Alien-FreeImage
view release on metacpan or search on metacpan
src/Source/LibJPEG/jfdctint.c view on Meta::CPAN
tmp0 = tmp1 - tmp2;
tmp1 += tmp2;
tmp2 = MULTIPLY(tmp11 + tmp12, - FIX(1.378756276)); /* -c1 */
tmp1 += tmp2;
tmp3 = MULTIPLY(tmp10 + tmp12, FIX(0.613604268)); /* c5 */
tmp0 += tmp3;
tmp2 += tmp3 + MULTIPLY(tmp12, FIX(1.870828693)); /* c3+c1-c5 */
dataptr[1] = (DCTELEM) DESCALE(tmp0, CONST_BITS-PASS1_BITS);
dataptr[3] = (DCTELEM) DESCALE(tmp1, CONST_BITS-PASS1_BITS);
dataptr[5] = (DCTELEM) DESCALE(tmp2, CONST_BITS-PASS1_BITS);
dataptr += DCTSIZE; /* advance pointer to next row */
}
/* Pass 2: process columns.
* We remove the PASS1_BITS scaling, but leave the results scaled up
* by an overall factor of 8.
* We must also scale the output by (8/7)**2 = 64/49, which we fold
* into the constant multipliers:
* cK now represents sqrt(2) * cos(K*pi/14) * 64/49.
*/
dataptr = data;
for (ctr = 0; ctr < 7; ctr++) {
/* Even part */
tmp0 = dataptr[DCTSIZE*0] + dataptr[DCTSIZE*6];
tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*5];
tmp2 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*4];
tmp3 = dataptr[DCTSIZE*3];
tmp10 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*6];
tmp11 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*5];
tmp12 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*4];
z1 = tmp0 + tmp2;
dataptr[DCTSIZE*0] = (DCTELEM)
DESCALE(MULTIPLY(z1 + tmp1 + tmp3, FIX(1.306122449)), /* 64/49 */
CONST_BITS+PASS1_BITS);
tmp3 += tmp3;
z1 -= tmp3;
z1 -= tmp3;
z1 = MULTIPLY(z1, FIX(0.461784020)); /* (c2+c6-c4)/2 */
z2 = MULTIPLY(tmp0 - tmp2, FIX(1.202428084)); /* (c2+c4-c6)/2 */
z3 = MULTIPLY(tmp1 - tmp2, FIX(0.411026446)); /* c6 */
dataptr[DCTSIZE*2] = (DCTELEM) DESCALE(z1 + z2 + z3, CONST_BITS+PASS1_BITS);
z1 -= z2;
z2 = MULTIPLY(tmp0 - tmp1, FIX(1.151670509)); /* c4 */
dataptr[DCTSIZE*4] = (DCTELEM)
DESCALE(z2 + z3 - MULTIPLY(tmp1 - tmp3, FIX(0.923568041)), /* c2+c6-c4 */
CONST_BITS+PASS1_BITS);
dataptr[DCTSIZE*6] = (DCTELEM) DESCALE(z1 + z2, CONST_BITS+PASS1_BITS);
/* Odd part */
tmp1 = MULTIPLY(tmp10 + tmp11, FIX(1.221765677)); /* (c3+c1-c5)/2 */
tmp2 = MULTIPLY(tmp10 - tmp11, FIX(0.222383464)); /* (c3+c5-c1)/2 */
tmp0 = tmp1 - tmp2;
tmp1 += tmp2;
tmp2 = MULTIPLY(tmp11 + tmp12, - FIX(1.800824523)); /* -c1 */
tmp1 += tmp2;
tmp3 = MULTIPLY(tmp10 + tmp12, FIX(0.801442310)); /* c5 */
tmp0 += tmp3;
tmp2 += tmp3 + MULTIPLY(tmp12, FIX(2.443531355)); /* c3+c1-c5 */
dataptr[DCTSIZE*1] = (DCTELEM) DESCALE(tmp0, CONST_BITS+PASS1_BITS);
dataptr[DCTSIZE*3] = (DCTELEM) DESCALE(tmp1, CONST_BITS+PASS1_BITS);
dataptr[DCTSIZE*5] = (DCTELEM) DESCALE(tmp2, CONST_BITS+PASS1_BITS);
dataptr++; /* advance pointer to next column */
}
}
/*
* Perform the forward DCT on a 6x6 sample block.
*/
GLOBAL(void)
jpeg_fdct_6x6 (DCTELEM * data, JSAMPARRAY sample_data, JDIMENSION start_col)
{
INT32 tmp0, tmp1, tmp2;
INT32 tmp10, tmp11, tmp12;
DCTELEM *dataptr;
JSAMPROW elemptr;
int ctr;
SHIFT_TEMPS
/* Pre-zero output coefficient block. */
MEMZERO(data, SIZEOF(DCTELEM) * DCTSIZE2);
/* Pass 1: process rows.
* Note results are scaled up by sqrt(8) compared to a true DCT;
* furthermore, we scale the results by 2**PASS1_BITS.
* cK represents sqrt(2) * cos(K*pi/12).
*/
dataptr = data;
for (ctr = 0; ctr < 6; ctr++) {
elemptr = sample_data[ctr] + start_col;
/* Even part */
tmp0 = GETJSAMPLE(elemptr[0]) + GETJSAMPLE(elemptr[5]);
tmp11 = GETJSAMPLE(elemptr[1]) + GETJSAMPLE(elemptr[4]);
tmp2 = GETJSAMPLE(elemptr[2]) + GETJSAMPLE(elemptr[3]);
tmp10 = tmp0 + tmp2;
tmp12 = tmp0 - tmp2;
tmp0 = GETJSAMPLE(elemptr[0]) - GETJSAMPLE(elemptr[5]);
tmp1 = GETJSAMPLE(elemptr[1]) - GETJSAMPLE(elemptr[4]);
tmp2 = GETJSAMPLE(elemptr[2]) - GETJSAMPLE(elemptr[3]);
/* Apply unsigned->signed conversion */
dataptr[0] = (DCTELEM)
((tmp10 + tmp11 - 6 * CENTERJSAMPLE) << PASS1_BITS);
dataptr[2] = (DCTELEM)
DESCALE(MULTIPLY(tmp12, FIX(1.224744871)), /* c2 */
CONST_BITS-PASS1_BITS);
src/Source/LibJPEG/jfdctint.c view on Meta::CPAN
data[0] = (DCTELEM)
((GETJSAMPLE(sample_data[0][start_col]) - CENTERJSAMPLE) << 6);
}
/*
* Perform the forward DCT on a 9x9 sample block.
*/
GLOBAL(void)
jpeg_fdct_9x9 (DCTELEM * data, JSAMPARRAY sample_data, JDIMENSION start_col)
{
INT32 tmp0, tmp1, tmp2, tmp3, tmp4;
INT32 tmp10, tmp11, tmp12, tmp13;
INT32 z1, z2;
DCTELEM workspace[8];
DCTELEM *dataptr;
DCTELEM *wsptr;
JSAMPROW elemptr;
int ctr;
SHIFT_TEMPS
/* Pass 1: process rows.
* Note results are scaled up by sqrt(8) compared to a true DCT;
* we scale the results further by 2 as part of output adaption
* scaling for different DCT size.
* cK represents sqrt(2) * cos(K*pi/18).
*/
dataptr = data;
ctr = 0;
for (;;) {
elemptr = sample_data[ctr] + start_col;
/* Even part */
tmp0 = GETJSAMPLE(elemptr[0]) + GETJSAMPLE(elemptr[8]);
tmp1 = GETJSAMPLE(elemptr[1]) + GETJSAMPLE(elemptr[7]);
tmp2 = GETJSAMPLE(elemptr[2]) + GETJSAMPLE(elemptr[6]);
tmp3 = GETJSAMPLE(elemptr[3]) + GETJSAMPLE(elemptr[5]);
tmp4 = GETJSAMPLE(elemptr[4]);
tmp10 = GETJSAMPLE(elemptr[0]) - GETJSAMPLE(elemptr[8]);
tmp11 = GETJSAMPLE(elemptr[1]) - GETJSAMPLE(elemptr[7]);
tmp12 = GETJSAMPLE(elemptr[2]) - GETJSAMPLE(elemptr[6]);
tmp13 = GETJSAMPLE(elemptr[3]) - GETJSAMPLE(elemptr[5]);
z1 = tmp0 + tmp2 + tmp3;
z2 = tmp1 + tmp4;
/* Apply unsigned->signed conversion */
dataptr[0] = (DCTELEM) ((z1 + z2 - 9 * CENTERJSAMPLE) << 1);
dataptr[6] = (DCTELEM)
DESCALE(MULTIPLY(z1 - z2 - z2, FIX(0.707106781)), /* c6 */
CONST_BITS-1);
z1 = MULTIPLY(tmp0 - tmp2, FIX(1.328926049)); /* c2 */
z2 = MULTIPLY(tmp1 - tmp4 - tmp4, FIX(0.707106781)); /* c6 */
dataptr[2] = (DCTELEM)
DESCALE(MULTIPLY(tmp2 - tmp3, FIX(1.083350441)) /* c4 */
+ z1 + z2, CONST_BITS-1);
dataptr[4] = (DCTELEM)
DESCALE(MULTIPLY(tmp3 - tmp0, FIX(0.245575608)) /* c8 */
+ z1 - z2, CONST_BITS-1);
/* Odd part */
dataptr[3] = (DCTELEM)
DESCALE(MULTIPLY(tmp10 - tmp12 - tmp13, FIX(1.224744871)), /* c3 */
CONST_BITS-1);
tmp11 = MULTIPLY(tmp11, FIX(1.224744871)); /* c3 */
tmp0 = MULTIPLY(tmp10 + tmp12, FIX(0.909038955)); /* c5 */
tmp1 = MULTIPLY(tmp10 + tmp13, FIX(0.483689525)); /* c7 */
dataptr[1] = (DCTELEM) DESCALE(tmp11 + tmp0 + tmp1, CONST_BITS-1);
tmp2 = MULTIPLY(tmp12 - tmp13, FIX(1.392728481)); /* c1 */
dataptr[5] = (DCTELEM) DESCALE(tmp0 - tmp11 - tmp2, CONST_BITS-1);
dataptr[7] = (DCTELEM) DESCALE(tmp1 - tmp11 + tmp2, CONST_BITS-1);
ctr++;
if (ctr != DCTSIZE) {
if (ctr == 9)
break; /* Done. */
dataptr += DCTSIZE; /* advance pointer to next row */
} else
dataptr = workspace; /* switch pointer to extended workspace */
}
/* Pass 2: process columns.
