/*
* ATRAC9 decoder
* Copyright (c) 2018 Rostislav Pehlivanov <atomnuker@gmail.com>
*
* 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
*/
#include "internal.h"
#include "get_bits.h"
#include "fft.h"
#include "atrac9tab.h"
#include "libavutil/lfg.h"
#include "libavutil/float_dsp.h"
typedef struct ATRAC9ChannelData {
int band_ext;
int q_unit_cnt;
int band_ext_data[4];
int32_t scalefactors[31];
int32_t scalefactors_prev[31];
int precision_coarse[30];
int precision_fine[30];
int precision_mask[30];
int codebookset[30];
int32_t q_coeffs_coarse[256];
int32_t q_coeffs_fine[256];
DECLARE_ALIGNED(32, float, coeffs )[256];
DECLARE_ALIGNED(32, float, prev_win)[128];
} ATRAC9ChannelData;
typedef struct ATRAC9BlockData {
ATRAC9ChannelData channel[2];
/* Base */
int band_count;
int q_unit_cnt;
int q_unit_cnt_prev;
/* Stereo block only */
int stereo_q_unit;
/* Band extension only */
int has_band_ext;
int has_band_ext_data;
int band_ext_q_unit;
/* Gradient */
int grad_mode;
int grad_boundary;
int gradient[31];
/* Stereo */
int cpe_base_channel;
int is_signs[30];
} ATRAC9BlockData;
typedef struct ATRAC9Context {
AVCodecContext *avctx;
AVFloatDSPContext *fdsp;
FFTContext imdct;
ATRAC9BlockData block[5];
AVLFG lfg;
/* Set on init */
int frame_log2;
int avg_frame_size;
int frame_count;
int samplerate_idx;
const ATRAC9BlockConfig *block_config;
/* Generated on init */
VLC sf_vlc[2][8]; /* Signed/unsigned, length */
VLC coeff_vlc[2][8][4]; /* Cookbook, precision, cookbook index */
uint8_t alloc_curve[48][48];
DECLARE_ALIGNED(32, float, imdct_win)[256];
DECLARE_ALIGNED(32, float, temp)[256];
} ATRAC9Context;
static inline int parse_gradient(ATRAC9Context *s, ATRAC9BlockData *b,
GetBitContext *gb)
{
int grad_range[2];
int grad_value[2];
int values, sign, base;
uint8_t *curve;
float scale;
b->grad_mode = get_bits(gb, 2);
if (b->grad_mode) {
grad_range[0] = get_bits(gb, 5);
grad_range[1] = 31;
grad_value[0] = get_bits(gb, 5);
grad_value[1] = 31;
} else {
grad_range[0] = get_bits(gb, 6);
grad_range[1] = get_bits(gb, 6) + 1;
grad_value[0] = get_bits(gb, 5);
grad_value[1] = get_bits(gb, 5);
}
b->grad_boundary = get_bits(gb, 4);
if (grad_range[0] >= grad_range[1] || grad_range[1] > 47)
return AVERROR_INVALIDDATA;
if (grad_value[0] > 31 || grad_value[1] > 31)
return AVERROR_INVALIDDATA;
if (b->grad_boundary > b->q_unit_cnt)
return AVERROR_INVALIDDATA;
values = grad_value[1] - grad_value[0];
sign = 1 - 2*(values < 0);
base = grad_value[0] + sign;
scale = (FFABS(values) - 1) / 31.0f;
curve = s->alloc_curve[grad_range[1] - grad_range[0] - 1];
for (int i = 0; i <= b->q_unit_cnt; i++)
b->gradient[i] = grad_value[i >= grad_range[0]];
for (int i = grad_range[0]; i < grad_range[1]; i++)
b->gradient[i] = base + sign*((int)(scale*curve[i - grad_range[0]]));
return 0;
}
static inline void calc_precision(ATRAC9Context *s, ATRAC9BlockData *b,
ATRAC9ChannelData *c)
{
memset(c->precision_mask, 0, sizeof(c->precision_mask));
for (int i = 1; i < b->q_unit_cnt; i++) {
const int delta = FFABS(c->scalefactors[i] - c->scalefactors[i - 1]) - 1;
if (delta > 0) {
