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authorSean Bartell <wingedtachikoma@gmail.com>2011-06-25 21:32:25 -0400
committerNils Wallménius <nils@rockbox.org>2012-04-25 22:13:20 +0200
commitf40bfc9267b13b54e6379dfe7539447662879d24 (patch)
tree9b20069d5e62809ff434061ad730096836f916f2 /lib/rbcodec/codecs/libffmpegFLAC/decoder.c
parenta0009907de7a0107d49040d8a180f140e2eff299 (diff)
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Add codecs to librbcodec.
Change-Id: Id7f4717d51ed02d67cb9f9cb3c0ada4a81843f97 Reviewed-on: http://gerrit.rockbox.org/137 Reviewed-by: Nils Wallménius <nils@rockbox.org> Tested-by: Nils Wallménius <nils@rockbox.org>
Diffstat (limited to 'lib/rbcodec/codecs/libffmpegFLAC/decoder.c')
-rw-r--r--lib/rbcodec/codecs/libffmpegFLAC/decoder.c627
1 files changed, 627 insertions, 0 deletions
diff --git a/lib/rbcodec/codecs/libffmpegFLAC/decoder.c b/lib/rbcodec/codecs/libffmpegFLAC/decoder.c
new file mode 100644
index 0000000..2e92c4b
--- /dev/null
+++ b/lib/rbcodec/codecs/libffmpegFLAC/decoder.c
@@ -0,0 +1,627 @@
+/*
+ * FLAC (Free Lossless Audio Codec) decoder
+ * Copyright (c) 2003 Alex Beregszaszi
+ *
+ * This library 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.
+ *
+ * This library 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
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+/**
+ * @file flac.c
+ * FLAC (Free Lossless Audio Codec) decoder
+ * @author Alex Beregszaszi
+ *
+ * For more information on the FLAC format, visit:
+ * http://flac.sourceforge.net/
+ *
+ * This decoder can be used in 1 of 2 ways: Either raw FLAC data can be fed
+ * through, starting from the initial 'fLaC' signature; or by passing the
+ * 34-byte streaminfo structure through avctx->extradata[_size] followed
+ * by data starting with the 0xFFF8 marker.
+ */
+
+#include <inttypes.h>
+#include <stdbool.h>
+#ifndef BUILD_STANDALONE
+#include "codeclib.h"
+#endif
+
+#include "bitstream.h"
+#include "golomb.h"
+
+#include "decoder.h"
+
+#if defined(CPU_COLDFIRE)
+#include "coldfire.h"
+#elif defined(CPU_ARM)
+#include "arm.h"
+#endif
+
+static const int sample_rate_table[] ICONST_ATTR =
+{ 0, 88200, 176400, 192000,
+ 8000, 16000, 22050, 24000, 32000, 44100, 48000, 96000,
+ 0, 0, 0, 0 };
+
+static const int sample_size_table[] ICONST_ATTR =
+{ 0, 8, 12, 0, 16, 20, 24, 0 };
+
+static const int blocksize_table[] ICONST_ATTR = {
+ 0, 192, 576<<0, 576<<1, 576<<2, 576<<3, 0, 0,
+256<<0, 256<<1, 256<<2, 256<<3, 256<<4, 256<<5, 256<<6, 256<<7
+};
+
+static const uint8_t table_crc8[256] ICONST_ATTR = {
+ 0x00, 0x07, 0x0e, 0x09, 0x1c, 0x1b, 0x12, 0x15,
+ 0x38, 0x3f, 0x36, 0x31, 0x24, 0x23, 0x2a, 0x2d,
+ 0x70, 0x77, 0x7e, 0x79, 0x6c, 0x6b, 0x62, 0x65,
+ 0x48, 0x4f, 0x46, 0x41, 0x54, 0x53, 0x5a, 0x5d,