* We leave the results scaled up by an overall factor of 8.
* We must also scale the output by (8/9)**2 = 64/81, which we partially
* fold into the constant multipliers and final/initial shifting:
* cK now represents sqrt(2) * cos(K*pi/18) * 128/81.
*/
dataptr = data;
wsptr = workspace;
for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
/* Even part */
tmp0 = dataptr[DCTSIZE*0] + wsptr[DCTSIZE*0];
tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*7];
tmp2 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*6];
tmp3 = dataptr[DCTSIZE*3] + dataptr[DCTSIZE*5];
tmp4 = dataptr[DCTSIZE*4];
tmp10 = dataptr[DCTSIZE*0] - wsptr[DCTSIZE*0];
tmp11 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*7];
tmp12 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*6];
tmp13 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*5];
z1 = tmp0 + tmp2 + tmp3;
z2 = tmp1 + tmp4;
dataptr[DCTSIZE*0] = (DCTELEM)
DESCALE(MULTIPLY(z1 + z2, FIX(1.580246914)), /* 128/81 */
CONST_BITS+2);
dataptr[DCTSIZE*6] = (DCTELEM)
DESCALE(MULTIPLY(z1 - z2 - z2, FIX(1.117403309)), /* c6 */
CONST_BITS+2);
src/Source/LibJPEG/jfdctint.c view on Meta::CPAN
DCTELEM *dataptr;
DCTELEM *wsptr;
JSAMPROW elemptr;
int ctr;
SHIFT_TEMPS
/* Pass 1: process rows.
* Note results are scaled up by sqrt(8) compared to a true DCT;
* we scale the results further by 2 as part of output adaption
* scaling for different DCT size.
* cK represents sqrt(2) * cos(K*pi/20).
*/
dataptr = data;
ctr = 0;
for (;;) {
elemptr = sample_data[ctr] + start_col;
/* Even part */
tmp0 = GETJSAMPLE(elemptr[0]) + GETJSAMPLE(elemptr[9]);
tmp1 = GETJSAMPLE(elemptr[1]) + GETJSAMPLE(elemptr[8]);
tmp12 = GETJSAMPLE(elemptr[2]) + GETJSAMPLE(elemptr[7]);
tmp3 = GETJSAMPLE(elemptr[3]) + GETJSAMPLE(elemptr[6]);
tmp4 = GETJSAMPLE(elemptr[4]) + GETJSAMPLE(elemptr[5]);
tmp10 = tmp0 + tmp4;
tmp13 = tmp0 - tmp4;
tmp11 = tmp1 + tmp3;
tmp14 = tmp1 - tmp3;
tmp0 = GETJSAMPLE(elemptr[0]) - GETJSAMPLE(elemptr[9]);
tmp1 = GETJSAMPLE(elemptr[1]) - GETJSAMPLE(elemptr[8]);
tmp2 = GETJSAMPLE(elemptr[2]) - GETJSAMPLE(elemptr[7]);
tmp3 = GETJSAMPLE(elemptr[3]) - GETJSAMPLE(elemptr[6]);
tmp4 = GETJSAMPLE(elemptr[4]) - GETJSAMPLE(elemptr[5]);
/* Apply unsigned->signed conversion */
dataptr[0] = (DCTELEM)
((tmp10 + tmp11 + tmp12 - 10 * CENTERJSAMPLE) << 1);
tmp12 += tmp12;
dataptr[4] = (DCTELEM)
DESCALE(MULTIPLY(tmp10 - tmp12, FIX(1.144122806)) - /* c4 */
MULTIPLY(tmp11 - tmp12, FIX(0.437016024)), /* c8 */
CONST_BITS-1);
tmp10 = MULTIPLY(tmp13 + tmp14, FIX(0.831253876)); /* c6 */
dataptr[2] = (DCTELEM)
DESCALE(tmp10 + MULTIPLY(tmp13, FIX(0.513743148)), /* c2-c6 */
CONST_BITS-1);
dataptr[6] = (DCTELEM)
DESCALE(tmp10 - MULTIPLY(tmp14, FIX(2.176250899)), /* c2+c6 */
CONST_BITS-1);
/* Odd part */
tmp10 = tmp0 + tmp4;
tmp11 = tmp1 - tmp3;
dataptr[5] = (DCTELEM) ((tmp10 - tmp11 - tmp2) << 1);
tmp2 <<= CONST_BITS;
dataptr[1] = (DCTELEM)
DESCALE(MULTIPLY(tmp0, FIX(1.396802247)) + /* c1 */
MULTIPLY(tmp1, FIX(1.260073511)) + tmp2 + /* c3 */
MULTIPLY(tmp3, FIX(0.642039522)) + /* c7 */
MULTIPLY(tmp4, FIX(0.221231742)), /* c9 */
CONST_BITS-1);
tmp12 = MULTIPLY(tmp0 - tmp4, FIX(0.951056516)) - /* (c3+c7)/2 */
MULTIPLY(tmp1 + tmp3, FIX(0.587785252)); /* (c1-c9)/2 */
tmp13 = MULTIPLY(tmp10 + tmp11, FIX(0.309016994)) + /* (c3-c7)/2 */
(tmp11 << (CONST_BITS - 1)) - tmp2;
dataptr[3] = (DCTELEM) DESCALE(tmp12 + tmp13, CONST_BITS-1);
dataptr[7] = (DCTELEM) DESCALE(tmp12 - tmp13, CONST_BITS-1);
ctr++;
if (ctr != DCTSIZE) {
if (ctr == 10)
break; /* Done. */
dataptr += DCTSIZE; /* advance pointer to next row */
} else
dataptr = workspace; /* switch pointer to extended workspace */
}
/* Pass 2: process columns.
* We leave the results scaled up by an overall factor of 8.
* We must also scale the output by (8/10)**2 = 16/25, which we partially
* fold into the constant multipliers and final/initial shifting:
* cK now represents sqrt(2) * cos(K*pi/20) * 32/25.
*/
dataptr = data;
wsptr = workspace;
for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
/* Even part */
tmp0 = dataptr[DCTSIZE*0] + wsptr[DCTSIZE*1];
tmp1 = dataptr[DCTSIZE*1] + wsptr[DCTSIZE*0];
tmp12 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*7];
tmp3 = dataptr[DCTSIZE*3] + dataptr[DCTSIZE*6];
tmp4 = dataptr[DCTSIZE*4] + dataptr[DCTSIZE*5];
tmp10 = tmp0 + tmp4;
tmp13 = tmp0 - tmp4;
tmp11 = tmp1 + tmp3;
tmp14 = tmp1 - tmp3;
tmp0 = dataptr[DCTSIZE*0] - wsptr[DCTSIZE*1];
tmp1 = dataptr[DCTSIZE*1] - wsptr[DCTSIZE*0];
tmp2 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*7];
tmp3 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*6];
tmp4 = dataptr[DCTSIZE*4] - dataptr[DCTSIZE*5];
dataptr[DCTSIZE*0] = (DCTELEM)
DESCALE(MULTIPLY(tmp10 + tmp11 + tmp12, FIX(1.28)), /* 32/25 */
CONST_BITS+2);
tmp12 += tmp12;
dataptr[DCTSIZE*4] = (DCTELEM)
DESCALE(MULTIPLY(tmp10 - tmp12, FIX(1.464477191)) - /* c4 */
MULTIPLY(tmp11 - tmp12, FIX(0.559380511)), /* c8 */
CONST_BITS+2);
tmp10 = MULTIPLY(tmp13 + tmp14, FIX(1.064004961)); /* c6 */
dataptr[DCTSIZE*2] = (DCTELEM)
src/Source/LibJPEG/jfdctint.c view on Meta::CPAN
* cK now represents sqrt(2) * cos(K*pi/26) * 128/169.