const int neg = c->scalefactors[i - 1] > c->scalefactors[i];
c->precision_mask[i - neg] += FFMIN(delta, 5);
}
}
if (b->grad_mode) {
for (int i = 0; i < b->q_unit_cnt; i++) {
c->precision_coarse[i] = c->scalefactors[i];
c->precision_coarse[i] += c->precision_mask[i] - b->gradient[i];
if (c->precision_coarse[i] < 0)
continue;
switch (b->grad_mode) {
case 1:
c->precision_coarse[i] >>= 1;
break;
case 2:
c->precision_coarse[i] = (3 * c->precision_coarse[i]) >> 3;
break;
case 3:
c->precision_coarse[i] >>= 2;
break;
}
}
} else {
for (int i = 0; i < b->q_unit_cnt; i++)
c->precision_coarse[i] = c->scalefactors[i] - b->gradient[i];
}
for (int i = 0; i < b->q_unit_cnt; i++)
c->precision_coarse[i] = FFMAX(c->precision_coarse[i], 1);
for (int i = 0; i < b->grad_boundary; i++)
c->precision_coarse[i]++;
for (int i = 0; i < b->q_unit_cnt; i++) {
c->precision_fine[i] = 0;
if (c->precision_coarse[i] > 15) {
c->precision_fine[i] = c->precision_coarse[i] - 15;
c->precision_coarse[i] = 15;
}
}
}
static inline int parse_band_ext(ATRAC9Context *s, ATRAC9BlockData *b,
GetBitContext *gb, int stereo)
{
int ext_band = 0;
if (b->has_band_ext) {
ext_band = at9_tab_band_ext_group[b->q_unit_cnt - 13][2];
if (stereo) {
b->channel[1].band_ext = get_bits(gb, 2);
b->channel[1].band_ext = ext_band > 2 ? b->channel[1].band_ext : 4;
} else {
skip_bits1(gb);
}
}
b->has_band_ext_data = get_bits1(gb);
if (!b->has_band_ext_data)
return 0;
if (!b->has_band_ext) {
skip_bits(gb, 2);
skip_bits_long(gb, get_bits(gb, 5));
return 0;
}
b->channel[0].band_ext = get_bits(gb, 2);
b->channel[0].band_ext = ext_band > 2 ? b->channel[0].band_ext : 4;
if (!get_bits(gb, 5))
return 0;
for (int i = 0; i <= stereo; i++) {
ATRAC9ChannelData *c = &b->channel[i];
const int count = at9_tab_band_ext_cnt[c->band_ext][ext_band];
for (int j = 0; j < count; j++) {
int len = at9_tab_band_ext_lengths[c->band_ext][ext_band][j];
c->band_ext_data[j] = get_bits(gb, len);
}
}
return 0;
}
static inline int read_scalefactors(ATRAC9Context *s, ATRAC9BlockData *b,
ATRAC9ChannelData *c, GetBitContext *gb,
int channel_idx, int first_in_pkt)
{
static const int mode_map[2][4] = { { 0, 1, 2, 3 }, { 0, 2, 3, 4 } };
const int mode = mode_map[channel_idx][get_bits(gb, 2)];
memset(c->scalefactors, 0, sizeof(c->scalefactors));
if (first_in_pkt && (mode == 4 || ((mode == 3) && !channel_idx))) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid scalefactor coding mode!\n");
return AVERROR_INVALIDDATA;
}
switch (mode) {
case 0: { /* VLC delta offset */
const uint8_t *sf_weights = at9_tab_sf_weights[get_bits(gb, 3)];
const int base = get_bits(gb, 5);
const int len = get_bits(gb, 2) + 3;
const VLC *tab = &s->sf_vlc[0][len];
c->scalefactors[0] = get_bits(gb, len);
for (int i = 1; i < b->band_ext_q_unit; i++) {
int val = c->scalefactors[i - 1] + get_vlc2(gb, tab->table, 9, 2);
c->scalefactors[i] = val & ((1 << len) - 1);
}
for (int i = 0; i < b->band_ext_q_unit; i++)
c->scalefactors[i] += base - sf_weights[i];
break;
}
case 1: { /* CLC offset */
const int len = get_bits(gb, 2) + 2;
const int base = len < 5 ? get_bits(gb, 5) : 0;
