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temporary commit

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This commit is contained in:
Josh Coalson
2001-03-21 00:57:58 +00:00
parent bd82959b1d
commit 57a6a343bd
3 changed files with 189 additions and 12 deletions
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51
src/libFLAC/encoder.c
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@@ -1054,19 +1054,45 @@ unsigned encoder_find_best_partition_order_(const int32 residual[], uint32 abs_r
return best_residual_bits;
}
static unsigned iilog2_(unsigned v)
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;
assert(v > 0);
while(v >>= 1)
while(v) {
l++;
v >>= 1;
}
return l;
}
const double smult = 3.0;
const unsigned rpdec = 0;
static uint32 get_thresh_(const int32 residual[], const unsigned residual_samples)
{
double sum, sos, r, stddev, mean;
const double smult = 2.0;
unsigned i;
uint32 thresh;
@@ -1079,7 +1105,7 @@ static uint32 get_thresh_(const int32 residual[], const unsigned residual_sample
mean = sum / residual_samples;
stddev = sqrt((sos - (sum * sum / residual_samples)) / (residual_samples-1));
thresh = mean+smult*stddev;
thresh = iilog2_(thresh);
thresh = (1u << uilog21_(thresh)) - 1;
return thresh;
}
@@ -1094,11 +1120,10 @@ bool encoder_set_partitioned_rice_(const int32 residual[], const uint32 abs_resi
if(partition_order == 0) {
unsigned i;
#ifdef SYMMETRIC_RICE
uint32 thresh = get_thresh_(residual, residual_samples);
const unsigned rpdec = 1;
bool cross = false;
#ifdef SYMMETRIC_RICE
for(i=0;i<residual_samples;i++) {
if(abs_residual[i] >= thresh) {
cross = true;
@@ -1124,10 +1149,16 @@ bool encoder_set_partitioned_rice_(const int32 residual[], const uint32 abs_resi
for(i = 0; i < residual_samples; i++) {
#ifdef VARIABLE_RICE_BITS
#ifdef SYMMETRIC_RICE
if(cross && abs_residual[i] >= thresh)
bits_ += VARIABLE_RICE_BITS(0, rice_parameter) + 5 + iilog2_(abs_residual) + 1;
else
if(cross) {
unsigned escbits, normbits;
escbits = /* VARIABLE_RICE_BITS(0, rice_parameter) == 0 */ 5 + silog21_(residual[i]);
normbits = VARIABLE_RICE_BITS(abs_residual[i], rice_parameter);
bits += min(escbits, normbits);
}
else {
/*@@@ old way */
bits_ += VARIABLE_RICE_BITS(abs_residual[i], rice_parameter);
}
#else
bits_ += VARIABLE_RICE_BITS(abs_residual[i], rice_parameter_estimate);
#endif