rockbox/apps/codecs/libcook/cook.c
Andrew Mahone 50512cdeac Fix red: av_log2 undefined for ARM_ARCH <= 4, missing codeclib.h includes.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@23869 a1c6a512-1295-4272-9138-f99709370657
2009-12-06 04:43:23 +00:00

846 lines
27 KiB
C

/*
* COOK compatible decoder
* Copyright (c) 2003 Sascha Sommer
* Copyright (c) 2005 Benjamin Larsson
*
* 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 2.1 of the License, or (at your option) any later version.
*
* 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file cook.c
* Cook compatible decoder. Bastardization of the G.722.1 standard.
* This decoder handles RealNetworks, RealAudio G2 data.
* Cook is identified by the codec name cook in RM files.
*
* To use this decoder, a calling application must supply the extradata
* bytes provided from the RM container; 8+ bytes for mono streams and
* 16+ for stereo streams (maybe more).
*
* Codec technicalities (all this assume a buffer length of 1024):
* Cook works with several different techniques to achieve its compression.
* In the timedomain the buffer is divided into 8 pieces and quantized. If
* two neighboring pieces have different quantization index a smooth
* quantization curve is used to get a smooth overlap between the different
* pieces.
* To get to the transformdomain Cook uses a modulated lapped transform.
* The transform domain has 50 subbands with 20 elements each. This
* means only a maximum of 50*20=1000 coefficients are used out of the 1024
* available.
*/
#include <math.h>
#include <stddef.h>
#include <stdio.h>
#include <limits.h>
#include <string.h>
#include "codeclib.h"
#include "cook.h"
#include "cookdata.h"
/* the different Cook versions */
#define MONO 0x1000001
#define STEREO 0x1000002
#define JOINT_STEREO 0x1000003
#define MC_COOK 0x2000000 //multichannel Cook, not supported
#define SUBBAND_SIZE 20
#define MAX_SUBPACKETS 5
//#define COOKDEBUG
#ifndef COOKDEBUG
#undef DEBUGF
#define DEBUGF(...)
#endif
/**
* Random bit stream generator.
*/
static inline int cook_random(COOKContext *q)
{
q->random_state =
q->random_state * 214013 + 2531011; /* typical RNG numbers */
return (q->random_state/0x1000000)&1; /*>>31*/
}
#include "cook_fixpoint.h"
/* debug functions */
#ifdef COOKDEBUG
static void dump_int_table(int* table, int size, int delimiter) {
int i=0;
DEBUGF("\n[%d]: ",i);
for (i=0 ; i<size ; i++) {
DEBUGF("%d, ", table[i]);
if ((i+1)%delimiter == 0) DEBUGF("\n[%d]: ",i+1);
}
}
static void dump_short_table(short* table, int size, int delimiter) {
int i=0;
DEBUGF("\n[%d]: ",i);
for (i=0 ; i<size ; i++) {
DEBUGF("%d, ", table[i]);
if ((i+1)%delimiter == 0) DEBUGF("\n[%d]: ",i+1);
}
}
#endif
/*************** init functions ***************/
#define VLCBUFSIZE 1500
VLC_TYPE vlcbuf[21][VLCBUFSIZE][2];
static int init_cook_vlc_tables(COOKContext *q) {
int i, result;
result = 0;
for (i=0 ; i<13 ; i++) {
q->envelope_quant_index[i].table = vlcbuf[i];
q->envelope_quant_index[i].table_allocated = VLCBUFSIZE;
result |= init_vlc (&q->envelope_quant_index[i], 9, 24,
envelope_quant_index_huffbits[i], 1, 1,
envelope_quant_index_huffcodes[i], 2, 2, INIT_VLC_USE_NEW_STATIC);
}
DEBUGF("sqvh VLC init\n");
for (i=0 ; i<7 ; i++) {
q->sqvh[i].table = vlcbuf[i+13];
q->sqvh[i].table_allocated = VLCBUFSIZE;
result |= init_vlc (&q->sqvh[i], vhvlcsize_tab[i], vhsize_tab[i],
cvh_huffbits[i], 1, 1,
cvh_huffcodes[i], 2, 2, INIT_VLC_USE_NEW_STATIC);
}
if (q->nb_channels==2 && q->joint_stereo==1){
q->ccpl.table = vlcbuf[20];
q->ccpl.table_allocated = VLCBUFSIZE;
result |= init_vlc (&q->ccpl, 6, (1<<q->js_vlc_bits)-1,
ccpl_huffbits[q->js_vlc_bits-2], 1, 1,
ccpl_huffcodes[q->js_vlc_bits-2], 2, 2, INIT_VLC_USE_NEW_STATIC);
DEBUGF("Joint-stereo VLC used.\n");
}
DEBUGF("VLC tables initialized. Result = %d\n",result);
return result;
}
/*************** init functions end ***********/
/**
* Cook indata decoding, every 32 bits are XORed with 0x37c511f2.
