📄 ov518_decomp.c
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if (i > 16)
k = 32 - i;
while (k--)
C[i++] = 0;
} else {
k = skip;
if (skip > 31 - i)
k = 31 - i;
while (k--)
C[i++] = 0;
C[i++] = coeff;
}
} while (i <= 31);
if (skip == -1)
while (i <= 31) C[i++] = 0;
else
getACCoefficient(pIn, &coeff, cinfo, treeUVAC);
}
/******************************************************************************
* iDCT Functions
******************************************************************************/
#ifndef APPROXIMATE_MUL_BY_SHIFT
#define IDCT_MESSAGE "iDCT with multiply"
#define TIMES_16382(u) ((u)? 16382 * (u):0)
#define TIMES_23168(u) ((u)? 23168 * (u):0)
#define TIMES_30270(u) ((u)? 30270 * (u):0)
#define TIMES_41986(u) ((u)? 41986 * (u):0)
#define TIMES_35594(u) ((u)? 35594 * (u):0)
#define TIMES_23783(u) ((u)? 23783 * (u):0)
#define TIMES_8351(u) ((u)? 8351 * (u):0)
#define TIMES_17391(u) ((u)? 17391 * (u):0)
#define TIMES_14743(u) ((u)? 14743 * (u):0)
#define TIMES_9851(u) ((u)? 9851 * (u):0)
#define TIMES_3459(u) ((u)? 3459 * (u):0)
#define TIMES_32134(u) ((u)? 32134 * (u):0)
#define TIMES_27242(u) ((u)? 27242 * (u):0)
#define TIMES_18202(u) ((u)? 18202 * (u):0)
#define TIMES_6392(u) ((u)? 6392 * (u):0)
#define TIMES_39550(u) ((u)? 39550 * (u):0)
#define TIMES_6785(u) ((u)? 6785 * (u):0)
#define TIMES_12538(u) ((u)? 12538 * (u):0)
#else
#define IDCT_MESSAGE "iDCT with shift"
#define TIMES_16382(u) ( (u)? x=(u) , (x<<14) - (x<<1) :0 )
#define TIMES_23168(u) ( (u)? x=(u) , (x<<14) + (x<<12) + (x<<11) + (x<<9) :0 )
#define TIMES_30270(u) ( (u)? x=(u) , (x<<15) - (x<<11) :0 )
#define TIMES_41986(u) ( (u)? x=(u) , (x<<15) + (x<<13) + (x<<10) :0 )
#define TIMES_35594(u) ( (u)? x=(u) , (x<<15) + (x<<11) + (x<<9) + (x<<8) :0 )
#define TIMES_23783(u) ( (u)? x=(u) , (x<<14) + (x<<13) - (x<<9) - (x<<8) :0 )
#define TIMES_8351(u) ( (u)? x=(u) , (x<<13) :0 )
#define TIMES_17391(u) ( (u)? x=(u) , (x<<14) + (x<<10) :0 )
#define TIMES_14743(u) ( (u)? x=(u) , (x<<14) - (x<<10) - (x<<9) :0 )
#define TIMES_9851(u) ( (u)? x=(u) , (x<<13) + (x<<10) + (x<<9) :0 )
#define TIMES_3459(u) ( (u)? x=(u) , (x<<12) - (x<<9) :0 )
#define TIMES_32134(u) ( (u)? x=(u) , (x<<15) - (x<<9) :0 )
#define TIMES_27242(u) ( (u)? x=(u) , (x<<14) + (x<<13) + (x<<11) + (x<<9) :0 )
#define TIMES_18202(u) ( (u)? x=(u) , (x<<14) + (x<<11) - (x<<8) :0 )
#define TIMES_6392(u) ( (u)? x=(u) , (x<<13) - (x<<11) + (x<<8) :0 )
#define TIMES_39550(u) ( (u)? x=(u) , (x<<15) + (x<<12) + (x<<11) + (x<<9) :0 )
#define TIMES_6785(u) ( (u)? x=(u) , (x<<12) + (x<<11) + (x<<9) :0 )
#define TIMES_12538(u) ( (u)? x=(u) , (x<<13) + (x<<12) + (x<<8) :0 )
/*
* The variables C0, C4, C16 and C20 can also be removed from the algorithm
* if APPROXIMATE_MUL_BY_SHIFTS is defined. They store correction values
* and can be considered insignificant.
