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avcodec/huffyuvdec: optimize >8bps VLC reading

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97479 -> 54891 decicycles

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2014-01-26 19:53:14 +01:00
parent 37baa2af43
commit e6c0da70fc
1 changed files with 13 additions and 3 deletions
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16
libavcodec/huffyuvdec.c
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@ -125,14 +125,18 @@ static int generate_joint_tables(HYuvContext *s)
int limit = VLC_BITS - len0;
if(limit <= 0 || !len0)
continue;
if((sign_extend(y, 8) & (s->vlc_n-1)) != y)
continue;
for (u = 0; u < s->vlc_n; u++) {
int len1 = s->len[p][u];
if (len1 > limit || !len1)
continue;
if((sign_extend(u, 8) & (s->vlc_n-1)) != u)
continue;
av_assert0(i < (1 << VLC_BITS));
len[i] = len0 + len1;
bits[i] = (s->bits[p0][y] << len1) + s->bits[p][u];
symbols[i] = (y << 8) + u; //FIXME
symbols[i] = (y << 8) + (u & 0xFF);
if(symbols[i] != 0xffff) // reserved to mean "invalid"
i++;
}
@ -581,8 +585,14 @@ static void decode_422_bitstream(HYuvContext *s, int count)
}\
}
#define READ_2PIX_PLANE14(dst0, dst1, plane){\
dst0 = get_vlc2(&s->gb, s->vlc[plane].table, VLC_BITS, 3);\
dst1 = get_vlc2(&s->gb, s->vlc[plane].table, VLC_BITS, 3);\
int16_t code = get_vlc2(&s->gb, s->vlc[4+plane].table, VLC_BITS, 1);\
if(code != (int16_t)0xffff){\
dst0 = code>>8;\
dst1 = sign_extend(code, 8);\
}else{\
dst0 = get_vlc2(&s->gb, s->vlc[plane].table, VLC_BITS, 3);\
dst1 = get_vlc2(&s->gb, s->vlc[plane].table, VLC_BITS, 3);\
}\
}
#define READ_2PIX_PLANE16(dst0, dst1, plane){\