*/
dataptr = data;
wsptr = workspace;
for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
/* Even part */
tmp0 = dataptr[DCTSIZE*0] + wsptr[DCTSIZE*4];
tmp1 = dataptr[DCTSIZE*1] + wsptr[DCTSIZE*3];
tmp2 = dataptr[DCTSIZE*2] + wsptr[DCTSIZE*2];
tmp3 = dataptr[DCTSIZE*3] + wsptr[DCTSIZE*1];
tmp4 = dataptr[DCTSIZE*4] + wsptr[DCTSIZE*0];
tmp5 = dataptr[DCTSIZE*5] + dataptr[DCTSIZE*7];
tmp6 = dataptr[DCTSIZE*6];
tmp10 = dataptr[DCTSIZE*0] - wsptr[DCTSIZE*4];
tmp11 = dataptr[DCTSIZE*1] - wsptr[DCTSIZE*3];
tmp12 = dataptr[DCTSIZE*2] - wsptr[DCTSIZE*2];
tmp13 = dataptr[DCTSIZE*3] - wsptr[DCTSIZE*1];
tmp14 = dataptr[DCTSIZE*4] - wsptr[DCTSIZE*0];
tmp15 = dataptr[DCTSIZE*5] - dataptr[DCTSIZE*7];
dataptr[DCTSIZE*0] = (DCTELEM)
DESCALE(MULTIPLY(tmp0 + tmp1 + tmp2 + tmp3 + tmp4 + tmp5 + tmp6,
FIX(0.757396450)), /* 128/169 */
CONST_BITS+1);
tmp6 += tmp6;
tmp0 -= tmp6;
tmp1 -= tmp6;
tmp2 -= tmp6;
tmp3 -= tmp6;
tmp4 -= tmp6;
tmp5 -= tmp6;
dataptr[DCTSIZE*2] = (DCTELEM)
DESCALE(MULTIPLY(tmp0, FIX(1.039995521)) + /* c2 */
MULTIPLY(tmp1, FIX(0.801745081)) + /* c6 */
MULTIPLY(tmp2, FIX(0.379824504)) - /* c10 */
MULTIPLY(tmp3, FIX(0.129109289)) - /* c12 */
MULTIPLY(tmp4, FIX(0.608465700)) - /* c8 */
MULTIPLY(tmp5, FIX(0.948429952)), /* c4 */
CONST_BITS+1);
z1 = MULTIPLY(tmp0 - tmp2, FIX(0.875087516)) - /* (c4+c6)/2 */
MULTIPLY(tmp3 - tmp4, FIX(0.330085509)) - /* (c2-c10)/2 */
MULTIPLY(tmp1 - tmp5, FIX(0.239678205)); /* (c8-c12)/2 */
z2 = MULTIPLY(tmp0 + tmp2, FIX(0.073342435)) - /* (c4-c6)/2 */
MULTIPLY(tmp3 + tmp4, FIX(0.709910013)) + /* (c2+c10)/2 */
MULTIPLY(tmp1 + tmp5, FIX(0.368787494)); /* (c8+c12)/2 */
dataptr[DCTSIZE*4] = (DCTELEM) DESCALE(z1 + z2, CONST_BITS+1);
dataptr[DCTSIZE*6] = (DCTELEM) DESCALE(z1 - z2, CONST_BITS+1);
/* Odd part */
tmp1 = MULTIPLY(tmp10 + tmp11, FIX(1.001514908)); /* c3 */
tmp2 = MULTIPLY(tmp10 + tmp12, FIX(0.881514751)); /* c5 */
tmp3 = MULTIPLY(tmp10 + tmp13, FIX(0.710284161)) + /* c7 */
MULTIPLY(tmp14 + tmp15, FIX(0.256335874)); /* c11 */
tmp0 = tmp1 + tmp2 + tmp3 -
MULTIPLY(tmp10, FIX(1.530003162)) + /* c3+c5+c7-c1 */
MULTIPLY(tmp14, FIX(0.241438564)); /* c9-c11 */
tmp4 = MULTIPLY(tmp14 - tmp15, FIX(0.710284161)) - /* c7 */
MULTIPLY(tmp11 + tmp12, FIX(0.256335874)); /* c11 */
tmp5 = MULTIPLY(tmp11 + tmp13, - FIX(0.881514751)); /* -c5 */
tmp1 += tmp4 + tmp5 +
MULTIPLY(tmp11, FIX(0.634110155)) - /* c5+c9+c11-c3 */
MULTIPLY(tmp14, FIX(1.773594819)); /* c1+c7 */
tmp6 = MULTIPLY(tmp12 + tmp13, - FIX(0.497774438)); /* -c9 */
tmp2 += tmp4 + tmp6 -
MULTIPLY(tmp12, FIX(1.190715098)) + /* c1+c5-c9-c11 */
MULTIPLY(tmp15, FIX(1.711799069)); /* c3+c7 */
tmp3 += tmp5 + tmp6 +
MULTIPLY(tmp13, FIX(1.670519935)) - /* c3+c5+c9-c7 */
MULTIPLY(tmp15, FIX(1.319646532)); /* c1+c11 */
dataptr[DCTSIZE*1] = (DCTELEM) DESCALE(tmp0, CONST_BITS+1);
dataptr[DCTSIZE*3] = (DCTELEM) DESCALE(tmp1, CONST_BITS+1);
dataptr[DCTSIZE*5] = (DCTELEM) DESCALE(tmp2, CONST_BITS+1);
dataptr[DCTSIZE*7] = (DCTELEM) DESCALE(tmp3, CONST_BITS+1);
dataptr++; /* advance pointer to next column */
wsptr++; /* advance pointer to next column */
}
}
/*
* Perform the forward DCT on a 14x14 sample block.
*/
GLOBAL(void)
jpeg_fdct_14x14 (DCTELEM * data, JSAMPARRAY sample_data, JDIMENSION start_col)
{
INT32 tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6;
INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15, tmp16;
DCTELEM workspace[8*6];
DCTELEM *dataptr;
DCTELEM *wsptr;
JSAMPROW elemptr;
int ctr;
SHIFT_TEMPS
/* Pass 1: process rows.
* Note results are scaled up by sqrt(8) compared to a true DCT.
* cK represents sqrt(2) * cos(K*pi/28).
*/
dataptr = data;
ctr = 0;
for (;;) {
elemptr = sample_data[ctr] + start_col;
/* Even part */
tmp0 = GETJSAMPLE(elemptr[0]) + GETJSAMPLE(elemptr[13]);
tmp1 = GETJSAMPLE(elemptr[1]) + GETJSAMPLE(elemptr[12]);
tmp2 = GETJSAMPLE(elemptr[2]) + GETJSAMPLE(elemptr[11]);
tmp13 = GETJSAMPLE(elemptr[3]) + GETJSAMPLE(elemptr[10]);
tmp4 = GETJSAMPLE(elemptr[4]) + GETJSAMPLE(elemptr[9]);
tmp5 = GETJSAMPLE(elemptr[5]) + GETJSAMPLE(elemptr[8]);
tmp6 = GETJSAMPLE(elemptr[6]) + GETJSAMPLE(elemptr[7]);
src/Source/LibJPEG/jfdctint.c view on Meta::CPAN
/* Pass 2: process columns.
* We leave the results scaled up by an overall factor of 8.
* We must also scale the output by (8/15)**2 = 64/225, which we partially
* fold into the constant multipliers and final shifting:
* cK now represents sqrt(2) * cos(K*pi/30) * 256/225.
