* FLAC audio encoder
* Copyright (c) 2006 Justin Ruggles <jruggle@earthlink.net>
*
- * This library is free software; you can redistribute it and/or
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
- * version 2 of the License, or (at your option) any later version.
+ * version 2.1 of the License, or (at your option) any later version.
*
- * This library is distributed in the hope that it will be useful,
+ * FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
+ * License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avcodec.h"
#include "bitstream.h"
#include "crc.h"
+#include "dsputil.h"
#include "golomb.h"
+#include "lls.h"
#define FLAC_MAX_CH 8
#define FLAC_MIN_BLOCKSIZE 16
#define ORDER_METHOD_4LEVEL 2
#define ORDER_METHOD_8LEVEL 3
#define ORDER_METHOD_SEARCH 4
+#define ORDER_METHOD_LOG 5
#define FLAC_STREAMINFO_SIZE 34
int shift;
RiceContext rc;
int32_t samples[FLAC_MAX_BLOCKSIZE];
- int32_t residual[FLAC_MAX_BLOCKSIZE];
+ int32_t residual[FLAC_MAX_BLOCKSIZE+1];
} FlacSubframe;
typedef struct FlacFrame {
FlacFrame frame;
CompressionOptions options;
AVCodecContext *avctx;
+ DSPContext dsp;
} FlacEncodeContext;
static const int flac_samplerates[16] = {
s->avctx = avctx;
+ dsputil_init(&s->dsp, avctx);
+
if(avctx->sample_fmt != SAMPLE_FMT_S16) {
return -1;
}
av_log(avctx, AV_LOG_DEBUG, " compression: %d\n", s->options.compression_level);
level= s->options.compression_level;
- if(level > 5) {
+ if(level > 12) {
av_log(avctx, AV_LOG_ERROR, "invalid compression level: %d\n",
s->options.compression_level);
return -1;
}
- s->options.block_time_ms = ((int[]){ 27, 27, 27,105,105,105})[level];
- s->options.use_lpc = ((int[]){ 0, 0, 0, 1, 1, 1})[level];
- s->options.min_prediction_order= ((int[]){ 2, 0, 0, 1, 1, 1})[level];
- s->options.max_prediction_order= ((int[]){ 3, 4, 4, 6, 8, 8})[level];
- s->options.prediction_order_method = ORDER_METHOD_EST;
- s->options.min_partition_order = ((int[]){ 2, 2, 0, 0, 0, 0})[level];
- s->options.max_partition_order = ((int[]){ 2, 2, 3, 3, 3, 8})[level];
+ s->options.block_time_ms = ((int[]){ 27, 27, 27,105,105,105,105,105,105,105,105,105,105})[level];
+ s->options.use_lpc = ((int[]){ 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1})[level];
+ s->options.min_prediction_order= ((int[]){ 2, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1})[level];
+ s->options.max_prediction_order= ((int[]){ 3, 4, 4, 6, 8, 8, 8, 8, 12, 12, 12, 32, 32})[level];
+ s->options.prediction_order_method = ((int[]){ ORDER_METHOD_EST, ORDER_METHOD_EST, ORDER_METHOD_EST,
+ ORDER_METHOD_EST, ORDER_METHOD_EST, ORDER_METHOD_EST,
+ ORDER_METHOD_4LEVEL, ORDER_METHOD_LOG, ORDER_METHOD_4LEVEL,
+ ORDER_METHOD_LOG, ORDER_METHOD_SEARCH, ORDER_METHOD_LOG,
+ ORDER_METHOD_SEARCH})[level];
+ s->options.min_partition_order = ((int[]){ 2, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0})[level];
+ s->options.max_partition_order = ((int[]){ 2, 2, 3, 3, 3, 8, 8, 8, 8, 8, 8, 8, 8})[level];
/* set compression option overrides from AVCodecContext */
if(avctx->use_lpc >= 0) {
- s->options.use_lpc = !!avctx->use_lpc;
+ s->options.use_lpc = av_clip(avctx->use_lpc, 0, 11);
}
- av_log(avctx, AV_LOG_DEBUG, " use lpc: %s\n",
- s->options.use_lpc? "yes" : "no");
+ if(s->options.use_lpc == 1)
+ av_log(avctx, AV_LOG_DEBUG, " use lpc: Levinson-Durbin recursion with Welch window\n");
+ else if(s->options.use_lpc > 1)
+ av_log(avctx, AV_LOG_DEBUG, " use lpc: Cholesky factorization\n");
