src/flac/analyze.c

   1 /* flac - Command-line FLAC encoder/decoder
   2  * Copyright (C) 2000,2001,2002,2003,2004,2005,2006  Josh Coalson
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  17  */
  18
  19 #if HAVE_CONFIG_H
  20 #  include <config.h>
  21 #endif
  22
  23 #include <errno.h>
  24 #include <math.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include "FLAC/all.h"
  29 #include "analyze.h"
  30
  31 typedef struct {
  32         FLAC__int32 residual;
  33         unsigned count;
  34 } pair_t;
  35
  36 typedef struct {
  37         pair_t buckets[FLAC__MAX_BLOCK_SIZE];
  38         int peak_index;
  39         unsigned nbuckets;
  40         unsigned nsamples;
  41         double sum, sos;
  42         double variance;
  43         double mean;
  44         double stddev;
  45 } subframe_stats_t;
  46
  47 static subframe_stats_t all_;
  48
  49 static void init_stats(subframe_stats_t *stats);
  50 static void update_stats(subframe_stats_t *stats, FLAC__int32 residual, unsigned incr);
  51 static void compute_stats(subframe_stats_t *stats);
  52 static FLAC__bool dump_stats(const subframe_stats_t *stats, const char *filename);
  53
  54 void flac__analyze_init(analysis_options aopts)
  55 {
  56         if(aopts.do_residual_gnuplot) {
  57                 init_stats(&all_);
  58         }
  59 }
  60
  61 void flac__analyze_frame(const FLAC__Frame *frame, unsigned frame_number, analysis_options aopts, FILE *fout)
  62 {
  63         const unsigned channels = frame->header.channels;
  64         char outfilename[1024];
  65         subframe_stats_t stats;
  66         unsigned i, channel;
  67
  68         /* do the human-readable part first */
  69         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]);
  70         for(channel = 0; channel < channels; channel++) {
  71                 const FLAC__Subframe *subframe = frame->subframes+channel;
  72                 fprintf(fout, "\tsubframe=%u\twasted_bits=%u\ttype=%s", channel, subframe->wasted_bits, FLAC__SubframeTypeString[subframe->type]);
  73                 switch(subframe->type) {
  74                         case FLAC__SUBFRAME_TYPE_CONSTANT:
  75                                 fprintf(fout, "\tvalue=%d\n", subframe->data.constant.value);
  76                                 break;
  77                         case FLAC__SUBFRAME_TYPE_FIXED:
  78                                 FLAC__ASSERT(subframe->data.fixed.entropy_coding_method.type == FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE);
  79                                 fprintf(fout, "\torder=%u\tpartition_order=%u\n", subframe->data.fixed.order, subframe->data.fixed.entropy_coding_method.data.partitioned_rice.order);
  80                                 for(i = 0; i < subframe->data.fixed.order; i++)
  81                                         fprintf(fout, "\t\twarmup[%u]=%d\n", i, subframe->data.fixed.warmup[i]);
  82                                 if(aopts.do_residual_text) {
  83                                         const unsigned partitions = (1u << subframe->data.fixed.entropy_coding_method.data.partitioned_rice.order);
  84                                         for(i = 0; i < partitions; i++) {
  85                                                 unsigned parameter = subframe->data.fixed.entropy_coding_method.data.partitioned_rice.contents->parameters[i];
  86                                                 if(parameter == FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ESCAPE_PARAMETER)
  87                                                         fprintf(fout, "\t\tparameter[%u]=ESCAPE, raw_bits=%u\n", i, subframe->data.fixed.entropy_coding_method.data.partitioned_rice.contents->raw_bits[i]);
  88                                                 else
  89                                                         fprintf(fout, "\t\tparameter[%u]=%u\n", i, parameter);
  90                                         }
  91                                         for(i = 0; i < frame->header.blocksize-subframe->data.fixed.order; i++)
  92                                                 fprintf(fout, "\t\tresidual[%u]=%d\n", i, subframe->data.fixed.residual[i]);
  93                                 }
  94                                 break;
  95                         case FLAC__SUBFRAME_TYPE_LPC:
  96                                 FLAC__ASSERT(subframe->data.lpc.entropy_coding_method.type == FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE);
  97                                 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);
  98                                 for(i = 0; i < subframe->data.lpc.order; i++)
  99                                         fprintf(fout, "\t\twarmup[%u]=%d\n", i, subframe->data.lpc.warmup[i]);
 100                                 if(aopts.do_residual_text) {
 101                                         const unsigned partitions = (1u << subframe->data.lpc.entropy_coding_method.data.partitioned_rice.order);
 102                                         for(i = 0; i < partitions; i++) {
 103                                                 unsigned parameter = subframe->data.lpc.entropy_coding_method.data.partitioned_rice.contents->parameters[i];
 104                                                 if(parameter == FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ESCAPE_PARAMETER)
 105                                                         fprintf(fout, "\t\tparameter[%u]=ESCAPE, raw_bits=%u\n", i, subframe->data.lpc.entropy_coding_method.data.partitioned_rice.contents->raw_bits[i]);
 106                                                 else
 107                                                         fprintf(fout, "\t\tparameter[%u]=%u\n", i, parameter);
 108                                         }