+ 0xe0, 0xe7, 0xee, 0xe9, 0xfc, 0xfb, 0xf2, 0xf5,
+ 0xd8, 0xdf, 0xd6, 0xd1, 0xc4, 0xc3, 0xca, 0xcd,
+ 0x90, 0x97, 0x9e, 0x99, 0x8c, 0x8b, 0x82, 0x85,
+ 0xa8, 0xaf, 0xa6, 0xa1, 0xb4, 0xb3, 0xba, 0xbd,
+ 0xc7, 0xc0, 0xc9, 0xce, 0xdb, 0xdc, 0xd5, 0xd2,
+ 0xff, 0xf8, 0xf1, 0xf6, 0xe3, 0xe4, 0xed, 0xea,
+ 0xb7, 0xb0, 0xb9, 0xbe, 0xab, 0xac, 0xa5, 0xa2,
+ 0x8f, 0x88, 0x81, 0x86, 0x93, 0x94, 0x9d, 0x9a,
+ 0x27, 0x20, 0x29, 0x2e, 0x3b, 0x3c, 0x35, 0x32,
+ 0x1f, 0x18, 0x11, 0x16, 0x03, 0x04, 0x0d, 0x0a,
+ 0x57, 0x50, 0x59, 0x5e, 0x4b, 0x4c, 0x45, 0x42,
+ 0x6f, 0x68, 0x61, 0x66, 0x73, 0x74, 0x7d, 0x7a,
+ 0x89, 0x8e, 0x87, 0x80, 0x95, 0x92, 0x9b, 0x9c,
+ 0xb1, 0xb6, 0xbf, 0xb8, 0xad, 0xaa, 0xa3, 0xa4,
+ 0xf9, 0xfe, 0xf7, 0xf0, 0xe5, 0xe2, 0xeb, 0xec,
+ 0xc1, 0xc6, 0xcf, 0xc8, 0xdd, 0xda, 0xd3, 0xd4,
+ 0x69, 0x6e, 0x67, 0x60, 0x75, 0x72, 0x7b, 0x7c,
+ 0x51, 0x56, 0x5f, 0x58, 0x4d, 0x4a, 0x43, 0x44,
+ 0x19, 0x1e, 0x17, 0x10, 0x05, 0x02, 0x0b, 0x0c,
+ 0x21, 0x26, 0x2f, 0x28, 0x3d, 0x3a, 0x33, 0x34,
+ 0x4e, 0x49, 0x40, 0x47, 0x52, 0x55, 0x5c, 0x5b,
+ 0x76, 0x71, 0x78, 0x7f, 0x6a, 0x6d, 0x64, 0x63,
+ 0x3e, 0x39, 0x30, 0x37, 0x22, 0x25, 0x2c, 0x2b,
+ 0x06, 0x01, 0x08, 0x0f, 0x1a, 0x1d, 0x14, 0x13,
+ 0xae, 0xa9, 0xa0, 0xa7, 0xb2, 0xb5, 0xbc, 0xbb,
+ 0x96, 0x91, 0x98, 0x9f, 0x8a, 0x8d, 0x84, 0x83,
+ 0xde, 0xd9, 0xd0, 0xd7, 0xc2, 0xc5, 0xcc, 0xcb,
+ 0xe6, 0xe1, 0xe8, 0xef, 0xfa, 0xfd, 0xf4, 0xf3
+};
+
+static int64_t get_utf8(GetBitContext *gb) ICODE_ATTR_FLAC;
+static int64_t get_utf8(GetBitContext *gb)
+{
+ uint64_t val;
+ int ones=0, bytes;
+
+ while(get_bits1(gb))
+ ones++;
+
+ if (ones==0) bytes=0;
+ else if(ones==1) return -1;
+ else bytes= ones - 1;
+
+ val= get_bits(gb, 7-ones);
+ while(bytes--){
+ const int tmp = get_bits(gb, 8);
+
+ if((tmp>>6) != 2)
+ return -2;
+ val<<=6;
+ val|= tmp&0x3F;
+ }
+ return val;
+}
+
+static int get_crc8(const uint8_t *buf, int count) ICODE_ATTR_FLAC;
+static int get_crc8(const uint8_t *buf, int count)
+{
+ int crc=0;
+ int i;
+
+ for(i=0; i<count; i++){
+ crc = table_crc8[crc ^ buf[i]];
+ }
+
+ return crc;
+}
+
+static int decode_residuals(FLACContext *s, int32_t* decoded, int pred_order) ICODE_ATTR_FLAC;
+static int decode_residuals(FLACContext *s, int32_t* decoded, int pred_order)
+{
+ int i, tmp, partition, method_type, rice_order;
+ int sample = 0, samples;
+
+ method_type = get_bits(&s->gb, 2);
+ if (method_type > 1){
+ //fprintf(stderr,"illegal residual coding method %d\n", method_type);
+ return -3;
+ }
+
+ rice_order = get_bits(&s->gb, 4);
+
+ samples= s->blocksize >> rice_order;
+
+ sample=
+ i= pred_order;
+ for (partition = 0; partition < (1 << rice_order); partition++)
+ {
+ tmp = get_bits(&s->gb, method_type == 0 ? 4 : 5);
+ if (tmp == (method_type == 0 ? 15 : 31))
+ {