if(avctx->min_prediction_order >= 0) {
if(s->options.use_lpc) {
s->options.min_prediction_order, s->options.max_prediction_order);
if(avctx->prediction_order_method >= 0) {
- if(avctx->prediction_order_method > ORDER_METHOD_SEARCH) {
+ if(avctx->prediction_order_method > ORDER_METHOD_LOG) {
av_log(avctx, AV_LOG_ERROR, "invalid prediction order method: %d\n",
avctx->prediction_order_method);
return -1;
}
s->options.prediction_order_method = avctx->prediction_order_method;
}
- switch(avctx->prediction_order_method) {
+ switch(s->options.prediction_order_method) {
case ORDER_METHOD_EST: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
"estimate"); break;
case ORDER_METHOD_2LEVEL: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
"8-level"); break;
case ORDER_METHOD_SEARCH: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
"full search"); break;
+ case ORDER_METHOD_LOG: av_log(avctx, AV_LOG_DEBUG, " order method: %s\n",
+ "log search"); break;
}
if(avctx->min_partition_order >= 0) {
if(avctx->frame_size > 0) {
if(avctx->frame_size < FLAC_MIN_BLOCKSIZE ||
- avctx->frame_size > FLAC_MIN_BLOCKSIZE) {
+ avctx->frame_size > FLAC_MAX_BLOCKSIZE) {
av_log(avctx, AV_LOG_ERROR, "invalid block size: %d\n",
avctx->frame_size);
return -1;
#define rice_encode_count(sum, n, k) (((n)*((k)+1))+((sum-(n>>1))>>(k)))
+/**
+ * Solve for d/dk(rice_encode_count) = n-((sum-(n>>1))>>(k+1)) = 0
+ */
static int find_optimal_param(uint32_t sum, int n)
{
- int k, k_opt;
- uint32_t nbits[MAX_RICE_PARAM+1];
-
- k_opt = 0;
- nbits[0] = UINT32_MAX;
- for(k=0; k<=MAX_RICE_PARAM; k++) {
- nbits[k] = rice_encode_count(sum, n, k);
- if(nbits[k] < nbits[k_opt]) {
- k_opt = k;
- }
- }
- return k_opt;
+ int k;
+ uint32_t sum2;
+
+ if(sum <= n>>1)
+ return 0;
+ sum2 = sum-(n>>1);
+ k = av_log2(n<256 ? FASTDIV(sum2,n) : sum2/n);
+ return FFMIN(k, MAX_RICE_PARAM);
}
static uint32_t calc_optimal_rice_params(RiceContext *rc, int porder,
uint32_t all_bits;
part = (1 << porder);
- all_bits = 0;
+ all_bits = 4 * part;
cnt = (n >> porder) - pred_order;
for(i=0; i<part; i++) {
- if(i == 1) cnt = (n >> porder);
k = find_optimal_param(sums[i], cnt);
rc->params[i] = k;
all_bits += rice_encode_count(sums[i], cnt, k);
+ cnt = n >> porder;
}
- all_bits += (4 * part);
rc->porder = porder;
res = &data[pred_order];
res_end = &data[n >> pmax];
for(i=0; i<parts; i++) {
- sums[pmax][i] = 0;
+ uint32_t sum = 0;
while(res < res_end){
- sums[pmax][i] += *(res++);
+ sum += *(res++);
}
+ sums[pmax][i] = sum;
res_end+= n >> pmax;
}
/* sums for lower levels */
return bits[opt_porder];
}
+static int get_max_p_order(int max_porder, int n, int order)
+{
+ int porder = FFMIN(max_porder, av_log2(n^(n-1)));
+ if(order > 0)
+ porder = FFMIN(porder, av_log2(n/order));
+ return porder;
+}
+
static uint32_t calc_rice_params_fixed(RiceContext *rc, int pmin, int pmax,
int32_t *data, int n, int pred_order,
int bps)
{
uint32_t bits;
+ pmin = get_max_p_order(pmin, n, pred_order);
+ pmax = get_max_p_order(pmax, n, pred_order);
bits = pred_order*bps + 6;
bits += calc_rice_params(rc, pmin, pmax, data, n, pred_order);
return bits;
int bps, int precision)
{
uint32_t bits;
+ pmin = get_max_p_order(pmin, n, pred_order);
+ pmax = get_max_p_order(pmax, n, pred_order);
bits = pred_order*bps + 4 + 5 + pred_order*precision + 6;
bits += calc_rice_params(rc, pmin, pmax, data, n, pred_order);
return bits;
* Calculates autocorrelation data from audio samples
* A Welch window function is applied before calculation.
