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ralf: read Huffman code lengths without GetBitContext

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Those descriptions are stored in nibbles, so they are easy to extract.
And this way we don't need to pad tables for possible bit reader overreads.
This commit is contained in:
Kostya Shishkov 2012-03-24 07:29:51 +01:00
parent cb7190cd2c
commit 494bce6224
1 changed files with 4 additions and 4 deletions
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8
libavcodec/ralf.c
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@ -80,17 +80,17 @@ static int init_ralf_vlc(VLC *vlc, const uint8_t *data, int elems)
int counts[17], prefixes[18];
int i, cur_len;
int max_bits = 0;
GetBitContext gb;
init_get_bits(&gb, data, elems * 4);
int nb = 0;
for (i = 0; i <= 16; i++)
counts[i] = 0;
for (i = 0; i < elems; i++) {
cur_len = get_bits(&gb, 4) + 1;
cur_len = (nb ? *data & 0xF : *data >> 4) + 1;
counts[cur_len]++;
max_bits = FFMAX(max_bits, cur_len);
lens[i] = cur_len;
data += nb;
nb ^= 1;
}
prefixes[1] = 0;
for (i = 1; i <= 16; i++)