/*
* Copyright (c) 2012 Clément Bœsch
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with FFmpeg; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
/**
* @file
* EBU R.128 implementation
* @see http://tech.ebu.ch/loudness
* @see https://www.youtube.com/watch?v=iuEtQqC-Sqo "EBU R128 Introduction - Florian Camerer"
* @todo implement start/stop/reset through filter command injection
* @todo support other frequencies to avoid resampling
*/
#include <math.h>
#include "libavutil/avassert.h"
#include "libavutil/avstring.h"
#include "libavutil/channel_layout.h"
#include "libavutil/dict.h"
#include "libavutil/xga_font_data.h"
#include "libavutil/opt.h"
#include "libavutil/timestamp.h"
#include "libswresample/swresample.h"
#include "audio.h"
#include "avfilter.h"
#include "formats.h"
#include "internal.h"
#define MAX_CHANNELS 63
/* pre-filter coefficients */
#define PRE_B0 1.53512485958697
#define PRE_B1 -2.69169618940638
#define PRE_B2 1.19839281085285
#define PRE_A1 -1.69065929318241
#define PRE_A2 0.73248077421585
/* RLB-filter coefficients */
#define RLB_B0 1.0
#define RLB_B1 -2.0
#define RLB_B2 1.0
#define RLB_A1 -1.99004745483398
#define RLB_A2 0.99007225036621
#define ABS_THRES -70 ///< silence gate: we discard anything below this absolute (LUFS) threshold
#define ABS_UP_THRES 10 ///< upper loud limit to consider (ABS_THRES being the minimum)
#define HIST_GRAIN 100 ///< defines histogram precision
#define HIST_SIZE ((ABS_UP_THRES - ABS_THRES) * HIST_GRAIN + 1)
/**
* A histogram is an array of HIST_SIZE hist_entry storing all the energies
* recorded (with an accuracy of 1/HIST_GRAIN) of the loudnesses from ABS_THRES
* (at 0) to ABS_UP_THRES (at HIST_SIZE-1).
* This fixed-size system avoids the need of a list of energies growing
* infinitely over the time and is thus more scalable.
*/
struct hist_entry {
int count; ///< how many times the corresponding value occurred
double energy; ///< E = 10^((L + 0.691) / 10)
double loudness; ///< L = -0.691 + 10 * log10(E)
};
struct integrator {
double *cache[MAX_CHANNELS]; ///< window of filtered samples (N ms)
int cache_pos; ///< focus on the last added bin in the cache array
double sum[MAX_CHANNELS]; ///< sum of the last N ms filtered samples (cache content)
int filled; ///< 1 if the cache is completely filled, 0 otherwise
double rel_threshold; ///< relative threshold
double sum_kept_powers; ///< sum of the powers (weighted sums) above absolute threshold
int nb_kept_powers; ///< number of sum above absolute threshold
struct hist_entry *histogram; ///< histogram of the powers, used to compute LRA and I
};
struct rect { int x, y, w, h; };
typedef struct {
const AVClass *class; ///< AVClass context for log and options purpose
/* peak metering */
int peak_mode; ///< enabled peak modes
double *true_peaks; ///< true peaks per channel
double *sample_peaks; ///< sample peaks per channel
double *true_peaks_per_frame; ///< true peaks in a frame per channel
#if CONFIG_SWRESAMPLE
SwrContext *swr_ctx; ///< over-sampling context for true peak metering
double *swr_buf; ///< resampled audio data for true peak metering
int swr_linesize;
#endif
/* video */
int do_video; ///< 1 if video output enabled, 0 otherwise
int w, h; ///< size of the video output
struct rect text; ///< rectangle for the LU legend on the left
struct rect graph; ///< rectangle for the main graph in the center
struct rect gauge; ///< rectangle for the gauge on the right
AVFrame *outpicref; ///< output picture reference, updated regularly
int meter; ///< select a EBU mode between +9 and +18
int scale_range; ///< the range of LU values according to the meter
int y_zero_lu; ///< the y value (pixel position) for 0 LU
int *y_line_ref; ///< y reference values for drawing the LU lines in the graph and the gauge
/* audio */
int nb_channels; ///< number of channels in the input
double *ch_weighting; ///< channel weighting mapping
int sample_count; ///< sample count used for refresh frequency, reset at refresh
/* Filter caches.
