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avcodec/aacdec_template: Use VLC symbols table

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Expressions like array[get_vlc2()] can be optimized by using a symbols
table if the array is always the same for a given VLC. This requirement
is fulfilled for several VLCs used by the AAC decoders.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
pull/358/head
Andreas Rheinhardt 4 years ago
parent 097277f31a
commit d9e6e9360d
1 changed files with 13 additions and 12 deletions
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  1. 25
      libavcodec/aacdec_template.c

25
libavcodec/aacdec_template.c
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@ -1204,11 +1204,13 @@ static av_cold void aac_static_table_init(void)
for (unsigned i = 0, offset = 0; i < 11; i++) {
vlc_spectral[i].table = &vlc_buf[offset];
vlc_spectral[i].table_allocated = FF_ARRAY_ELEMS(vlc_buf) - offset;
init_vlc(&vlc_spectral[i], 8, ff_aac_spectral_sizes[i],
ff_aac_spectral_bits[i], sizeof(ff_aac_spectral_bits[i][0]),
sizeof(ff_aac_spectral_bits[i][0]),
ff_aac_spectral_codes[i], sizeof(ff_aac_spectral_codes[i][0]),
sizeof(ff_aac_spectral_codes[i][0]),
ff_init_vlc_sparse(&vlc_spectral[i], 8, ff_aac_spectral_sizes[i],
ff_aac_spectral_bits[i], sizeof(ff_aac_spectral_bits[i][0]),
sizeof(ff_aac_spectral_bits[i][0]),
ff_aac_spectral_codes[i], sizeof(ff_aac_spectral_codes[i][0]),
sizeof(ff_aac_spectral_codes[i][0]),
ff_aac_codebook_vector_idx[i], sizeof(ff_aac_codebook_vector_idx[i][0]),
sizeof(ff_aac_codebook_vector_idx[i][0]),
INIT_VLC_STATIC_OVERLONG);
offset += vlc_spectral[i].table_size;
}
@ -1796,7 +1798,6 @@ static int decode_spectrum_and_dequant(AACContext *ac, INTFLOAT coef[1024],
#if !USE_FIXED
const float *vq = ff_aac_codebook_vector_vals[cbt_m1];
#endif /* !USE_FIXED */
const uint16_t *cb_vector_idx = ff_aac_codebook_vector_idx[cbt_m1];
VLC_TYPE (*vlc_tab)[2] = vlc_spectral[cbt_m1].table;
OPEN_READER(re, gb);
@ -1812,7 +1813,7 @@ static int decode_spectrum_and_dequant(AACContext *ac, INTFLOAT coef[1024],
UPDATE_CACHE(re, gb);
GET_VLC(code, re, gb, vlc_tab, 8, 2);
cb_idx = cb_vector_idx[code];
cb_idx = code;
#if USE_FIXED
cf = DEC_SQUAD(cf, cb_idx);
#else
@ -1835,7 +1836,7 @@ static int decode_spectrum_and_dequant(AACContext *ac, INTFLOAT coef[1024],
UPDATE_CACHE(re, gb);
GET_VLC(code, re, gb, vlc_tab, 8, 2);
cb_idx = cb_vector_idx[code];
cb_idx = code;
nnz = cb_idx >> 8 & 15;
bits = nnz ? GET_CACHE(re, gb) : 0;
LAST_SKIP_BITS(re, gb, nnz);
@ -1859,7 +1860,7 @@ static int decode_spectrum_and_dequant(AACContext *ac, INTFLOAT coef[1024],
UPDATE_CACHE(re, gb);
GET_VLC(code, re, gb, vlc_tab, 8, 2);
cb_idx = cb_vector_idx[code];
cb_idx = code;
#if USE_FIXED
cf = DEC_SPAIR(cf, cb_idx);
#else
@ -1883,7 +1884,7 @@ static int decode_spectrum_and_dequant(AACContext *ac, INTFLOAT coef[1024],
UPDATE_CACHE(re, gb);
GET_VLC(code, re, gb, vlc_tab, 8, 2);
cb_idx = cb_vector_idx[code];
cb_idx = code;
nnz = cb_idx >> 8 & 15;
sign = nnz ? SHOW_UBITS(re, gb, nnz) << (cb_idx >> 12) : 0;
LAST_SKIP_BITS(re, gb, nnz);
@ -1916,14 +1917,14 @@ static int decode_spectrum_and_dequant(AACContext *ac, INTFLOAT coef[1024],
UPDATE_CACHE(re, gb);
GET_VLC(code, re, gb, vlc_tab, 8, 2);
cb_idx = code;
if (!code) {
if (cb_idx == 0x0000) {
*icf++ = 0;
*icf++ = 0;
continue;
}
cb_idx = cb_vector_idx[code];
nnz = cb_idx >> 12;
nzt = cb_idx >> 8;
bits = SHOW_UBITS(re, gb, nnz) << (32-nnz);

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