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drop the escape-code stuff

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Josh Coalson
2001-03-21 22:53:43 +00:00
parent 8de897c9f9
commit 3b5f471837
2 changed files with 8 additions and 181 deletions
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88
src/libFLAC/encoder_framing.c
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@@ -19,7 +19,6 @@
#include <assert.h>
#include <stdio.h>
#include <math.h>
#include "private/encoder_framing.h"
#include "private/crc.h"
@@ -320,100 +319,17 @@ bool subframe_add_entropy_coding_method_(FLAC__BitBuffer *bb, const FLAC__Entrop
return true;
}
static unsigned silog21_(int v)
{
doit_:
if(v == 0) {
return 0;
}
else if(v > 0) {
unsigned l = 0;
while(v) {
l++;
v >>= 1;
}
return l+1;
}
else if(v == -1) {
return 2;
}
else {
v = -(++v);
goto doit_;
}
}
static unsigned uilog21_(unsigned v)
{
unsigned l = 0;
while(v) {
l++;
v >>= 1;
}
return l;
}
extern const double smult;
static uint32 get_thresh_(const int32 residual[], const unsigned residual_samples)
{
double sum, sos, r, stddev, mean;
unsigned i;
uint32 thresh;
sum = sos = 0.0;
for(i = 0; i < residual_samples; i++) {
r = (double)residual[i];
sum += r;
sos += r*r;
}
mean = sum / residual_samples;
stddev = sqrt((sos - (sum * sum / residual_samples)) / (residual_samples-1));
thresh = mean+smult*stddev;
thresh = (1u << uilog21_(thresh)) - 1;
return thresh;
}
bool subframe_add_residual_partitioned_rice_(FLAC__BitBuffer *bb, const int32 residual[], const unsigned residual_samples, const unsigned predictor_order, const unsigned rice_parameters[], const unsigned partition_order)
{
if(partition_order == 0) {
unsigned i;
#ifdef SYMMETRIC_RICE
uint32 thresh = get_thresh_(residual, residual_samples);
bool cross = false;
for(i=0;i<residual_samples;i++) {
uint32 a = (residual[i] < 0? -residual[i] : residual[i]);
if(a >= thresh) {
cross = true;
break;
}
}
#endif
if(!FLAC__bitbuffer_write_raw_uint32(bb, rice_parameters[0], FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN))
return false;
for(i = 0; i < residual_samples; i++) {
#ifdef SYMMETRIC_RICE
if(cross) {
unsigned escbits, normbits;
uint32 a = (residual[i] < 0? -residual[i] : residual[i]);
escbits = 5 + silog21_(residual[i]);
normbits = a >> rice_parameters[0];
if(escbits < normbits) {
fprintf(stderr,"ESCAPE, k=%u, r=%d, escbits=%u, normbits=%u, saved %u bits\n", rice_parameters[0], residual[i], escbits, normbits, normbits-escbits);
if(!FLAC__bitbuffer_write_symmetric_rice_signed_escape(bb, residual[i], rice_parameters[0]))
return false;
}
else {
if(!FLAC__bitbuffer_write_symmetric_rice_signed(bb, residual[i], rice_parameters[0]))
return false;
}
}
else {
if(!FLAC__bitbuffer_write_symmetric_rice_signed(bb, residual[i], rice_parameters[0]))
return false;
}
if(!FLAC__bitbuffer_write_symmetric_rice_signed(bb, residual[i], rice_parameters[0]))
return false;
#else
if(!FLAC__bitbuffer_write_rice_signed(bb, residual[i], rice_parameters[0]))
return false;