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| author | Kostya Shishkov <kostya.shishkov@gmail.com> | 2012-03-24 07:29:51 +0100 |
|---|---|---|
| committer | Kostya Shishkov <kostya.shishkov@gmail.com> | 2012-03-24 11:53:26 +0100 |
| commit | 494bce6224c7da6a174fb16a49ed26e5aab32af1 (patch) | |
| tree | 7e819bec254d031b85bd7348ad7c547a6d0c8ed3 | |
| parent | cb7190cd2c691fd93e4d3664f3fce6c19ee001dd (diff) | |
| download | ffmpeg-494bce6224c7da6a174fb16a49ed26e5aab32af1.tar.gz | |
ralf: read Huffman code lengths without GetBitContext
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.
| -rw-r--r-- | libavcodec/ralf.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/libavcodec/ralf.c b/libavcodec/ralf.c index 38e7e69cb7..0e5b04663f 100644 --- a/libavcodec/ralf.c +++ b/libavcodec/ralf.c @@ -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++) |