for (int i = 0; i < b->band_ext_q_unit; i++)
c->scalefactors[i] = base + get_bits(gb, len);
break;
}
case 2:
case 4: { /* VLC dist to baseline */
const int *baseline = mode == 4 ? c->scalefactors_prev :
channel_idx ? b->channel[0].scalefactors :
c->scalefactors_prev;
const int baseline_len = mode == 4 ? b->q_unit_cnt_prev :
channel_idx ? b->band_ext_q_unit :
b->q_unit_cnt_prev;
const int len = get_bits(gb, 2) + 2;
const int unit_cnt = FFMIN(b->band_ext_q_unit, baseline_len);
const VLC *tab = &s->sf_vlc[1][len];
for (int i = 0; i < unit_cnt; i++) {
int dist = get_vlc2(gb, tab->table, 9, 2);
c->scalefactors[i] = baseline[i] + dist;
}
for (int i = unit_cnt; i < b->band_ext_q_unit; i++)
c->scalefactors[i] = get_bits(gb, 5);
break;
}
case 3: { /* VLC offset with baseline */
const int *baseline = channel_idx ? b->channel[0].scalefactors :
c->scalefactors_prev;
const int baseline_len = channel_idx ? b->band_ext_q_unit :
b->q_unit_cnt_prev;
const int base = get_bits(gb, 5) - (1 << (5 - 1));
const int len = get_bits(gb, 2) + 1;
const int unit_cnt = FFMIN(b->band_ext_q_unit, baseline_len);
const VLC *tab = &s->sf_vlc[0][len];
c->scalefactors[0] = get_bits(gb, len);
for (int i = 1; i < unit_cnt; i++) {
int val = c->scalefactors[i - 1] + get_vlc2(gb, tab->table, 9, 2);
c->scalefactors[i] = val & ((1 << len) - 1);
}
for (int i = 0; i < unit_cnt; i++)
c->scalefactors[i] += base + baseline[i];
for (int i = unit_cnt; i < b->band_ext_q_unit; i++)
c->scalefactors[i] = get_bits(gb, 5);
break;
}
}
for (int i = 0; i < b->band_ext_q_unit; i++)
if (c->scalefactors[i] < 0 || c->scalefactors[i] > 31)
return AVERROR_INVALIDDATA;
memcpy(c->scalefactors_prev, c->scalefactors, sizeof(c->scalefactors));
return 0;
}
static inline void calc_codebook_idx(ATRAC9Context *s, ATRAC9BlockData *b,
ATRAC9ChannelData *c)
{
int avg = 0;
const int last_sf = c->scalefactors[c->q_unit_cnt];
memset(c->codebookset, 0, sizeof(c->codebookset));
if (c->q_unit_cnt <= 1)
return;
if (s->samplerate_idx > 7)
return;
c->scalefactors[c->q_unit_cnt] = c->scalefactors[c->q_unit_cnt - 1];
if (c->q_unit_cnt > 12) {
for (int i = 0; i < 12; i++)
avg += c->scalefactors[i];
avg = (avg + 6) / 12;
}
for (int i = 8; i < c->q_unit_cnt; i++) {
const int prev = c->scalefactors[i - 1];
const int cur = c->scalefactors[i ];
const int next = c->scalefactors[i + 1];
const int min = FFMIN(prev, next);
if ((cur - min >= 3 || 2*cur - prev - next >= 3))
c->codebookset[i] = 1;
}
for (int i = 12; i < c->q_unit_cnt; i++) {
const int cur = c->scalefactors[i];
const int cnd = at9_q_unit_to_coeff_cnt[i] == 16;
const int min = FFMIN(c->scalefactors[i + 1], c->scalefactors[i - 1]);
if (c->codebookset[i])
continue;
c->codebookset[i] = (((cur - min) >= 2) && (cur >= (avg - cnd)));
}
c->scalefactors[c->q_unit_cnt] = last_sf;
}
static inline void read_coeffs_coarse(ATRAC9Context *s, ATRAC9BlockData *b,
ATRAC9ChannelData *c, GetBitContext *gb)
{
const int max_prec = s->samplerate_idx > 7 ? 1 : 7;
memset(c->q_coeffs_coarse, 0, sizeof(c->q_coeffs_coarse));
for (int i = 0; i < c->q_unit_cnt; i++) {
int *coeffs = &c->q_coeffs_coarse[at9_q_unit_to_coeff_idx[i]];
