FFmpeg/libavcodec/aacps_common.c
Andreas Rheinhardt 4f1ae39036 avcodec/aacps_common: Use minimal VLC nb_bits/max_depth
Reviewed-by: Lynne <dev@lynne.ee>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
2020-12-31 23:18:55 +01:00

337 lines
11 KiB
C

/*
* Functions common to fixed/float MPEG-4 Parametric Stereo decoding
* Copyright (c) 2010 Alex Converse <alex.converse@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 <stdint.h>
#include "libavutil/common.h"
#include "libavutil/thread.h"
#include "aacps.h"
#include "get_bits.h"
#include "aacpsdata.c"
static const int8_t num_env_tab[2][4] = {
{ 0, 1, 2, 4, },
{ 1, 2, 3, 4, },
};
static const int8_t nr_iidicc_par_tab[] = {
10, 20, 34, 10, 20, 34,
};
static const int8_t nr_iidopd_par_tab[] = {
5, 11, 17, 5, 11, 17,
};
enum {
huff_iid_df1,
huff_iid_dt1,
huff_iid_df0,
huff_iid_dt0,
huff_icc_df,
huff_icc_dt,
huff_ipd_df,
huff_ipd_dt,
huff_opd_df,
huff_opd_dt,
};
static const int huff_iid[] = {
huff_iid_df0,
huff_iid_df1,
huff_iid_dt0,
huff_iid_dt1,
};
static VLC vlc_ps[10];
#define READ_PAR_DATA(PAR, OFFSET, MASK, ERR_CONDITION, NB_BITS, MAX_DEPTH) \
/** \
* Read Inter-channel Intensity Difference/Inter-Channel Coherence/ \
* Inter-channel Phase Difference/Overall Phase Difference parameters from the \
* bitstream. \
* \
* @param avctx contains the current codec context \
* @param gb pointer to the input bitstream \
* @param ps pointer to the Parametric Stereo context \
* @param PAR pointer to the parameter to be read \
* @param e envelope to decode \
* @param dt 1: time delta-coded, 0: frequency delta-coded \
*/ \
static int read_ ## PAR ## _data(AVCodecContext *avctx, GetBitContext *gb, PSCommonContext *ps, \
int8_t (*PAR)[PS_MAX_NR_IIDICC], int table_idx, int e, int dt) \
{ \
int b, num = ps->nr_ ## PAR ## _par; \
VLC_TYPE (*vlc_table)[2] = vlc_ps[table_idx].table; \
if (dt) { \
int e_prev = e ? e - 1 : ps->num_env_old - 1; \
e_prev = FFMAX(e_prev, 0); \
for (b = 0; b < num; b++) { \
int val = PAR[e_prev][b] + get_vlc2(gb, vlc_table, NB_BITS, MAX_DEPTH) - OFFSET; \
if (MASK) val &= MASK; \
PAR[e][b] = val; \
if (ERR_CONDITION) \
goto err; \
} \
} else { \
int val = 0; \
for (b = 0; b < num; b++) { \
val += get_vlc2(gb, vlc_table, NB_BITS, MAX_DEPTH) - OFFSET; \
if (MASK) val &= MASK; \
PAR[e][b] = val; \
if (ERR_CONDITION) \
goto err; \
} \
} \
return 0; \
err: \
av_log(avctx, AV_LOG_ERROR, "illegal "#PAR"\n"); \
return AVERROR_INVALIDDATA; \
}
READ_PAR_DATA(iid, huff_offset[table_idx], 0, FFABS(ps->iid_par[e][b]) > 7 + 8 * ps->iid_quant, 9, 3)
READ_PAR_DATA(icc, huff_offset[table_idx], 0, ps->icc_par[e][b] > 7U, 9, 2)
READ_PAR_DATA(ipdopd, 0, 0x07, 0, 5, 1)
static int ps_read_extension_data(GetBitContext *gb, PSCommonContext *ps,
int ps_extension_id)
{
int e;
int count = get_bits_count(gb);
if (ps_extension_id)
return 0;
ps->enable_ipdopd = get_bits1(gb);