*/
dataptr = data;
wsptr = workspace;
for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
/* Even part */
tmp0 = dataptr[DCTSIZE*0] + wsptr[DCTSIZE*6];
tmp1 = dataptr[DCTSIZE*1] + wsptr[DCTSIZE*5];
tmp2 = dataptr[DCTSIZE*2] + wsptr[DCTSIZE*4];
tmp3 = dataptr[DCTSIZE*3] + wsptr[DCTSIZE*3];
tmp4 = dataptr[DCTSIZE*4] + wsptr[DCTSIZE*2];
tmp5 = dataptr[DCTSIZE*5] + wsptr[DCTSIZE*1];
tmp6 = dataptr[DCTSIZE*6] + wsptr[DCTSIZE*0];
tmp7 = dataptr[DCTSIZE*7];
tmp10 = dataptr[DCTSIZE*0] - wsptr[DCTSIZE*6];
tmp11 = dataptr[DCTSIZE*1] - wsptr[DCTSIZE*5];
tmp12 = dataptr[DCTSIZE*2] - wsptr[DCTSIZE*4];
tmp13 = dataptr[DCTSIZE*3] - wsptr[DCTSIZE*3];
tmp14 = dataptr[DCTSIZE*4] - wsptr[DCTSIZE*2];
tmp15 = dataptr[DCTSIZE*5] - wsptr[DCTSIZE*1];
tmp16 = dataptr[DCTSIZE*6] - wsptr[DCTSIZE*0];
z1 = tmp0 + tmp4 + tmp5;
z2 = tmp1 + tmp3 + tmp6;
z3 = tmp2 + tmp7;
dataptr[DCTSIZE*0] = (DCTELEM)
DESCALE(MULTIPLY(z1 + z2 + z3, FIX(1.137777778)), /* 256/225 */
CONST_BITS+2);
z3 += z3;
dataptr[DCTSIZE*6] = (DCTELEM)
DESCALE(MULTIPLY(z1 - z3, FIX(1.301757503)) - /* c6 */
MULTIPLY(z2 - z3, FIX(0.497227121)), /* c12 */
CONST_BITS+2);
tmp2 += ((tmp1 + tmp4) >> 1) - tmp7 - tmp7;
z1 = MULTIPLY(tmp3 - tmp2, FIX(1.742091575)) - /* c2+c14 */
MULTIPLY(tmp6 - tmp2, FIX(2.546621957)); /* c4+c8 */
z2 = MULTIPLY(tmp5 - tmp2, FIX(0.908479156)) - /* c8-c14 */
MULTIPLY(tmp0 - tmp2, FIX(0.103948774)); /* c2-c4 */
z3 = MULTIPLY(tmp0 - tmp3, FIX(1.573898926)) + /* c2 */
MULTIPLY(tmp6 - tmp5, FIX(1.076671805)) + /* c8 */
MULTIPLY(tmp1 - tmp4, FIX(0.899492312)); /* (c6+c12)/2 */
dataptr[DCTSIZE*2] = (DCTELEM) DESCALE(z1 + z3, CONST_BITS+2);
dataptr[DCTSIZE*4] = (DCTELEM) DESCALE(z2 + z3, CONST_BITS+2);
/* Odd part */
tmp2 = MULTIPLY(tmp10 - tmp12 - tmp13 + tmp15 + tmp16,
FIX(1.393487498)); /* c5 */
tmp1 = MULTIPLY(tmp10 - tmp14 - tmp15, FIX(1.530307725)) + /* c3 */
MULTIPLY(tmp11 - tmp13 - tmp16, FIX(0.945782187)); /* c9 */
tmp12 = MULTIPLY(tmp12, FIX(1.393487498)); /* c5 */
tmp4 = MULTIPLY(tmp10 - tmp16, FIX(1.600246161)) + /* c1 */
MULTIPLY(tmp11 + tmp14, FIX(1.530307725)) + /* c3 */
MULTIPLY(tmp13 + tmp15, FIX(0.654463974)); /* c11 */
tmp0 = MULTIPLY(tmp13, FIX(0.541301207)) - /* c7-c11 */
MULTIPLY(tmp14, FIX(0.584525538)) + /* c3-c9 */
MULTIPLY(tmp16, FIX(1.934788705)) + tmp4 + tmp12; /* c1+c13 */
tmp3 = MULTIPLY(tmp10, - FIX(0.404480980)) - /* -(c1-c7) */
MULTIPLY(tmp11, FIX(2.476089912)) - /* c3+c9 */
MULTIPLY(tmp15, FIX(0.989006518)) + tmp4 - tmp12; /* c11+c13 */
dataptr[DCTSIZE*1] = (DCTELEM) DESCALE(tmp0, CONST_BITS+2);
dataptr[DCTSIZE*3] = (DCTELEM) DESCALE(tmp1, CONST_BITS+2);
dataptr[DCTSIZE*5] = (DCTELEM) DESCALE(tmp2, CONST_BITS+2);
dataptr[DCTSIZE*7] = (DCTELEM) DESCALE(tmp3, CONST_BITS+2);
dataptr++; /* advance pointer to next column */
wsptr++; /* advance pointer to next column */
}
}
/*
* Perform the forward DCT on a 16x16 sample block.
*/
GLOBAL(void)
jpeg_fdct_16x16 (DCTELEM * data, JSAMPARRAY sample_data, JDIMENSION start_col)
{
INT32 tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15, tmp16, tmp17;
DCTELEM workspace[DCTSIZE2];
DCTELEM *dataptr;
DCTELEM *wsptr;
JSAMPROW elemptr;
int ctr;
SHIFT_TEMPS
/* Pass 1: process rows.
* Note results are scaled up by sqrt(8) compared to a true DCT;
* furthermore, we scale the results by 2**PASS1_BITS.
* cK represents sqrt(2) * cos(K*pi/32).
*/
dataptr = data;
ctr = 0;
for (;;) {
elemptr = sample_data[ctr] + start_col;
/* Even part */
tmp0 = GETJSAMPLE(elemptr[0]) + GETJSAMPLE(elemptr[15]);
tmp1 = GETJSAMPLE(elemptr[1]) + GETJSAMPLE(elemptr[14]);
tmp2 = GETJSAMPLE(elemptr[2]) + GETJSAMPLE(elemptr[13]);
tmp3 = GETJSAMPLE(elemptr[3]) + GETJSAMPLE(elemptr[12]);
tmp4 = GETJSAMPLE(elemptr[4]) + GETJSAMPLE(elemptr[11]);
tmp5 = GETJSAMPLE(elemptr[5]) + GETJSAMPLE(elemptr[10]);
tmp6 = GETJSAMPLE(elemptr[6]) + GETJSAMPLE(elemptr[9]);
tmp7 = GETJSAMPLE(elemptr[7]) + GETJSAMPLE(elemptr[8]);
tmp10 = tmp0 + tmp7;
tmp14 = tmp0 - tmp7;
tmp11 = tmp1 + tmp6;
tmp15 = tmp1 - tmp6;
tmp12 = tmp2 + tmp5;
tmp16 = tmp2 - tmp5;
tmp13 = tmp3 + tmp4;
tmp17 = tmp3 - tmp4;
tmp0 = GETJSAMPLE(elemptr[0]) - GETJSAMPLE(elemptr[15]);
tmp1 = GETJSAMPLE(elemptr[1]) - GETJSAMPLE(elemptr[14]);
tmp2 = GETJSAMPLE(elemptr[2]) - GETJSAMPLE(elemptr[13]);
tmp3 = GETJSAMPLE(elemptr[3]) - GETJSAMPLE(elemptr[12]);
tmp4 = GETJSAMPLE(elemptr[4]) - GETJSAMPLE(elemptr[11]);
tmp5 = GETJSAMPLE(elemptr[5]) - GETJSAMPLE(elemptr[10]);
tmp6 = GETJSAMPLE(elemptr[6]) - GETJSAMPLE(elemptr[9]);
tmp7 = GETJSAMPLE(elemptr[7]) - GETJSAMPLE(elemptr[8]);
/* Apply unsigned->signed conversion */
dataptr[0] = (DCTELEM)
((tmp10 + tmp11 + tmp12 + tmp13 - 16 * CENTERJSAMPLE) << PASS1_BITS);
dataptr[4] = (DCTELEM)
DESCALE(MULTIPLY(tmp10 - tmp13, FIX(1.306562965)) + /* c4[16] = c2[8] */
MULTIPLY(tmp11 - tmp12, FIX_0_541196100), /* c12[16] = c6[8] */
CONST_BITS-PASS1_BITS);
tmp10 = MULTIPLY(tmp17 - tmp15, FIX(0.275899379)) + /* c14[16] = c7[8] */
MULTIPLY(tmp14 - tmp16, FIX(1.387039845)); /* c2[16] = c1[8] */
dataptr[2] = (DCTELEM)
DESCALE(tmp10 + MULTIPLY(tmp15, FIX(1.451774982)) /* c6+c14 */
+ MULTIPLY(tmp16, FIX(2.172734804)), /* c2+c10 */
CONST_BITS-PASS1_BITS);
dataptr[6] = (DCTELEM)
DESCALE(tmp10 - MULTIPLY(tmp14, FIX(0.211164243)) /* c2-c6 */
- MULTIPLY(tmp17, FIX(1.061594338)), /* c10+c14 */
CONST_BITS-PASS1_BITS);
/* Odd part */
tmp11 = MULTIPLY(tmp0 + tmp1, FIX(1.353318001)) + /* c3 */
MULTIPLY(tmp6 - tmp7, FIX(0.410524528)); /* c13 */
tmp12 = MULTIPLY(tmp0 + tmp2, FIX(1.247225013)) + /* c5 */
MULTIPLY(tmp5 + tmp7, FIX(0.666655658)); /* c11 */
tmp13 = MULTIPLY(tmp0 + tmp3, FIX(1.093201867)) + /* c7 */
MULTIPLY(tmp4 - tmp7, FIX(0.897167586)); /* c9 */
tmp14 = MULTIPLY(tmp1 + tmp2, FIX(0.138617169)) + /* c15 */
MULTIPLY(tmp6 - tmp5, FIX(1.407403738)); /* c1 */
tmp15 = MULTIPLY(tmp1 + tmp3, - FIX(0.666655658)) + /* -c11 */
MULTIPLY(tmp4 + tmp6, - FIX(1.247225013)); /* -c5 */
tmp16 = MULTIPLY(tmp2 + tmp3, - FIX(1.353318001)) + /* -c3 */
MULTIPLY(tmp5 - tmp4, FIX(0.410524528)); /* c13 */
tmp10 = tmp11 + tmp12 + tmp13 -
MULTIPLY(tmp0, FIX(2.286341144)) + /* c7+c5+c3-c1 */
MULTIPLY(tmp7, FIX(0.779653625)); /* c15+c13-c11+c9 */
tmp11 += tmp14 + tmp15 + MULTIPLY(tmp1, FIX(0.071888074)) /* c9-c3-c15+c11 */
- MULTIPLY(tmp6, FIX(1.663905119)); /* c7+c13+c1-c5 */
tmp12 += tmp14 + tmp16 - MULTIPLY(tmp2, FIX(1.125726048)) /* c7+c5+c15-c3 */
+ MULTIPLY(tmp5, FIX(1.227391138)); /* c9-c11+c1-c13 */
tmp13 += tmp15 + tmp16 + MULTIPLY(tmp3, FIX(1.065388962)) /* c15+c3+c11-c7 */
+ MULTIPLY(tmp4, FIX(2.167985692)); /* c1+c13+c5-c9 */
dataptr[1] = (DCTELEM) DESCALE(tmp10, CONST_BITS-PASS1_BITS);
dataptr[3] = (DCTELEM) DESCALE(tmp11, CONST_BITS-PASS1_BITS);
dataptr[5] = (DCTELEM) DESCALE(tmp12, CONST_BITS-PASS1_BITS);
dataptr[7] = (DCTELEM) DESCALE(tmp13, CONST_BITS-PASS1_BITS);
ctr++;
if (ctr != DCTSIZE) {
if (ctr == DCTSIZE * 2)
break; /* Done. */
dataptr += DCTSIZE; /* advance pointer to next row */
} else
dataptr = workspace; /* switch pointer to extended workspace */
}
/* Pass 2: process columns.