* The mult by 3 in the following is for X[i], X[i-1] and X[i-2] */
double x[MAX_CHANNELS * 3]; ///< 3 input samples cache for each channel
double y[MAX_CHANNELS * 3]; ///< 3 pre-filter samples cache for each channel
double z[MAX_CHANNELS * 3]; ///< 3 RLB-filter samples cache for each channel
#define I400_BINS (48000 * 4 / 10)
#define I3000_BINS (48000 * 3)
struct integrator i400; ///< 400ms integrator, used for Momentary loudness (M), and Integrated loudness (I)
struct integrator i3000; ///< 3s integrator, used for Short term loudness (S), and Loudness Range (LRA)
/* I and LRA specific */
double integrated_loudness; ///< integrated loudness in LUFS (I)
double loudness_range; ///< loudness range in LU (LRA)
double lra_low, lra_high; ///< low and high LRA values
/* misc */
int loglevel; ///< log level for frame logging
int metadata; ///< whether or not to inject loudness results in frames
} EBUR128Context;
enum {
PEAK_MODE_NONE = 0,
PEAK_MODE_SAMPLES_PEAKS = 1<<1,
PEAK_MODE_TRUE_PEAKS = 1<<2,
};
#define OFFSET(x) offsetof(EBUR128Context, x)
#define A AV_OPT_FLAG_AUDIO_PARAM
#define V AV_OPT_FLAG_VIDEO_PARAM
#define F AV_OPT_FLAG_FILTERING_PARAM
static const AVOption ebur128_options[] = {
{ "video", "set video output", OFFSET(do_video), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, V|F },
{ "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "640x480"}, 0, 0, V|F },
{ "meter", "set scale meter (+9 to +18)", OFFSET(meter), AV_OPT_TYPE_INT, {.i64 = 9}, 9, 18, V|F },
{ "framelog", "force frame logging level", OFFSET(loglevel), AV_OPT_TYPE_INT, {.i64 = -1}, INT_MIN, INT_MAX, A|V|F, "level" },
{ "info", "information logging level", 0, AV_OPT_TYPE_CONST, {.i64 = AV_LOG_INFO}, INT_MIN, INT_MAX, A|V|F, "level" },
{ "verbose", "verbose logging level", 0, AV_OPT_TYPE_CONST, {.i64 = AV_LOG_VERBOSE}, INT_MIN, INT_MAX, A|V|F, "level" },
{ "metadata", "inject metadata in the filtergraph", OFFSET(metadata), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, A|V|F },
{ "peak", "set peak mode", OFFSET(peak_mode), AV_OPT_TYPE_FLAGS, {.i64 = PEAK_MODE_NONE}, 0, INT_MAX, A|F, "mode" },
{ "none", "disable any peak mode", 0, AV_OPT_TYPE_CONST, {.i64 = PEAK_MODE_NONE}, INT_MIN, INT_MAX, A|F, "mode" },
{ "sample", "enable peak-sample mode", 0, AV_OPT_TYPE_CONST, {.i64 = PEAK_MODE_SAMPLES_PEAKS}, INT_MIN, INT_MAX, A|F, "mode" },
{ "true", "enable true-peak mode", 0, AV_OPT_TYPE_CONST, {.i64 = PEAK_MODE_TRUE_PEAKS}, INT_MIN, INT_MAX, A|F, "mode" },
{ NULL },
};
AVFILTER_DEFINE_CLASS(ebur128);
static const uint8_t graph_colors[] = {
0xdd, 0x66, 0x66, // value above 0LU non reached
0x66, 0x66, 0xdd, // value below 0LU non reached
0x96, 0x33, 0x33, // value above 0LU reached
0x33, 0x33, 0x96, // value below 0LU reached
0xdd, 0x96, 0x96, // value above 0LU line non reached
0x96, 0x96, 0xdd, // value below 0LU line non reached
0xdd, 0x33, 0x33, // value above 0LU line reached
0x33, 0x33, 0xdd, // value below 0LU line reached
};
static const uint8_t *get_graph_color(const EBUR128Context *ebur128, int v, int y)
{
const int below0 = y > ebur128->y_zero_lu;
const int reached = y >= v;
const int line = ebur128->y_line_ref[y] || y == ebur128->y_zero_lu;
const int colorid = 4*line + 2*reached + below0;
return graph_colors + 3*colorid;
}
static inline int lu_to_y(const EBUR128Context *ebur128, double v)
{
v += 2 * ebur128->meter; // make it in range [0;...]
v = av_clipf(v, 0, ebur128->scale_range); // make sure it's in the graph scale
v = ebur128->scale_range - v; // invert value (y=0 is on top)
return v * ebur128->graph.h / ebur128->scale_range; // rescale from scale range to px height
}
#define FONT8 0
#define FONT16 1
static const uint8_t font_colors[] = {
0xdd, 0xdd, 0x00,
0x00, 0x96, 0x96,
};
static void drawtext(AVFrame *pic, int x, int y, int ftid, const uint8_t *color, const char *fmt, ...)
