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change to support new sign-folded rice coding

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This commit is contained in:
Josh Coalson 2001-01-06 01:24:53 +00:00
parent 7efa1051c4
commit 197537585d
1 changed files with 19 additions and 22 deletions
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41
src/libFLAC/encoder.c
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@ -37,11 +37,6 @@
#endif #endif
#define max(x,y) ((x)>(y)?(x):(y)) #define max(x,y) ((x)>(y)?(x):(y))
#ifdef RICE_BITS
#undef RICE_BITS
#endif
#define RICE_BITS(value, parameter) (2 + (parameter) + (((unsigned)((value) < 0? -(value) : (value))) >> (parameter)))
typedef struct FLAC__EncoderPrivate { typedef struct FLAC__EncoderPrivate {
unsigned input_capacity; /* current size (in samples) of the signal and residual buffers */ unsigned input_capacity; /* current size (in samples) of the signal and residual buffers */
int32 *integer_signal[FLAC__MAX_CHANNELS]; /* the integer version of the input signal */ int32 *integer_signal[FLAC__MAX_CHANNELS]; /* the integer version of the input signal */
@ -678,7 +673,8 @@ bool encoder_process_subframes_(FLAC__Encoder *encoder, bool is_last_frame, cons
for(fixed_order = min_fixed_order; fixed_order <= max_fixed_order; fixed_order++) { for(fixed_order = min_fixed_order; fixed_order <= max_fixed_order; fixed_order++) {
if(fixed_residual_bits_per_sample[fixed_order] >= (real)frame_header->bits_per_sample) if(fixed_residual_bits_per_sample[fixed_order] >= (real)frame_header->bits_per_sample)
continue; /* don't even try */ continue; /* don't even try */
rice_parameter = (fixed_residual_bits_per_sample[fixed_order] > 0.0)? (unsigned)(fixed_residual_bits_per_sample[fixed_order]+0.5) : 0; /* 0.5 is for rounding, another 1.0 is to account for the signed->unsigned conversion during rice coding */
rice_parameter = (fixed_residual_bits_per_sample[fixed_order] > 0.0)? (unsigned)(fixed_residual_bits_per_sample[fixed_order]+1.5) : 0;
if(rice_parameter >= (1u << FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN)) if(rice_parameter >= (1u << FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN))
rice_parameter = (1u << FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN) - 1; rice_parameter = (1u << FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN) - 1;
candidate_bits = encoder_evaluate_fixed_subframe_(integer_signal[channel], encoder->guts->residual[!encoder->guts->best_residual], frame_header->blocksize, frame_header->bits_per_sample, fixed_order, rice_parameter, max_partition_order, &(encoder->guts->candidate_subframe)); candidate_bits = encoder_evaluate_fixed_subframe_(integer_signal[channel], encoder->guts->residual[!encoder->guts->best_residual], frame_header->blocksize, frame_header->bits_per_sample, fixed_order, rice_parameter, max_partition_order, &(encoder->guts->candidate_subframe));
@ -715,7 +711,8 @@ bool encoder_process_subframes_(FLAC__Encoder *encoder, bool is_last_frame, cons
lpc_residual_bits_per_sample = FLAC__lpc_compute_expected_bits_per_residual_sample(lpc_error[lpc_order-1], frame_header->blocksize); lpc_residual_bits_per_sample = FLAC__lpc_compute_expected_bits_per_residual_sample(lpc_error[lpc_order-1], frame_header->blocksize);
if(lpc_residual_bits_per_sample >= (real)frame_header->bits_per_sample) if(lpc_residual_bits_per_sample >= (real)frame_header->bits_per_sample)
continue; /* don't even try */ continue; /* don't even try */
rice_parameter = (lpc_residual_bits_per_sample > 0.0)? (unsigned)(lpc_residual_bits_per_sample+0.5) : 0; /* 0.5 is for rounding, another 1.0 is to account for the signed->unsigned conversion during rice coding */
rice_parameter = (lpc_residual_bits_per_sample > 0.0)? (unsigned)(lpc_residual_bits_per_sample+1.5) : 0;
if(rice_parameter >= (1u << FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN)) if(rice_parameter >= (1u << FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN))
rice_parameter = (1u << FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN) - 1; rice_parameter = (1u << FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN) - 1;
for(qlp_coeff_precision = min_qlp_coeff_precision; qlp_coeff_precision <= max_qlp_coeff_precision; qlp_coeff_precision++) { for(qlp_coeff_precision = min_qlp_coeff_precision; qlp_coeff_precision <= max_qlp_coeff_precision; qlp_coeff_precision++) {
@ -770,7 +767,7 @@ unsigned encoder_evaluate_constant_subframe_(const int32 signal, unsigned bits_p
subframe->type = FLAC__SUBFRAME_TYPE_CONSTANT; subframe->type = FLAC__SUBFRAME_TYPE_CONSTANT;
subframe->data.constant.value = signal; subframe->data.constant.value = signal;
return 8 + bits_per_sample; return FLAC__SUBFRAME_HEADER_TYPE_LEN + bits_per_sample;
} }
unsigned encoder_evaluate_fixed_subframe_(const int32 signal[], int32 residual[], unsigned blocksize, unsigned bits_per_sample, unsigned order, unsigned rice_parameter, unsigned max_partition_order, FLAC__SubframeHeader *subframe) unsigned encoder_evaluate_fixed_subframe_(const int32 signal[], int32 residual[], unsigned blocksize, unsigned bits_per_sample, unsigned order, unsigned rice_parameter, unsigned max_partition_order, FLAC__SubframeHeader *subframe)
@ -790,7 +787,7 @@ unsigned encoder_evaluate_fixed_subframe_(const int32 signal[], int32 residual[]
for(i = 0; i < order; i++) for(i = 0; i < order; i++)
subframe->data.fixed.warmup[i] = signal[i]; subframe->data.fixed.warmup[i] = signal[i];
return 8 + (order * bits_per_sample) + residual_bits; return FLAC__SUBFRAME_HEADER_TYPE_LEN + (order * bits_per_sample) + residual_bits;
} }
unsigned encoder_evaluate_lpc_subframe_(const int32 signal[], int32 residual[], const real lp_coeff[], unsigned blocksize, unsigned bits_per_sample, unsigned order, unsigned qlp_coeff_precision, unsigned rice_parameter, unsigned max_partition_order, FLAC__SubframeHeader *subframe) unsigned encoder_evaluate_lpc_subframe_(const int32 signal[], int32 residual[], const real lp_coeff[], unsigned blocksize, unsigned bits_per_sample, unsigned order, unsigned qlp_coeff_precision, unsigned rice_parameter, unsigned max_partition_order, FLAC__SubframeHeader *subframe)
@ -819,14 +816,14 @@ unsigned encoder_evaluate_lpc_subframe_(const int32 signal[], int32 residual[],
for(i = 0; i < order; i++) for(i = 0; i < order; i++)
subframe->data.lpc.warmup[i] = signal[i]; subframe->data.lpc.warmup[i] = signal[i];
return 8 + 9 + (order * (qlp_coeff_precision + bits_per_sample)) + residual_bits; return FLAC__SUBFRAME_HEADER_TYPE_LEN + FLAC__SUBFRAME_HEADER_LPC_QLP_COEFF_PRECISION_LEN + FLAC__SUBFRAME_HEADER_LPC_QLP_SHIFT_LEN + (order * (qlp_coeff_precision + bits_per_sample)) + residual_bits;
} }
unsigned encoder_evaluate_verbatim_subframe_(unsigned blocksize, unsigned bits_per_sample, FLAC__SubframeHeader *subframe) unsigned encoder_evaluate_verbatim_subframe_(unsigned blocksize, unsigned bits_per_sample, FLAC__SubframeHeader *subframe)
{ {
subframe->type = FLAC__SUBFRAME_TYPE_VERBATIM; subframe->type = FLAC__SUBFRAME_TYPE_VERBATIM;
