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diracdec: simplify golomb parsing and dequantization

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In preparation for the following commits, this commit simplifies the
coefficient parsing and dequantization function. It was needlessly
inlined without much performance gain.

Signed-off-by: Rostislav Pehlivanov <rpehlivanov@obe.tv>
This commit is contained in:
Rostislav Pehlivanov 2016-06-23 18:06:57 +01:00 committed by Rostislav Pehlivanov
parent bd61f3c6bf
commit 17caae7202
1 changed files with 6 additions and 47 deletions
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53
libavcodec/diracdec.c
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@ -406,58 +406,17 @@ static av_cold int dirac_decode_end(AVCodecContext *avctx)
return 0;
}
#define SIGN_CTX(x) (CTX_SIGN_ZERO + ((x) > 0) - ((x) < 0))
static inline int coeff_unpack_golomb(GetBitContext *gb, int qfactor, int qoffset)
{
int sign, coeff;
uint32_t buf;
OPEN_READER(re, gb);
UPDATE_CACHE(re, gb);
buf = GET_CACHE(re, gb);
if (buf & 0x80000000) {
LAST_SKIP_BITS(re,gb,1);
CLOSE_READER(re, gb);
return 0;
}
if (buf & 0xAA800000) {
buf >>= 32 - 8;
SKIP_BITS(re, gb, ff_interleaved_golomb_vlc_len[buf]);
coeff = ff_interleaved_ue_golomb_vlc_code[buf];
} else {
unsigned ret = 1;
do {
buf >>= 32 - 8;
SKIP_BITS(re, gb,
FFMIN(ff_interleaved_golomb_vlc_len[buf], 8));
if (ff_interleaved_golomb_vlc_len[buf] != 9) {
ret <<= (ff_interleaved_golomb_vlc_len[buf] - 1) >> 1;
ret |= ff_interleaved_dirac_golomb_vlc_code[buf];
break;
}
ret = (ret << 4) | ff_interleaved_dirac_golomb_vlc_code[buf];
UPDATE_CACHE(re, gb);
buf = GET_CACHE(re, gb);
} while (ret<0x8000000U && BITS_AVAILABLE(re, gb));
coeff = ret - 1;
}
coeff = (coeff * qfactor + qoffset) >> 2;
sign = SHOW_SBITS(re, gb, 1);
LAST_SKIP_BITS(re, gb, 1);
coeff = (coeff ^ sign) - sign;
CLOSE_READER(re, gb);
int coeff = dirac_get_se_golomb(gb);
const int sign = FFSIGN(coeff);
if (coeff)
coeff = sign*((sign * coeff * qfactor + qoffset) >> 2);
return coeff;
}
#define SIGN_CTX(x) (CTX_SIGN_ZERO + ((x) > 0) - ((x) < 0))
#define UNPACK_ARITH(n, type) \
static inline void coeff_unpack_arith_##n(DiracArith *c, int qfactor, int qoffset, \
SubBand *b, type *buf, int x, int y) \