* Why? No idea, some checksum/error detection method maybe.
*
* Out buffer size: extra bytes are needed to cope with
* padding/misalignment.
* Subpackets passed to the decoder can contain two, consecutive
* half-subpackets, of identical but arbitrary size.
* 1234 1234 1234 1234 extraA extraB
* Case 1: AAAA BBBB 0 0
* Case 2: AAAA ABBB BB-- 3 3
* Case 3: AAAA AABB BBBB 2 2
* Case 4: AAAA AAAB BBBB BB-- 1 5
*
* Nice way to waste CPU cycles.
*
* @param inbuffer pointer to byte array of indata
* @param out pointer to byte array of outdata
* @param bytes number of bytes
*/
#define DECODE_BYTES_PAD1(bytes) (3 - ((bytes)+3) % 4)
#define DECODE_BYTES_PAD2(bytes) ((bytes) % 4 + DECODE_BYTES_PAD1(2 * (bytes)))
static inline int decode_bytes(const uint8_t* inbuffer, uint8_t* out, int bytes){
int i, off;
uint32_t c;
const uint32_t* buf;
uint32_t* obuf = (uint32_t*) out;
/* FIXME: 64 bit platforms would be able to do 64 bits at a time.
* I'm too lazy though, should be something like
* for(i=0 ; i<bitamount/64 ; i++)
* (int64_t)out[i] = 0x37c511f237c511f2^be2me_64(int64_t)in[i]);
* Buffer alignment needs to be checked. */
off = (intptr_t)inbuffer & 3;
buf = (const uint32_t*) (inbuffer - off);
c = be2me_32((0x37c511f2 >> (off*8)) | (0x37c511f2 << (32-(off*8))));
bytes += 3 + off;
for (i = 0; i < bytes/4; i++)
obuf[i] = c ^ buf[i];
return off;
}
/**
* Fill the gain array for the timedomain quantization.
*
* @param q pointer to the COOKContext
* @param gaininfo[9] array of gain indexes
*/
static void decode_gain_info(GetBitContext *gb, int *gaininfo)
{
int i, n;
while (get_bits1(gb)) {}
n = get_bits_count(gb) - 1; //amount of elements*2 to update
i = 0;
while (n--) {
int index = get_bits(gb, 3);
int gain = get_bits1(gb) ? (int)get_bits(gb, 4) - 7 : -1;
while (i <= index) gaininfo[i++] = gain;
}
while (i <= 8) gaininfo[i++] = 0;
}
/**
* Create the quant index table needed for the envelope.
*
* @param q pointer to the COOKContext
* @param quant_index_table pointer to the array
*/
static void decode_envelope(COOKContext *q, int* quant_index_table) {
int i,j, vlc_index;
quant_index_table[0]= get_bits(&q->gb,6) - 6; //This is used later in categorize
for (i=1 ; i < q->total_subbands ; i++){
vlc_index=i;
if (i >= q->js_subband_start * 2) {
vlc_index-=q->js_subband_start;
} else {
vlc_index/=2;
if(vlc_index < 1) vlc_index = 1;
}
if (vlc_index>13) vlc_index = 13; //the VLC tables >13 are identical to No. 13
j = get_vlc2(&q->gb, q->envelope_quant_index[vlc_index-1].table,
q->envelope_quant_index[vlc_index-1].bits,2);
quant_index_table[i] = quant_index_table[i-1] + j - 12; //differential encoding
}
}
/**
* Calculate the category and category_index vector.