const int bands = at9_q_unit_to_coeff_cnt[i];
const int prec = c->precision_coarse[i] + 1;
if (prec <= max_prec) {
const int cb = c->codebookset[i];
const int cbi = at9_q_unit_to_codebookidx[i];
const VLC *tab = &s->coeff_vlc[cb][prec][cbi];
const HuffmanCodebook *huff = &at9_huffman_coeffs[cb][prec][cbi];
const int groups = bands >> huff->value_cnt_pow;
for (int j = 0; j < groups; j++) {
uint16_t val = get_vlc2(gb, tab->table, 9, huff->max_bit_size);
for (int k = 0; k < huff->value_cnt; k++) {
coeffs[k] = sign_extend(val, huff->value_bits);
val >>= huff->value_bits;
}
coeffs += huff->value_cnt;
}
} else {
for (int j = 0; j < bands; j++)
coeffs[j] = sign_extend(get_bits(gb, prec), prec);
}
}
}
static inline void read_coeffs_fine(ATRAC9Context *s, ATRAC9BlockData *b,
ATRAC9ChannelData *c, GetBitContext *gb)
{
memset(c->q_coeffs_fine, 0, sizeof(c->q_coeffs_fine));
for (int i = 0; i < c->q_unit_cnt; i++) {
const int start = at9_q_unit_to_coeff_idx[i + 0];
const int end = at9_q_unit_to_coeff_idx[i + 1];
const int len = c->precision_fine[i] + 1;
if (c->precision_fine[i] <= 0)
continue;
for (int j = start; j < end; j++)
c->q_coeffs_fine[j] = sign_extend(get_bits(gb, len), len);
}
}
static inline void dequantize(ATRAC9Context *s, ATRAC9BlockData *b,
ATRAC9ChannelData *c)
{
memset(c->coeffs, 0, sizeof(c->coeffs));
for (int i = 0; i < c->q_unit_cnt; i++) {
const int start = at9_q_unit_to_coeff_idx[i + 0];
const int end = at9_q_unit_to_coeff_idx[i + 1];
const float coarse_c = at9_quant_step_coarse[c->precision_coarse[i]];
const float fine_c = at9_quant_step_fine[c->precision_fine[i]];
for (int j = start; j < end; j++) {
const float vc = c->q_coeffs_coarse[j] * coarse_c;
const float vf = c->q_coeffs_fine[j] * fine_c;
c->coeffs[j] = vc + vf;
}
}
}
static inline void apply_intensity_stereo(ATRAC9Context *s, ATRAC9BlockData *b,
const int stereo)
{
float *src = b->channel[ b->cpe_base_channel].coeffs;
float *dst = b->channel[!b->cpe_base_channel].coeffs;
if (!stereo)
return;
if (b->q_unit_cnt <= b->stereo_q_unit)
return;
for (int i = b->stereo_q_unit; i < b->q_unit_cnt; i++) {
const int sign = b->is_signs[i];
const int start = at9_q_unit_to_coeff_idx[i + 0];
const int end = at9_q_unit_to_coeff_idx[i + 1];
for (int j = start; j < end; j++)
dst[j] = sign*src[j];
}
}
static inline void apply_scalefactors(ATRAC9Context *s, ATRAC9BlockData *b,
const int stereo)
{
for (int i = 0; i <= stereo; i++) {
float *coeffs = b->channel[i].coeffs;
for (int j = 0; j < b->q_unit_cnt; j++) {
const int start = at9_q_unit_to_coeff_idx[j + 0];
const int end = at9_q_unit_to_coeff_idx[j + 1];
const int scalefactor = b->channel[i].scalefactors[j];
const float scale = at9_scalefactor_c[scalefactor];
for (int k = start; k < end; k++)
coeffs[k] *= scale;
}
}
}
static inline void fill_with_noise(ATRAC9Context *s, ATRAC9ChannelData *c,
int start, int count)
{
float maxval = 0.0f;
for (int i = 0; i < count; i += 2) {
double tmp[2];
av_bmg_get(&s->lfg, tmp);
c->coeffs[start + i + 0] = tmp[0];
c->coeffs[start + i + 1] = tmp[1];