*/
#endif
static void
DCT_8x4(int *coeff, unsigned char *out)
/* pre: coeff == coefficients
post: coeff != coefficients
** DO NOT ASSUME coeff TO BE THE SAME BEFORE AND AFTER CALLING THIS FUNCTION!
*/
{
register int base,val1,val2,val3;
int tmp1,tmp2;
int C0,C4,C16,C20;
int C2_18,C6_22,C1_17,C3_19,C5_21,C7_23;
register int t;
#ifdef APPROXIMATE_MUL_BY_SHIFT
register int x;
#endif
C0=coeff[0];
C4=coeff[4];
C16=coeff[16];
C20=coeff[20];
coeff[0]=TIMES_23168(coeff[0]);
coeff[4]=TIMES_23168(coeff[4]);
coeff[16]=TIMES_23168(coeff[16]);
coeff[20]=TIMES_23168(coeff[20]);
C2_18 = coeff[2]+coeff[18];
C6_22 = coeff[6]+coeff[22];
C1_17 = coeff[1]+coeff[17];
C3_19 = coeff[3]+coeff[19];
C5_21 = coeff[5]+coeff[21];
C7_23 = coeff[7]+coeff[23];
// 0,7,25,32
base = 0x1000000;
base += coeff[0]+coeff[4]+coeff[16]+coeff[20];
base += TIMES_30270(C2_18);
base += TIMES_12538(C6_22);
val1 = TIMES_41986(coeff[9]);
val1 += TIMES_35594(coeff[11]);
val1 += TIMES_23783(coeff[13]);
val1 += TIMES_8351(coeff[15]);
val1 += TIMES_17391(coeff[25]);
val1 += TIMES_14743(coeff[27]);
val1 += TIMES_9851(coeff[29]);
val1 += TIMES_3459(coeff[31]);
val2 = TIMES_32134(C1_17);
val2 += TIMES_27242(C3_19);
val2 += TIMES_18202(C5_21);
val2 += TIMES_6392(C7_23);
val3 = TIMES_39550(coeff[10]);
val3 += TIMES_16382(coeff[14]+coeff[26]);
val3 += TIMES_6785(coeff[30]);
val3 += TIMES_30270(coeff[8]+coeff[12]);
val3 += TIMES_12538(coeff[24]+coeff[28]);
t=(base + val1 + val2 + val3) >> 17;
out[0]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base - val1 - val2 + val3 - C4 - C20) >> 17;
out[7]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base - val1 + val2 - val3 - C16- C20) >> 17;
out[24]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base + val1 - val2 - val3 - C4 - C16 - C20) >> 17;
out[31]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
//1,6,25,30
base = 0x1000000;
base += coeff[0]-coeff[4]+coeff[16]-coeff[20];
base += TIMES_12538(C2_18);
base -= TIMES_30270(C6_22);
val1 = TIMES_35594(coeff[9]);
val1 -= TIMES_8351(coeff[11]);
val1 -= TIMES_41986(coeff[13]);
val1 -= TIMES_23783(coeff[15]);
val1 -= TIMES_14743(coeff[25]);
val1 -= TIMES_3459(coeff[27]);
val1 -= TIMES_17391(coeff[29]);
val1 -= TIMES_9851(coeff[31]);
val2 = TIMES_27242(C1_17);
val2 -= TIMES_6392(C3_19);
val2 -= TIMES_32134(C5_21);
val2 -= TIMES_18202(C7_23);
val3 = TIMES_16382(coeff[10]-coeff[30]);
val3 -= TIMES_39550(coeff[14]);
val3 += TIMES_6785(coeff[26]);
val3 += TIMES_12538(coeff[24]-coeff[28]);
val3 += TIMES_30270(coeff[8]-coeff[12]);
t=(base + val1 + val2 + val3 + C4 + C20) >> 17;
out[1]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base - val1 - val2 + val3) >> 17;
out[6]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base - val1 + val2 - val3 + C4 - C16 + C20) >> 17;
out[25]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base + val1 - val2 - val3 + C20) >> 17;
out[30]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
//2,5,26,29
base = 0x1000000;
base += coeff[0] - coeff[4] + coeff[16] - coeff[20];
base -= TIMES_12538(C2_18);
base += TIMES_30270(C6_22);
val1 = TIMES_23783(coeff[9]);
val1 -= TIMES_41986(coeff[11]);
val1 += TIMES_8351(coeff[13]);
val1 += TIMES_35594(coeff[15]);