*
* @param q pointer to the COOKContext
* @param quant_index_table pointer to the array
* @param category pointer to the category array
* @param category_index pointer to the category_index array
*/
static void categorize(COOKContext *q, int* quant_index_table,
int* category, int* category_index){
int exp_idx, bias, tmpbias1, tmpbias2, bits_left, num_bits, index, v, i, j;
int exp_index2[102];
int exp_index1[102];
int tmp_categorize_array[128*2];
int tmp_categorize_array1_idx=q->numvector_size;
int tmp_categorize_array2_idx=q->numvector_size;
bits_left = q->bits_per_subpacket - get_bits_count(&q->gb);
if(bits_left > q->samples_per_channel) {
bits_left = q->samples_per_channel +
((bits_left - q->samples_per_channel)*5)/8;
//av_log(q->avctx, AV_LOG_ERROR, "bits_left = %d\n",bits_left);
}
memset(&exp_index1,0,102*sizeof(int));
memset(&exp_index2,0,102*sizeof(int));
memset(&tmp_categorize_array,0,128*2*sizeof(int));
bias=-32;
/* Estimate bias. */
for (i=32 ; i>0 ; i=i/2){
num_bits = 0;
index = 0;
for (j=q->total_subbands ; j>0 ; j--){
exp_idx = av_clip((i - quant_index_table[index] + bias) / 2, 0, 7);
index++;
num_bits+=expbits_tab[exp_idx];
}
if(num_bits >= bits_left - 32){
bias+=i;
}
}
/* Calculate total number of bits. */
num_bits=0;
for (i=0 ; i<q->total_subbands ; i++) {
exp_idx = av_clip((bias - quant_index_table[i]) / 2, 0, 7);
num_bits += expbits_tab[exp_idx];
exp_index1[i] = exp_idx;
exp_index2[i] = exp_idx;
}
tmpbias1 = tmpbias2 = num_bits;
for (j = 1 ; j < q->numvector_size ; j++) {
if (tmpbias1 + tmpbias2 > 2*bits_left) { /* ---> */
int max = -999999;
index=-1;
for (i=0 ; i<q->total_subbands ; i++){
if (exp_index1[i] < 7) {
v = (-2*exp_index1[i]) - quant_index_table[i] + bias;
if ( v >= max) {
max = v;
index = i;
}
}
}
if(index==-1)break;
tmp_categorize_array[tmp_categorize_array1_idx++] = index;
tmpbias1 -= expbits_tab[exp_index1[index]] -
expbits_tab[exp_index1[index]+1];
++exp_index1[index];
} else { /* <--- */
int min = 999999;
index=-1;
for (i=0 ; i<q->total_subbands ; i++){
if(exp_index2[i] > 0){
v = (-2*exp_index2[i])-quant_index_table[i]+bias;
if ( v < min) {
min = v;
index = i;
}
}
}
if(index == -1)break;
tmp_categorize_array[--tmp_categorize_array2_idx] = index;
tmpbias2 -= expbits_tab[exp_index2[index]] -
expbits_tab[exp_index2[index]-1];
--exp_index2[index];
}
}
memcpy(category, exp_index2, sizeof(int) * q->total_subbands );
memcpy(category_index, tmp_categorize_array+tmp_categorize_array2_idx, sizeof(int) * (q->numvector_size-1) );
}
/**
* Expand the category vector.
*
* @param q pointer to the COOKContext
* @param category pointer to the category array
* @param category_index pointer to the category_index array
*/
static inline void expand_category(COOKContext *q, int* category,
int* category_index){
int i;
for(i=0 ; i<q->num_vectors ; i++){
++category[category_index[i]];
}
}
/**
* Unpack the subband_coef_index and subband_coef_sign vectors.