maxval = FFMAX(FFMAX(FFABS(tmp[0]), FFABS(tmp[1])), maxval);
}
/* Normalize */
for (int i = 0; i < count; i++)
c->coeffs[start + i] /= maxval;
}
static inline void scale_band_ext_coeffs(ATRAC9ChannelData *c, float sf[6],
const int s_unit, const int e_unit)
{
for (int i = s_unit; i < e_unit; i++) {
const int start = at9_q_unit_to_coeff_idx[i + 0];
const int end = at9_q_unit_to_coeff_idx[i + 1];
for (int j = start; j < end; j++)
c->coeffs[j] *= sf[i - s_unit];
}
}
static inline void apply_band_extension(ATRAC9Context *s, ATRAC9BlockData *b,
const int stereo)
{
const int g_units[4] = { /* A, B, C, total units */
b->q_unit_cnt,
at9_tab_band_ext_group[b->q_unit_cnt - 13][0],
at9_tab_band_ext_group[b->q_unit_cnt - 13][1],
FFMAX(g_units[2], 22),
};
const int g_bins[4] = { /* A, B, C, total bins */
at9_q_unit_to_coeff_idx[g_units[0]],
at9_q_unit_to_coeff_idx[g_units[1]],
at9_q_unit_to_coeff_idx[g_units[2]],
at9_q_unit_to_coeff_idx[g_units[3]],
};
if (!b->has_band_ext || !b->has_band_ext_data)
return;
for (int ch = 0; ch <= stereo; ch++) {
ATRAC9ChannelData *c = &b->channel[ch];
/* Mirror the spectrum */
for (int i = 0; i < 3; i++)
for (int j = 0; j < (g_bins[i + 1] - g_bins[i + 0]); j++)
c->coeffs[g_bins[i] + j] = c->coeffs[g_bins[i] - j - 1];
switch (c->band_ext) {
case 0: {
float sf[6] = { 0.0f };
const int l = g_units[3] - g_units[0] - 1;
const int n_start = at9_q_unit_to_coeff_idx[g_units[3] - 1];
const int n_cnt = at9_q_unit_to_coeff_cnt[g_units[3] - 1];
switch (at9_tab_band_ext_group[b->q_unit_cnt - 13][2]) {
case 3:
sf[0] = at9_band_ext_scales_m0[0][0][c->band_ext_data[0]];
sf[1] = at9_band_ext_scales_m0[0][1][c->band_ext_data[0]];
sf[2] = at9_band_ext_scales_m0[0][2][c->band_ext_data[1]];
sf[3] = at9_band_ext_scales_m0[0][3][c->band_ext_data[2]];
sf[4] = at9_band_ext_scales_m0[0][4][c->band_ext_data[3]];
break;
case 4:
sf[0] = at9_band_ext_scales_m0[1][0][c->band_ext_data[0]];
sf[1] = at9_band_ext_scales_m0[1][1][c->band_ext_data[0]];
sf[2] = at9_band_ext_scales_m0[1][2][c->band_ext_data[1]];
sf[3] = at9_band_ext_scales_m0[1][3][c->band_ext_data[2]];
sf[4] = at9_band_ext_scales_m0[1][4][c->band_ext_data[3]];
break;
case 5:
sf[0] = at9_band_ext_scales_m0[2][0][c->band_ext_data[0]];
sf[1] = at9_band_ext_scales_m0[2][1][c->band_ext_data[1]];
sf[2] = at9_band_ext_scales_m0[2][2][c->band_ext_data[1]];
break;
}
sf[l] = at9_scalefactor_c[c->scalefactors[g_units[0]]];
fill_with_noise(s, c, n_start, n_cnt);
scale_band_ext_coeffs(c, sf, g_units[0], g_units[3]);
break;
}
case 1: {
float sf[6];
for (int i = g_units[0]; i < g_units[3]; i++)
sf[i - g_units[0]] = at9_scalefactor_c[c->scalefactors[i]];
fill_with_noise(s, c, g_bins[0], g_bins[3] - g_bins[0]);
scale_band_ext_coeffs(c, sf, g_units[0], g_units[3]);
break;
}
case 2: {
const float g_sf[2] = {
at9_band_ext_scales_m2[c->band_ext_data[0]],
at9_band_ext_scales_m2[c->band_ext_data[1]],
};
for (int i = 0; i < 2; i++)
for (int j = g_bins[i + 0]; j < g_bins[i + 1]; j++)
c->coeffs[j] *= g_sf[i];
break;
}
case 3: {
float scale = at9_band_ext_scales_m3[c->band_ext_data[0]][0];
float rate = at9_band_ext_scales_m3[c->band_ext_data[1]][1];
