV_LOG_INFO, "Bit depth: %u/%u\n", depth.num, depth.den); @@ -704,6 +775,13 @@ static av_cold void uninit(AVFilterContext *ctx) if (s->nb_channels) print_stats(ctx); + if (s->chstats) { + for (int i = 0; i < s->nb_channels; i++) { + ChannelStats *p = &s->chstats[i]; + + av_freep(&p->win_samples); + } + } av_freep(&s->chstats); } |