+ //fprintf(stderr,"fixed len partition\n");
+ tmp = get_bits(&s->gb, 5);
+ for (; i < samples; i++, sample++)
+ decoded[sample] = get_sbits(&s->gb, tmp);
+ }
+ else
+ {
+ for (; i < samples; i++, sample++){
+ decoded[sample] = get_sr_golomb_flac(&s->gb, tmp, INT_MAX, 0);
+ }
+ }
+ i= 0;
+ }
+
+ return 0;
+}
+
+static int decode_subframe_fixed(FLACContext *s, int32_t* decoded, int pred_order) ICODE_ATTR_FLAC;
+static int decode_subframe_fixed(FLACContext *s, int32_t* decoded, int pred_order)
+{
+ const int blocksize = s->blocksize;
+ int a, b, c, d, i;
+
+ /* warm up samples */
+ for (i = 0; i < pred_order; i++)
+ {
+ decoded[i] = get_sbits(&s->gb, s->curr_bps);
+ }
+
+ if (decode_residuals(s, decoded, pred_order) < 0)
+ return -4;
+
+ a = decoded[pred_order-1];
+ b = a - decoded[pred_order-2];
+ c = b - decoded[pred_order-2] + decoded[pred_order-3];
+ d = c - decoded[pred_order-2] + 2*decoded[pred_order-3] - decoded[pred_order-4];
+
+ switch(pred_order)
+ {
+ case 0:
+ break;
+ case 1:
+ for (i = pred_order; i < blocksize; i++)
+ decoded[i] = a += decoded[i];
+ break;
+ case 2:
+ for (i = pred_order; i < blocksize; i++)
+ decoded[i] = a += b += decoded[i];
+ break;
+ case 3:
+ for (i = pred_order; i < blocksize; i++)
+ decoded[i] = a += b += c += decoded[i];
+ break;
+ case 4:
+ for (i = pred_order; i < blocksize; i++)
+ decoded[i] = a += b += c += d += decoded[i];
+ break;
+ default:
+ return -5;
+ }
+
+ return 0;
+}
+
+static int decode_subframe_lpc(FLACContext *s, int32_t* decoded, int pred_order) ICODE_ATTR_FLAC;
+static int decode_subframe_lpc(FLACContext *s, int32_t* decoded, int pred_order)
+{
+ int sum, i, j;
+ int64_t wsum;
+ int coeff_prec, qlevel;
+ int coeffs[pred_order];
+
+ /* warm up samples */
+ for (i = 0; i < pred_order; i++)
+ {
+ decoded[i] = get_sbits(&s->gb, s->curr_bps);
+ }
+
+ coeff_prec = get_bits(&s->gb, 4) + 1;
+ if (coeff_prec == 16)
+ {
+ //fprintf(stderr,"invalid coeff precision\n");
+ return -6;
+ }
+ qlevel = get_sbits(&s->gb, 5);
+ if (qlevel < 0)
+ {
+ //fprintf(stderr,"qlevel %d not supported, maybe buggy stream\n", qlevel);
+ return -7;
+ }
+
+ for (i = 0; i < pred_order; i++)
+ {
+ coeffs[i] = get_sbits(&s->gb, coeff_prec);
+ }
+
+ if (decode_residuals(s, decoded, pred_order) < 0)
+ return -8;
+
+ if ((s->bps + coeff_prec + av_log2(pred_order)) <= 32) {
+ #if defined(CPU_COLDFIRE)
+ (void)sum;
+ lpc_decode_emac(s->blocksize - pred_order, qlevel, pred_order,
+ decoded + pred_order, coeffs);
+ #elif defined(CPU_ARM)
+ (void)sum;
+ lpc_decode_arm(s->blocksize - pred_order, qlevel, pred_order,
+ decoded + pred_order, coeffs);
+ #else
+ for (i = pred_order; i < s->blocksize; i++)
+ {
+ sum = 0;
+ for (j = 0; j < pred_order; j++)
+ sum += coeffs[j] * decoded[i-j-1];
