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/* flac - Command-line FLAC encoder/decoder
* Copyright (C) 2000,2001,2002,2003,2004,2005 Josh Coalson
*
* This program 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.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "FLAC/all.h"
#include "analyze.h"
typedef struct {
FLAC__int32 residual;
unsigned count;
} pair_t;
typedef struct {
pair_t buckets[FLAC__MAX_BLOCK_SIZE];
int peak_index;
unsigned nbuckets;
unsigned nsamples;
double sum, sos;
double variance;
double mean;
double stddev;
} subframe_stats_t;
static subframe_stats_t all_;
static void init_stats(subframe_stats_t *stats);
static void update_stats(subframe_stats_t *stats, FLAC__int32 residual, unsigned incr);
static void compute_stats(subframe_stats_t *stats);
static FLAC__bool dump_stats(const subframe_stats_t *stats, const char *filename);
void flac__analyze_init(analysis_options aopts)
{
if(aopts.do_residual_gnuplot) {
init_stats(&all_);
}
}
void flac__analyze_frame(const FLAC__Frame *frame, unsigned frame_number, analysis_options aopts, FILE *fout)
{
const unsigned channels = frame->header.channels;
char outfilename[1024];
subframe_stats_t stats;
unsigned i, channel;
/* do the human-readable part first */
fprintf(fout, "frame=%u\tblocksize=%u\tsample_rate=%u\tchannels=%u\tchannel_assignment=%s\n", frame_number, frame->header.blocksize, frame->header.sample_rate, channels, FLAC__ChannelAssignmentString[frame->header.channel_assignment]);
for(channel = 0; channel < channels; channel++) {
const FLAC__Subframe *subframe = frame->subframes+channel;
fprintf(fout, "\tsubframe=%u\twasted_bits=%u\ttype=%s", channel, subframe->wasted_bits, FLAC__SubframeTypeString[subframe->type]);
switch(subframe->type) {
case FLAC__SUBFRAME_TYPE_CONSTANT:
fprintf(fout, "\tvalue=%d\n", subframe->data.constant.value);
break;
case FLAC__SUBFRAME_TYPE_FIXED:
FLAC__ASSERT(subframe->data.fixed.entropy_coding_method.type == FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE);
fprintf(fout, "\torder=%u\tpartition_order=%u\n", subframe->data.fixed.order, subframe->data.fixed.entropy_coding_method.data.partitioned_rice.order);
for(i = 0; i < subframe->data.fixed.order; i++)
fprintf(fout, "\t\twarmup[%u]=%d\n", i, subframe->data.fixed.warmup[i]);
if(aopts.do_residual_text) {
const unsigned partitions = (1u << subframe->data.fixed.entropy_coding_method.data.partitioned_rice.order);
for(i = 0; i < partitions; i++) {
unsigned parameter = subframe->data.fixed.entropy_coding_method.data.partitioned_rice.contents->parameters[i];
if(parameter == FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ESCAPE_PARAMETER)
fprintf(fout, "\t\tparameter[%u]=ESCAPE, raw_bits=%u\n", i, subframe->data.fixed.entropy_coding_method.data.partitioned_rice.contents->raw_bits[i]);
else
fprintf(fout, "\t\tparameter[%u]=%u\n", i, parameter);
}
for(i = 0; i < frame->header.blocksize-subframe->data.fixed.order; i++)
fprintf(fout, "\t\tresidual[%u]=%d\n", i, subframe->data.fixed.residual[i]);
}
break;
case FLAC__SUBFRAME_TYPE_LPC:
FLAC__ASSERT(subframe->data.lpc.entropy_coding_method.type == FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE);
fprintf(fout, "\torder=%u\tpartition_order=%u\tqlp_coeff_precision=%u\tquantization_level=%d\n", subframe->data.lpc.order, subframe->data.lpc.entropy_coding_method.data.partitioned_rice.order, subframe->data.lpc.qlp_coeff_precision, subframe->data.lpc.quantization_level);
for(i = 0; i < subframe->data.lpc.order; i++)
fprintf(fout, "\t\twarmup[%u]=%d\n", i, subframe->data.lpc.warmup[i]);
if(aopts.do_residual_text) {
const unsigned partitions = (1u << subframe->data.lpc.entropy_coding_method.data.partitioned_rice.order);
for(i = 0; i < partitions; i++) {
unsigned parameter = subframe->data.lpc.entropy_coding_method.data.partitioned_rice.contents->parameters[i];
if(parameter == FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ESCAPE_PARAMETER)