*
* @param q pointer to the COOKContext
* @param category pointer to the category array
* @param subband_coef_index array of indexes to quant_centroid_tab
* @param subband_coef_sign signs of coefficients
*/
static int unpack_SQVH(COOKContext *q, int category, int* subband_coef_index,
int* subband_coef_sign) {
int i,j;
int vlc, vd ,tmp, result;
vd = vd_tab[category];
result = 0;
for(i=0 ; i<vpr_tab[category] ; i++)
{
vlc = get_vlc2(&q->gb, q->sqvh[category].table, q->sqvh[category].bits, 3);
if (q->bits_per_subpacket < get_bits_count(&q->gb))
{
vlc = 0;
result = 1;
memset(subband_coef_index, 0, sizeof(int)*vd);
memset(subband_coef_sign, 0, sizeof(int)*vd);
subband_coef_index+=vd;
subband_coef_sign+=vd;
}
else
{
for(j=vd-1 ; j>=0 ; j--){
tmp = (vlc * invradix_tab[category])/0x100000;
subband_coef_index[j] = vlc - tmp * (kmax_tab[category]+1);
vlc = tmp;
}
for(j=0 ; j<vd ; j++)
{
if (*subband_coef_index++) {
if(get_bits_count(&q->gb) < q->bits_per_subpacket) {
*subband_coef_sign++ = get_bits1(&q->gb);
} else {
result=1;
*subband_coef_sign++=0;
}
} else {
*subband_coef_sign++=0;
}
}
}
}
return result;
}
/**
* Fill the mlt_buffer with mlt coefficients.
*
* @param q pointer to the COOKContext
* @param category pointer to the category array
* @param quant_index_table pointer to the array
* @param mlt_buffer pointer to mlt coefficients
*/
static void decode_vectors(COOKContext* q, int* category,
int *quant_index_table, REAL_T* mlt_buffer){
/* A zero in this table means that the subband coefficient is
random noise coded. */
int subband_coef_index[SUBBAND_SIZE];
/* A zero in this table means that the subband coefficient is a
positive multiplicator. */
int subband_coef_sign[SUBBAND_SIZE];
int band, j;
int index=0;
for(band=0 ; band<q->total_subbands ; band++){
index = category[band];
if(category[band] < 7){
if(unpack_SQVH(q, category[band], subband_coef_index, subband_coef_sign)){
index=7;
for(j=0 ; j<q->total_subbands ; j++) category[band+j]=7;
}
}
if(index>=7) {
memset(subband_coef_index, 0, sizeof(subband_coef_index));
memset(subband_coef_sign, 0, sizeof(subband_coef_sign));
}
q->scalar_dequant(q, index, quant_index_table[band],
subband_coef_index, subband_coef_sign,
&mlt_buffer[band * SUBBAND_SIZE]);
}
if(q->total_subbands*SUBBAND_SIZE >= q->samples_per_channel){
return;
} /* FIXME: should this be removed, or moved into loop above? */
}
/**
* function for decoding mono data
*
* @param q pointer to the COOKContext
* @param mlt_buffer pointer to mlt coefficients
*/
static void mono_decode(COOKContext *q, REAL_T* mlt_buffer) {
int category_index[128];
int quant_index_table[102];
int category[128];
memset(&category, 0, 128*sizeof(int));
memset(&category_index, 0, 128*sizeof(int));
decode_envelope(q, quant_index_table);
q->num_vectors = get_bits(&q->gb,q->log2_numvector_size);
categorize(q, quant_index_table, category, category_index);
expand_category(q, category, category_index);
decode_vectors(q, category, quant_index_table, mlt_buffer);
}
/**
* function for getting the jointstereo coupling information
*
* @param q pointer to the COOKContext
* @param decouple_tab decoupling array
