Skip to content

F
ffmpeg.wasm-core
Commit 1076b0d0 authored by Alex Converse's avatar Alex Converse
Browse files
Options

psdec: Factorize iid/icc/ipd/opd parameter bitstream reading. 

Originally committed as revision 23652 to svn://svn.ffmpeg.org/ffmpeg/trunk
parent 10ed37b5
Hide whitespace changes
Inline Side-by-side
Showing with 41 additions and 128 deletions
libavcodec/ps.c
View file @ 1076b0d0
......@@ -67,139 +67,52 @@ static const int huff_iid[] = {
static VLC vlc_ps[10];
/**
* Read Inter-channel Intensity Difference parameters from the bitstream.
* 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 iid_data(AVCodecContext *avctx, GetBitContext *gb, PSContext *ps, int e, int dt)
{
int b;
int table_idx = huff_iid[2*dt+ps->iid_quant];
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 < ps->nr_iid_par; b++) {
ps->iid_par[e][b] = ps->iid_par[e_prev][b] +
get_vlc2(gb, vlc_table, 9, 3) -
huff_offset[table_idx];
if (FFABS(ps->iid_par[e][b]) > 7 + 8 * ps->iid_quant)
goto err;
}
} else {
int prev = 0;
for (b = 0; b < ps->nr_iid_par; b++) {
prev += get_vlc2(gb, vlc_table, 9, 3) -
huff_offset[table_idx];
ps->iid_par[e][b] = prev;
if (FFABS(ps->iid_par[e][b]) > 7 + 8 * ps->iid_quant)
goto err;
}
}
return 0;
err:
av_log(avctx, AV_LOG_ERROR, "illegal iid\n");
return -1;
}
/**
* Read Inter-Channel Coherence 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 e envelope to decode
* @param dt 1: time delta-coded, 0: frequency delta-coded
*/
static int icc_data(AVCodecContext *avctx, GetBitContext *gb, PSContext *ps, int e, int dt)
{
int b;
int table_idx = dt ? huff_icc_dt : huff_icc_df;
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 < ps->nr_icc_par; b++) {
ps->icc_par[e][b] = ps->icc_par[e_prev][b] + get_vlc2(gb, vlc_table, 9, 3) - huff_offset[table_idx];
if (ps->icc_par[e][b] > 7U)
goto err;
}
} else {
int prev = 0;
for (b = 0; b < ps->nr_icc_par; b++) {
prev += get_vlc2(gb, vlc_table, 9, 3) - huff_offset[table_idx];
ps->icc_par[e][b] = prev;
if (ps->icc_par[e][b] > 7U)
goto err;
}
}
return 0;
err:
av_log(avctx, AV_LOG_ERROR, "illegal icc\n");
return -1;
#define READ_PAR_DATA(PAR, OFFSET, MASK, ERR_CONDITION) \
static int PAR ## _data(AVCodecContext *avctx, GetBitContext *gb, PSContext *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, 9, 3) - 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, 9, 3) - 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 -1; \
}
/**
* Read Inter-channel Phase Difference parameters from the bitstream.
*
* @param gb pointer to the input bitstream
* @param ps pointer to the Parametric Stereo context
* @param e envelope to decode
* @param dt 1: time delta-coded, 0: frequency delta-coded
*/
static void ipd_data(GetBitContext *gb, PSContext *ps, int e, int dt)
{
int b;
int table_idx = dt ? huff_ipd_dt : huff_ipd_df;
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 < ps->nr_ipdopd_par; b++) {
ps->ipd_par[e][b] = (ps->ipd_par[e_prev][b] + get_vlc2(gb, vlc_table, 9, 1)) & 0x07;
}
} else {
int prev = 0;
for (b = 0; b < ps->nr_ipdopd_par; b++) {
prev += get_vlc2(gb, vlc_table, 9, 3);
prev &= 0x07;
ps->ipd_par[e][b] = prev;
}
}
}
/**
* Read Overall Phase Difference parameters from the bitstream.
*
* @param gb pointer to the input bitstream
* @param ps pointer to the Parametric Stereo context
* @param e envelope to decode
* @param dt 1: time delta-coded, 0: frequency delta-coded
*/
static void opd_data(GetBitContext *gb, PSContext *ps, int e, int dt)
{
int b;
int table_idx = dt ? huff_opd_dt : huff_opd_df;
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 < ps->nr_ipdopd_par; b++) {
ps->opd_par[e][b] = (ps->opd_par[e_prev][b] + get_vlc2(gb, vlc_table, 9, 1)) & 0x07;
}
} else {
int prev = 0;
for (b = 0; b < ps->nr_ipdopd_par; b++) {
prev += get_vlc2(gb, vlc_table, 9, 3);
prev &= 0x07;
ps->opd_par[e][b] = prev;
}
}
}
READ_PAR_DATA(iid, huff_offset[table_idx], 0, FFABS(ps->iid_par[e][b]) > 7 + 8 * ps->iid_quant)
READ_PAR_DATA(icc, huff_offset[table_idx], 0, ps->icc_par[e][b] > 7U)
READ_PAR_DATA(ipdopd, 0, 0x07, 0)
static int ps_extension(GetBitContext *gb, PSContext *ps, int ps_extension_id)
{
......@@ -213,9 +126,9 @@ static int ps_extension(GetBitContext *gb, PSContext *ps, int ps_extension_id)
if (ps->enable_ipdopd) {
for (e = 0; e < ps->num_env; e++) {
int dt = get_bits1(gb);
ipd_data(gb, ps, e, dt);
ipdopd_data(NULL, gb, ps, ps->ipd_par, dt ? huff_ipd_dt : huff_ipd_df, e, dt);
dt = get_bits1(gb);
opd_data(gb, ps, e, dt);
ipdopd_data(NULL, gb, ps, ps->opd_par, dt ? huff_opd_dt : huff_opd_df, e, dt);
}
}
skip_bits1(gb); //reserved_ps
......@@ -281,7 +194,7 @@ int ff_ps_read_data(AVCodecContext *avctx, GetBitContext *gb_host, PSContext *ps
if (ps->enable_iid) {
for (e = 0; e < ps->num_env; e++) {
int dt = get_bits1(gb);
if (iid_data(avctx, gb, ps, e, dt))
if (iid_data(avctx, gb, ps, ps->iid_par, huff_iid[2*dt+ps->iid_quant], e, dt))
goto err;
}
} else
......@@ -290,7 +203,7 @@ int ff_ps_read_data(AVCodecContext *avctx, GetBitContext *gb_host, PSContext *ps
if (ps->enable_icc)
for (e = 0; e < ps->num_env; e++) {
int dt = get_bits1(gb);
if (icc_data(avctx, gb, ps, e, dt))
if (icc_data(avctx, gb, ps, ps->icc_par, dt ? huff_icc_dt : huff_icc_df, e, dt))
goto err;
}
else
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment