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Update qoa.h

pull/4439/head
Ray 1 month ago
parent
commit
d0e11a8c92
1 changed files with 53 additions and 39 deletions
  1. +53
    -39
      src/external/qoa.h

+ 53
- 39
src/external/qoa.h View File

@ -366,22 +366,7 @@ unsigned int qoa_encode_frame(const short *sample_data, qoa_desc *qoa, unsigned
), bytes, &p);
for (int c = 0; c < channels; c++) {
/* If the weights have grown too large, reset them to 0. This may happen
with certain high-frequency sounds. This is a last resort and will
introduce quite a bit of noise, but should at least prevent pops/clicks */
int weights_sum =
qoa->lms[c].weights[0] * qoa->lms[c].weights[0] +
qoa->lms[c].weights[1] * qoa->lms[c].weights[1] +
qoa->lms[c].weights[2] * qoa->lms[c].weights[2] +
qoa->lms[c].weights[3] * qoa->lms[c].weights[3];
if (weights_sum > 0x2fffffff) {
qoa->lms[c].weights[0] = 0;
qoa->lms[c].weights[1] = 0;
qoa->lms[c].weights[2] = 0;
qoa->lms[c].weights[3] = 0;
}
for (unsigned int c = 0; c < channels; c++) {
/* Write the current LMS state */
qoa_uint64_t weights = 0;
qoa_uint64_t history = 0;
@ -395,9 +380,9 @@ unsigned int qoa_encode_frame(const short *sample_data, qoa_desc *qoa, unsigned
/* We encode all samples with the channels interleaved on a slice level.
E.g. for stereo: (ch-0, slice 0), (ch 1, slice 0), (ch 0, slice 1), ...*/
for (int sample_index = 0; sample_index < frame_len; sample_index += QOA_SLICE_LEN) {
for (unsigned int sample_index = 0; sample_index < frame_len; sample_index += QOA_SLICE_LEN) {
for (int c = 0; c < channels; c++) {
for (unsigned int c = 0; c < channels; c++) {
int slice_len = qoa_clamp(QOA_SLICE_LEN, 0, frame_len - sample_index);
int slice_start = sample_index * channels + c;
int slice_end = (sample_index + slice_len) * channels + c;
@ -405,10 +390,13 @@ unsigned int qoa_encode_frame(const short *sample_data, qoa_desc *qoa, unsigned
/* Brute for search for the best scalefactor. Just go through all
16 scalefactors, encode all samples for the current slice and
meassure the total squared error. */
qoa_uint64_t best_error = -1;
qoa_uint64_t best_slice;
qoa_uint64_t best_rank = -1;
#ifdef QOA_RECORD_TOTAL_ERROR
qoa_uint64_t best_error = -1;
#endif
qoa_uint64_t best_slice = 0;
qoa_lms_t best_lms;
int best_scalefactor;
int best_scalefactor = 0;
for (int sfi = 0; sfi < 16; sfi++) {
/* There is a strong correlation between the scalefactors of
@ -421,7 +409,10 @@ unsigned int qoa_encode_frame(const short *sample_data, qoa_desc *qoa, unsigned
state when encoding. */
qoa_lms_t lms = qoa->lms[c];
qoa_uint64_t slice = scalefactor;
qoa_uint64_t current_error = 0;
qoa_uint64_t current_rank = 0;
#ifdef QOA_RECORD_TOTAL_ERROR
qoa_uint64_t current_error = 0;
#endif
for (int si = slice_start; si < slice_end; si += channels) {
int sample = sample_data[si];
@ -434,9 +425,27 @@ unsigned int qoa_encode_frame(const short *sample_data, qoa_desc *qoa, unsigned
int dequantized = qoa_dequant_tab[scalefactor][quantized];
int reconstructed = qoa_clamp_s16(predicted + dequantized);
/* If the weights have grown too large, we introduce a penalty
here. This prevents pops/clicks in certain problem cases */
int weights_penalty = ((
lms.weights[0] * lms.weights[0] +
lms.weights[1] * lms.weights[1] +
lms.weights[2] * lms.weights[2] +
lms.weights[3] * lms.weights[3]
) >> 18) - 0x8ff;
if (weights_penalty < 0) {
weights_penalty = 0;
}
long long error = (sample - reconstructed);
current_error += error * error;
if (current_error > best_error) {
qoa_uint64_t error_sq = error * error;
current_rank += error_sq + weights_penalty * weights_penalty;
#ifdef QOA_RECORD_TOTAL_ERROR
current_error += error_sq;
#endif
if (current_rank > best_rank) {