* We remove the PASS1_BITS scaling, but leave the results scaled up
* by an overall factor of 8.
* We must also scale the output by (8/16)**2 = 1/2**2.
* cK represents sqrt(2) * cos(K*pi/32).
*/
dataptr = data;
wsptr = workspace;
for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
/* Even part */
tmp0 = dataptr[DCTSIZE*0] + wsptr[DCTSIZE*7];
tmp1 = dataptr[DCTSIZE*1] + wsptr[DCTSIZE*6];
tmp2 = dataptr[DCTSIZE*2] + wsptr[DCTSIZE*5];
tmp3 = dataptr[DCTSIZE*3] + wsptr[DCTSIZE*4];
tmp4 = dataptr[DCTSIZE*4] + wsptr[DCTSIZE*3];
tmp5 = dataptr[DCTSIZE*5] + wsptr[DCTSIZE*2];
tmp6 = dataptr[DCTSIZE*6] + wsptr[DCTSIZE*1];
tmp7 = dataptr[DCTSIZE*7] + wsptr[DCTSIZE*0];
tmp10 = tmp0 + tmp7;
tmp14 = tmp0 - tmp7;
tmp11 = tmp1 + tmp6;
tmp15 = tmp1 - tmp6;
tmp12 = tmp2 + tmp5;
tmp16 = tmp2 - tmp5;
tmp13 = tmp3 + tmp4;
tmp17 = tmp3 - tmp4;
tmp0 = dataptr[DCTSIZE*0] - wsptr[DCTSIZE*7];
tmp1 = dataptr[DCTSIZE*1] - wsptr[DCTSIZE*6];
tmp2 = dataptr[DCTSIZE*2] - wsptr[DCTSIZE*5];
tmp3 = dataptr[DCTSIZE*3] - wsptr[DCTSIZE*4];
tmp4 = dataptr[DCTSIZE*4] - wsptr[DCTSIZE*3];
tmp5 = dataptr[DCTSIZE*5] - wsptr[DCTSIZE*2];
tmp6 = dataptr[DCTSIZE*6] - wsptr[DCTSIZE*1];
tmp7 = dataptr[DCTSIZE*7] - wsptr[DCTSIZE*0];
dataptr[DCTSIZE*0] = (DCTELEM)
DESCALE(tmp10 + tmp11 + tmp12 + tmp13, PASS1_BITS+2);
dataptr[DCTSIZE*4] = (DCTELEM)
DESCALE(MULTIPLY(tmp10 - tmp13, FIX(1.306562965)) + /* c4[16] = c2[8] */
MULTIPLY(tmp11 - tmp12, FIX_0_541196100), /* c12[16] = c6[8] */
CONST_BITS+PASS1_BITS+2);
tmp10 = MULTIPLY(tmp17 - tmp15, FIX(0.275899379)) + /* c14[16] = c7[8] */
MULTIPLY(tmp14 - tmp16, FIX(1.387039845)); /* c2[16] = c1[8] */
dataptr[DCTSIZE*2] = (DCTELEM)
DESCALE(tmp10 + MULTIPLY(tmp15, FIX(1.451774982)) /* c6+c14 */
+ MULTIPLY(tmp16, FIX(2.172734804)), /* c2+10 */
CONST_BITS+PASS1_BITS+2);
dataptr[DCTSIZE*6] = (DCTELEM)
DESCALE(tmp10 - MULTIPLY(tmp14, FIX(0.211164243)) /* c2-c6 */
- MULTIPLY(tmp17, FIX(1.061594338)), /* c10+c14 */
CONST_BITS+PASS1_BITS+2);
/* Odd part */
tmp11 = MULTIPLY(tmp0 + tmp1, FIX(1.353318001)) + /* c3 */
MULTIPLY(tmp6 - tmp7, FIX(0.410524528)); /* c13 */
tmp12 = MULTIPLY(tmp0 + tmp2, FIX(1.247225013)) + /* c5 */
MULTIPLY(tmp5 + tmp7, FIX(0.666655658)); /* c11 */
tmp13 = MULTIPLY(tmp0 + tmp3, FIX(1.093201867)) + /* c7 */
MULTIPLY(tmp4 - tmp7, FIX(0.897167586)); /* c9 */
tmp14 = MULTIPLY(tmp1 + tmp2, FIX(0.138617169)) + /* c15 */
MULTIPLY(tmp6 - tmp5, FIX(1.407403738)); /* c1 */
tmp15 = MULTIPLY(tmp1 + tmp3, - FIX(0.666655658)) + /* -c11 */
MULTIPLY(tmp4 + tmp6, - FIX(1.247225013)); /* -c5 */
tmp16 = MULTIPLY(tmp2 + tmp3, - FIX(1.353318001)) + /* -c3 */
MULTIPLY(tmp5 - tmp4, FIX(0.410524528)); /* c13 */
tmp10 = tmp11 + tmp12 + tmp13 -
MULTIPLY(tmp0, FIX(2.286341144)) + /* c7+c5+c3-c1 */
MULTIPLY(tmp7, FIX(0.779653625)); /* c15+c13-c11+c9 */
tmp11 += tmp14 + tmp15 + MULTIPLY(tmp1, FIX(0.071888074)) /* c9-c3-c15+c11 */
- MULTIPLY(tmp6, FIX(1.663905119)); /* c7+c13+c1-c5 */
tmp12 += tmp14 + tmp16 - MULTIPLY(tmp2, FIX(1.125726048)) /* c7+c5+c15-c3 */
+ MULTIPLY(tmp5, FIX(1.227391138)); /* c9-c11+c1-c13 */
tmp13 += tmp15 + tmp16 + MULTIPLY(tmp3, FIX(1.065388962)) /* c15+c3+c11-c7 */
+ MULTIPLY(tmp4, FIX(2.167985692)); /* c1+c13+c5-c9 */
dataptr[DCTSIZE*1] = (DCTELEM) DESCALE(tmp10, CONST_BITS+PASS1_BITS+2);
dataptr[DCTSIZE*3] = (DCTELEM) DESCALE(tmp11, CONST_BITS+PASS1_BITS+2);
dataptr[DCTSIZE*5] = (DCTELEM) DESCALE(tmp12, CONST_BITS+PASS1_BITS+2);
dataptr[DCTSIZE*7] = (DCTELEM) DESCALE(tmp13, CONST_BITS+PASS1_BITS+2);
dataptr++; /* advance pointer to next column */
wsptr++; /* advance pointer to next column */
}
}
/*
* Perform the forward DCT on a 16x8 sample block.
*
* 16-point FDCT in pass 1 (rows), 8-point in pass 2 (columns).
*/
GLOBAL(void)
jpeg_fdct_16x8 (DCTELEM * data, JSAMPARRAY sample_data, JDIMENSION start_col)
{
INT32 tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15, tmp16, tmp17;
INT32 z1;
DCTELEM *dataptr;
JSAMPROW elemptr;
int ctr;
SHIFT_TEMPS
/* Pass 1: process rows.
* Note results are scaled up by sqrt(8) compared to a true DCT;
* furthermore, we scale the results by 2**PASS1_BITS.
* 16-point FDCT kernel, cK represents sqrt(2) * cos(K*pi/32).