+ decoded[i] += sum >> qlevel;
+ }
+ #endif
+ } else {
+ #if defined(CPU_COLDFIRE)
+ (void)wsum;
+ (void)j;
+ lpc_decode_emac_wide(s->blocksize - pred_order, qlevel, pred_order,
+ decoded + pred_order, coeffs);
+ #else
+ for (i = pred_order; i < s->blocksize; i++)
+ {
+ wsum = 0;
+ for (j = 0; j < pred_order; j++)
+ wsum += (int64_t)coeffs[j] * (int64_t)decoded[i-j-1];
+ decoded[i] += wsum >> qlevel;
+ }
+ #endif
+ }
+
+ return 0;
+}
+
+static inline int decode_subframe(FLACContext *s, int channel, int32_t* decoded)
+{
+ int type, wasted = 0;
+ int i, tmp;
+
+ s->curr_bps = s->bps;
+ if(channel == 0){
+ if(s->decorrelation == RIGHT_SIDE)
+ s->curr_bps++;
+ }else{
+ if(s->decorrelation == LEFT_SIDE || s->decorrelation == MID_SIDE)
+ s->curr_bps++;
+ }
+
+ if (get_bits1(&s->gb))
+ {
+ //fprintf(stderr,"invalid subframe padding\n");
+ return -9;
+ }
+ type = get_bits(&s->gb, 6);
+// wasted = get_bits1(&s->gb);
+
+// if (wasted)
+// {
+// while (!get_bits1(&s->gb))
+// wasted++;
+// if (wasted)
+// wasted++;
+// s->curr_bps -= wasted;
+// }
+#if 0
+ wasted= 16 - av_log2(show_bits(&s->gb, 17));
+ skip_bits(&s->gb, wasted+1);
+ s->curr_bps -= wasted;
+#else
+ if (get_bits1(&s->gb))
+ {
+ wasted = 1;
+ while (!get_bits1(&s->gb))
+ wasted++;
+ s->curr_bps -= wasted;
+ //fprintf(stderr,"%d wasted bits\n", wasted);
+ }
+#endif
+//FIXME use av_log2 for types
+ if (type == 0)
+ {
+ //fprintf(stderr,"coding type: constant\n");
+ tmp = get_sbits(&s->gb, s->curr_bps);
+ for (i = 0; i < s->blocksize; i++)
+ decoded[i] = tmp;
+ }
+ else if (type == 1)
+ {
+ //fprintf(stderr,"coding type: verbatim\n");
+ for (i = 0; i < s->blocksize; i++)
+ decoded[i] = get_sbits(&s->gb, s->curr_bps);
+ }
+ else if ((type >= 8) && (type <= 12))
+ {
+ //fprintf(stderr,"coding type: fixed\n");
+ if (decode_subframe_fixed(s, decoded, type & ~0x8) < 0)
+ return -10;
+ }
+ else if (type >= 32)
+ {
+ //fprintf(stderr,"coding type: lpc\n");
+ if (decode_subframe_lpc(s, decoded, (type & ~0x20)+1) < 0)
+ return -11;
+ }
+ else
+ {
+ //fprintf(stderr,"Unknown coding type: %d\n",type);
+ return -12;
+ }
+
+ if (wasted)
+ {
+ int i;
+ for (i = 0; i < s->blocksize; i++)
+ decoded[i] <<= wasted;
+ }
+
+ return 0;
+}
+
+static int decode_frame(FLACContext *s,
+ void (*yield)(void)) ICODE_ATTR_FLAC;
+static int decode_frame(FLACContext *s,
+ void (*yield)(void))
+{
+ int blocksize_code, sample_rate_code, sample_size_code, assignment, crc8;
+ int decorrelation, bps, blocksize, samplerate;
+ int res, ch;
+
+ blocksize_code = get_bits(&s->gb, 4);
+
+ sample_rate_code = get_bits(&s->gb, 4);
+
+ assignment = get_bits(&s->gb, 4); /* channel assignment */
+ if (assignment < 8 && s->channels == assignment+1)
+ decorrelation = INDEPENDENT;
+ else if (assignment >=8 && assignment < 11 && s->channels == 2)