val1 += TIMES_9851(coeff[25]);
val1 -= TIMES_17391(coeff[27]);
val1 += TIMES_3459(coeff[29]);
val1 += TIMES_14743(coeff[31]);
val2 = TIMES_18202(C1_17);
val2 -= TIMES_32134(C3_19);
val2 += TIMES_6392(C5_21);
val2 += TIMES_27242(C7_23);
val3 = -TIMES_16382(coeff[10] - coeff[30]);
val3 += TIMES_39550(coeff[14]);
val3 -= TIMES_6785(coeff[26]);
val3 += TIMES_12538(coeff[24] - coeff[28]);
val3 += TIMES_30270(coeff[8] - coeff[12]);
t=(base + val1 + val2 + val3) >> 17;
out[2]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base - val1 - val2 + val3) >> 17;
out[5]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base - val1 + val2 - val3 - C16) >> 17;
out[26]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base + val1 - val2 - val3 + C4 - C16 + C20) >> 17;
out[29]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
//3,4,27,28
base = 0x1000000;
base += coeff[0] + coeff[4] + coeff[16] + coeff[20];
base -= TIMES_30270(C2_18);
base -= TIMES_12538(C6_22);
val1 = TIMES_8351(coeff[9]);
val1 -= TIMES_23783(coeff[11]);
val1 += TIMES_35594(coeff[13]);
val1 += TIMES_3459(coeff[25]);
val1 -= TIMES_9851(coeff[27]);
val1 += TIMES_14743(coeff[29]);
val2 = TIMES_6392(C1_17);
val2 -= TIMES_18202(C3_19);
val2 += TIMES_27242(C5_21);
val3 = -TIMES_39550(coeff[10]);
val3 += TIMES_16382(coeff[14] + coeff[26]);
val3 -= TIMES_6785(coeff[30]);
val3 += TIMES_30270(coeff[8] + coeff[12]);
val3 += TIMES_12538(coeff[24] + coeff[28]);
tmp1 = TIMES_32134(C7_23);
tmp2 = TIMES_41986(coeff[15]) + TIMES_17391(coeff[31]);
t=(base + val1 + val2 + val3 - tmp1 - tmp2 - C4 - C20) >> 17;
out[3]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base - val1 - val2 + val3) >> 17;
out[4]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base - val1 + val2 - val3 - tmp1 + tmp2) >> 17;
out[27]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base + val1 - val2 - val3 - C16 - C20) >> 17;
out[28]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
// Second half
C2_18 = coeff[2] - coeff[18];
C6_22 = coeff[6] - coeff[22];
C1_17 = coeff[1] - coeff[17];
C3_19 = coeff[3] - coeff[19];
C5_21 = coeff[5] - coeff[21];
C7_23 = coeff[7] - coeff[23];
// 8,15,16,23
base = 0x1000000;
base += coeff[0] + coeff[4] - coeff[16] - coeff[20];
base +=TIMES_30270(C2_18);
base +=TIMES_12538(C6_22);
val1 = TIMES_17391(coeff[9]);
val1 += TIMES_14743(coeff[11]);
val1 += TIMES_9851(coeff[13]);
val1 += TIMES_3459(coeff[15]);
val1 -= TIMES_41986(coeff[25]);
val1 -= TIMES_35594(coeff[27]);
val1 -= TIMES_23783(coeff[29]);
val1 -= TIMES_8351(coeff[31]);
val2 = TIMES_32134(C1_17);
val2 += TIMES_27242(C3_19);
val2 += TIMES_18202(C5_21);
val2 += TIMES_6392(C7_23);
val3 = TIMES_16382(coeff[10] - coeff[30]);
val3 += TIMES_6785(coeff[14]);
val3 -= TIMES_39550(coeff[26]);
val3 -=TIMES_30270(coeff[24] + coeff[28]);
val3 +=TIMES_12538(coeff[8] + coeff[12]);
t=(base + val1 + val2 + val3) >> 17;
out[8]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base - val1 - val2 + val3 - C4 + C16 + C20) >> 17;
out[15]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base - val1 + val2 - val3) >> 17;
out[16]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base + val1 - val2 - val3 - C4 + C20) >> 17;
