ref: 991c0f0254426e67f2f7938876001acca31cb5dd
parent: da72188b188f65158ce56421ea9153b8c5fd133d
author: Jean-Marc Valin <[email protected]>
date: Fri Nov 30 11:07:46 EST 2007
Code for computing band energies and normalising: adapted from CEFT.
--- a/libcelt/Makefile.am
+++ b/libcelt/Makefile.am
@@ -9,13 +9,14 @@
lib_LTLIBRARIES = libcelt.la
# Sources for compilation in the library
-libcelt_la_SOURCES = celt.c fftwrap.c mdct.c pitch.c smallft.c
+libcelt_la_SOURCES = bands.c celt.c fftwrap.c mdct.c pitch.c smallft.c
#noinst_HEADERS =
libcelt_la_LDFLAGS = -version-info @CELT_LT_CURRENT@:@CELT_LT_REVISION@:@CELT_LT_AGE@
-noinst_HEADERS = arch.h celt.h fftwrap.h mdct.h os_support.h pitch.h smallft.h
+noinst_HEADERS = arch.h bands.h celt.h fftwrap.h mdct.h os_support.h pitch.h \
+ smallft.h
noinst_PROGRAMS = testcelt
testcelt_SOURCES = testcelt.c
--- /dev/null
+++ b/libcelt/bands.c
@@ -1,0 +1,115 @@
+/* (C) 2007 Jean-Marc Valin, CSIRO
+*/
+/*
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions
+ are met:
+
+ - Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+
+ - Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in the
+ documentation and/or other materials provided with the distribution.
+
+ - Neither the name of the Xiph.org Foundation nor the names of its
+ contributors may be used to endorse or promote products derived from
+ this software without specific prior written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR
+ CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#include <math.h>
+#include "bands.h"
+
+const int qbank[NBANDS+2] = {0, 2, 4, 6, 8, 12, 16, 20, 24, 28, 36, 44, 52, 68, 84, 116, 128};+
+
+/* Compute the energy in each of the bands */
+void compute_bands(float *X, int B, float *bank)
+{+ int i;
+ for (i=0;i<NBANDS;i++)
+ {+ int j;
+ bank[i] = 1e-10;
+ for (j=B*qbank[i];j<B*qbank[i+1];j++)
+ bank[i] += X[j]*X[j];
+ bank[i] = sqrt(bank[i]);
+ }
+}
+
+/* Normalise each band such that the energy is one. */
+void normalise_bands(float *X, int B, float *bank)
+{+ int i;
+ for (i=0;i<NBANDS;i++)
+ {+ int j;
+ float x = 1.f/bank[i];
+ for (j=B*qbank[i];j<B*qbank[i+1];j++)
+ X[j] *= x;
+ }
+ for (i=B*qbank[NBANDS];i<B*qbank[NBANDS+1];i++)
+ X[i] = 0;
+}
+
+/* De-normalise the energy to produce the synthesis from the unit-energy bands */
+void denormalise_bands(float *X, int B, float *bank)
+{+ int i;
+ for (i=0;i<NBANDS;i++)
+ {+ int j;
+ float x = bank[i];
+ for (j=B*qbank[i];j<B*qbank[i+1];j++)
+ X[j] *= x;
+ }
+ for (i=B*qbank[NBANDS];i<B*qbank[NBANDS+1];i++)
+ X[i] = 0;
+}
+
+
+/* Scales the pulse-codebook entry in each band such that unit-energy is conserved when
+ adding the pitch */
+void pitch_renormalise_bands(float *X, int B, float *P)
+{+ int i;
+ for (i=0;i<NBANDS;i++)
+ {+ int j;
+ float Rpp=0;
+ float Rxp=0;
+ float Rxx=0;
+ float gain1;
+ for (j=B*qbank[i];j<B*qbank[i+1];j++)
+ {+ Rxp += X[j]*P[j];
+ Rpp += P[j]*P[j];
+ Rxx += X[j]*X[j];
+ }
+ float arg = Rxp*Rxp + 1 - Rpp;
+ gain1 = sqrt(arg)-Rxp;
+ if (Rpp>.9999)
+ Rpp = .9999;
+ Rxx = 0;
+ for (j=B*qbank[i];j<B*qbank[i+1];j++)
+ {+ X[j*2-1] = P[j]+gain1*X[j];
+ Rxx += X[j]*X[j];
+ }
+ }
+ for (i=B*qbank[NBANDS];i<B*qbank[NBANDS+1];i++)
+ X[i] = 0;
+}
+
--- /dev/null
+++ b/libcelt/bands.h
@@ -1,0 +1,45 @@
+/* (C) 2007 Jean-Marc Valin, CSIRO
+*/
+/*
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions
+ are met:
+
+ - Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+
+ - Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in the
+ documentation and/or other materials provided with the distribution.
+
+ - Neither the name of the Xiph.org Foundation nor the names of its
+ contributors may be used to endorse or promote products derived from
+ this software without specific prior written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR
+ CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#ifndef BANDS_H
+#define BANDS_H
+
+#define NBANDS 15
+
+void compute_bands(float *X, int B, float *bands);
+
+void normalise_bands(float *X, int B, float *bands);
+
+void denormalise_bands(float *X, int B, float *bands);
+
+void pitch_renormalise_bands(float *X, int B, float *P);
+
+#endif /* BANDS_H */
--- a/libcelt/celt.c
+++ b/libcelt/celt.c
@@ -35,6 +35,7 @@
#include "celt.h"
#include "pitch.h"
#include "fftwrap.h"
+#include "bands.h"
#define MAX_PERIOD 1024
@@ -53,6 +54,9 @@
float *in_mem;
float *mdct_overlap;
float *out_mem;
+
+ float *bandE;
+
};
@@ -74,7 +78,7 @@
st->in_mem = celt_alloc(N*sizeof(float));
st->mdct_overlap = celt_alloc(N*sizeof(float));
st->out_mem = celt_alloc(MAX_PERIOD*sizeof(float));
-
+ st->bandE = celt_alloc(NBANDS*sizeof(float));
for (i=0;i<N;i++)
st->window[i] = st->window[2*N-i-1] = sin(.5*M_PI* sin(.5*M_PI*(i+.5)/N) * sin(.5*M_PI*(i+.5)/N));
return st;
@@ -94,6 +98,9 @@
celt_free(st->in_mem);
celt_free(st->mdct_overlap);
celt_free(st->out_mem);
+
+ celt_free(st->bandE);
+
celt_free(st);
}
@@ -121,8 +128,9 @@
N = st->block_size;
B = st->nb_blocks;
float in[(B+1)*N];
- float X[B*N];
- float P[B*N];
+
+ float X[B*N]; /**< Interleaved signal MDCTs */
+ float P[B*N]; /**< Interleaved pitch MDCTs*/
int pitch_index;
/* FIXME: Add preemphasis */
@@ -156,6 +164,11 @@
printf ("\n");*//* Band normalisation */
+ compute_bands(X, B, st->bandE);
+ normalise_bands(X, B, st->bandE);
+
+ compute_bands(P, B, st->bandE);
+ normalise_bands(P, B, st->bandE);
/* Pitch prediction */
@@ -162,6 +175,7 @@
/* Residual quantisation */
/* Synthesis */
+ denormalise_bands(X, B, st->bandE);
CELT_MOVE(st->out_mem, st->out_mem+B*N, MAX_PERIOD-B*N);
/* Compute inverse MDCTs */