*
*/
static void decouple_info(COOKContext *q, int* decouple_tab){
int length, i;
if(get_bits1(&q->gb)) {
if(cplband[q->js_subband_start] > cplband[q->subbands-1]) return;
length = cplband[q->subbands-1] - cplband[q->js_subband_start] + 1;
for (i=0 ; i<length ; i++) {
decouple_tab[cplband[q->js_subband_start] + i] = get_vlc2(&q->gb, q->ccpl.table, q->ccpl.bits, 2);
}
return;
}
if(cplband[q->js_subband_start] > cplband[q->subbands-1]) return;
length = cplband[q->subbands-1] - cplband[q->js_subband_start] + 1;
for (i=0 ; i<length ; i++) {
decouple_tab[cplband[q->js_subband_start] + i] = get_bits(&q->gb, q->js_vlc_bits);
}
return;
}
/**
* function for decoding joint stereo data
*
* @param q pointer to the COOKContext
* @param mlt_buffer1 pointer to left channel mlt coefficients
* @param mlt_buffer2 pointer to right channel mlt coefficients
*/
static void joint_decode(COOKContext *q, REAL_T* mlt_buffer1,
REAL_T* mlt_buffer2) {
int i;
int decouple_tab[SUBBAND_SIZE];
REAL_T *decode_buffer = q->decode_buffer_0;
int idx;
memset(decouple_tab, 0, sizeof(decouple_tab));
memset(decode_buffer, 0, sizeof(decode_buffer));
/* Make sure the buffers are zeroed out. */
memset(mlt_buffer1,0, 1024*sizeof(REAL_T));
memset(mlt_buffer2,0, 1024*sizeof(REAL_T));
decouple_info(q, decouple_tab);
mono_decode(q, decode_buffer);
/* The two channels are stored interleaved in decode_buffer. */
REAL_T * mlt_buffer1_end = mlt_buffer1 + (q->js_subband_start*SUBBAND_SIZE);
while(mlt_buffer1 < mlt_buffer1_end)
{
memcpy(mlt_buffer1,decode_buffer,sizeof(REAL_T)*SUBBAND_SIZE);
memcpy(mlt_buffer2,decode_buffer+20,sizeof(REAL_T)*SUBBAND_SIZE);
mlt_buffer1 += 20;
mlt_buffer2 += 20;
decode_buffer += 40;
}
/* When we reach js_subband_start (the higher frequencies)
the coefficients are stored in a coupling scheme. */
idx = (1 << q->js_vlc_bits) - 1;
for (i=q->js_subband_start ; i<q->subbands ; i++) {
int i1 = decouple_tab[cplband[i]];
int i2 = idx - i1 - 1;
mlt_buffer1_end = mlt_buffer1 + SUBBAND_SIZE;
while(mlt_buffer1 < mlt_buffer1_end)
{
*mlt_buffer1++ = cplscale_math(*decode_buffer, q->js_vlc_bits, i1);
*mlt_buffer2++ = cplscale_math(*decode_buffer++, q->js_vlc_bits, i2);
}
mlt_buffer1 += (20-SUBBAND_SIZE);
mlt_buffer2 += (20-SUBBAND_SIZE);
decode_buffer += (20-SUBBAND_SIZE);
}
}
/**
* First part of subpacket decoding:
* decode raw stream bytes and read gain info.
*
* @param q pointer to the COOKContext
* @param inbuffer pointer to raw stream data
* @param gain_ptr array of current/prev gain pointers
*/
#define FFSWAP(type,a,b) do{type SWAP_tmp= b; b= a; a= SWAP_tmp;}while(0)
static inline void
decode_bytes_and_gain(COOKContext *q, const uint8_t *inbuffer,
cook_gains *gains_ptr)
{
int offset;
offset = decode_bytes(inbuffer, q->decoded_bytes_buffer,
q->bits_per_subpacket/8);
init_get_bits(&q->gb, q->decoded_bytes_buffer + offset,
q->bits_per_subpacket);
decode_gain_info(&q->gb, gains_ptr->now);
/* Swap current and previous gains */
FFSWAP(int *, gains_ptr->now, gains_ptr->previous);
}
/**
* Final part of subpacket decoding:
* Apply modulated lapped transform, gain compensation,
* clip and convert to integer.