return 8 + (blocksize * bits_per_sample); return FLAC__SUBFRAME_HEADER_TYPE_LEN + (blocksize * bits_per_sample);
} }
unsigned encoder_find_best_partition_order_(int32 residual[], unsigned residual_samples, unsigned predictor_order, unsigned rice_parameter, unsigned max_partition_order, unsigned *best_partition_order, unsigned best_parameters[]) unsigned encoder_find_best_partition_order_(int32 residual[], unsigned residual_samples, unsigned predictor_order, unsigned rice_parameter, unsigned max_partition_order, unsigned *best_partition_order, unsigned best_parameters[])
@ -887,19 +884,18 @@ void encoder_promote_candidate_subframe_(FLAC__Encoder *encoder)
bool encoder_set_partitioned_rice_(const int32 residual[], const unsigned residual_samples, const unsigned predictor_order, const unsigned rice_parameter, const unsigned partition_order, unsigned parameters[], unsigned *bits) bool encoder_set_partitioned_rice_(const int32 residual[], const unsigned residual_samples, const unsigned predictor_order, const unsigned rice_parameter, const unsigned partition_order, unsigned parameters[], unsigned *bits)
{ {
unsigned bits_ = 2 + 3; unsigned bits_ = FLAC__ENTROPY_CODING_METHOD_TYPE_LEN + FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_ORDER_LEN;
if(partition_order == 0) { if(partition_order == 0) {
unsigned i; unsigned i;
parameters[0] = rice_parameter; parameters[0] = rice_parameter;
bits_ += FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN; bits_ += FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN;
for(i = 0; i < residual_samples; i++) for(i = 0; i < residual_samples; i++)
bits_ += RICE_BITS(residual[i], rice_parameter); bits_ += FLAC__bitbuffer_rice_bits(residual[i], rice_parameter);
} }
else { else {
unsigned i, j, k = 0, k_last = 0, z; unsigned i, j, k = 0, k_last = 0;
unsigned mean; unsigned mean, parameter, partition_samples;
unsigned parameter, partition_samples;
const unsigned max_parameter = (1u << FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN) - 1; const unsigned max_parameter = (1u << FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN) - 1;
for(i = 0; i < (1u<<partition_order); i++) { for(i = 0; i < (1u<<partition_order); i++) {
partition_samples = (residual_samples+predictor_order) >> partition_order; partition_samples = (residual_samples+predictor_order) >> partition_order;
@ -913,17 +909,18 @@ bool encoder_set_partitioned_rice_(const int32 residual[], const unsigned residu
for(j = 0; j < partition_samples; j++, k++) for(j = 0; j < partition_samples; j++, k++)
mean += ((residual[k] < 0)? (unsigned)(-residual[k]) : (unsigned)residual[k]); mean += ((residual[k] < 0)? (unsigned)(-residual[k]) : (unsigned)residual[k]);
mean /= partition_samples; mean /= partition_samples;
z = 0x80000000; /* calc parameter = floor(log2(mean)) + 1 */
for(j = 0; j < 32; j++, z >>= 1) parameter = 0;
if(mean & z) while(mean) {
break; parameter++;
parameter = j > 31? 0 : 32 - j - 1; mean >>= 1;
}
if(parameter > max_parameter) if(parameter > max_parameter)
parameter = max_parameter; parameter = max_parameter;
parameters[i] = parameter; parameters[i] = parameter;
bits_ += FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN; bits_ += FLAC__ENTROPY_CODING_METHOD_PARTITIONED_RICE_PARAMETER_LEN;
for(j = k_last; j < k; j++) for(j = k_last; j < k; j++)
bits_ += RICE_BITS(residual[j], parameter); bits_ += FLAC__bitbuffer_rice_bits(residual[j], parameter);
k_last = k; k_last = k;
} }
} }