Useful util while I beef up psychoacoustics.

svn path=/trunk/vorbis/; revision=275

diff --git a/lib/psytune.c b/lib/psytune.c
new file mode 100644 (file)
index 0000000..e8ab52e
--- /dev/null
+++ b/lib/psytune.c
@@ -0,0 +1,141 @@
+/********************************************************************
+ *                                                                  *
+ * THIS FILE IS PART OF THE Ogg Vorbis SOFTWARE CODEC SOURCE CODE.  *
+ * USE, DISTRIBUTION AND REPRODUCTION OF THIS SOURCE IS GOVERNED BY *
+ * THE GNU PUBLIC LICENSE 2, WHICH IS INCLUDED WITH THIS SOURCE.    *
+ * PLEASE READ THESE TERMS DISTRIBUTING.                            *
+ *                                                                  *
+ * THE OggSQUISH SOURCE CODE IS (C) COPYRIGHT 1994-2000             *
+ * by Monty <monty@xiph.org> and The XIPHOPHORUS Company            *
+ * http://www.xiph.org/                                             *
+ *                                                                  *
+ ********************************************************************
+
+ function: simple utility that runs audio through the psychoacoustics
+           without encoding
+ last mod: $Id: psytune.c,v 1.1 2000/02/25 11:05:32 xiphmont Exp $
+
+ ********************************************************************/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+
+#include "vorbis/codec.h"
+#include "psy.h"
+#include "mdct.h"
+#include "window.h"
+
+static vorbis_info_psy _psy_set0={
+  {-20, -20, -14, -14, -14, -14, -14, -14, -14, -14,
+   -14, -14, -16, -16, -16, -16, -18, -18, -16, -16,
+   -12, -10, -6, -3, -1, -1, -0}, 0., (.6/1024), 10,4
+};
+
+int main(int argc,char *argv[]){
+  int eos=0;
+  double acc=0.;
+  double tot=0.;
+  int framesize=argv[1]?atoi(argv[1]):2048;
+  double *pcm[2],*out[2],*window,*mask,*decay[2];
+  signed char *buffer,*buffer2;
+  mdct_lookup m_look;
+  vorbis_look_psy p_look;
+
+  pcm[0]=malloc(framesize*sizeof(double));
+  pcm[1]=malloc(framesize*sizeof(double));
+  out[0]=calloc(framesize/2,sizeof(double));
+  out[1]=calloc(framesize/2,sizeof(double));
+  decay[0]=calloc(framesize/2,sizeof(double));
+  decay[1]=calloc(framesize/2,sizeof(double));
+  mask=malloc(framesize/2*sizeof(double));
+  buffer=malloc(framesize*4);
+  buffer2=buffer+framesize*2;
+  window=_vorbis_window(0,framesize,framesize/2,framesize/2);
+  mdct_init(&m_look,framesize);
+  _vp_psy_init(&p_look,&_psy_set0,framesize/2,44100);
+
+  /* we cheat on the WAV header; we just bypass 44 bytes and never
+     verify that it matches 16bit/stereo/44.1kHz. */
+  
+  fread(buffer,1,44,stdin);
+  fwrite(buffer,1,44,stdout);
+  memset(buffer,0,framesize*2);
+
+  fprintf(stderr,"Processing for frame size %d...\n",framesize);
+
+  while(!eos){
+    long i,j,k;
+    long bytes=fread(buffer2,1,framesize*2,stdin); 
+    if(bytes<framesize*2)
+      memset(buffer2+bytes,0,framesize*2-bytes);
+    
+    if(bytes!=0){
+
+      /* uninterleave samples */
+      for(i=0;i<framesize;i++){
+        pcm[0][i]=((buffer[i*4+1]<<8)|
+                      (0x00ff&(int)buffer[i*4]))/32768.;
+        pcm[1][i]=((buffer[i*4+3]<<8)|
+                  (0x00ff&(int)buffer[i*4+2]))/32768.;
+      }
+      
+      for(i=0;i<2;i++){
+       for(j=0;j<framesize;j++)
+         pcm[i][j]*=window[j];
+
+       mdct_forward(&m_look,pcm[i],pcm[i]);
+
+       /* do the psychacoustics */
+
+       memset(mask,0,sizeof(double)*framesize/2);
+       _vp_mask_floor(&p_look,pcm[i],mask,decay[i],1);
+
+       /* quantize according to masking */
+       for(j=0;j<framesize/2;j++){
+         double val;
+         if(mask[j]==0)
+           val=0;
+         else
+           val=rint(pcm[i][j]/mask[j]);
+         acc+=log(fabs(val)*2.+1.)/log(2);
+         tot++;
+         pcm[i][j]=val*mask[j];
+       }
+
+       /* take it back to time */
+       mdct_backward(&m_look,pcm[i],pcm[i]);
+       for(j=0;j<framesize/2;j++)
+         out[i][j]+=pcm[i][j]*window[j];
+      }
+           
+      /* write data.  Use the part of buffer we're about to shift out */
+      for(i=0;i<2;i++){
+       char *ptr=buffer+i*2;
+       double  *mono=out[i];
+       for(j=0;j<framesize/2;j++){
+         int val=mono[j]*32767.;
+         /* might as well guard against clipping */
+         if(val>32767)val=32767;
+         if(val<-32768)val=-32768;
+         ptr[0]=val&0xff;
+         ptr[1]=(val>>8)&0xff;
+         ptr+=4;
+       }
+      }
+ 
+      fwrite(buffer,1,framesize*2,stdout);
+      memmove(buffer,buffer2,framesize*2);
+
+      for(i=0;i<2;i++){
+       for(j=0,k=framesize/2;j<framesize/2;j++,k++)
+         out[i][j]=pcm[i][k]*window[k];
+      }
+    }else
+      eos=1;
+  }
+  fprintf(stderr,"average raw bits of entropy: %.03g/sample\n",acc/tot);
+  fprintf(stderr,"Done\n\n");
+  return 0;
+}