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avcodec/dca_lbr: Hardcode lpc table to save space

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The code to initialize it takes more space (in .text) than
the table to be initialized (namely 86B vs 64B for GCC 11.2
with -O3 in an av_cold function), so hardcode the table.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This commit is contained in:
Andreas Rheinhardt 2022-09-12 22:24:04 +02:00
parent 465e27e0f2
commit 62d9b1195a
1 changed files with 11 additions and 4 deletions
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15
libavcodec/dca_lbr.c
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@ -119,7 +119,17 @@ static const uint16_t channel_layouts[7] = {
};
static float cos_tab[256];
static float lpc_tab[16];
static const float lpc_tab[16] = {
/* lpc_tab[i] = sin((i - 8) * (M_PI / ((i < 8) ? 17 : 15))) */
-0.995734176295034521871191178905, -0.961825643172819070408796290732,
-0.895163291355062322067016499754, -0.798017227280239503332805112796,
-0.673695643646557211712691912426, -0.526432162877355800244607799141,
-0.361241666187152948744714596184, -0.183749517816570331574408839621,
0.0, 0.207911690817759337101742284405,
0.406736643075800207753985990341, 0.587785252292473129168705954639,
0.743144825477394235014697048974, 0.866025403784438646763723170753,
0.951056516295153572116439333379, 0.994521895368273336922691944981
};
av_cold void ff_dca_lbr_init_tables(void)
{
@ -127,9 +137,6 @@ av_cold void ff_dca_lbr_init_tables(void)
for (i = 0; i < 256; i++)
cos_tab[i] = cos(M_PI * i / 128);
for (i = 0; i < 16; i++)
lpc_tab[i] = sin((i - 8) * (M_PI / ((i < 8) ? 17 : 15)));
}
static int parse_lfe_24(DCALbrDecoder *s)