*/
dataptr = data;
ctr = 0;
for (ctr = 0; ctr < DCTSIZE; ctr++) {
elemptr = sample_data[ctr] + start_col;
/* Even part */
tmp0 = GETJSAMPLE(elemptr[0]) + GETJSAMPLE(elemptr[15]);
tmp1 = GETJSAMPLE(elemptr[1]) + GETJSAMPLE(elemptr[14]);
tmp2 = GETJSAMPLE(elemptr[2]) + GETJSAMPLE(elemptr[13]);
tmp3 = GETJSAMPLE(elemptr[3]) + GETJSAMPLE(elemptr[12]);
tmp4 = GETJSAMPLE(elemptr[4]) + GETJSAMPLE(elemptr[11]);
tmp5 = GETJSAMPLE(elemptr[5]) + GETJSAMPLE(elemptr[10]);
tmp6 = GETJSAMPLE(elemptr[6]) + GETJSAMPLE(elemptr[9]);
tmp7 = GETJSAMPLE(elemptr[7]) + GETJSAMPLE(elemptr[8]);
tmp10 = tmp0 + tmp7;
tmp14 = tmp0 - tmp7;
tmp11 = tmp1 + tmp6;
tmp15 = tmp1 - tmp6;
tmp12 = tmp2 + tmp5;
tmp16 = tmp2 - tmp5;
tmp13 = tmp3 + tmp4;
tmp17 = tmp3 - tmp4;
tmp0 = GETJSAMPLE(elemptr[0]) - GETJSAMPLE(elemptr[15]);
tmp1 = GETJSAMPLE(elemptr[1]) - GETJSAMPLE(elemptr[14]);
tmp2 = GETJSAMPLE(elemptr[2]) - GETJSAMPLE(elemptr[13]);
tmp3 = GETJSAMPLE(elemptr[3]) - GETJSAMPLE(elemptr[12]);
tmp4 = GETJSAMPLE(elemptr[4]) - GETJSAMPLE(elemptr[11]);
tmp5 = GETJSAMPLE(elemptr[5]) - GETJSAMPLE(elemptr[10]);
tmp6 = GETJSAMPLE(elemptr[6]) - GETJSAMPLE(elemptr[9]);
tmp7 = GETJSAMPLE(elemptr[7]) - GETJSAMPLE(elemptr[8]);
/* Apply unsigned->signed conversion */
dataptr[0] = (DCTELEM)
((tmp10 + tmp11 + tmp12 + tmp13 - 16 * CENTERJSAMPLE) << PASS1_BITS);
dataptr[4] = (DCTELEM)
DESCALE(MULTIPLY(tmp10 - tmp13, FIX(1.306562965)) + /* c4[16] = c2[8] */
MULTIPLY(tmp11 - tmp12, FIX_0_541196100), /* c12[16] = c6[8] */
CONST_BITS-PASS1_BITS);
tmp10 = MULTIPLY(tmp17 - tmp15, FIX(0.275899379)) + /* c14[16] = c7[8] */
MULTIPLY(tmp14 - tmp16, FIX(1.387039845)); /* c2[16] = c1[8] */
dataptr[2] = (DCTELEM)
DESCALE(tmp10 + MULTIPLY(tmp15, FIX(1.451774982)) /* c6+c14 */
+ MULTIPLY(tmp16, FIX(2.172734804)), /* c2+c10 */
CONST_BITS-PASS1_BITS);
dataptr[6] = (DCTELEM)
DESCALE(tmp10 - MULTIPLY(tmp14, FIX(0.211164243)) /* c2-c6 */
- MULTIPLY(tmp17, FIX(1.061594338)), /* c10+c14 */
CONST_BITS-PASS1_BITS);
/* Odd part */
tmp11 = MULTIPLY(tmp0 + tmp1, FIX(1.353318001)) + /* c3 */
MULTIPLY(tmp6 - tmp7, FIX(0.410524528)); /* c13 */
tmp12 = MULTIPLY(tmp0 + tmp2, FIX(1.247225013)) + /* c5 */
MULTIPLY(tmp5 + tmp7, FIX(0.666655658)); /* c11 */
tmp13 = MULTIPLY(tmp0 + tmp3, FIX(1.093201867)) + /* c7 */
MULTIPLY(tmp4 - tmp7, FIX(0.897167586)); /* c9 */
tmp14 = MULTIPLY(tmp1 + tmp2, FIX(0.138617169)) + /* c15 */
MULTIPLY(tmp6 - tmp5, FIX(1.407403738)); /* c1 */
tmp15 = MULTIPLY(tmp1 + tmp3, - FIX(0.666655658)) + /* -c11 */
MULTIPLY(tmp4 + tmp6, - FIX(1.247225013)); /* -c5 */
tmp16 = MULTIPLY(tmp2 + tmp3, - FIX(1.353318001)) + /* -c3 */
MULTIPLY(tmp5 - tmp4, FIX(0.410524528)); /* c13 */
tmp10 = tmp11 + tmp12 + tmp13 -
MULTIPLY(tmp0, FIX(2.286341144)) + /* c7+c5+c3-c1 */
MULTIPLY(tmp7, FIX(0.779653625)); /* c15+c13-c11+c9 */
tmp11 += tmp14 + tmp15 + MULTIPLY(tmp1, FIX(0.071888074)) /* c9-c3-c15+c11 */
- MULTIPLY(tmp6, FIX(1.663905119)); /* c7+c13+c1-c5 */
tmp12 += tmp14 + tmp16 - MULTIPLY(tmp2, FIX(1.125726048)) /* c7+c5+c15-c3 */
+ MULTIPLY(tmp5, FIX(1.227391138)); /* c9-c11+c1-c13 */
tmp13 += tmp15 + tmp16 + MULTIPLY(tmp3, FIX(1.065388962)) /* c15+c3+c11-c7 */
+ MULTIPLY(tmp4, FIX(2.167985692)); /* c1+c13+c5-c9 */
dataptr[1] = (DCTELEM) DESCALE(tmp10, CONST_BITS-PASS1_BITS);
dataptr[3] = (DCTELEM) DESCALE(tmp11, CONST_BITS-PASS1_BITS);
dataptr[5] = (DCTELEM) DESCALE(tmp12, CONST_BITS-PASS1_BITS);
dataptr[7] = (DCTELEM) DESCALE(tmp13, CONST_BITS-PASS1_BITS);
dataptr += DCTSIZE; /* advance pointer to next row */
}
/* Pass 2: process columns.
* We remove the PASS1_BITS scaling, but leave the results scaled up
* by an overall factor of 8.
* We must also scale the output by 8/16 = 1/2.
* 8-point FDCT kernel, cK represents sqrt(2) * cos(K*pi/16).
*/
dataptr = data;
for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
/* Even part per LL&M figure 1 --- note that published figure is faulty;
* rotator "c1" should be "c6".
*/
tmp0 = dataptr[DCTSIZE*0] + dataptr[DCTSIZE*7];
tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*6];
tmp2 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*5];
tmp3 = dataptr[DCTSIZE*3] + dataptr[DCTSIZE*4];
tmp10 = tmp0 + tmp3;
tmp12 = tmp0 - tmp3;
tmp11 = tmp1 + tmp2;
tmp13 = tmp1 - tmp2;
tmp0 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*7];
tmp1 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*6];
tmp2 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*5];
tmp3 = dataptr[DCTSIZE*3] - dataptr[DCTSIZE*4];
dataptr[DCTSIZE*0] = (DCTELEM) DESCALE(tmp10 + tmp11, PASS1_BITS+1);
dataptr[DCTSIZE*4] = (DCTELEM) DESCALE(tmp10 - tmp11, PASS1_BITS+1);
z1 = MULTIPLY(tmp12 + tmp13, FIX_0_541196100); /* c6 */
dataptr[DCTSIZE*2] = (DCTELEM)
DESCALE(z1 + MULTIPLY(tmp12, FIX_0_765366865), /* c2-c6 */
CONST_BITS+PASS1_BITS+1);
dataptr[DCTSIZE*6] = (DCTELEM)
DESCALE(z1 - MULTIPLY(tmp13, FIX_1_847759065), /* c2+c6 */
CONST_BITS+PASS1_BITS+1);
/* Odd part per figure 8 --- note paper omits factor of sqrt(2).
* i0..i3 in the paper are tmp0..tmp3 here.
*/
src/Source/LibJPEG/jfdctint.c view on Meta::CPAN
CONST_BITS-PASS1_BITS);
tmp12 = MULTIPLY(tmp0 + tmp1, FIX(1.334852607)) + /* c3 */
MULTIPLY(tmp5 - tmp6, FIX(0.467085129)); /* c11 */
dataptr[3] = (DCTELEM)
DESCALE(tmp10 + tmp12 - MULTIPLY(tmp1, FIX(0.424103948)) /* c3-c9-c13 */
- MULTIPLY(tmp5, FIX(3.069855259)), /* c1+c5+c11 */
CONST_BITS-PASS1_BITS);
dataptr[1] = (DCTELEM)
DESCALE(tmp11 + tmp12 + tmp3 + tmp6 -
MULTIPLY(tmp0 + tmp6, FIX(1.126980169)), /* c3+c5-c1 */
CONST_BITS-PASS1_BITS);
dataptr += DCTSIZE; /* advance pointer to next row */
}
/* Pass 2: process columns.
* We remove the PASS1_BITS scaling, but leave the results scaled up
* by an overall factor of 8.
* We must also scale the output by (8/14)*(8/7) = 32/49, which we
* partially fold into the constant multipliers and final shifting:
* 7-point FDCT kernel, cK represents sqrt(2) * cos(K*pi/14) * 64/49.