+ decorrelation = LEFT_SIDE + assignment - 8;
+ else
+ {
+ return -13;
+ }
+
+ sample_size_code = get_bits(&s->gb, 3);
+ if(sample_size_code == 0)
+ bps= s->bps;
+ else if((sample_size_code != 3) && (sample_size_code != 7))
+ bps = sample_size_table[sample_size_code];
+ else
+ {
+ return -14;
+ }
+
+ if (get_bits1(&s->gb))
+ {
+ return -15;
+ }
+
+ /* Get the samplenumber of the first sample in this block */
+ s->samplenumber=get_utf8(&s->gb);
+
+ /* samplenumber actually contains the frame number for streams
+ with a constant block size - so we multiply by blocksize to
+ get the actual sample number */
+ if (s->min_blocksize == s->max_blocksize) {
+ s->samplenumber*=s->min_blocksize;
+ }
+
+#if 0
+ if (/*((blocksize_code == 6) || (blocksize_code == 7)) &&*/
+ (s->min_blocksize != s->max_blocksize)){
+ }else{
+ }
+#endif
+
+ if (blocksize_code == 0)
+ blocksize = s->min_blocksize;
+ else if (blocksize_code == 6)
+ blocksize = get_bits(&s->gb, 8)+1;
+ else if (blocksize_code == 7)
+ blocksize = get_bits(&s->gb, 16)+1;
+ else
+ blocksize = blocksize_table[blocksize_code];
+
+ if(blocksize > s->max_blocksize){
+ return -16;
+ }
+
+ if (sample_rate_code == 0){
+ samplerate= s->samplerate;
+ }else if ((sample_rate_code < 12))
+ samplerate = sample_rate_table[sample_rate_code];
+ else if (sample_rate_code == 12)
+ samplerate = get_bits(&s->gb, 8) * 1000;
+ else if (sample_rate_code == 13)
+ samplerate = get_bits(&s->gb, 16);
+ else if (sample_rate_code == 14)
+ samplerate = get_bits(&s->gb, 16) * 10;
+ else{
+ return -17;
+ }
+
+ skip_bits(&s->gb, 8);
+ crc8= get_crc8(s->gb.buffer, get_bits_count(&s->gb)/8);
+ if(crc8){
+ return -18;
+ }
+
+ s->blocksize = blocksize;
+ s->samplerate = samplerate;
+ s->bps = bps;
+ s->decorrelation= decorrelation;
+
+ for (ch=0; ch<s->channels; ++ch) {
+ yield();
+ if ((res=decode_subframe(s, ch, s->decoded[ch])) < 0)
+ return res-100;
+ }
+
+ yield();
+ align_get_bits(&s->gb);
+
+ /* frame footer */
+ skip_bits(&s->gb, 16); /* data crc */
+
+ return 0;
+}
+
+static int flac_downmix(FLACContext *s) ICODE_ATTR_FLAC;
+static int flac_downmix(FLACContext *s)
+{
+ int32_t *FL, *FR, *FC, *SB, *RL, *RR;
+ int32_t *outL = s->decoded[0];
+ int32_t *outR = s->decoded[1];
+ int i, scale=FLAC_OUTPUT_DEPTH-s->bps;
+
+ switch(s->channels)
+ {
+ case 3: /* 3.0 channel order: FL FR FC */
+ FL = s->decoded[0];
+ FR = s->decoded[1];
+ FC = s->decoded[2];
+ /* LF = 0.66 LF + 0.33 FC
+ LR = 0.66 LR + 0.33 FC */
+ for (i=0; i<s->blocksize; ++i) {
+ int32_t a = *(FL)*2 + *(FC);
+ int32_t b = *(FR)*2 + *(FC);
+ *outL++ = ((a + (a<<2))>>4) << scale; /* 1/3 ~= 5>>4 */
+ *outR++ = ((b + (b<<2))>>4) << scale; /* 1/3 ~= 5>>4 */
+ FL++; FR++; FC++;
+ }
+ break;
+ case 4: /* 4.0 channel order: FL FR RL RR */