{
int i;
char buf[128] = {0};
const uint8_t *font;
int font_height;
va_list vl;
if (ftid == FONT16) font = avpriv_vga16_font, font_height = 16;
else if (ftid == FONT8) font = avpriv_cga_font, font_height = 8;
else return;
vsnprintf(buf, sizeof(buf), fmt, vl);
for (i = 0; buf[i]; i++) {
int char_y, mask;
uint8_t *p = pic->data[0] + y*pic->linesize[0] + (x + i*8)*3;
for (char_y = 0; char_y < font_height; char_y++) {
for (mask = 0x80; mask; mask >>= 1) {
if (font[buf[i] * font_height + char_y] & mask)
else
p += 3;
}
p += pic->linesize[0] - 8*3;
}
}
}
static void drawline(AVFrame *pic, int x, int y, int len, int step)
{
int i;
uint8_t *p = pic->data[0] + y*pic->linesize[0] + x*3;
for (i = 0; i < len; i++) {
p += step;
}
}
static int config_video_output(AVFilterLink *outlink)
{
int i, x, y;
uint8_t *p;
AVFilterContext *ctx = outlink->src;
EBUR128Context *ebur128 = ctx->priv;
AVFrame *outpicref;
/* check if there is enough space to represent everything decently */
if (ebur128->w < 640 || ebur128->h < 480) {
av_log(ctx, AV_LOG_ERROR, "Video size %dx%d is too small, "
"minimum size is 640x480\n", ebur128->w, ebur128->h);
return AVERROR(EINVAL);
}
outlink->w = ebur128->w;
outlink->h = ebur128->h;
#define PAD 8
/* configure text area position and size */
ebur128->text.x = PAD;
ebur128->text.y = 40;
ebur128->text.w = 3 * 8; // 3 characters
ebur128->text.h = ebur128->h - PAD - ebur128->text.y;
/* configure gauge position and size */
ebur128->gauge.w = 20;
ebur128->gauge.h = ebur128->text.h;
ebur128->gauge.x = ebur128->w - PAD - ebur128->gauge.w;
ebur128->gauge.y = ebur128->text.y;
/* configure graph position and size */
ebur128->graph.x = ebur128->text.x + ebur128->text.w + PAD;
ebur128->graph.y = ebur128->gauge.y;
ebur128->graph.w = ebur128->gauge.x - ebur128->graph.x - PAD;
ebur128->graph.h = ebur128->gauge.h;
/* graph and gauge share the LU-to-pixel code */
av_assert0(ebur128->graph.h == ebur128->gauge.h);
/* prepare the initial picref buffer */
av_frame_free(&ebur128->outpicref);
ebur128->outpicref = outpicref =
ff_get_video_buffer(outlink, outlink->w, outlink->h);
if (!outpicref)
return AVERROR(ENOMEM);
outlink->sample_aspect_ratio = (AVRational){1,1};
/* init y references values (to draw LU lines) */
ebur128->y_line_ref = av_calloc(ebur128->graph.h + 1, sizeof(*ebur128->y_line_ref));
if (!ebur128->y_line_ref)
return AVERROR(ENOMEM);
/* black background */
memset(outpicref
->data
[0], 0, ebur128
->h
* outpicref
->linesize
[0]);
/* draw LU legends */
drawtext(outpicref, PAD, PAD+16, FONT8, font_colors+3, " LU");
for (i = ebur128->meter; i >= -ebur128->meter * 2; i--) {
y = lu_to_y(ebur128, i);
x = PAD + (i < 10 && i > -10) * 8;
ebur128->y_line_ref[y] = i;
y -= 4; // -4 to center vertically
drawtext(outpicref, x, y + ebur128->graph.y, FONT8, font_colors+3,
"%c%d", i < 0 ? '-' : i > 0 ? '+' : ' ', FFABS(i));
}
/* draw graph */
ebur128->y_zero_lu = lu_to_y(ebur128, 0);
p = outpicref->data[0] + ebur128->graph.y * outpicref->linesize[0]
+ ebur128->graph.x * 3;
for (y = 0; y < ebur128->graph.h; y++) {
const uint8_t *c = get_graph_color(ebur128, INT_MAX, y);
for (x = 0; x < ebur128->graph.w; x++)
p += outpicref->linesize[0];
}
/* draw fancy rectangles around the graph and the gauge */
#define DRAW_RECT(r) do { \
drawline(outpicref, r.x, r.y - 1, r.w, 3); \
drawline(outpicref, r.x, r.y + r.h, r.w, 3); \
drawline(outpicref, r.x - 1, r.y, r.h, outpicref->linesize[0]); \
drawline(outpicref, r.x + r.w, r.y, r.h, outpicref->linesize[0]); \
} while (0)
DRAW_RECT(ebur128->graph);
DRAW_RECT(ebur128->gauge);
outlink->flags |= FF_LINK_FLAG_REQUEST_LOOP;
return 0;
}
static int config_audio_input(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
EBUR128Context *ebur128 = ctx->priv;
/* Force 100ms framing in case of metadata injection: the frames must have
* a granularity of the window overlap to be accurately exploited.