out[23]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
//9,14,17,22
base = 0x1000000;
base += coeff[0] - coeff[4] - coeff[16] + coeff[20];
base += TIMES_12538(C2_18);
base -= TIMES_30270(C6_22);
val1 = TIMES_14743(coeff[9]);
val1 -= TIMES_3459(coeff[11]);
val1 -= TIMES_17391(coeff[13]);
val1 -= TIMES_9851(coeff[15]);
val1 -= TIMES_35594(coeff[25]);
val1 += TIMES_8351(coeff[27]);
val1 += TIMES_41986(coeff[29]);
val1 += TIMES_23783(coeff[31]);
val2 = TIMES_27242(C1_17);
val2 -= TIMES_6392(C3_19);
val2 -= TIMES_32134(C5_21);
val2 -= TIMES_18202(C7_23);
val3 = TIMES_6785(coeff[10]);
val3 -= TIMES_16382(coeff[14] + coeff[26]);
val3 += TIMES_39550(coeff[30]);
val3 += TIMES_12538(coeff[8] - coeff[12]);
val3 -= TIMES_30270(coeff[24] - coeff[28]);
t=(base + val1 + val2 + val3 + C4 + C16 - C20) >> 17;
out[9]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base - val1 - val2 + val3 + C16) >> 17;
out[14]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base - val1 + val2 - val3 + C4) >> 17;
out[17]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base + val1 - val2 - val3) >> 17;
out[22]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
//10,13,18,21
base = 0x1000000;
base += coeff[0] - coeff[4] - coeff[16] + coeff[20];
base -= TIMES_12538(C2_18);
base += TIMES_30270(C6_22);
val1 = TIMES_9851(coeff[9]);
val1 -= TIMES_17391(coeff[11]);
val1 += TIMES_3459(coeff[13]);
val1 += TIMES_14743(coeff[15]);
val1 -= TIMES_23783(coeff[25]);
val1 += TIMES_41986(coeff[27]);
val1 -= TIMES_8351(coeff[29]);
val1 -= TIMES_35594(coeff[31]);
val2 = TIMES_18202(C1_17);
val2 -= TIMES_32134(C3_19);
val2 += TIMES_6392(C5_21);
val2 += TIMES_27242(C7_23);
val3 = -TIMES_6785(coeff[10]);
val3 += TIMES_16382(coeff[14]+coeff[26]);
val3 -= TIMES_39550(coeff[30]);
val3 += TIMES_12538(coeff[8]-coeff[12]);
val3 -= TIMES_30270(coeff[24]-coeff[28]);
t=(base + val1 + val2 + val3) >> 17;
out[10]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base - val1 - val2 + val3 + C4 + C16 - C20) >> 17;
out[13]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base - val1 + val2 - val3) >> 17;
out[18]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base + val1 - val2 - val3 + C4) >> 17;
out[21]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
// 11,12,19,20
base = 0x1000000;
base += coeff[0]+coeff[4]-coeff[16]-coeff[20];
base -= TIMES_30270(C2_18);
base -= TIMES_12538(C6_22);
val1 = TIMES_3459(coeff[9]);
val1 -= TIMES_9851(coeff[11]);
val1 += TIMES_14743(coeff[13]);
val1 -= TIMES_8351(coeff[25]);
val1 += TIMES_23783(coeff[27]);
val1 -= TIMES_35594(coeff[29]);
val2 = TIMES_6392(C1_17);
val2 -= TIMES_18202(C3_19);
val2 += TIMES_27242(C5_21);
val3 = -TIMES_16382(coeff[10] - coeff[30]);
val3 -= TIMES_6785(coeff[14]);
val3 += TIMES_39550(coeff[26]);
val3 -= TIMES_30270(coeff[24]+coeff[28]);
val3 += TIMES_12538(coeff[8]+coeff[12]);
tmp1 = TIMES_32134(C7_23);
tmp2 = -TIMES_17391(coeff[15]) + TIMES_41986(coeff[31]);
t=(base + val1 + val2 + val3 - tmp1 + tmp2 + C16 + C20) >> 17;
out[11]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
t=(base - val1 - val2 + val3 + C16 + C20) >> 17;
out[12]= t&0xFFFFFF00? t<0?0:255 : (unsigned char)t;
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