*
* @param q pointer to the COOKContext
* @param decode_buffer pointer to the mlt coefficients
* @param gain_ptr array of current/prev gain pointers
* @param previous_buffer pointer to the previous buffer to be used for overlapping
* @param out pointer to the output buffer
* @param chan 0: left or single channel, 1: right channel
*/
static void
mlt_compensate_output(COOKContext *q, REAL_T *decode_buffer,
cook_gains *gains, REAL_T *previous_buffer,
int16_t *out, int chan)
{
REAL_T *buffer = q->mono_mdct_output;
int i;
imlt_math(q, decode_buffer);
/* Overlap with the previous block. */
overlap_math(q, gains->previous[0], previous_buffer);
/* Apply gain profile */
for (i = 0; i < 8; i++) {
if (gains->now[i] || gains->now[i + 1])
interpolate_math(q, &buffer[q->samples_per_channel/8 * i],
gains->now[i], gains->now[i + 1]);
}
/* Save away the current to be previous block. */
memcpy(previous_buffer, buffer+q->samples_per_channel,
sizeof(REAL_T)*q->samples_per_channel);
output_math(q, out, chan);
}
/**
* Cook subpacket decoding. This function returns one decoded subpacket,
* usually 1024 samples per channel.
*
* @param q pointer to the COOKContext
* @param inbuffer pointer to the inbuffer
* @param sub_packet_size subpacket size
* @param outbuffer pointer to the outbuffer
*/
static int decode_subpacket(COOKContext *q, const uint8_t *inbuffer,
int sub_packet_size, int16_t *outbuffer) {
/* packet dump */
// for (i=0 ; i<sub_packet_size ; i++) {
// DEBUGF("%02x", inbuffer[i]);
// }
// DEBUGF("\n");
decode_bytes_and_gain(q, inbuffer, &q->gains1);
if (q->joint_stereo) {
joint_decode(q, q->decode_buffer_1, q->decode_buffer_2);
} else {
mono_decode(q, q->decode_buffer_1);
if (q->nb_channels == 2) {
decode_bytes_and_gain(q, inbuffer + sub_packet_size/2, &q->gains2);
mono_decode(q, q->decode_buffer_2);
}
}
mlt_compensate_output(q, q->decode_buffer_1, &q->gains1,
q->mono_previous_buffer1, outbuffer, 0);
if (q->nb_channels == 2) {
if (q->joint_stereo) {
mlt_compensate_output(q, q->decode_buffer_2, &q->gains1,
q->mono_previous_buffer2, outbuffer, 1);
} else {
mlt_compensate_output(q, q->decode_buffer_2, &q->gains2,
q->mono_previous_buffer2, outbuffer, 1);
}
}
return q->samples_per_frame * sizeof(int16_t);
}
/**
* Cook frame decoding
*
* @param rmctx pointer to the RMContext
*/
int cook_decode_frame(RMContext *rmctx,COOKContext *q,
int16_t *outbuffer, int *data_size,
const uint8_t *inbuffer, int buf_size) {
//COOKContext *q = avctx->priv_data;
//COOKContext *q;
if (buf_size < rmctx->block_align)
return buf_size;
*data_size = decode_subpacket(q, inbuffer, rmctx->block_align, outbuffer);
/* Discard the first two frames: no valid audio. */
if (rmctx->frame_number < 2) *data_size = 0;
return rmctx->block_align;
}
#ifdef COOKDEBUG
static void dump_cook_context(COOKContext *q)
{
//int i=0;
#define PRINT(a,b) DEBUGF(" %s = %d\n", a, b);
DEBUGF("COOKextradata\n");
DEBUGF("cookversion=%x\n",q->cookversion);
if (q->cookversion > STEREO) {
PRINT("js_subband_start",q->js_subband_start);
PRINT("js_vlc_bits",q->js_vlc_bits);
}
PRINT("nb_channels",q->nb_channels);
PRINT("bit_rate",q->bit_rate);
PRINT("sample_rate",q->sample_rate);
PRINT("samples_per_channel",q->samples_per_channel);
PRINT("samples_per_frame",q->samples_per_frame);
