generic-library/ffmpeg
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replace a few MULL by MULH

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Originally committed as revision 6039 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer 2006-08-21 12:12:43 +00:00
parent f6e712961f
commit eb6447766d
1 changed files with 24 additions and 11 deletions
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35
libavcodec/mpegaudiodec.c
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@ -943,6 +943,19 @@ static const int icos36[9] = {
FIXR(5.73685662283492756461),
};
/* 0.5 / cos(pi*(2*i+1)/36) */
static const int icos36h[9] = {
FIXHR(0.50190991877167369479/2),
FIXHR(0.51763809020504152469/2), //0
FIXHR(0.55168895948124587824/2),
FIXHR(0.61038729438072803416/2),
FIXHR(0.70710678118654752439/2), //1
FIXHR(0.87172339781054900991/2),
FIXHR(1.18310079157624925896/4),
FIXHR(1.93185165257813657349/4), //2
// FIXHR(5.73685662283492756461),
};
/* 12 points IMDCT. We compute it "by hand" by factorizing obvious
cases. */
static void imdct12(int *out, int *in)
@ -959,10 +972,10 @@ static void imdct12(int *out, int *in)
in3 += in1;
in2= MULH(2*in2, C3);
in3= MULH(2*in3, C3);
in3= MULH(4*in3, C3);
t1 = in0 - in4;
t2 = MULL(in1 - in5, icos36[4]);
t2 = MULH(2*(in1 - in5), icos36h[4]);
out[ 7]=
out[10]= t1 + t2;
@ -971,19 +984,19 @@ static void imdct12(int *out, int *in)
in0 += in4>>1;
in4 = in0 + in2;
in1 += in5>>1;
in5 = MULL(in1 + in3, icos36[1]);
in5 += 2*in1;
in1 = MULH(in5 + in3, icos36h[1]);
out[ 8]=
out[ 9]= in4 + in5;
out[ 9]= in4 + in1;
out[ 2]=
out[ 3]= in4 - in5;
out[ 3]= in4 - in1;
in0 -= in2;
in1 = MULL(in1 - in3, icos36[7]);
in5 = MULH(2*(in5 - in3), icos36h[7]);
out[ 0]=
out[ 5]= in0 - in1;
out[ 5]= in0 - in5;
out[ 6]=
out[11]= in0 + in1;
out[11]= in0 + in5;
}
/* cos(pi*i/18) */
@ -1077,7 +1090,7 @@ static void imdct36(int *out, int *buf, int *in, int *win)
t2 = tmp[i + 1];
t3 = tmp[i + 3];
s1 = MULL(t3 + t2, icos36[j]);
s1 = MULH(2*(t3 + t2), icos36h[j]);
s3 = MULL(t3 - t2, icos36[8 - j]);
t0 = s0 + s1;
@ -1097,7 +1110,7 @@ static void imdct36(int *out, int *buf, int *in, int *win)
}
s0 = tmp[16];
s1 = MULL(tmp[17], icos36[4]);
s1 = MULH(2*tmp[17], icos36h[4]);
t0 = s0 + s1;
t1 = s0 - s1;
out[(9 + 4)*SBLIMIT] = MULH(t1, win[9 + 4]) + buf[9 + 4];