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avcodec/mpegaudiodsp: Combine initializing float and int tables

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This avoids code duplication in the functions used to initialize them
and allows to remove an AVOnce.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
This commit is contained in:
Andreas Rheinhardt 2020-11-15 15:53:34 +01:00
parent af7acbb4b8
commit 5c45f7e156
3 changed files with 50 additions and 49 deletions
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54
libavcodec/mpegaudiodsp.c
View File

@ -21,20 +21,66 @@
#include "config.h"
#include "libavutil/attributes.h"
#include "libavutil/thread.h"
#include "mpegaudio.h"
#include "mpegaudiodsp.h"
#include "dct.h"
#include "dct32.h"
static AVOnce mpadsp_float_table_init = AV_ONCE_INIT;
static AVOnce mpadsp_fixed_table_init = AV_ONCE_INIT;
static AVOnce mpadsp_table_init = AV_ONCE_INIT;
static av_cold void mpadsp_init_tabs(void)
{
int i, j;
/* compute mdct windows */
for (i = 0; i < 36; i++) {
for (j = 0; j < 4; j++) {
double d;
if (j == 2 && i % 3 != 1)
continue;
d = sin(M_PI * (i + 0.5) / 36.0);
if (j == 1) {
if (i >= 30) d = 0;
else if (i >= 24) d = sin(M_PI * (i - 18 + 0.5) / 12.0);
else if (i >= 18) d = 1;
} else if (j == 3) {
if (i < 6) d = 0;
else if (i < 12) d = sin(M_PI * (i - 6 + 0.5) / 12.0);
else if (i < 18) d = 1;
}
//merge last stage of imdct into the window coefficients
d *= 0.5 * IMDCT_SCALAR / cos(M_PI * (2 * i + 19) / 72);
if (j == 2) {
ff_mdct_win_float[j][i/3] = d / (1 << 5);
ff_mdct_win_fixed[j][i/3] = d / (1 << 5) * (1LL << 32) + 0.5;
} else {
int idx = i < 18 ? i : i + (MDCT_BUF_SIZE/2 - 18);
ff_mdct_win_float[j][idx] = d / (1 << 5);
ff_mdct_win_fixed[j][idx] = d / (1 << 5) * (1LL << 32) + 0.5;
}
}
}
/* NOTE: we do frequency inversion after the MDCT by changing
the sign of the right window coefs */
for (j = 0; j < 4; j++) {
for (i = 0; i < MDCT_BUF_SIZE; i += 2) {
ff_mdct_win_float[j + 4][i ] = ff_mdct_win_float[j][i ];
ff_mdct_win_float[j + 4][i + 1] = -ff_mdct_win_float[j][i + 1];
ff_mdct_win_fixed[j + 4][i ] = ff_mdct_win_fixed[j][i ];
ff_mdct_win_fixed[j + 4][i + 1] = -ff_mdct_win_fixed[j][i + 1];
}
}
}
av_cold void ff_mpadsp_init(MPADSPContext *s)
{
DCTContext dct;
ff_dct_init(&dct, 5, DCT_II);
ff_thread_once(&mpadsp_float_table_init, &ff_init_mpadsp_tabs_float);
ff_thread_once(&mpadsp_fixed_table_init, &ff_init_mpadsp_tabs_fixed);
ff_thread_once(&mpadsp_table_init, &mpadsp_init_tabs);
s->apply_window_float = ff_mpadsp_apply_window_float;
s->apply_window_fixed = ff_mpadsp_apply_window_fixed;

3
libavcodec/mpegaudiodsp.h
View File

@ -82,9 +82,6 @@ void ff_imdct36_blocks_float(float *out, float *buf, float *in,
void ff_imdct36_blocks_fixed(int *out, int *buf, int *in,
int count, int switch_point, int block_type);
void ff_init_mpadsp_tabs_float(void);
void ff_init_mpadsp_tabs_fixed(void);
/** For SSE implementation, MDCT_BUF_SIZE/2 should be 128-bit aligned */
#define MDCT_BUF_SIZE FFALIGN(36, 2*4)

42
libavcodec/mpegaudiodsp_template.c
View File

@ -221,48 +221,6 @@ av_cold void RENAME(ff_mpa_synth_init)(MPA_INT *window)
window[512+128+16*i+j] = window[64*i+48-j];
}
av_cold void RENAME(ff_init_mpadsp_tabs)(void)
{
int i, j;
/* compute mdct windows */
for (i = 0; i < 36; i++) {
for (j = 0; j < 4; j++) {
double d;
if (j == 2 && i % 3 != 1)
continue;
d = sin(M_PI * (i + 0.5) / 36.0);
if (j == 1) {
if (i >= 30) d = 0;
else if (i >= 24) d = sin(M_PI * (i - 18 + 0.5) / 12.0);
else if (i >= 18) d = 1;
} else if (j == 3) {
if (i < 6) d = 0;
else if (i < 12) d = sin(M_PI * (i - 6 + 0.5) / 12.0);
else if (i < 18) d = 1;
}
//merge last stage of imdct into the window coefficients
d *= 0.5 * IMDCT_SCALAR / cos(M_PI * (2 * i + 19) / 72);
if (j == 2)
RENAME(ff_mdct_win)[j][i/3] = FIXHR((d / (1<<5)));
else {
int idx = i < 18 ? i : i + (MDCT_BUF_SIZE/2 - 18);
RENAME(ff_mdct_win)[j][idx] = FIXHR((d / (1<<5)));
}
}
}
/* NOTE: we do frequency inversion adter the MDCT by changing
the sign of the right window coefs */
for (j = 0; j < 4; j++) {
for (i = 0; i < MDCT_BUF_SIZE; i += 2) {
RENAME(ff_mdct_win)[j + 4][i ] = RENAME(ff_mdct_win)[j][i ];
RENAME(ff_mdct_win)[j + 4][i + 1] = -RENAME(ff_mdct_win)[j][i + 1];
}
}
}
/* cos(pi*i/18) */
#define C1 FIXHR(0.98480775301220805936/2)
#define C2 FIXHR(0.93969262078590838405/2)