shithub: aacenc

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cutoff frequency tuned to fully utilize top band; removed mid frequency boost (it turned out useless)

--- a/libfaac/aacquant.c

+++ b/libfaac/aacquant.c

@@ -101,7 +101,7 @@

     for (sb = 0; sb < coderInfo->nr_of_sfb; sb++)

         scale_factor[sb] = 0;

-    if (BlocQuant(coderInfo, xr, xi, (double)aacquantCfg->quality/DEFQUAL, aacquantCfg->pow43))

+    if (BlocQuant(coderInfo, xr, xi, aacquantCfg))

     {

         UpdateRequant(coderInfo, xi, aacquantCfg->pow43);

--- a/libfaac/aacquant.h

+++ b/libfaac/aacquant.h

@@ -36,13 +36,15 @@

 #define POW20(x)  pow(2.0,((double)x)*.25)

 #define IPOW20(x)  pow(2.0,-((double)x)*.1875)

-#pragma pack(push, 1)

 typedef struct

   {

     double *pow43;

     double quality;

+    int max_cbl;

+    int max_cbs;

   } AACQuantCfg;

-#pragma pack(pop)

+

+#include "quantize.h"

 enum {DEFQUAL = 100, MAXQUAL = 2000, MINQUAL = 10};

--- a/libfaac/frame.c

+++ b/libfaac/frame.c

@@ -262,6 +262,10 @@

     /* set quantization quality */

     hEncoder->aacquantCfg.quality = config->quantqual;

+    BandLimit(&hEncoder->config.bandWidth,

+              hEncoder->sampleRate,

+              hEncoder->srInfo,

+              &hEncoder->aacquantCfg);

     // reset psymodel

     hEncoder->psymodel->PsyEnd(&hEncoder->gpsyInfo, hEncoder->psyInfo, hEncoder->numChannels);

@@ -620,6 +624,7 @@

             hEncoder->overlapBuff[channel],

             MOVERLAPPED);

+#if 0

         if (coderInfo[channel].block_type == ONLY_SHORT_WINDOW) {

             for (k = 0; k < 8; k++) {

                 specFilter(hEncoder->freqBuff[channel]+k*BLOCK_LEN_SHORT,

@@ -629,6 +634,7 @@

             specFilter(hEncoder->freqBuff[channel], sampleRate,

 					bandWidth, BLOCK_LEN_LONG);

         }

+#endif

     }

     /* TMP: Build sfb offset table and other stuff */

--- a/libfaac/quantize.c

+++ b/libfaac/quantize.c

@@ -25,7 +25,7 @@

 // band sound masking

 static void bmask(CoderInfo *coderInfo, double *xr, double *bandqual,

-                  double quality)

+                  AACQuantCfg *aacquantCfg)

 {

   int sfb, start, end, cnt;

   int last = coderInfo->lastx;

@@ -33,9 +33,15 @@

   int *cb_offset = coderInfo->sfb_offset;

   int num_cb = coderInfo->nr_of_sfb;

   double avgenrg = coderInfo->avgenrg;

-  double powm = 0.25;

-  enum {MIDF=34};

+  double powm = 0.4;

+  int nullcb;

+  double quality = (double)aacquantCfg->quality/DEFQUAL;

+  if (coderInfo->block_type == ONLY_SHORT_WINDOW)

+      nullcb = aacquantCfg->max_cbs;

+  else

+      nullcb = aacquantCfg->max_cbl;

+

   for (sfb = 0; sfb < num_cb; sfb++)

   {

     if (last > cb_offset[sfb])

@@ -42,7 +48,7 @@

       lastsb = sfb;

   }

-  for (sfb = 0; sfb < num_cb; sfb++)

+  for (sfb = 0; sfb < nullcb; sfb++)

   {

     double avge, maxe;

     double target;

@@ -72,8 +78,6 @@

     {

         target = NOISETONE * pow(avge/avgenrg, powm);

         target += (1.0 - NOISETONE) * 0.45 * pow(maxe/avgenrg, powm);

-

-        target *= 0.9 + (40.0 / (fabs(start + end - MIDF) + 32));

     }

     else

     {

@@ -80,15 +84,17 @@

         target = NOISETONE * pow(avge/avgenrg, powm);

         target += (1.0 - NOISETONE) * 0.45 * pow(maxe/avgenrg, powm);

-        target *= 0.9 + (40.0 / (0.125 * fabs(start + end - (8*MIDF)) + 32));

-

         target *= 0.45;

     }

-    target *= 1.0 / (0.75 + ((double)(start+end)/last));

+    target *= 6.5 / (1.0 + ((double)(start+end)/last));

-    bandqual[sfb] = 5.5 * target * quality;

+    bandqual[sfb] = target * quality;

   }

+  for (; sfb < num_cb; sfb++)

+  {

+    bandqual[sfb] = 0;

+  }

 }

 // use band quality levels to quantize a block

@@ -160,7 +166,7 @@

     }

 }

-int BlocQuant(CoderInfo *coderInfo, double *xr, int *xi, double quality, double *pow43)

+int BlocQuant(CoderInfo *coderInfo, double *xr, int *xi, AACQuantCfg *aacquantCfg)

 {

     double bandlvl[MAX_SCFAC_BANDS];

     int cnt;

@@ -172,10 +178,41 @@

     SetMemory(xi, 0, FRAME_LEN*sizeof(xi[0]));

     if (nonzero)

     {

-        bmask(coderInfo, xr, bandlvl, quality);

-        qlevel(coderInfo, xr, xi, bandlvl, pow43);

+        bmask(coderInfo, xr, bandlvl, aacquantCfg);

+        qlevel(coderInfo, xr, xi, bandlvl, aacquantCfg->pow43);

         return 1;

     }

     return 0;

+}

+

+void BandLimit(unsigned *bw, int rate, SR_INFO *sr, AACQuantCfg *aacquantCfg)

+{

+    // find max short frame band

+    int max = *bw * (BLOCK_LEN_SHORT << 1) / rate;

+    int cnt;

+    int l;

+

+    l = 0;

+    for (cnt = 0; cnt < sr->num_cb_short; cnt++)

+    {

+        if (l >= max)

+            break;

+        l += sr->cb_width_short[cnt];

+    }

+    aacquantCfg->max_cbs = cnt;

+    *bw = (double)l * rate / (BLOCK_LEN_SHORT << 1);

+

+    // find max long frame band

+    max = *bw * (BLOCK_LEN_LONG << 1) / rate;

+    l = 0;

+    for (cnt = 0; cnt < sr->num_cb_long; cnt++)

+    {

+        if (l >= max)

+            break;

+        l += sr->cb_width_long[cnt];

+    }

+    aacquantCfg->max_cbl = cnt;

+

+    *bw = (double)l * rate / (BLOCK_LEN_LONG << 1);

 }