* As for the true peaks mode, it just simplifies the resampling buffer
* allocation and the lookup in it (since sample buffers differ in size, it
* can be more complex to integrate in the one-sample loop of
* filter_frame()). */
if (ebur128->metadata || (ebur128->peak_mode & PEAK_MODE_TRUE_PEAKS))
inlink->min_samples =
inlink->max_samples =
inlink->partial_buf_size = inlink->sample_rate / 10;
return 0;
}
static int config_audio_output(AVFilterLink *outlink)
{
int i;
AVFilterContext *ctx = outlink->src;
EBUR128Context *ebur128 = ctx->priv;
const int nb_channels = av_get_channel_layout_nb_channels(outlink->channel_layout);
#define BACK_MASK (AV_CH_BACK_LEFT |AV_CH_BACK_CENTER |AV_CH_BACK_RIGHT| \
AV_CH_TOP_BACK_LEFT|AV_CH_TOP_BACK_CENTER|AV_CH_TOP_BACK_RIGHT| \
AV_CH_SIDE_LEFT |AV_CH_SIDE_RIGHT| \
AV_CH_SURROUND_DIRECT_LEFT |AV_CH_SURROUND_DIRECT_RIGHT)
ebur128->nb_channels = nb_channels;
ebur128->ch_weighting = av_calloc(nb_channels, sizeof(*ebur128->ch_weighting));
if (!ebur128->ch_weighting)
return AVERROR(ENOMEM);
for (i = 0; i < nb_channels; i++) {
/* channel weighting */
const uint16_t chl = av_channel_layout_extract_channel(outlink->channel_layout, i);
if (chl & (AV_CH_LOW_FREQUENCY|AV_CH_LOW_FREQUENCY_2)) {
ebur128->ch_weighting[i] = 0;
} else if (chl & BACK_MASK) {
ebur128->ch_weighting[i] = 1.41;
} else {
ebur128->ch_weighting[i] = 1.0;
}
if (!ebur128->ch_weighting[i])
continue;
/* bins buffer for the two integration window (400ms and 3s) */
ebur128->i400.cache[i] = av_calloc(I400_BINS, sizeof(*ebur128->i400.cache[0]));
ebur128->i3000.cache[i] = av_calloc(I3000_BINS, sizeof(*ebur128->i3000.cache[0]));
if (!ebur128->i400.cache[i] || !ebur128->i3000.cache[i])
return AVERROR(ENOMEM);
}
outlink->flags |= FF_LINK_FLAG_REQUEST_LOOP;
#if CONFIG_SWRESAMPLE
if (ebur128->peak_mode & PEAK_MODE_TRUE_PEAKS) {
int ret;
ebur128->swr_buf = av_malloc_array(nb_channels, 19200 * sizeof(double));
ebur128->true_peaks = av_calloc(nb_channels, sizeof(*ebur128->true_peaks));
ebur128->true_peaks_per_frame = av_calloc(nb_channels, sizeof(*ebur128->true_peaks_per_frame));
ebur128->swr_ctx = swr_alloc();
if (!ebur128->swr_buf || !ebur128->true_peaks ||
!ebur128->true_peaks_per_frame || !ebur128->swr_ctx)
return AVERROR(ENOMEM);
av_opt_set_int(ebur128->swr_ctx, "in_channel_layout", outlink->channel_layout, 0);
av_opt_set_int(ebur128->swr_ctx, "in_sample_rate", outlink->sample_rate, 0);
av_opt_set_sample_fmt(ebur128->swr_ctx, "in_sample_fmt", outlink->format, 0);
av_opt_set_int(ebur128->swr_ctx, "out_channel_layout", outlink->channel_layout, 0);
av_opt_set_int(ebur128->swr_ctx, "out_sample_rate", 192000, 0);
av_opt_set_sample_fmt(ebur128->swr_ctx, "out_sample_fmt", outlink->format, 0);
ret = swr_init(ebur128->swr_ctx);
if (ret < 0)
return ret;
}
#endif
if (ebur128->peak_mode & PEAK_MODE_SAMPLES_PEAKS) {
ebur128->sample_peaks = av_calloc(nb_channels, sizeof(*ebur128->sample_peaks));
if (!ebur128->sample_peaks)
return AVERROR(ENOMEM);
}
return 0;
}
#define ENERGY(loudness) (pow(10, ((loudness) + 0.691) / 10.))
