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rockbox/apps/codecs/libffmpegFLAC/decoder.c

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/*
* 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,
int32_t* decoded0,
int32_t* decoded1,
void (*yield)(void)) ICODE_ATTR_FLAC;
static int decode_frame(FLACContext *s,
int32_t* decoded0,
int32_t* decoded1,
void (*yield)(void))
{
int blocksize_code, sample_rate_code, sample_size_code, assignment, crc8;
int decorrelation, bps, blocksize, samplerate;
int res;
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;
yield();
/* subframes */
if ((res=decode_subframe(s, 0, decoded0)) < 0)
return res-100;
yield();
if (s->channels==2) {
if ((res=decode_subframe(s, 1, decoded1)) < 0)
return res-200;
}
yield();
align_get_bits(&s->gb);
/* frame footer */
skip_bits(&s->gb, 16); /* data crc */
return 0;
}
int flac_decode_frame(FLACContext *s,
int32_t* decoded0,
int32_t* decoded1,
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,decoded0,decoded1,yield)) < 0){
s->bitstream_size=0;
s->bitstream_index=0;
return framesize;
}
yield();
scale=FLAC_OUTPUT_DEPTH-s->bps;
switch(s->decorrelation)
{
case INDEPENDENT:
if (s->channels==1) {;
for (i = 0; i < s->blocksize; i++)
{
decoded0[i] = decoded0[i] << scale;
}
} else {
for (i = 0; i < s->blocksize; i++)
{
decoded0[i] = decoded0[i] << scale;
decoded1[i] = decoded1[i] << scale;
}
}
break;
case LEFT_SIDE:
//assert(s->channels == 2);
for (i = 0; i < s->blocksize; i++)
{
decoded1[i] = (decoded0[i] - decoded1[i]) << scale;
decoded0[i] = decoded0[i] << scale;
}
break;
case RIGHT_SIDE:
//assert(s->channels == 2);
for (i = 0; i < s->blocksize; i++)
{
decoded0[i] = (decoded0[i] + decoded1[i]) << scale;
decoded1[i] = decoded1[i] << scale;
}
break;
case MID_SIDE:
//assert(s->channels == 2);
for (i = 0; i < s->blocksize; i++)
{
int mid, side;
mid = decoded0[i];
side = decoded1[i];
#if 1 //needs to be checked but IMHO it should be binary identical
mid -= side>>1;
decoded0[i] = (mid + side) << scale;
decoded1[i] = mid << scale;
#else
mid <<= 1;
if (side & 1)
mid++;
decoded0[i] = ((mid + side) >> 1) << scale;
decoded1[i] = ((mid - side) >> 1) << scale;
#endif
}
break;
}
s->framesize = (get_bits_count(&s->gb)+7)>>3;
return 0;
}
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