PRINT("subbands",q->subbands);
PRINT("random_state",q->random_state);
PRINT("js_subband_start",q->js_subband_start);
PRINT("log2_numvector_size",q->log2_numvector_size);
PRINT("numvector_size",q->numvector_size);
PRINT("total_subbands",q->total_subbands);
}
#endif
/**
* Cook initialization
*/
int cook_decode_init(RMContext *rmctx, COOKContext *q)
{
/* cook extradata */
q->cookversion = rm_get_uint32be(rmctx->codec_extradata);
q->samples_per_frame = rm_get_uint16be(&rmctx->codec_extradata[4]);
q->subbands = rm_get_uint16be(&rmctx->codec_extradata[6]);
q->extradata_size = rmctx->extradata_size;
if (q->extradata_size >= 16){
q->js_subband_start = rm_get_uint16be(&rmctx->codec_extradata[12]);
q->js_vlc_bits = rm_get_uint16be(&rmctx->codec_extradata[14]);
}
/* Take data from the RMContext (RM container). */
q->sample_rate = rmctx->sample_rate;
q->nb_channels = rmctx->nb_channels;
q->bit_rate = rmctx->bit_rate;
/* Initialize RNG. */
q->random_state = 0;
/* Initialize extradata related variables. */
q->samples_per_channel = q->samples_per_frame >> (q->nb_channels-1);
q->bits_per_subpacket = rmctx->block_align * 8;
/* Initialize default data states. */
q->log2_numvector_size = 5;
q->total_subbands = q->subbands;
/* Initialize version-dependent variables */
DEBUGF("q->cookversion=%x\n",q->cookversion);
q->joint_stereo = 0;
switch (q->cookversion) {
case MONO:
if (q->nb_channels != 1) {
DEBUGF("Container channels != 1, report sample!\n");
return -1;
}
DEBUGF("MONO\n");
break;
case STEREO:
if (q->nb_channels != 1) {
q->bits_per_subpacket = q->bits_per_subpacket/2;
}
DEBUGF("STEREO\n");
break;
case JOINT_STEREO:
if (q->nb_channels != 2) {
DEBUGF("Container channels != 2, report sample!\n");
return -1;
}
DEBUGF("JOINT_STEREO\n");
if (q->extradata_size >= 16){
q->total_subbands = q->subbands + q->js_subband_start;
q->joint_stereo = 1;
}
if (q->samples_per_channel > 256) {
q->log2_numvector_size = 6;
}
if (q->samples_per_channel > 512) {
q->log2_numvector_size = 7;
}
break;
case MC_COOK:
DEBUGF("MC_COOK not supported!\n");
return -1;
break;
default:
DEBUGF("Unknown Cook version, report sample!\n");
return -1;
break;
}
/* Initialize variable relations */
q->numvector_size = (1 << q->log2_numvector_size);
/* Generate tables */
if (init_cook_vlc_tables(q) != 0)
return -1;
if(rmctx->block_align >= UINT16_MAX/2)
return -1;
q->gains1.now = q->gain_1;
q->gains1.previous = q->gain_2;
q->gains2.now = q->gain_3;
q->gains2.previous = q->gain_4;
/* Initialize COOK signal arithmetic handling */
if (1) {
q->scalar_dequant = scalar_dequant_math;
q->interpolate = interpolate_math;
}
/* Try to catch some obviously faulty streams, othervise it might be exploitable */
if (q->total_subbands > 53) {
DEBUGF("total_subbands > 53, report sample!\n");
return -1;
}
if (q->subbands > 50) {
DEBUGF("subbands > 50, report sample!\n");
return -1;
}
if ((q->samples_per_channel == 256) || (q->samples_per_channel == 512) || (q->samples_per_channel == 1024)) {
} else {
DEBUGF("unknown amount of samples_per_channel = %d, report sample!\n",q->samples_per_channel);
return -1;
}
if ((q->js_vlc_bits > 6) || (q->js_vlc_bits < 0)) {
DEBUGF("q->js_vlc_bits = %d, only >= 0 and <= 6 allowed!\n",q->js_vlc_bits);
return -1;
}
#ifdef COOKDEBUG
dump_cook_context(q);
#endif
return 0;
}