*/
-static void compute_autocorr(const int32_t *data, int len, int lag,
- double *autoc)
+void ff_flac_compute_autocorr(const int32_t *data, int len, int lag,
+ double *autoc)
{
- int i;
- double *data1;
- int lag_ptr, ptr;
+ int i, j;
+ double tmp[len + lag + 1];
+ double *data1= tmp + lag;
- data1 = av_malloc(len * sizeof(double));
apply_welch_window(data, len, data1);
- for(i=0; i<lag; i++) autoc[i] = 1.0;
+ for(j=0; j<lag; j++)
+ data1[j-lag]= 0.0;
+ data1[len] = 0.0;
- ptr = 0;
- while(ptr <= lag) {
- lag_ptr = 0;
- while(lag_ptr <= ptr) {
- autoc[ptr-lag_ptr] += data1[ptr] * data1[lag_ptr];
- lag_ptr++;
+ for(j=0; j<lag; j+=2){
+ double sum0 = 1.0, sum1 = 1.0;
+ for(i=0; i<len; i++){
+ sum0 += data1[i] * data1[i-j];
+ sum1 += data1[i] * data1[i-j-1];
}
- ptr++;
+ autoc[j ] = sum0;
+ autoc[j+1] = sum1;
}
- while(ptr < len) {
- lag_ptr = ptr - lag;
- while(lag_ptr <= ptr) {
- autoc[ptr-lag_ptr] += data1[ptr] * data1[lag_ptr];
- lag_ptr++;
+
+ if(j==lag){
+ double sum = 1.0;
+ for(i=0; i<len; i+=2){
+ sum += data1[i ] * data1[i-j ]
+ + data1[i+1] * data1[i-j+1];
}
- ptr++;
+ autoc[j] = sum;
}
-
- av_freep(&data1);
}
/**
int32_t *lpc_out, int *shift)
{
int i;
- double d, cmax;
+ double cmax, error;
int32_t qmax;
int sh;
/* find maximum coefficient value */
cmax = 0.0;
for(i=0; i<order; i++) {
- d = lpc_in[i];
- if(d < 0) d = -d;
- if(d > cmax)
- cmax = d;
+ cmax= FFMAX(cmax, fabs(lpc_in[i]));
}
/* if maximum value quantizes to zero, return all zeros */
if(cmax * (1 << MAX_LPC_SHIFT) < 1.0) {
*shift = 0;
- for(i=0; i<order; i++) {
- lpc_out[i] = 0;
- }
+ memset(lpc_out, 0, sizeof(int32_t) * order);
return;
}
}
/* output quantized coefficients and level shift */
+ error=0;
for(i=0; i<order; i++) {
- lpc_out[i] = (int32_t)(lpc_in[i] * (1 << sh));
+ error += lpc_in[i] * (1 << sh);
+ lpc_out[i] = av_clip(lrintf(error), -qmax, qmax);
+ error -= lpc_out[i];
}
*shift = sh;
}
/**
* Calculate LPC coefficients for multiple orders
*/
-static int lpc_calc_coefs(const int32_t *samples, int blocksize, int max_order,
+static int lpc_calc_coefs(FlacEncodeContext *s,
+ const int32_t *samples, int blocksize, int max_order,
int precision, int32_t coefs[][MAX_LPC_ORDER],
- int *shift)
+ int *shift, int use_lpc, int omethod)
{
double autoc[MAX_LPC_ORDER+1];
double ref[MAX_LPC_ORDER];
double lpc[MAX_LPC_ORDER][MAX_LPC_ORDER];
- int i;
+ int i, j, pass;
int opt_order;
assert(max_order >= MIN_LPC_ORDER && max_order <= MAX_LPC_ORDER);
- compute_autocorr(samples, blocksize, max_order+1, autoc);