 109                                         for(i = 0; i < frame->header.blocksize-subframe->data.lpc.order; i++)
 110                                                 fprintf(fout, "\t\tresidual[%u]=%d\n", i, subframe->data.lpc.residual[i]);
 111                                 }
 112                                 break;
 113                         case FLAC__SUBFRAME_TYPE_VERBATIM:
 114                                 fprintf(fout, "\n");
 115                                 break;
 116                 }
 117         }
 118
 119         /* now do the residual distributions if requested */
 120         if(aopts.do_residual_gnuplot) {
 121                 for(channel = 0; channel < channels; channel++) {
 122                         const FLAC__Subframe *subframe = frame->subframes+channel;
 123                         unsigned residual_samples;
 124
 125                         init_stats(&stats);
 126
 127                         switch(subframe->type) {
 128                                 case FLAC__SUBFRAME_TYPE_FIXED:
 129                                         residual_samples = frame->header.blocksize - subframe->data.fixed.order;
 130                                         for(i = 0; i < residual_samples; i++)
 131                                                 update_stats(&stats, subframe->data.fixed.residual[i], 1);
 132                                         break;
 133                                 case FLAC__SUBFRAME_TYPE_LPC:
 134                                         residual_samples = frame->header.blocksize - subframe->data.lpc.order;
 135                                         for(i = 0; i < residual_samples; i++)
 136                                                 update_stats(&stats, subframe->data.lpc.residual[i], 1);
 137                                         break;
 138                                 default:
 139                                         break;
 140                         }
 141
 142                         /* update all_ */
 143                         for(i = 0; i < stats.nbuckets; i++) {
 144                                 update_stats(&all_, stats.buckets[i].residual, stats.buckets[i].count);
 145                         }
 146
 147                         /* write the subframe */
 148                         sprintf(outfilename, "f%06u.s%u.gp", frame_number, channel);
 149                         compute_stats(&stats);
 150
 151                         (void)dump_stats(&stats, outfilename);
 152                 }
 153         }
 154 }
 155
 156 void flac__analyze_finish(analysis_options aopts)
 157 {
 158         if(aopts.do_residual_gnuplot) {
 159                 compute_stats(&all_);
 160                 (void)dump_stats(&all_, "all");
 161         }
 162 }
 163
 164 void init_stats(subframe_stats_t *stats)
 165 {
 166         stats->peak_index = -1;
 167         stats->nbuckets = 0;
 168         stats->nsamples = 0;
 169         stats->sum = 0.0;
 170         stats->sos = 0.0;
 171 }
 172
 173 void update_stats(subframe_stats_t *stats, FLAC__int32 residual, unsigned incr)
 174 {
 175         unsigned i;
 176         const double r = (double)residual, a = r*incr;
 177
 178         stats->nsamples += incr;
 179         stats->sum += a;
 180         stats->sos += (a*r);
 181
 182         for(i = 0; i < stats->nbuckets; i++) {
 183                 if(stats->buckets[i].residual == residual) {
 184                         stats->buckets[i].count += incr;
 185                         goto find_peak;
 186                 }
 187         }
 188         /* not found, make a new bucket */
 189         i = stats->nbuckets;
 190         stats->buckets[i].residual = residual;
 191         stats->buckets[i].count = incr;
 192         stats->nbuckets++;
 193 find_peak:
 194         if(stats->peak_index < 0 || stats->buckets[i].count > stats->buckets[stats->peak_index].count)
 195                 stats->peak_index = i;
 196 }
 197
 198 void compute_stats(subframe_stats_t *stats)
 199 {
 200         stats->mean = stats->sum / (double)stats->nsamples;
 201         stats->variance = (stats->sos - (stats->sum * stats->sum / stats->nsamples)) / stats->nsamples;
 202         stats->stddev = sqrt(stats->variance);
 203 }
 204
 205 FLAC__bool dump_stats(const subframe_stats_t *stats, const char *filename)
 206 {
 207         FILE *outfile;
 208         unsigned i;
 209         const double m = stats->mean;
 210         const double s1 = stats->stddev, s2 = s1*2, s3 = s1*3, s4 = s1*4, s5 = s1*5, s6 = s1*6;
 211         const double p = stats->buckets[stats->peak_index].count;
 212
 213         outfile = fopen(filename, "w");
 214
 215         if(0 == outfile) {
 216                 fprintf(stderr, "ERROR opening %s: %s\n", filename, strerror(errno));
 217                 return false;
 218         }
 219
 220         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");
 221
 222         for(i = 0; i < stats->nbuckets; i++) {
 223                 fprintf(outfile, "%d %u\n", stats->buckets[i].residual, stats->buckets[i].count);
 224         }
 225         fprintf(outfile, "e\n");
 226
 227         fprintf(outfile, "%f %f\ne\n", stats->mean, p);
 228         fprintf(outfile, "%f %f\n%f %f\ne\n", m-s1, p*0.8, m+s1, p*0.8);
 229         fprintf(outfile, "%f %f\n%f %f\ne\n", m-s2, p*0.7, m+s2, p*0.7);
 230         fprintf(outfile, "%f %f\n%f %f\ne\n", m-s3, p*0.6, m+s3, p*0.6);
 231         fprintf(outfile, "%f %f\n%f %f\ne\n", m-s4, p*0.5, m+s4, p*0.5);
 232         fprintf(outfile, "%f %f\n%f %f\ne\n", m-s5, p*0.4, m+s5, p*0.4);
 233         fprintf(outfile, "%f %f\n%f %f\ne\n", m-s6, p*0.3, m+s6, p*0.3);
 234
 235         fprintf(outfile, "pause -1 'waiting...'\n");
 236
 237         fclose(outfile);
 238         return true;
 239 }