rate = pow(2, rate);
for (int i = g_bins[0]; i < g_bins[3]; i++) {
scale *= rate;
c->coeffs[i] *= scale;
}
break;
}
case 4: {
const float m = at9_band_ext_scales_m4[c->band_ext_data[0]];
const float g_sf[3] = { 0.7079468f*m, 0.5011902f*m, 0.3548279f*m };
for (int i = 0; i < 3; i++)
for (int j = g_bins[i + 0]; j < g_bins[i + 1]; j++)
c->coeffs[j] *= g_sf[i];
break;
}
}
}
}
static int atrac9_decode_block(ATRAC9Context *s, GetBitContext *gb,
ATRAC9BlockData *b, AVFrame *frame,
int frame_idx, int block_idx)
{
const int first_in_pkt = !get_bits1(gb);
const int reuse_params = get_bits1(gb);
const int stereo = s->block_config->type[block_idx] == ATRAC9_BLOCK_TYPE_CPE;
if (s->block_config->type[block_idx] == ATRAC9_BLOCK_TYPE_LFE) {
ATRAC9ChannelData *c = &b->channel[0];
const int precision = reuse_params ? 8 : 4;
c->q_unit_cnt = b->q_unit_cnt = 2;
memset(c->scalefactors, 0, sizeof(c->scalefactors));
memset(c->q_coeffs_fine, 0, sizeof(c->q_coeffs_fine));
memset(c->q_coeffs_coarse, 0, sizeof(c->q_coeffs_coarse));
for (int i = 0; i < b->q_unit_cnt; i++) {
c->scalefactors[i] = get_bits(gb, 5);
c->precision_coarse[i] = precision;
c->precision_fine[i] = 0;
}
for (int i = 0; i < c->q_unit_cnt; i++) {
const int start = at9_q_unit_to_coeff_idx[i + 0];
const int end = at9_q_unit_to_coeff_idx[i + 1];
for (int j = start; j < end; j++)
c->q_coeffs_coarse[j] = get_bits(gb, c->precision_coarse[i] + 1);
}
dequantize (s, b, c);
apply_scalefactors(s, b, 0);
goto imdct;
}
if (first_in_pkt && reuse_params) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid block flags!\n");
return AVERROR_INVALIDDATA;
}
/* Band parameters */
if (!reuse_params) {
int stereo_band, ext_band;
const int min_band_count = s->samplerate_idx > 7 ? 1 : 3;
b->band_count = get_bits(gb, 4) + min_band_count;
b->q_unit_cnt = at9_tab_band_q_unit_map[b->band_count];
b->band_ext_q_unit = b->stereo_q_unit = b->q_unit_cnt;
if (b->band_count > at9_tab_sri_max_bands[s->samplerate_idx]) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid band count %i!\n",
b->band_count);
return AVERROR_INVALIDDATA;
}
if (stereo) {
stereo_band = get_bits(gb, 4) + min_band_count;
if (stereo_band > b->band_count) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid stereo band %i!\n",
stereo_band);
return AVERROR_INVALIDDATA;
}
b->stereo_q_unit = at9_tab_band_q_unit_map[stereo_band];
}
b->has_band_ext = get_bits1(gb);
if (b->has_band_ext) {
ext_band = get_bits(gb, 4) + min_band_count;
if (ext_band < b->band_count) {
av_log(s->avctx, AV_LOG_ERROR, "Invalid extension band %i!\n",
ext_band);
return AVERROR_INVALIDDATA;
}
b->band_ext_q_unit = at9_tab_band_q_unit_map[ext_band];
}
}
/* Calculate bit alloc gradient */
if (parse_gradient(s, b, gb))
return AVERROR_INVALIDDATA;
/* IS data */
b->cpe_base_channel = 0;
if (stereo) {
b->cpe_base_channel = get_bits1(gb);
if (get_bits1(gb)) {
for (int i = b->stereo_q_unit; i < b->q_unit_cnt; i++)
b->is_signs[i] = 1 - 2*get_bits1(gb);
} else {
for (int i = 0; i < FF_ARRAY_ELEMS(b->is_signs); i++)
b->is_signs[i] = 1;
}
}
/* Band extension */
if (parse_band_ext(s, b, gb, stereo))