if (ps->enable_ipdopd) {
for (e = 0; e < ps->num_env; e++) {
int dt = get_bits1(gb);
read_ipdopd_data(NULL, gb, ps, ps->ipd_par, dt ? huff_ipd_dt : huff_ipd_df, e, dt);
dt = get_bits1(gb);
read_ipdopd_data(NULL, gb, ps, ps->opd_par, dt ? huff_opd_dt : huff_opd_df, e, dt);
}
}
skip_bits1(gb); //reserved_ps
return get_bits_count(gb) - count;
}
int ff_ps_read_data(AVCodecContext *avctx, GetBitContext *gb_host,
PSCommonContext *ps, int bits_left)
{
int e;
int bit_count_start = get_bits_count(gb_host);
int header;
int bits_consumed;
GetBitContext gbc = *gb_host, *gb = &gbc;
header = get_bits1(gb);
if (header) { //enable_ps_header
ps->enable_iid = get_bits1(gb);
if (ps->enable_iid) {
int iid_mode = get_bits(gb, 3);
if (iid_mode > 5) {
av_log(avctx, AV_LOG_ERROR, "iid_mode %d is reserved.\n",
iid_mode);
goto err;
}
ps->nr_iid_par = nr_iidicc_par_tab[iid_mode];
ps->iid_quant = iid_mode > 2;
ps->nr_ipdopd_par = nr_iidopd_par_tab[iid_mode];
}
ps->enable_icc = get_bits1(gb);
if (ps->enable_icc) {
ps->icc_mode = get_bits(gb, 3);
if (ps->icc_mode > 5) {
av_log(avctx, AV_LOG_ERROR, "icc_mode %d is reserved.\n",
ps->icc_mode);
goto err;
}
ps->nr_icc_par = nr_iidicc_par_tab[ps->icc_mode];
}
ps->enable_ext = get_bits1(gb);
}
ps->frame_class = get_bits1(gb);
ps->num_env_old = ps->num_env;
ps->num_env = num_env_tab[ps->frame_class][get_bits(gb, 2)];
ps->border_position[0] = -1;
if (ps->frame_class) {
for (e = 1; e <= ps->num_env; e++) {
ps->border_position[e] = get_bits(gb, 5);
if (ps->border_position[e] < ps->border_position[e-1]) {
av_log(avctx, AV_LOG_ERROR, "border_position non monotone.\n");
goto err;
}
}
} else
for (e = 1; e <= ps->num_env; e++)
ps->border_position[e] = (e * numQMFSlots >> ff_log2_tab[ps->num_env]) - 1;
if (ps->enable_iid) {
for (e = 0; e < ps->num_env; e++) {
int dt = get_bits1(gb);
if (read_iid_data(avctx, gb, ps, ps->iid_par, huff_iid[2*dt+ps->iid_quant], e, dt))
goto err;
}
} else
memset(ps->iid_par, 0, sizeof(ps->iid_par));
if (ps->enable_icc)
for (e = 0; e < ps->num_env; e++) {
int dt = get_bits1(gb);
if (read_icc_data(avctx, gb, ps, ps->icc_par, dt ? huff_icc_dt : huff_icc_df, e, dt))
goto err;
}
else
memset(ps->icc_par, 0, sizeof(ps->icc_par));
if (ps->enable_ext) {
int cnt = get_bits(gb, 4);
if (cnt == 15) {
cnt += get_bits(gb, 8);
}
cnt *= 8;
while (cnt > 7) {
int ps_extension_id = get_bits(gb, 2);
cnt -= 2 + ps_read_extension_data(gb, ps, ps_extension_id);
}
if (cnt < 0) {
av_log(avctx, AV_LOG_ERROR, "ps extension overflow %d\n", cnt);
goto err;
}
skip_bits(gb, cnt);
}
ps->enable_ipdopd &= !PS_BASELINE;
//Fix up envelopes
if (!ps->num_env || ps->border_position[ps->num_env] < numQMFSlots - 1) {
//Create a fake envelope
int source = ps->num_env ? ps->num_env - 1 : ps->num_env_old - 1;
int b;
if (source >= 0 && source != ps->num_env) {
if (ps->enable_iid) {