break;
}
@ -444,8 +453,11 @@ unsigned int qoa_encode_frame(const short *sample_data, qoa_desc *qoa, unsigned
slice = (slice << 3) | quantized;
}
if (current_error < best_error) {
best_error = current_error;
if (current_rank < best_rank) {
best_rank = current_rank;
#ifdef QOA_RECORD_TOTAL_ERROR
best_error = current_error;
#endif
best_slice = slice;
best_lms = lms;
best_scalefactor = scalefactor;
@ -490,7 +502,7 @@ void *qoa_encode(const short *sample_data, qoa_desc *qoa, unsigned int *out_len)
unsigned char *bytes = QOA_MALLOC(encoded_size);
for (int c = 0; c < qoa->channels; c++) {
for (unsigned int c = 0; c < qoa->channels; c++) {
/* Set the initial LMS weights to {0, 0, -1, 2}. This helps with the
prediction of the first few ms of a file. */
qoa->lms[c].weights[0] = 0;
@ -513,7 +525,7 @@ void *qoa_encode(const short *sample_data, qoa_desc *qoa, unsigned int *out_len)
#endif
int frame_len = QOA_FRAME_LEN;
for (int sample_index = 0; sample_index < qoa->samples; sample_index += frame_len) {
for (unsigned int sample_index = 0; sample_index < qoa->samples; sample_index += frame_len) {
frame_len = qoa_clamp(QOA_FRAME_LEN, 0, qoa->samples - sample_index);
const short *frame_samples = sample_data + sample_index * qoa->channels;
unsigned int frame_size = qoa_encode_frame(frame_samples, qoa, frame_len, bytes + p);
@ -576,14 +588,14 @@ unsigned int qoa_decode_frame(const unsigned char *bytes, unsigned int size, qoa
/* Read and verify the frame header */
qoa_uint64_t frame_header = qoa_read_u64(bytes, &p);
int channels = (frame_header >> 56) & 0x0000ff;
int samplerate = (frame_header >> 32) & 0xffffff;
int samples = (frame_header >> 16) & 0x00ffff;
int frame_size = (frame_header ) & 0x00ffff;
unsigned int channels = (frame_header >> 56) & 0x0000ff;
unsigned int samplerate = (frame_header >> 32) & 0xffffff;
unsigned int samples = (frame_header >> 16) & 0x00ffff;
unsigned int frame_size = (frame_header ) & 0x00ffff;
int data_size = frame_size - 8 - QOA_LMS_LEN * 4 * channels;
int num_slices = data_size / 8;
int max_total_samples = num_slices * QOA_SLICE_LEN;
unsigned int data_size = frame_size - 8 - QOA_LMS_LEN * 4 * channels;
unsigned int num_slices = data_size / 8;
unsigned int max_total_samples = num_slices * QOA_SLICE_LEN;
if (
channels != qoa->channels ||
@ -596,7 +608,7 @@ unsigned int qoa_decode_frame(const unsigned char *bytes, unsigned int size, qoa
/* Read the LMS state: 4 x 2 bytes history, 4 x 2 bytes weights per channel */
for (int c = 0; c < channels; c++) {
for (unsigned int c = 0; c < channels; c++) {
qoa_uint64_t history = qoa_read_u64(bytes, &p);
qoa_uint64_t weights = qoa_read_u64(bytes, &p);
for (int i = 0; i < QOA_LMS_LEN; i++) {
@ -609,17 +621,19 @@ unsigned int qoa_decode_frame(const unsigned char *bytes, unsigned int size, qoa
/* Decode all slices for all channels in this frame */
for (int sample_index = 0; sample_index < samples; sample_index += QOA_SLICE_LEN) {
for (int c = 0; c < channels; c++) {
for (unsigned int sample_index = 0; sample_index < samples; sample_index += QOA_SLICE_LEN) {
for (unsigned int c = 0; c < channels; c++) {
qoa_uint64_t slice = qoa_read_u64(bytes, &p);
int scalefactor = (slice >> 60) & 0xf;
slice <<= 4;
int slice_start = sample_index * channels + c;
int slice_end = qoa_clamp(sample_index + QOA_SLICE_LEN, 0, samples) * channels + c;
for (int si = slice_start; si < slice_end; si += channels) {
int predicted = qoa_lms_predict(&qoa->lms[c]);
int quantized = (slice >> 57) & 0x7;
int quantized = (slice >> 61) & 0x7;
int dequantized = qoa_dequant_tab[scalefactor][quantized];
int reconstructed = qoa_clamp_s16(predicted + dequantized);

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