#define LOUDNESS(energy) (-0.691 + 10 * log10(energy))
#define DBFS(energy) (20 * log10(energy))
static struct hist_entry *get_histogram(void)
{
int i;
struct hist_entry *h = av_calloc(HIST_SIZE, sizeof(*h));
if (!h)
return NULL;
for (i = 0; i < HIST_SIZE; i++) {
h[i].loudness = i / (double)HIST_GRAIN + ABS_THRES;
h[i].energy = ENERGY(h[i].loudness);
}
return h;
}
static av_cold int init(AVFilterContext *ctx)
{
EBUR128Context *ebur128 = ctx->priv;
AVFilterPad pad;
if (ebur128->loglevel != AV_LOG_INFO &&
ebur128->loglevel != AV_LOG_VERBOSE) {
if (ebur128->do_video || ebur128->metadata)
ebur128->loglevel = AV_LOG_VERBOSE;
else
ebur128->loglevel = AV_LOG_INFO;
}
if (!CONFIG_SWRESAMPLE && (ebur128->peak_mode & PEAK_MODE_TRUE_PEAKS)) {
av_log(ctx, AV_LOG_ERROR,
"True-peak mode requires libswresample to be performed\n");
return AVERROR(EINVAL);
}
// if meter is +9 scale, scale range is from -18 LU to +9 LU (or 3*9)
// if meter is +18 scale, scale range is from -36 LU to +18 LU (or 3*18)
ebur128->scale_range = 3 * ebur128->meter;
ebur128->i400.histogram = get_histogram();
ebur128->i3000.histogram = get_histogram();
if (!ebur128->i400.histogram || !ebur128->i3000.histogram)
return AVERROR(ENOMEM);
ebur128->integrated_loudness = ABS_THRES;
ebur128->loudness_range = 0;
/* insert output pads */
if (ebur128->do_video) {
pad = (AVFilterPad){
.name = av_strdup("out0"),
.type = AVMEDIA_TYPE_VIDEO,
.config_props = config_video_output,
};
if (!pad.name)
return AVERROR(ENOMEM);
ff_insert_outpad(ctx, 0, &pad);
}
pad = (AVFilterPad){
.name = av_asprintf("out%d", ebur128->do_video),
.type = AVMEDIA_TYPE_AUDIO,
.config_props = config_audio_output,
};
if (!pad.name)
return AVERROR(ENOMEM);
ff_insert_outpad(ctx, ebur128->do_video, &pad);
/* summary */
av_log(ctx, AV_LOG_VERBOSE, "EBU +%d scale\n", ebur128->meter);
return 0;
}
#define HIST_POS(power) (int)(((power) - ABS_THRES) * HIST_GRAIN)
/* loudness and power should be set such as loudness = -0.691 +
* 10*log10(power), we just avoid doing that calculus two times */
static int gate_update(struct integrator *integ, double power,
double loudness, int gate_thres)
{
int ipower;
double relative_threshold;
int gate_hist_pos;
/* update powers histograms by incrementing current power count */
ipower = av_clip(HIST_POS(loudness), 0, HIST_SIZE - 1);
integ->histogram[ipower].count++;
/* compute relative threshold and get its position in the histogram */
integ->sum_kept_powers += power;
integ->nb_kept_powers++;
relative_threshold = integ->sum_kept_powers / integ->nb_kept_powers;
if (!relative_threshold)
relative_threshold = 1e-12;
integ->rel_threshold = LOUDNESS(relative_threshold) + gate_thres;
gate_hist_pos = av_clip(HIST_POS(integ->rel_threshold), 0, HIST_SIZE - 1);
return gate_hist_pos;
}
static int filter_frame(AVFilterLink *inlink, AVFrame *insamples)
{
int i, ch, idx_insample;
AVFilterContext *ctx = inlink->dst;
EBUR128Context *ebur128 = ctx->priv;
const int nb_channels = ebur128->nb_channels;
const int nb_samples = insamples->nb_samples;
const double *samples = (double *)insamples->data[0];
AVFrame *pic = ebur128->outpicref;
#if CONFIG_SWRESAMPLE
if (ebur128->peak_mode & PEAK_MODE_TRUE_PEAKS) {
const double *swr_samples = ebur128->swr_buf;
int ret = swr_convert(ebur128->swr_ctx, (uint8_t**)&ebur128->swr_buf, 19200,
(const uint8_t **)insamples->data, nb_samples);
if (ret < 0)
return ret;
for (ch = 0; ch < nb_channels; ch++)
ebur128->true_peaks_per_frame[ch] = 0.0;
for (idx_insample = 0; idx_insample < ret; idx_insample++) {
for (ch = 0; ch < nb_channels; ch++) {
ebur128->true_peaks[ch] = FFMAX(ebur128->true_peaks[ch], FFABS(*swr_samples));
ebur128->true_peaks_per_frame[ch] = FFMAX(ebur128->true_peaks_per_frame[ch],
FFABS(*swr_samples));
swr_samples++;
}
}
}
#endif
for (idx_insample = 0; idx_insample < nb_samples; idx_insample++) {
const int bin_id_400 = ebur128->i400.cache_pos;
const int bin_id_3000 = ebur128->i3000.cache_pos;
#define MOVE_TO_NEXT_CACHED_ENTRY(time) do { \
ebur128->i##time.cache_pos++; \
if (ebur128->i##time.cache_pos == I##time##_BINS) { \
ebur128->i##time.filled = 1; \
ebur128->i##time.cache_pos = 0; \
} \
} while (0)
MOVE_TO_NEXT_CACHED_ENTRY(400);
MOVE_TO_NEXT_CACHED_ENTRY(3000);
for (ch = 0; ch < nb_channels; ch++) {
double bin;
if (ebur128->peak_mode & PEAK_MODE_SAMPLES_PEAKS)
ebur128->sample_peaks[ch] = FFMAX(ebur128->sample_peaks[ch], FFABS(*samples));
ebur128->x[ch * 3] = *samples++; // set X[i]
if (!ebur128->ch_weighting[ch])
continue;
/* Y[i] = X[i]*b0 + X[i-1]*b1 + X[i-2]*b2 - Y[i-1]*a1 - Y[i-2]*a2 */
#define FILTER(Y, X, name) do { \
double *dst = ebur128->Y + ch*3; \
double *src = ebur128->X + ch*3; \
dst[2] = dst[1]; \
dst[1] = dst[0]; \
dst[0] = src[0]*name##_B0 + src[1]*name##_B1 + src[2]*name##_B2 \
- dst[1]*name##_A1 - dst[2]*name##_A2; \
} while (0)
// TODO: merge both filters in one?