*/
dataptr = data;
for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
/* Even part */
tmp0 = dataptr[DCTSIZE*0] + dataptr[DCTSIZE*6];
tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*5];
tmp2 = dataptr[DCTSIZE*2] + dataptr[DCTSIZE*4];
tmp3 = dataptr[DCTSIZE*3];
tmp10 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*6];
tmp11 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*5];
tmp12 = dataptr[DCTSIZE*2] - dataptr[DCTSIZE*4];
z1 = tmp0 + tmp2;
dataptr[DCTSIZE*0] = (DCTELEM)
DESCALE(MULTIPLY(z1 + tmp1 + tmp3, FIX(1.306122449)), /* 64/49 */
CONST_BITS+PASS1_BITS+1);
tmp3 += tmp3;
z1 -= tmp3;
z1 -= tmp3;
z1 = MULTIPLY(z1, FIX(0.461784020)); /* (c2+c6-c4)/2 */
z2 = MULTIPLY(tmp0 - tmp2, FIX(1.202428084)); /* (c2+c4-c6)/2 */
z3 = MULTIPLY(tmp1 - tmp2, FIX(0.411026446)); /* c6 */
dataptr[DCTSIZE*2] = (DCTELEM) DESCALE(z1 + z2 + z3, CONST_BITS+PASS1_BITS+1);
z1 -= z2;
z2 = MULTIPLY(tmp0 - tmp1, FIX(1.151670509)); /* c4 */
dataptr[DCTSIZE*4] = (DCTELEM)
DESCALE(z2 + z3 - MULTIPLY(tmp1 - tmp3, FIX(0.923568041)), /* c2+c6-c4 */
CONST_BITS+PASS1_BITS+1);
dataptr[DCTSIZE*6] = (DCTELEM) DESCALE(z1 + z2, CONST_BITS+PASS1_BITS+1);
/* Odd part */
tmp1 = MULTIPLY(tmp10 + tmp11, FIX(1.221765677)); /* (c3+c1-c5)/2 */
tmp2 = MULTIPLY(tmp10 - tmp11, FIX(0.222383464)); /* (c3+c5-c1)/2 */
tmp0 = tmp1 - tmp2;
tmp1 += tmp2;
tmp2 = MULTIPLY(tmp11 + tmp12, - FIX(1.800824523)); /* -c1 */
tmp1 += tmp2;
tmp3 = MULTIPLY(tmp10 + tmp12, FIX(0.801442310)); /* c5 */
tmp0 += tmp3;
tmp2 += tmp3 + MULTIPLY(tmp12, FIX(2.443531355)); /* c3+c1-c5 */
dataptr[DCTSIZE*1] = (DCTELEM) DESCALE(tmp0, CONST_BITS+PASS1_BITS+1);
dataptr[DCTSIZE*3] = (DCTELEM) DESCALE(tmp1, CONST_BITS+PASS1_BITS+1);
dataptr[DCTSIZE*5] = (DCTELEM) DESCALE(tmp2, CONST_BITS+PASS1_BITS+1);
dataptr++; /* advance pointer to next column */
}
}
/*
* Perform the forward DCT on a 12x6 sample block.
*
* 12-point FDCT in pass 1 (rows), 6-point in pass 2 (columns).
*/
GLOBAL(void)
jpeg_fdct_12x6 (DCTELEM * data, JSAMPARRAY sample_data, JDIMENSION start_col)
{
INT32 tmp0, tmp1, tmp2, tmp3, tmp4, tmp5;
INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15;
DCTELEM *dataptr;
JSAMPROW elemptr;
int ctr;
SHIFT_TEMPS
/* Zero 2 bottom rows of output coefficient block. */
MEMZERO(&data[DCTSIZE*6], SIZEOF(DCTELEM) * DCTSIZE * 2);
/* Pass 1: process rows.
* Note results are scaled up by sqrt(8) compared to a true DCT;
* furthermore, we scale the results by 2**PASS1_BITS.
* 12-point FDCT kernel, cK represents sqrt(2) * cos(K*pi/24).
*/
dataptr = data;
for (ctr = 0; ctr < 6; ctr++) {
elemptr = sample_data[ctr] + start_col;
/* Even part */
tmp0 = GETJSAMPLE(elemptr[0]) + GETJSAMPLE(elemptr[11]);
tmp1 = GETJSAMPLE(elemptr[1]) + GETJSAMPLE(elemptr[10]);
tmp2 = GETJSAMPLE(elemptr[2]) + GETJSAMPLE(elemptr[9]);
tmp3 = GETJSAMPLE(elemptr[3]) + GETJSAMPLE(elemptr[8]);
tmp4 = GETJSAMPLE(elemptr[4]) + GETJSAMPLE(elemptr[7]);
tmp5 = GETJSAMPLE(elemptr[5]) + GETJSAMPLE(elemptr[6]);
tmp10 = tmp0 + tmp5;
tmp13 = tmp0 - tmp5;
tmp11 = tmp1 + tmp4;
tmp14 = tmp1 - tmp4;
tmp12 = tmp2 + tmp3;
tmp15 = tmp2 - tmp3;
tmp0 = GETJSAMPLE(elemptr[0]) - GETJSAMPLE(elemptr[11]);
src/Source/LibJPEG/jfdctint.c view on Meta::CPAN
DCTELEM *dataptr;
JSAMPROW elemptr;
int ctr;
SHIFT_TEMPS
/* Zero 3 bottom rows of output coefficient block. */
MEMZERO(&data[DCTSIZE*5], SIZEOF(DCTELEM) * DCTSIZE * 3);
/* Pass 1: process rows.
* Note results are scaled up by sqrt(8) compared to a true DCT;
* furthermore, we scale the results by 2**PASS1_BITS.
* 10-point FDCT kernel, cK represents sqrt(2) * cos(K*pi/20).
*/
dataptr = data;
for (ctr = 0; ctr < 5; ctr++) {
elemptr = sample_data[ctr] + start_col;
/* Even part */
tmp0 = GETJSAMPLE(elemptr[0]) + GETJSAMPLE(elemptr[9]);
tmp1 = GETJSAMPLE(elemptr[1]) + GETJSAMPLE(elemptr[8]);
tmp12 = GETJSAMPLE(elemptr[2]) + GETJSAMPLE(elemptr[7]);
tmp3 = GETJSAMPLE(elemptr[3]) + GETJSAMPLE(elemptr[6]);
tmp4 = GETJSAMPLE(elemptr[4]) + GETJSAMPLE(elemptr[5]);
tmp10 = tmp0 + tmp4;
tmp13 = tmp0 - tmp4;
tmp11 = tmp1 + tmp3;
tmp14 = tmp1 - tmp3;
tmp0 = GETJSAMPLE(elemptr[0]) - GETJSAMPLE(elemptr[9]);
tmp1 = GETJSAMPLE(elemptr[1]) - GETJSAMPLE(elemptr[8]);
tmp2 = GETJSAMPLE(elemptr[2]) - GETJSAMPLE(elemptr[7]);
tmp3 = GETJSAMPLE(elemptr[3]) - GETJSAMPLE(elemptr[6]);
tmp4 = GETJSAMPLE(elemptr[4]) - GETJSAMPLE(elemptr[5]);
/* Apply unsigned->signed conversion */
dataptr[0] = (DCTELEM)
((tmp10 + tmp11 + tmp12 - 10 * CENTERJSAMPLE) << PASS1_BITS);
tmp12 += tmp12;
dataptr[4] = (DCTELEM)
DESCALE(MULTIPLY(tmp10 - tmp12, FIX(1.144122806)) - /* c4 */
MULTIPLY(tmp11 - tmp12, FIX(0.437016024)), /* c8 */
CONST_BITS-PASS1_BITS);
tmp10 = MULTIPLY(tmp13 + tmp14, FIX(0.831253876)); /* c6 */
dataptr[2] = (DCTELEM)
DESCALE(tmp10 + MULTIPLY(tmp13, FIX(0.513743148)), /* c2-c6 */
CONST_BITS-PASS1_BITS);
dataptr[6] = (DCTELEM)
DESCALE(tmp10 - MULTIPLY(tmp14, FIX(2.176250899)), /* c2+c6 */
CONST_BITS-PASS1_BITS);
/* Odd part */
tmp10 = tmp0 + tmp4;
tmp11 = tmp1 - tmp3;
dataptr[5] = (DCTELEM) ((tmp10 - tmp11 - tmp2) << PASS1_BITS);
tmp2 <<= CONST_BITS;
dataptr[1] = (DCTELEM)
DESCALE(MULTIPLY(tmp0, FIX(1.396802247)) + /* c1 */
MULTIPLY(tmp1, FIX(1.260073511)) + tmp2 + /* c3 */
MULTIPLY(tmp3, FIX(0.642039522)) + /* c7 */
MULTIPLY(tmp4, FIX(0.221231742)), /* c9 */
CONST_BITS-PASS1_BITS);
tmp12 = MULTIPLY(tmp0 - tmp4, FIX(0.951056516)) - /* (c3+c7)/2 */
MULTIPLY(tmp1 + tmp3, FIX(0.587785252)); /* (c1-c9)/2 */
tmp13 = MULTIPLY(tmp10 + tmp11, FIX(0.309016994)) + /* (c3-c7)/2 */
(tmp11 << (CONST_BITS - 1)) - tmp2;
dataptr[3] = (DCTELEM) DESCALE(tmp12 + tmp13, CONST_BITS-PASS1_BITS);
dataptr[7] = (DCTELEM) DESCALE(tmp12 - tmp13, CONST_BITS-PASS1_BITS);
dataptr += DCTSIZE; /* advance pointer to next row */
}
/* Pass 2: process columns.
* We remove the PASS1_BITS scaling, but leave the results scaled up
* by an overall factor of 8.
* We must also scale the output by (8/10)*(8/5) = 32/25, which we
* fold into the constant multipliers:
* 5-point FDCT kernel, cK represents sqrt(2) * cos(K*pi/10) * 32/25.