memcpy(ps->iid_par+ps->num_env, ps->iid_par+source, sizeof(ps->iid_par[0]));
}
if (ps->enable_icc) {
memcpy(ps->icc_par+ps->num_env, ps->icc_par+source, sizeof(ps->icc_par[0]));
}
if (ps->enable_ipdopd) {
memcpy(ps->ipd_par+ps->num_env, ps->ipd_par+source, sizeof(ps->ipd_par[0]));
memcpy(ps->opd_par+ps->num_env, ps->opd_par+source, sizeof(ps->opd_par[0]));
}
}
if (ps->enable_iid){
for (b = 0; b < ps->nr_iid_par; b++) {
if (FFABS(ps->iid_par[ps->num_env][b]) > 7 + 8 * ps->iid_quant) {
av_log(avctx, AV_LOG_ERROR, "iid_par invalid\n");
goto err;
}
}
}
if (ps->enable_icc){
for (b = 0; b < ps->nr_iid_par; b++) {
if (ps->icc_par[ps->num_env][b] > 7U) {
av_log(avctx, AV_LOG_ERROR, "icc_par invalid\n");
goto err;
}
}
}
ps->num_env++;
ps->border_position[ps->num_env] = numQMFSlots - 1;
}
ps->is34bands_old = ps->is34bands;
if (!PS_BASELINE && (ps->enable_iid || ps->enable_icc))
ps->is34bands = (ps->enable_iid && ps->nr_iid_par == 34) ||
(ps->enable_icc && ps->nr_icc_par == 34);
//Baseline
if (!ps->enable_ipdopd) {
memset(ps->ipd_par, 0, sizeof(ps->ipd_par));
memset(ps->opd_par, 0, sizeof(ps->opd_par));
}
if (header)
ps->start = 1;
bits_consumed = get_bits_count(gb) - bit_count_start;
if (bits_consumed <= bits_left) {
skip_bits_long(gb_host, bits_consumed);
return bits_consumed;
}
av_log(avctx, AV_LOG_ERROR, "Expected to read %d PS bits actually read %d.\n", bits_left, bits_consumed);
err:
ps->start = 0;
skip_bits_long(gb_host, bits_left);
memset(ps->iid_par, 0, sizeof(ps->iid_par));
memset(ps->icc_par, 0, sizeof(ps->icc_par));
memset(ps->ipd_par, 0, sizeof(ps->ipd_par));
memset(ps->opd_par, 0, sizeof(ps->opd_par));
return bits_left;
}
#define PS_INIT_VLC_STATIC(num, nb_bits, size) \
INIT_VLC_STATIC(&vlc_ps[num], nb_bits, ps_tmp[num].table_size / ps_tmp[num].elem_size, \
ps_tmp[num].ps_bits, 1, 1, \
ps_tmp[num].ps_codes, ps_tmp[num].elem_size, ps_tmp[num].elem_size, \
size);
#define PS_VLC_ROW(name) \
{ name ## _codes, name ## _bits, sizeof(name ## _codes), sizeof(name ## _codes[0]) }
static av_cold void ps_init_common(void)
{
// Syntax initialization
static const struct {
const void *ps_codes, *ps_bits;
const unsigned int table_size, elem_size;
} ps_tmp[] = {
PS_VLC_ROW(huff_iid_df1),
PS_VLC_ROW(huff_iid_dt1),
PS_VLC_ROW(huff_iid_df0),
PS_VLC_ROW(huff_iid_dt0),
PS_VLC_ROW(huff_icc_df),
PS_VLC_ROW(huff_icc_dt),
PS_VLC_ROW(huff_ipd_df),
PS_VLC_ROW(huff_ipd_dt),
PS_VLC_ROW(huff_opd_df),
PS_VLC_ROW(huff_opd_dt),
};
PS_INIT_VLC_STATIC(0, 9, 1544);
PS_INIT_VLC_STATIC(1, 9, 832);
PS_INIT_VLC_STATIC(2, 9, 1024);
PS_INIT_VLC_STATIC(3, 9, 1036);
PS_INIT_VLC_STATIC(4, 9, 544);
PS_INIT_VLC_STATIC(5, 9, 544);
PS_INIT_VLC_STATIC(6, 5, 32);
PS_INIT_VLC_STATIC(7, 5, 32);
PS_INIT_VLC_STATIC(8, 5, 32);
PS_INIT_VLC_STATIC(9, 5, 32);
}
av_cold void ff_ps_init_common(void)
{
static AVOnce init_static_once = AV_ONCE_INIT;
ff_thread_once(&init_static_once, ps_init_common);
}