FILTER(y, x, PRE); // apply pre-filter
ebur128->x[ch * 3 + 2] = ebur128->x[ch * 3 + 1];
ebur128->x[ch * 3 + 1] = ebur128->x[ch * 3 ];
FILTER(z, y, RLB); // apply RLB-filter
bin = ebur128->z[ch * 3] * ebur128->z[ch * 3];
/* add the new value, and limit the sum to the cache size (400ms or 3s)
* by removing the oldest one */
ebur128->i400.sum [ch] = ebur128->i400.sum [ch] + bin - ebur128->i400.cache [ch][bin_id_400];
ebur128->i3000.sum[ch] = ebur128->i3000.sum[ch] + bin - ebur128->i3000.cache[ch][bin_id_3000];
/* override old cache entry with the new value */
ebur128->i400.cache [ch][bin_id_400 ] = bin;
ebur128->i3000.cache[ch][bin_id_3000] = bin;
}
/* For integrated loudness, gating blocks are 400ms long with 75%
* overlap (see BS.1770-2 p5), so a re-computation is needed each 100ms
* (4800 samples at 48kHz). */
if (++ebur128->sample_count == 4800) {
double loudness_400, loudness_3000;
double power_400 = 1e-12, power_3000 = 1e-12;
AVFilterLink *outlink = ctx->outputs[0];
const int64_t pts = insamples->pts +
av_rescale_q(idx_insample, (AVRational){ 1, inlink->sample_rate },
outlink->time_base);
ebur128->sample_count = 0;
#define COMPUTE_LOUDNESS(m, time) do { \
if (ebur128->i##time.filled) { \
/* weighting sum of the last <time> ms */ \
for (ch = 0; ch < nb_channels; ch++) \
power_##time += ebur128->ch_weighting[ch] * ebur128->i##time.sum[ch]; \
power_##time /= I##time##_BINS; \
} \
loudness_##time = LOUDNESS(power_##time); \
} while (0)
COMPUTE_LOUDNESS(M, 400);
COMPUTE_LOUDNESS(S, 3000);
/* Integrated loudness */
#define I_GATE_THRES -10 // initially defined to -8 LU in the first EBU standard
if (loudness_400 >= ABS_THRES) {
double integrated_sum = 0;
int nb_integrated = 0;
int gate_hist_pos = gate_update(&ebur128->i400, power_400,
loudness_400, I_GATE_THRES);
/* compute integrated loudness by summing the histogram values
* above the relative threshold */
for (i = gate_hist_pos; i < HIST_SIZE; i++) {
const int nb_v = ebur128->i400.histogram[i].count;
nb_integrated += nb_v;
integrated_sum += nb_v * ebur128->i400.histogram[i].energy;
}
if (nb_integrated)
ebur128->integrated_loudness = LOUDNESS(integrated_sum / nb_integrated);
}
/* LRA */
#define LRA_GATE_THRES -20
#define LRA_LOWER_PRC 10
#define LRA_HIGHER_PRC 95
/* XXX: example code in EBU 3342 is ">=" but formula in BS.1770
* specs is ">" */
if (loudness_3000 >= ABS_THRES) {
int nb_powers = 0;
int gate_hist_pos = gate_update(&ebur128->i3000, power_3000,
loudness_3000, LRA_GATE_THRES);
for (i = gate_hist_pos; i < HIST_SIZE; i++)
nb_powers += ebur128->i3000.histogram[i].count;
if (nb_powers) {
int n, nb_pow;
/* get lower loudness to consider */
n = 0;
nb_pow = LRA_LOWER_PRC * nb_powers / 100. + 0.5;
for (i = gate_hist_pos; i < HIST_SIZE; i++) {
n += ebur128->i3000.histogram[i].count;
if (n >= nb_pow) {
ebur128->lra_low = ebur128->i3000.histogram[i].loudness;
break;
}
}
/* get higher loudness to consider */
n = nb_powers;
nb_pow = LRA_HIGHER_PRC * nb_powers / 100. + 0.5;
for (i = HIST_SIZE - 1; i >= 0; i--) {
n -= ebur128->i3000.histogram[i].count;
if (n < nb_pow) {
ebur128->lra_high = ebur128->i3000.histogram[i].loudness;
break;
}
}
// XXX: show low & high on the graph?