fprintf(fout, "\t\tparameter[%u]=ESCAPE, raw_bits=%u\n", i, subframe->data.lpc.entropy_coding_method.data.partitioned_rice.contents->raw_bits[i]);
else
fprintf(fout, "\t\tparameter[%u]=%u\n", i, parameter);
}
for(i = 0; i < frame->header.blocksize-subframe->data.lpc.order; i++)
fprintf(fout, "\t\tresidual[%u]=%d\n", i, subframe->data.lpc.residual[i]);
}
break;
case FLAC__SUBFRAME_TYPE_VERBATIM:
fprintf(fout, "\n");
break;
}
}
/* now do the residual distributions if requested */
if(aopts.do_residual_gnuplot) {
for(channel = 0; channel < channels; channel++) {
const FLAC__Subframe *subframe = frame->subframes+channel;
unsigned residual_samples;
init_stats(&stats);
switch(subframe->type) {
case FLAC__SUBFRAME_TYPE_FIXED:
residual_samples = frame->header.blocksize - subframe->data.fixed.order;
for(i = 0; i < residual_samples; i++)
update_stats(&stats, subframe->data.fixed.residual[i], 1);
break;
case FLAC__SUBFRAME_TYPE_LPC:
residual_samples = frame->header.blocksize - subframe->data.lpc.order;
for(i = 0; i < residual_samples; i++)
update_stats(&stats, subframe->data.lpc.residual[i], 1);
break;
default:
break;
}
/* update all_ */
for(i = 0; i < stats.nbuckets; i++) {
update_stats(&all_, stats.buckets[i].residual, stats.buckets[i].count);
}
/* write the subframe */
sprintf(outfilename, "f%06u.s%u.gp", frame_number, channel);
compute_stats(&stats);
(void)dump_stats(&stats, outfilename);
}
}
}
void flac__analyze_finish(analysis_options aopts)
{
if(aopts.do_residual_gnuplot) {
compute_stats(&all_);
(void)dump_stats(&all_, "all");
}
}
void init_stats(subframe_stats_t *stats)
{
stats->peak_index = -1;
stats->nbuckets = 0;
stats->nsamples = 0;
stats->sum = 0.0;
stats->sos = 0.0;
}
void update_stats(subframe_stats_t *stats, FLAC__int32 residual, unsigned incr)
{
unsigned i;
const double r = (double)residual, a = r*incr;
stats->nsamples += incr;
stats->sum += a;
stats->sos += (a*r);
for(i = 0; i < stats->nbuckets; i++) {
if(stats->buckets[i].residual == residual) {
stats->buckets[i].count += incr;
goto find_peak;
}
}
/* not found, make a new bucket */
i = stats->nbuckets;
stats->buckets[i].residual = residual;
stats->buckets[i].count = incr;
stats->nbuckets++;
find_peak:
if(stats->peak_index < 0 || stats->buckets[i].count > stats->buckets[stats->peak_index].count)
stats->peak_index = i;
}
void compute_stats(subframe_stats_t *stats)
{
stats->mean = stats->sum / (double)stats->nsamples;
stats->variance = (stats->sos - (stats->sum * stats->sum / stats->nsamples)) / stats->nsamples;
stats->stddev = sqrt(stats->variance);
}
FLAC__bool dump_stats(const subframe_stats_t *stats, const char *filename)
{
FILE *outfile;
unsigned i;
const double m = stats->mean;
const double s1 = stats->stddev, s2 = s1*2, s3 = s1*3, s4 = s1*4, s5 = s1*5, s6 = s1*6;
const double p = stats->buckets[stats->peak_index].count;
outfile = fopen(filename, "w");
if(0 == outfile) {
fprintf(stderr, "ERROR opening %s\n", filename);
return false;
}
fprintf(outfile, "plot '-' title 'PDF', '-' title 'mean' with impulses, '-' title '1-stddev' with histeps, '-' title '2-stddev' with histeps, '-' title '3-stddev' with histeps, '-' title '4-stddev' with histeps, '-' title '5-stddev' with histeps, '-' title '6-stddev' with histeps\n");
for(i = 0; i < stats->nbuckets; i++) {
fprintf(outfile, "%d %u\n", stats->buckets[i].residual, stats->buckets[i].count);
}
fprintf(outfile, "e\n");
fprintf(outfile, "%f %f\ne\n", stats->mean, p);
fprintf(outfile, "%f %f\n%f %f\ne\n", m-s1, p*0.8, m+s1, p*0.8);
fprintf(outfile, "%f %f\n%f %f\ne\n", m-s2, p*0.7, m+s2, p*0.7);
fprintf(outfile, "%f %f\n%f %f\ne\n", m-s3, p*0.6, m+s3, p*0.6);
fprintf(outfile, "%f %f\n%f %f\ne\n", m-s4, p*0.5, m+s4, p*0.5);
fprintf(outfile, "%f %f\n%f %f\ne\n", m-s5, p*0.4, m+s5, p*0.4);
fprintf(outfile, "%f %f\n%f %f\ne\n", m-s6, p*0.3, m+s6, p*0.3);
fprintf(outfile, "pause -1 'waiting...'\n");
fclose(outfile);
return true;
}
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