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| author | Andreas Rheinhardt <andreas.rheinhardt@outlook.com> | 2022-09-12 22:24:04 +0200 |
|---|---|---|
| committer | Andreas Rheinhardt <andreas.rheinhardt@outlook.com> | 2022-09-16 18:07:29 +0200 |
| commit | 62d9b1195a039f88f8f82d2a519bf88c75f3cdbd (patch) | |
| tree | 5863b314fb8e0a9536e28f38f2a4f0348874967b | |
| parent | 465e27e0f2b35b13d348c882c723158a36a802ef (diff) | |
| download | ffmpeg-62d9b1195a039f88f8f82d2a519bf88c75f3cdbd.tar.gz | |
avcodec/dca_lbr: Hardcode lpc table to save space
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>
| -rw-r--r-- | libavcodec/dca_lbr.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/libavcodec/dca_lbr.c b/libavcodec/dca_lbr.c index 579bd9c469..9a0eb62f06 100644 --- a/libavcodec/dca_lbr.c +++ b/libavcodec/dca_lbr.c @@ -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) |