ebur128->loudness_range = ebur128->lra_high - ebur128->lra_low;
}
}
#define LOG_FMT "M:%6.1f S:%6.1f I:%6.1f LUFS LRA:%6.1f LU"
/* push one video frame */
if (ebur128->do_video) {
int x, y, ret;
uint8_t *p;
const int y_loudness_lu_graph = lu_to_y(ebur128, loudness_3000 + 23);
const int y_loudness_lu_gauge = lu_to_y(ebur128, loudness_400 + 23);
/* draw the graph using the short-term loudness */
p = pic->data[0] + ebur128->graph.y*pic->linesize[0] + ebur128->graph.x*3;
for (y = 0; y < ebur128->graph.h; y++) {
const uint8_t *c = get_graph_color(ebur128, y_loudness_lu_graph, y);
memmove(p
, p
+ 3, (ebur128
->graph.
w - 1) * 3); memcpy(p
+ (ebur128
->graph.
w - 1) * 3, c
, 3); p += pic->linesize[0];
}
/* draw the gauge using the momentary loudness */
p = pic->data[0] + ebur128->gauge.y*pic->linesize[0] + ebur128->gauge.x*3;
for (y = 0; y < ebur128->gauge.h; y++) {
const uint8_t *c = get_graph_color(ebur128, y_loudness_lu_gauge, y);
for (x = 0; x < ebur128->gauge.w; x++)
p += pic->linesize[0];
}
/* draw textual info */
drawtext(pic, PAD, PAD - PAD/2, FONT16, font_colors,
LOG_FMT " ", // padding to erase trailing characters
loudness_400, loudness_3000,
ebur128->integrated_loudness, ebur128->loudness_range);
/* set pts and push frame */
pic->pts = pts;
ret = ff_filter_frame(outlink, av_frame_clone(pic));
if (ret < 0)
return ret;
}
if (ebur128->metadata) { /* happens only once per filter_frame call */
char metabuf[128];
#define META_PREFIX "lavfi.r128."
#define SET_META(name, var) do { \
snprintf(metabuf, sizeof(metabuf), "%.3f", var); \
av_dict_set(&insamples->metadata, name, metabuf, 0); \
} while (0)
#define SET_META_PEAK(name, ptype) do { \
if (ebur128->peak_mode & PEAK_MODE_ ## ptype ## _PEAKS) { \
char key[64]; \
for (ch = 0; ch < nb_channels; ch++) { \
snprintf(key, sizeof(key), \
META_PREFIX AV_STRINGIFY(name) "_peaks_ch%d", ch); \
SET_META(key, ebur128->name##_peaks[ch]); \
} \
} \
} while (0)
SET_META(META_PREFIX "M", loudness_400);
SET_META(META_PREFIX "S", loudness_3000);
SET_META(META_PREFIX "I", ebur128->integrated_loudness);
SET_META(META_PREFIX "LRA", ebur128->loudness_range);
SET_META(META_PREFIX "LRA.low", ebur128->lra_low);
SET_META(META_PREFIX "LRA.high", ebur128->lra_high);
SET_META_PEAK(sample, SAMPLES);
SET_META_PEAK(true, TRUE);
}
av_log(ctx, ebur128->loglevel, "t: %-10s " LOG_FMT,
av_ts2timestr(pts, &outlink->time_base),
loudness_400, loudness_3000,
ebur128->integrated_loudness, ebur128->loudness_range);
#define PRINT_PEAKS(str, sp, ptype) do { \
if (ebur128->peak_mode & PEAK_MODE_ ## ptype ## _PEAKS) { \
av_log(ctx, ebur128->loglevel, " " str ":"); \
for (ch = 0; ch < nb_channels; ch++) \
av_log(ctx, ebur128->loglevel, " %5.1f", DBFS(sp[ch])); \
av_log(ctx, ebur128->loglevel, " dBFS"); \
} \
} while (0)
PRINT_PEAKS("SPK", ebur128->sample_peaks, SAMPLES);
PRINT_PEAKS("FTPK", ebur128->true_peaks_per_frame, TRUE);
PRINT_PEAKS("TPK", ebur128->true_peaks, TRUE);
av_log(ctx, ebur128->loglevel, "\n");
}
}
return ff_filter_frame(ctx->outputs[ebur128->do_video], insamples);
}
static int query_formats(AVFilterContext *ctx)
{
EBUR128Context *ebur128 = ctx->priv;
AVFilterFormats *formats;
AVFilterChannelLayouts *layouts;
AVFilterLink *inlink = ctx->inputs[0];
AVFilterLink *outlink = ctx->outputs[0];