+ FL = s->decoded[0];
+ FR = s->decoded[1];
+ RL = s->decoded[2];
+ RR = s->decoded[3];
+ /* LF = 0.50 LF + 0.50 RL + 0.00 RR
+ LR = 0.50 LR + 0.00 RL + 0.50 RR */
+ for (i=0; i<s->blocksize; ++i) {
+ int32_t a = *(FL) + *(RL);
+ int32_t b = *(FR) + *(RR);
+ *outL++ = (a>>1) << scale;
+ *outR++ = (b>>1) << scale;
+ FL++; FR++; RL++; RR++;
+ }
+ break;
+ case 5: /* 5.0 channel order: FL FR FC RL RR */
+ FL = s->decoded[0];
+ FR = s->decoded[1];
+ FC = s->decoded[2];
+ RL = s->decoded[3];
+ RR = s->decoded[4];
+ /* LF = 0.40 LF + 0.20 FC + 0.40 RL + 0.00 RR
+ LR = 0.40 LR + 0.20 FC + 0.00 RL + 0.40 RR */
+ for (i=0; i<s->blocksize; ++i) {
+ int32_t a = *(FL)*2 + *(FC) + *(RL)*2;
+ int32_t b = *(FR)*2 + *(FC) + *(RR)*2;
+ *outL++ = ((a + (a<<1))>>4) << scale; /* 3>>4 ~= 1/5 */
+ *outR++ = ((b + (b<<1))>>4) << scale; /* 3>>4 ~= 1/5 */
+ FL++; FR++; FC++; RL++; RR++;
+ }
+ break;
+ case 6: /* 5.1 channel order: FL FR FC SUB RL RR */
+ FL = s->decoded[0];
+ FR = s->decoded[1];
+ FC = s->decoded[2];
+ SB = s->decoded[3];
+ RL = s->decoded[4];
+ RR = s->decoded[5];
+ /* LF = 0.33 LF + 0.16 SUB + 0.16 FC + 0.33 RL + 0.00 RR
+ LR = 0.33 LR + 0.16 SUB + 0.16 FC + 0.00 RL + 0.33 RR */
+ for (i=0; i<s->blocksize; ++i) {
+ int32_t a = *(FL)*2 + *(SB) + *(FC) + *(RL)*2;
+ int32_t b = *(FR)*2 + *(SB) + *(FC) + *(RR)*2;
+ *outL++ = ((a + (a<<2))>>5) << scale; /* 5>>5 ~= 1/6 */
+ *outR++ = ((b + (b<<2))>>5) << scale; /* 5>>5 ~= 1/6 */
+ FL++; FR++; SB++; FC++; RL++; RR++;
+ }
+ break;
+ default: /* 1.0 and 2.0 do not need downmix, other formats unknown. */
+ return -501;
+ break;
+ }
+ return 0;
+}
+
+int flac_decode_frame(FLACContext *s,
+ uint8_t *buf, int buf_size,
+ void (*yield)(void))
+{
+ int tmp;
+ int i;
+ int framesize;
+ int scale;
+
+ init_get_bits(&s->gb, buf, buf_size*8);
+
+ tmp = get_bits(&s->gb, 16);
+ if ((tmp & 0xFFFE) != 0xFFF8){
+ return -41;
+ }
+
+ if ((framesize=decode_frame(s,yield)) < 0){
+ s->bitstream_size=0;
+ s->bitstream_index=0;
+ return framesize;
+ }
+
+ yield();
+
+#define DECORRELATE(left, right)\
+ for (i = 0; i < s->blocksize; i++) {\
+ int32_t a = s->decoded[0][i];\
+ int32_t b = s->decoded[1][i];\
+ s->decoded[0][i] = (left) << scale;\
+ s->decoded[1][i] = (right) << scale;\
+ }\
+
+ scale=FLAC_OUTPUT_DEPTH-s->bps;
+ switch(s->decorrelation)
+ {
+ case INDEPENDENT:
+ if (s->channels <= 2) {
+ DECORRELATE(a, b) /* Always decorrelate exactly the two supported channels. */
+ } else {
+ if ((tmp=flac_downmix(s)) != 0)
+ return tmp;
+ }
+ break;
+ case LEFT_SIDE:
+ DECORRELATE(a, a-b)
+ break;
+ case RIGHT_SIDE:
+ DECORRELATE(a+b, b)
+ break;
+ case MID_SIDE:
+ DECORRELATE( (a-=b>>1) + b, a)
+ break;
+ }
+
+ s->framesize = (get_bits_count(&s->gb)+7)>>3;
+
+ return 0;
+}