return AVERROR_INVALIDDATA;
/* Scalefactors */
for (int i = 0; i <= stereo; i++) {
ATRAC9ChannelData *c = &b->channel[i];
c->q_unit_cnt = i == b->cpe_base_channel ? b->q_unit_cnt :
b->stereo_q_unit;
if (read_scalefactors(s, b, c, gb, i, first_in_pkt))
return AVERROR_INVALIDDATA;
calc_precision (s, b, c);
calc_codebook_idx (s, b, c);
read_coeffs_coarse(s, b, c, gb);
read_coeffs_fine (s, b, c, gb);
dequantize (s, b, c);
}
b->q_unit_cnt_prev = b->has_band_ext ? b->band_ext_q_unit : b->q_unit_cnt;
apply_intensity_stereo(s, b, stereo);
apply_scalefactors (s, b, stereo);
apply_band_extension (s, b, stereo);
imdct:
for (int i = 0; i <= stereo; i++) {
ATRAC9ChannelData *c = &b->channel[i];
const int dst_idx = s->block_config->plane_map[block_idx][i];
const int wsize = 1 << s->frame_log2;
const ptrdiff_t offset = wsize*frame_idx*sizeof(float);
float *dst = (float *)(frame->extended_data[dst_idx] + offset);
s->imdct.imdct_half(&s->imdct, s->temp, c->coeffs);
s->fdsp->vector_fmul_window(dst, c->prev_win, s->temp,
s->imdct_win, wsize >> 1);
memcpy(c->prev_win, s->temp + (wsize >> 1), sizeof(float)*wsize >> 1);
}
return 0;
}
static int atrac9_decode_frame(AVCodecContext *avctx, void *data,
int *got_frame_ptr, AVPacket *avpkt)
{
int ret;
GetBitContext gb;
AVFrame *frame = data;
ATRAC9Context *s = avctx->priv_data;
const int frames = FFMIN(avpkt->size / s->avg_frame_size, s->frame_count);
frame->nb_samples = (1 << s->frame_log2) * frames;
ret = ff_get_buffer(avctx, frame, 0);
if (ret < 0)
return ret;
init_get_bits8(&gb, avpkt->data, avpkt->size);
for (int i = 0; i < frames; i++) {
for (int j = 0; j < s->block_config->count; j++) {
ret = atrac9_decode_block(s, &gb, &s->block[j], frame, i, j);
if (ret)
return ret;
align_get_bits(&gb);
}
}
*got_frame_ptr = 1;
return avctx->block_align;
}
static void atrac9_decode_flush(AVCodecContext *avctx)
{
ATRAC9Context *s = avctx->priv_data;
for (int j = 0; j < s->block_config->count; j++) {
ATRAC9BlockData *b = &s->block[j];
const int stereo = s->block_config->type[j] == ATRAC9_BLOCK_TYPE_CPE;
for (int i = 0; i <= stereo; i++) {
ATRAC9ChannelData *c = &b->channel[i];
memset(c->prev_win, 0, sizeof(c->prev_win));
}
}
}
static av_cold int atrac9_decode_close(AVCodecContext *avctx)
{
ATRAC9Context *s = avctx->priv_data;
for (int i = 1; i < 7; i++)
ff_free_vlc(&s->sf_vlc[0][i]);
for (int i = 2; i < 6; i++)
ff_free_vlc(&s->sf_vlc[1][i]);
for (int i = 0; i < 2; i++)
for (int j = 0; j < 8; j++)
for (int k = 0; k < 4; k++)
ff_free_vlc(&s->coeff_vlc[i][j][k]);
ff_mdct_end(&s->imdct);
av_free(s->fdsp);
return 0;
}
static av_cold int atrac9_decode_init(AVCodecContext *avctx)
{
GetBitContext gb;
ATRAC9Context *s = avctx->priv_data;
int version, block_config_idx, superframe_idx, alloc_c_len;
s->avctx = avctx;
av_lfg_init(&s->lfg, 0xFBADF00D);
if (avctx->extradata_size != 12) {
av_log(avctx, AV_LOG_ERROR, "Invalid extradata length!\n");
return AVERROR_INVALIDDATA;
}
version = AV_RL32(avctx->extradata);
if (version > 2) {
av_log(avctx, AV_LOG_ERROR, "Unsupported version (%i)!\n", version);
return AVERROR_INVALIDDATA;