*/
dataptr = data;
for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
/* Even part */
tmp0 = dataptr[DCTSIZE*0] + dataptr[DCTSIZE*4];
tmp1 = dataptr[DCTSIZE*1] + dataptr[DCTSIZE*3];
tmp2 = dataptr[DCTSIZE*2];
tmp10 = tmp0 + tmp1;
tmp11 = tmp0 - tmp1;
tmp0 = dataptr[DCTSIZE*0] - dataptr[DCTSIZE*4];
tmp1 = dataptr[DCTSIZE*1] - dataptr[DCTSIZE*3];
dataptr[DCTSIZE*0] = (DCTELEM)
DESCALE(MULTIPLY(tmp10 + tmp2, FIX(1.28)), /* 32/25 */
CONST_BITS+PASS1_BITS);
tmp11 = MULTIPLY(tmp11, FIX(1.011928851)); /* (c2+c4)/2 */
tmp10 -= tmp2 << 2;
tmp10 = MULTIPLY(tmp10, FIX(0.452548340)); /* (c2-c4)/2 */
dataptr[DCTSIZE*2] = (DCTELEM) DESCALE(tmp11 + tmp10, CONST_BITS+PASS1_BITS);
dataptr[DCTSIZE*4] = (DCTELEM) DESCALE(tmp11 - tmp10, CONST_BITS+PASS1_BITS);
/* Odd part */
tmp10 = MULTIPLY(tmp0 + tmp1, FIX(1.064004961)); /* c3 */
dataptr[DCTSIZE*1] = (DCTELEM)
DESCALE(tmp10 + MULTIPLY(tmp0, FIX(0.657591230)), /* c1-c3 */
CONST_BITS+PASS1_BITS);
dataptr[DCTSIZE*3] = (DCTELEM)
DESCALE(tmp10 - MULTIPLY(tmp1, FIX(2.785601151)), /* c1+c3 */
CONST_BITS+PASS1_BITS);
dataptr++; /* advance pointer to next column */
}
}
src/Source/LibJPEG/jfdctint.c view on Meta::CPAN
* We remove the PASS1_BITS scaling, but leave the results scaled up
* by an overall factor of 8.
* We must also scale the output by 8/16 = 1/2.
* 16-point FDCT kernel, cK represents sqrt(2) * cos(K*pi/32).
*/
dataptr = data;
wsptr = workspace;
for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
/* Even part */
tmp0 = dataptr[DCTSIZE*0] + wsptr[DCTSIZE*7];
tmp1 = dataptr[DCTSIZE*1] + wsptr[DCTSIZE*6];
tmp2 = dataptr[DCTSIZE*2] + wsptr[DCTSIZE*5];
tmp3 = dataptr[DCTSIZE*3] + wsptr[DCTSIZE*4];
tmp4 = dataptr[DCTSIZE*4] + wsptr[DCTSIZE*3];
tmp5 = dataptr[DCTSIZE*5] + wsptr[DCTSIZE*2];
tmp6 = dataptr[DCTSIZE*6] + wsptr[DCTSIZE*1];
tmp7 = dataptr[DCTSIZE*7] + wsptr[DCTSIZE*0];
tmp10 = tmp0 + tmp7;
tmp14 = tmp0 - tmp7;
tmp11 = tmp1 + tmp6;
tmp15 = tmp1 - tmp6;
tmp12 = tmp2 + tmp5;
tmp16 = tmp2 - tmp5;
tmp13 = tmp3 + tmp4;
tmp17 = tmp3 - tmp4;
tmp0 = dataptr[DCTSIZE*0] - wsptr[DCTSIZE*7];
tmp1 = dataptr[DCTSIZE*1] - wsptr[DCTSIZE*6];
tmp2 = dataptr[DCTSIZE*2] - wsptr[DCTSIZE*5];
tmp3 = dataptr[DCTSIZE*3] - wsptr[DCTSIZE*4];
tmp4 = dataptr[DCTSIZE*4] - wsptr[DCTSIZE*3];
tmp5 = dataptr[DCTSIZE*5] - wsptr[DCTSIZE*2];
tmp6 = dataptr[DCTSIZE*6] - wsptr[DCTSIZE*1];
tmp7 = dataptr[DCTSIZE*7] - wsptr[DCTSIZE*0];
dataptr[DCTSIZE*0] = (DCTELEM)
DESCALE(tmp10 + tmp11 + tmp12 + tmp13, PASS1_BITS+1);
dataptr[DCTSIZE*4] = (DCTELEM)
DESCALE(MULTIPLY(tmp10 - tmp13, FIX(1.306562965)) + /* c4[16] = c2[8] */
MULTIPLY(tmp11 - tmp12, FIX_0_541196100), /* c12[16] = c6[8] */
CONST_BITS+PASS1_BITS+1);
tmp10 = MULTIPLY(tmp17 - tmp15, FIX(0.275899379)) + /* c14[16] = c7[8] */
MULTIPLY(tmp14 - tmp16, FIX(1.387039845)); /* c2[16] = c1[8] */
dataptr[DCTSIZE*2] = (DCTELEM)
DESCALE(tmp10 + MULTIPLY(tmp15, FIX(1.451774982)) /* c6+c14 */
+ MULTIPLY(tmp16, FIX(2.172734804)), /* c2+c10 */
CONST_BITS+PASS1_BITS+1);
dataptr[DCTSIZE*6] = (DCTELEM)
DESCALE(tmp10 - MULTIPLY(tmp14, FIX(0.211164243)) /* c2-c6 */
- MULTIPLY(tmp17, FIX(1.061594338)), /* c10+c14 */
CONST_BITS+PASS1_BITS+1);
/* Odd part */
tmp11 = MULTIPLY(tmp0 + tmp1, FIX(1.353318001)) + /* c3 */
MULTIPLY(tmp6 - tmp7, FIX(0.410524528)); /* c13 */
tmp12 = MULTIPLY(tmp0 + tmp2, FIX(1.247225013)) + /* c5 */
MULTIPLY(tmp5 + tmp7, FIX(0.666655658)); /* c11 */
tmp13 = MULTIPLY(tmp0 + tmp3, FIX(1.093201867)) + /* c7 */
MULTIPLY(tmp4 - tmp7, FIX(0.897167586)); /* c9 */
tmp14 = MULTIPLY(tmp1 + tmp2, FIX(0.138617169)) + /* c15 */
MULTIPLY(tmp6 - tmp5, FIX(1.407403738)); /* c1 */
tmp15 = MULTIPLY(tmp1 + tmp3, - FIX(0.666655658)) + /* -c11 */
MULTIPLY(tmp4 + tmp6, - FIX(1.247225013)); /* -c5 */
tmp16 = MULTIPLY(tmp2 + tmp3, - FIX(1.353318001)) + /* -c3 */
MULTIPLY(tmp5 - tmp4, FIX(0.410524528)); /* c13 */
tmp10 = tmp11 + tmp12 + tmp13 -
MULTIPLY(tmp0, FIX(2.286341144)) + /* c7+c5+c3-c1 */
MULTIPLY(tmp7, FIX(0.779653625)); /* c15+c13-c11+c9 */
tmp11 += tmp14 + tmp15 + MULTIPLY(tmp1, FIX(0.071888074)) /* c9-c3-c15+c11 */
- MULTIPLY(tmp6, FIX(1.663905119)); /* c7+c13+c1-c5 */
tmp12 += tmp14 + tmp16 - MULTIPLY(tmp2, FIX(1.125726048)) /* c7+c5+c15-c3 */
+ MULTIPLY(tmp5, FIX(1.227391138)); /* c9-c11+c1-c13 */
tmp13 += tmp15 + tmp16 + MULTIPLY(tmp3, FIX(1.065388962)) /* c15+c3+c11-c7 */
+ MULTIPLY(tmp4, FIX(2.167985692)); /* c1+c13+c5-c9 */
dataptr[DCTSIZE*1] = (DCTELEM) DESCALE(tmp10, CONST_BITS+PASS1_BITS+1);
dataptr[DCTSIZE*3] = (DCTELEM) DESCALE(tmp11, CONST_BITS+PASS1_BITS+1);
dataptr[DCTSIZE*5] = (DCTELEM) DESCALE(tmp12, CONST_BITS+PASS1_BITS+1);
dataptr[DCTSIZE*7] = (DCTELEM) DESCALE(tmp13, CONST_BITS+PASS1_BITS+1);
dataptr++; /* advance pointer to next column */
wsptr++; /* advance pointer to next column */
}
}
/*
* Perform the forward DCT on a 7x14 sample block.
*
* 7-point FDCT in pass 1 (rows), 14-point in pass 2 (columns).
*/
GLOBAL(void)
jpeg_fdct_7x14 (DCTELEM * data, JSAMPARRAY sample_data, JDIMENSION start_col)
{
INT32 tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6;
INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15, tmp16;
INT32 z1, z2, z3;
DCTELEM workspace[8*6];
DCTELEM *dataptr;
DCTELEM *wsptr;
JSAMPROW elemptr;
int ctr;
SHIFT_TEMPS
/* Pre-zero output coefficient block. */
MEMZERO(data, SIZEOF(DCTELEM) * DCTSIZE2);
/* Pass 1: process rows.
* Note results are scaled up by sqrt(8) compared to a true DCT;
* furthermore, we scale the results by 2**PASS1_BITS.
* 7-point FDCT kernel, cK represents sqrt(2) * cos(K*pi/14).
*/
dataptr = data;
ctr = 0;
for (;;) {
elemptr = sample_data[ctr] + start_col;
/* Even part */
tmp0 = GETJSAMPLE(elemptr[0]) + GETJSAMPLE(elemptr[6]);
tmp1 = GETJSAMPLE(elemptr[1]) + GETJSAMPLE(elemptr[5]);
tmp2 = GETJSAMPLE(elemptr[2]) + GETJSAMPLE(elemptr[4]);
tmp3 = GETJSAMPLE(elemptr[3]);
( run in 0.483 second using v1.01-cache-2.11-cpan-e93a5daba3e )