static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_NONE };
static const int input_srate[] = {48000, -1}; // ITU-R BS.1770 provides coeff only for 48kHz
static const enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_RGB24, AV_PIX_FMT_NONE };
/* set optional output video format */
if (ebur128->do_video) {
formats = ff_make_format_list(pix_fmts);
if (!formats)
return AVERROR(ENOMEM);
ff_formats_ref(formats, &outlink->in_formats);
outlink = ctx->outputs[1];
}
/* set input and output audio formats
* Note: ff_set_common_* functions are not used because they affect all the
* links, and thus break the video format negotiation */
formats = ff_make_format_list(sample_fmts);
if (!formats)
return AVERROR(ENOMEM);
ff_formats_ref(formats, &inlink->out_formats);
ff_formats_ref(formats, &outlink->in_formats);
layouts = ff_all_channel_layouts();
if (!layouts)
return AVERROR(ENOMEM);
ff_channel_layouts_ref(layouts, &inlink->out_channel_layouts);
ff_channel_layouts_ref(layouts, &outlink->in_channel_layouts);
formats = ff_make_format_list(input_srate);
if (!formats)
return AVERROR(ENOMEM);
ff_formats_ref(formats, &inlink->out_samplerates);
ff_formats_ref(formats, &outlink->in_samplerates);
return 0;
}
static av_cold void uninit(AVFilterContext *ctx)
{
int i;
EBUR128Context *ebur128 = ctx->priv;
av_log(ctx, AV_LOG_INFO, "Summary:\n\n"
" Integrated loudness:\n"
" I: %5.1f LUFS\n"
" Threshold: %5.1f LUFS\n\n"
" Loudness range:\n"
" LRA: %5.1f LU\n"
" Threshold: %5.1f LUFS\n"
" LRA low: %5.1f LUFS\n"
" LRA high: %5.1f LUFS",
ebur128->integrated_loudness, ebur128->i400.rel_threshold,
ebur128->loudness_range, ebur128->i3000.rel_threshold,
ebur128->lra_low, ebur128->lra_high);
#define PRINT_PEAK_SUMMARY(str, sp, ptype) do { \
int ch; \
double maxpeak; \
maxpeak = 0.0; \
if (ebur128->peak_mode & PEAK_MODE_ ## ptype ## _PEAKS) { \
for (ch = 0; ch < ebur128->nb_channels; ch++) \
maxpeak = FFMAX(maxpeak, sp[ch]); \
av_log(ctx, AV_LOG_INFO, "\n\n " str " peak:\n" \
" Peak: %5.1f dBFS", \
DBFS(maxpeak)); \
} \
} while (0)
PRINT_PEAK_SUMMARY("Sample", ebur128->sample_peaks, SAMPLES);
PRINT_PEAK_SUMMARY("True", ebur128->true_peaks, TRUE);
av_log(ctx, AV_LOG_INFO, "\n");
av_freep(&ebur128->y_line_ref);
av_freep(&ebur128->ch_weighting);
av_freep(&ebur128->true_peaks);
av_freep(&ebur128->sample_peaks);
av_freep(&ebur128->true_peaks_per_frame);
av_freep(&ebur128->i400.histogram);
av_freep(&ebur128->i3000.histogram);
for (i = 0; i < ebur128->nb_channels; i++) {
av_freep(&ebur128->i400.cache[i]);
av_freep(&ebur128->i3000.cache[i]);
}
for (i = 0; i < ctx->nb_outputs; i++)
av_freep(&ctx->output_pads[i].name);
av_frame_free(&ebur128->outpicref);
#if CONFIG_SWRESAMPLE
av_freep(&ebur128->swr_buf);
swr_free(&ebur128->swr_ctx);
#endif
}
static const AVFilterPad ebur128_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
.filter_frame = filter_frame,
.config_props = config_audio_input,
},
{ NULL }
};
AVFilter ff_af_ebur128 = {
.name = "ebur128",
.description = NULL_IF_CONFIG_SMALL("EBU R128 scanner."),
.priv_size = sizeof(EBUR128Context),
.init = init,
.uninit = uninit,
.query_formats = query_formats,
.inputs = ebur128_inputs,
.outputs = NULL,
.priv_class = &ebur128_class,
.flags = AVFILTER_FLAG_DYNAMIC_OUTPUTS,
};