+ if(use_lpc == 1){
+ s->dsp.flac_compute_autocorr(samples, blocksize, max_order, autoc);
- compute_lpc_coefs(autoc, max_order, lpc, ref);
+ compute_lpc_coefs(autoc, max_order, lpc, ref);
+ }else{
+ LLSModel m[2];
+ double var[MAX_LPC_ORDER+1], weight;
+
+ for(pass=0; pass<use_lpc-1; pass++){
+ av_init_lls(&m[pass&1], max_order);
+
+ weight=0;
+ for(i=max_order; i<blocksize; i++){
+ for(j=0; j<=max_order; j++)
+ var[j]= samples[i-j];
+
+ if(pass){
+ double eval, inv, rinv;
+ eval= av_evaluate_lls(&m[(pass-1)&1], var+1, max_order-1);
+ eval= (512>>pass) + fabs(eval - var[0]);
+ inv = 1/eval;
+ rinv = sqrt(inv);
+ for(j=0; j<=max_order; j++)
+ var[j] *= rinv;
+ weight += inv;
+ }else
+ weight++;
+
+ av_update_lls(&m[pass&1], var, 1.0);
+ }
+ av_solve_lls(&m[pass&1], 0.001, 0);
+ }
- opt_order = estimate_best_order(ref, max_order);
+ for(i=0; i<max_order; i++){
+ for(j=0; j<max_order; j++)
+ lpc[i][j]= m[(pass-1)&1].coeff[i][j];
+ ref[i]= sqrt(m[(pass-1)&1].variance[i] / weight) * (blocksize - max_order) / 4000;
+ }
+ for(i=max_order-1; i>0; i--)
+ ref[i] = ref[i-1] - ref[i];
+ }
+ opt_order = max_order;
- i = opt_order-1;
- quantize_lpc_coefs(lpc[i], i+1, precision, coefs[i], &shift[i]);
+ if(omethod == ORDER_METHOD_EST) {
+ opt_order = estimate_best_order(ref, max_order);
+ i = opt_order-1;
+ quantize_lpc_coefs(lpc[i], i+1, precision, coefs[i], &shift[i]);
+ } else {
+ for(i=0; i<max_order; i++) {
+ quantize_lpc_coefs(lpc[i], i+1, precision, coefs[i], &shift[i]);
+ }
+ }
return opt_order;
}
for(i=order; i<n; i++)
res[i]= smp[i] - smp[i-1];
}else if(order==2){
- for(i=order; i<n; i++)
- res[i]= smp[i] - 2*smp[i-1] + smp[i-2];
+ int a = smp[order-1] - smp[order-2];
+ for(i=order; i<n; i+=2) {
+ int b = smp[i] - smp[i-1];
+ res[i]= b - a;
+ a = smp[i+1] - smp[i];
+ res[i+1]= a - b;
+ }
}else if(order==3){
- for(i=order; i<n; i++)
- res[i]= smp[i] - 3*smp[i-1] + 3*smp[i-2] - smp[i-3];
+ int a = smp[order-1] - smp[order-2];
+ int c = smp[order-1] - 2*smp[order-2] + smp[order-3];
+ for(i=order; i<n; i+=2) {
+ int b = smp[i] - smp[i-1];
+ int d = b - a;
+ res[i]= d - c;
+ a = smp[i+1] - smp[i];
+ c = a - b;
+ res[i+1]= c - d;
+ }
}else{
- for(i=order; i<n; i++)
- res[i]= smp[i] - 4*smp[i-1] + 6*smp[i-2] - 4*smp[i-3] + smp[i-4];
+ int a = smp[order-1] - smp[order-2];
+ int c = smp[order-1] - 2*smp[order-2] + smp[order-3];
+ int e = smp[order-1] - 3*smp[order-2] + 3*smp[order-3] - smp[order-4];
+ for(i=order; i<n; i+=2) {
+ int b = smp[i] - smp[i-1];
+ int d = b - a;