}
init_get_bits8(&gb, avctx->extradata + 4, avctx->extradata_size);
if (get_bits(&gb, 8) != 0xFE) {
av_log(avctx, AV_LOG_ERROR, "Incorrect magic byte!\n");
return AVERROR_INVALIDDATA;
}
s->samplerate_idx = get_bits(&gb, 4);
avctx->sample_rate = at9_tab_samplerates[s->samplerate_idx];
block_config_idx = get_bits(&gb, 3);
if (block_config_idx > 5) {
av_log(avctx, AV_LOG_ERROR, "Incorrect block config!\n");
return AVERROR_INVALIDDATA;
}
s->block_config = &at9_block_layout[block_config_idx];
avctx->channel_layout = s->block_config->channel_layout;
avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
if (get_bits1(&gb)) {
av_log(avctx, AV_LOG_ERROR, "Incorrect verification bit!\n");
return AVERROR_INVALIDDATA;
}
/* Average frame size in bytes */
s->avg_frame_size = get_bits(&gb, 11) + 1;
superframe_idx = get_bits(&gb, 2);
if (superframe_idx & 1) {
av_log(avctx, AV_LOG_ERROR, "Invalid superframe index!\n");
return AVERROR_INVALIDDATA;
}
s->frame_count = 1 << superframe_idx;
s->frame_log2 = at9_tab_sri_frame_log2[s->samplerate_idx];
if (ff_mdct_init(&s->imdct, s->frame_log2 + 1, 1, 1.0f / 32768.0f))
return AVERROR(ENOMEM);
s->fdsp = avpriv_float_dsp_alloc(avctx->flags & AV_CODEC_FLAG_BITEXACT);
if (!s->fdsp)
return AVERROR(ENOMEM);
/* iMDCT window */
for (int i = 0; i < (1 << s->frame_log2); i++) {
const int len = 1 << s->frame_log2;
const float sidx = ( i + 0.5f) / len;
const float eidx = (len - i - 0.5f) / len;
const float s_c = sinf(sidx*M_PI - M_PI_2)*0.5f + 0.5f;
const float e_c = sinf(eidx*M_PI - M_PI_2)*0.5f + 0.5f;
s->imdct_win[i] = s_c / ((s_c * s_c) + (e_c * e_c));
}
/* Allocation curve */
alloc_c_len = FF_ARRAY_ELEMS(at9_tab_b_dist);
for (int i = 1; i <= alloc_c_len; i++)
for (int j = 0; j < i; j++)
s->alloc_curve[i - 1][j] = at9_tab_b_dist[(j * alloc_c_len) / i];
/* Unsigned scalefactor VLCs */
for (int i = 1; i < 7; i++) {
const HuffmanCodebook *hf = &at9_huffman_sf_unsigned[i];
init_vlc(&s->sf_vlc[0][i], 9, hf->size, hf->bits, 1, 1, hf->codes,
2, 2, 0);
}
/* Signed scalefactor VLCs */
for (int i = 2; i < 6; i++) {
const HuffmanCodebook *hf = &at9_huffman_sf_signed[i];
int nums = hf->size;
int16_t sym[32];
for (int j = 0; j < nums; j++)
sym[j] = sign_extend(j, hf->value_bits);
ff_init_vlc_sparse(&s->sf_vlc[1][i], 9, hf->size, hf->bits, 1, 1,
hf->codes, 2, 2, sym, sizeof(*sym), sizeof(*sym), 0);
}
/* Coefficient VLCs */
for (int i = 0; i < 2; i++) {
for (int j = 0; j < 8; j++) {
for (int k = 0; k < 4; k++) {
const HuffmanCodebook *hf = &at9_huffman_coeffs[i][j][k];
init_vlc(&s->coeff_vlc[i][j][k], 9, hf->size, hf->bits, 1, 1,
hf->codes, 2, 2, 0);
}
}
}
return 0;
}
AVCodec ff_atrac9_decoder = {
.name = "atrac9",
.long_name = NULL_IF_CONFIG_SMALL("ATRAC9 (Adaptive TRansform Acoustic Coding 9)"),
.type = AVMEDIA_TYPE_AUDIO,
.id = AV_CODEC_ID_ATRAC9,
.priv_data_size = sizeof(ATRAC9Context),
.init = atrac9_decode_init,
.close = atrac9_decode_close,
.decode = atrac9_decode_frame,
.flush = atrac9_decode_flush,
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
.capabilities = AV_CODEC_CAP_SUBFRAMES | AV_CODEC_CAP_DR1,
};