+ int f = d - c;
+ res[i]= f - e;
+ a = smp[i+1] - smp[i];
+ c = a - b;
+ e = c - d;
+ res[i+1]= e - f;
+ }
+ }
+}
+
+#define LPC1(x) {\
+ int c = coefs[(x)-1];\
+ p0 += c*s;\
+ s = smp[i-(x)+1];\
+ p1 += c*s;\
+}
+
+static av_always_inline void encode_residual_lpc_unrolled(
+ int32_t *res, const int32_t *smp, int n,
+ int order, const int32_t *coefs, int shift, int big)
+{
+ int i;
+ for(i=order; i<n; i+=2) {
+ int s = smp[i-order];
+ int p0 = 0, p1 = 0;
+ if(big) {
+ switch(order) {
+ case 32: LPC1(32)
+ case 31: LPC1(31)
+ case 30: LPC1(30)
+ case 29: LPC1(29)
+ case 28: LPC1(28)
+ case 27: LPC1(27)
+ case 26: LPC1(26)
+ case 25: LPC1(25)
+ case 24: LPC1(24)
+ case 23: LPC1(23)
+ case 22: LPC1(22)
+ case 21: LPC1(21)
+ case 20: LPC1(20)
+ case 19: LPC1(19)
+ case 18: LPC1(18)
+ case 17: LPC1(17)
+ case 16: LPC1(16)
+ case 15: LPC1(15)
+ case 14: LPC1(14)
+ case 13: LPC1(13)
+ case 12: LPC1(12)
+ case 11: LPC1(11)
+ case 10: LPC1(10)
+ case 9: LPC1( 9)
+ LPC1( 8)
+ LPC1( 7)
+ LPC1( 6)
+ LPC1( 5)
+ LPC1( 4)
+ LPC1( 3)
+ LPC1( 2)
+ LPC1( 1)
+ }
+ } else {
+ switch(order) {
+ case 8: LPC1( 8)
+ case 7: LPC1( 7)
+ case 6: LPC1( 6)
+ case 5: LPC1( 5)
+ case 4: LPC1( 4)
+ case 3: LPC1( 3)
+ case 2: LPC1( 2)
+ case 1: LPC1( 1)
+ }
+ }
+ res[i ] = smp[i ] - (p0 >> shift);
+ res[i+1] = smp[i+1] - (p1 >> shift);
}
}
static void encode_residual_lpc(int32_t *res, const int32_t *smp, int n,
int order, const int32_t *coefs, int shift)
{
- int i, j;
- int32_t pred;
-
+ int i;
for(i=0; i<order; i++) {
res[i] = smp[i];
}
- for(i=order; i<n; i++) {
- pred = 0;
+#ifdef CONFIG_SMALL
+ for(i=order; i<n; i+=2) {
+ int j;
+ int s = smp[i];
+ int p0 = 0, p1 = 0;
for(j=0; j<order; j++) {
- pred += coefs[j] * smp[i-j-1];
+ int c = coefs[j];
+ p1 += c*s;
+ s = smp[i-j-1];
+ p0 += c*s;
}
- res[i] = smp[i] - (pred >> shift);
- }
-}
-
-static int get_max_p_order(int max_porder, int n, int order)
-{
- int porder, max_parts;
-
- porder = max_porder;
- while(porder > 0) {
- max_parts = (1 << porder);
- if(!(n % max_parts) && (n > max_parts*order)) {
- break;
- }
- porder--;
- }
- return porder;
+ res[i ] = smp[i ] - (p0 >> shift);
+ res[i+1] = smp[i+1] - (p1 >> shift);
+ }
+#else
+ switch(order) {
+ case 1: encode_residual_lpc_unrolled(res, smp, n, 1, coefs, shift, 0); break;
+ case 2: encode_residual_lpc_unrolled(res, smp, n, 2, coefs, shift, 0); break;
+ case 3: encode_residual_lpc_unrolled(res, smp, n, 3, coefs, shift, 0); break;
+ case 4: encode_residual_lpc_unrolled(res, smp, n, 4, coefs, shift, 0); break;
+ case 5: encode_residual_lpc_unrolled(res, smp, n, 5, coefs, shift, 0); break;
+ case 6: encode_residual_lpc_unrolled(res, smp, n, 6, coefs, shift, 0); break;
+ case 7: encode_residual_lpc_unrolled(res, smp, n, 7, coefs, shift, 0); break;
+ case 8: encode_residual_lpc_unrolled(res, smp, n, 8, coefs, shift, 0); break;
+ default: encode_residual_lpc_unrolled(res, smp, n, order, coefs, shift, 1); break;
+ }
+#endif
}
static int encode_residual(FlacEncodeContext *ctx, int ch)
{
int i, n;
- int min_order, max_order, opt_order, precision;
- int porder, min_porder, max_porder;
+ int min_order, max_order, opt_order, precision, omethod;
+ int min_porder, max_porder;
FlacFrame *frame;
FlacSubframe *sub;
int32_t coefs[MAX_LPC_ORDER][MAX_LPC_ORDER];
min_porder = ctx->options.min_partition_order;
max_porder = ctx->options.max_partition_order;
precision = ctx->options.lpc_coeff_precision;
+ omethod = ctx->options.prediction_order_method;
/* FIXED */
if(!ctx->options.use_lpc || max_order == 0 || (n <= max_order)) {
bits[0] = UINT32_MAX;
for(i=min_order; i<=max_order; i++) {
encode_residual_fixed(res, smp, n, i);
- porder = get_max_p_order(max_porder, n, i);
- bits[i] = calc_rice_params_fixed(&sub->rc, min_porder, porder, res,
+ bits[i] = calc_rice_params_fixed(&sub->rc, min_porder, max_porder, res,
n, i, sub->obits);
if(bits[i] < bits[opt_order]) {
opt_order = i;
sub->type_code = sub->type | sub->order;
if(sub->order != max_order) {
encode_residual_fixed(res, smp, n, sub->order);
- porder = get_max_p_order(max_porder, n, sub->order);
- return calc_rice_params_fixed(&sub->rc, min_porder, porder, res, n,
+ return calc_rice_params_fixed(&sub->rc, min_porder, max_porder, res, n,
sub->order, sub->obits);
}
return bits[sub->order];
}
/* LPC */
- sub->order = lpc_calc_coefs(smp, n, max_order, precision, coefs, shift);
+ opt_order = lpc_calc_coefs(ctx, smp, n, max_order, precision, coefs, shift, ctx->options.use_lpc, omethod);
+
+ if(omethod == ORDER_METHOD_2LEVEL ||
+ omethod == ORDER_METHOD_4LEVEL ||
+ omethod == ORDER_METHOD_8LEVEL) {
+ int levels = 1 << omethod;
+ uint32_t bits[levels];
+ int order;
+ int opt_index = levels-1;
+ opt_order = max_order-1;
+ bits[opt_index] = UINT32_MAX;
+ for(i=levels-1; i>=0; i--) {
+ order = min_order + (((max_order-min_order+1) * (i+1)) / levels)-1;
+ if(order < 0) order = 0;
+ encode_residual_lpc(res, smp, n, order+1, coefs[order], shift[order]);
+ bits[i] = calc_rice_params_lpc(&sub->rc, min_porder, max_porder,
+ res, n, order+1, sub->obits, precision);
+ if(bits[i] < bits[opt_index]) {
+ opt_index = i;
+ opt_order = order;
+ }
+ }
+ opt_order++;
+ } else if(omethod == ORDER_METHOD_SEARCH) {
+ // brute-force optimal order search
+ uint32_t bits[MAX_LPC_ORDER];
+ opt_order = 0;
+ bits[0] = UINT32_MAX;
+ for(i=min_order-1; i<max_order; i++) {
+ encode_residual_lpc(res, smp, n, i+1, coefs[i], shift[i]);
+ bits[i] = calc_rice_params_lpc(&sub->rc, min_porder, max_porder,
+ res, n, i+1, sub->obits, precision);
+ if(bits[i] < bits[opt_order]) {
+ opt_order = i;
+ }
+ }
+ opt_order++;
+ } else if(omethod == ORDER_METHOD_LOG) {
+ uint32_t bits[MAX_LPC_ORDER];
+ int step;
+
+ opt_order= min_order - 1 + (max_order-min_order)/3;
+ memset(bits, -1, sizeof(bits));
+
+ for(step=16 ;step; step>>=1){
+ int last= opt_order;
+ for(i=last-step; i<=last+step; i+= step){
+ if(i<min_order-1 || i>=max_order || bits[i] < UINT32_MAX)
+ continue;
+ encode_residual_lpc(res, smp, n, i+1, coefs[i], shift[i]);
+ bits[i] = calc_rice_params_lpc(&sub->rc, min_porder, max_porder,
+ res, n, i+1, sub->obits, precision);
+ if(bits[i] < bits[opt_order])
+ opt_order= i;
+ }
+ }
+ opt_order++;
+ }
+
+ sub->order = opt_order;
sub->type = FLAC_SUBFRAME_LPC;
sub->type_code = sub->type | (sub->order-1);
sub->shift = shift[sub->order-1];
for(i=0; i<sub->order; i++) {
sub->coefs[i] = coefs[sub->order-1][i];
}
- porder = get_max_p_order(max_porder, n, sub->order);
encode_residual_lpc(res, smp, n, sub->order, sub->coefs, sub->shift);
- return calc_rice_params_lpc(&sub->rc, 0, porder, res, n, sub->order,
+ return calc_rice_params_lpc(&sub->rc, min_porder, max_porder, res, n, sub->order,
sub->obits, precision);
}
for(i=2; i<n; i++) {
lt = left_ch[i] - 2*left_ch[i-1] + left_ch[i-2];
rt = right_ch[i] - 2*right_ch[i-1] + right_ch[i-2];
- sum[2] += ABS((lt + rt) >> 1);
- sum[3] += ABS(lt - rt);
- sum[0] += ABS(lt);
- sum[1] += ABS(rt);
+ sum[2] += FFABS((lt + rt) >> 1);
+ sum[3] += FFABS(lt - rt);
+ sum[0] += FFABS(lt);
+ sum[1] += FFABS(rt);
}
/* estimate bit counts */
for(i=0; i<4; i++) {
static void write_utf8(PutBitContext *pb, uint32_t val)
{
- int bytes, shift;
-
- if(val < 0x80){
- put_bits(pb, 8, val);
- return;
- }
-
- bytes= (av_log2(val)+4) / 5;
- shift = (bytes - 1) * 6;
- put_bits(pb, 8, (256 - (256>>bytes)) | (val >> shift));
- while(shift >= 6){
- shift -= 6;
- put_bits(pb, 8, 0x80 | ((val >> shift) & 0x3F));
- }
+ uint8_t tmp;
+ PUT_UTF8(val, tmp, put_bits(pb, 8, tmp);)
}
static void output_frame_header(FlacEncodeContext *s)