jfdctint.c

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  }
}


/*
 * Perform the forward DCT on a 12x12 sample block.
 */

GLOBAL(void)
jpeg_fdct_12x12 (DCTELEM * data, JSAMPARRAY sample_data, JDIMENSION start_col)
{
  INT32 tmp0, tmp1, tmp2, tmp3, tmp4, tmp5;
  INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15;
  DCTELEM workspace[8*4];
  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/24). */

  dataptr = data;
  ctr = 0;
  for (;;) {
    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]);
    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]);

    /* Apply unsigned->signed conversion */
    dataptr[0] = (DCTELEM) (tmp10 + tmp11 + tmp12 - 12 * CENTERJSAMPLE);
    dataptr[6] = (DCTELEM) (tmp13 - tmp14 - tmp15);
    dataptr[4] = (DCTELEM)
      DESCALE(MULTIPLY(tmp10 - tmp12, FIX(1.224744871)), /* c4 */
	      CONST_BITS);
    dataptr[2] = (DCTELEM)
      DESCALE(tmp14 - tmp15 + MULTIPLY(tmp13 + tmp15, FIX(1.366025404)), /* c2 */
	      CONST_BITS);

    /* Odd part */

    tmp10 = MULTIPLY(tmp1 + tmp4, FIX_0_541196100);    /* c9 */
    tmp14 = tmp10 + MULTIPLY(tmp1, FIX_0_765366865);   /* c3-c9 */
    tmp15 = tmp10 - MULTIPLY(tmp4, FIX_1_847759065);   /* c3+c9 */
    tmp12 = MULTIPLY(tmp0 + tmp2, FIX(1.121971054));   /* c5 */
    tmp13 = MULTIPLY(tmp0 + tmp3, FIX(0.860918669));   /* c7 */
    tmp10 = tmp12 + tmp13 + tmp14 - MULTIPLY(tmp0, FIX(0.580774953)) /* c5+c7-c1 */
	    + MULTIPLY(tmp5, FIX(0.184591911));        /* c11 */
    tmp11 = MULTIPLY(tmp2 + tmp3, - FIX(0.184591911)); /* -c11 */
    tmp12 += tmp11 - tmp15 - MULTIPLY(tmp2, FIX(2.339493912)) /* c1+c5-c11 */
	    + MULTIPLY(tmp5, FIX(0.860918669));        /* c7 */
    tmp13 += tmp11 - tmp14 + MULTIPLY(tmp3, FIX(0.725788011)) /* c1+c11-c7 */
	    - MULTIPLY(tmp5, FIX(1.121971054));        /* c5 */
    tmp11 = tmp15 + MULTIPLY(tmp0 - tmp3, FIX(1.306562965)) /* c3 */
	    - MULTIPLY(tmp2 + tmp5, FIX_0_541196100);  /* c9 */

    dataptr[1] = (DCTELEM) DESCALE(tmp10, CONST_BITS);
    dataptr[3] = (DCTELEM) DESCALE(tmp11, CONST_BITS);
    dataptr[5] = (DCTELEM) DESCALE(tmp12, CONST_BITS);
    dataptr[7] = (DCTELEM) DESCALE(tmp13, CONST_BITS);

    ctr++;

    if (ctr != DCTSIZE) {
      if (ctr == 12)
	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 (8/12)**2 = 4/9, which we partially
   * fold into the constant multipliers and final shifting:
   * cK now represents sqrt(2) * cos(K*pi/24) * 8/9.
   */

  dataptr = data;
  wsptr = workspace;
  for (ctr = DCTSIZE-1; ctr >= 0; ctr--) {
    /* Even part */

    tmp0 = dataptr[DCTSIZE*0] + wsptr[DCTSIZE*3];
    tmp1 = dataptr[DCTSIZE*1] + wsptr[DCTSIZE*2];
    tmp2 = dataptr[DCTSIZE*2] + wsptr[DCTSIZE*1];
    tmp3 = dataptr[DCTSIZE*3] + wsptr[DCTSIZE*0];
    tmp4 = dataptr[DCTSIZE*4] + dataptr[DCTSIZE*7];
    tmp5 = dataptr[DCTSIZE*5] + dataptr[DCTSIZE*6];

    tmp10 = tmp0 + tmp5;
    tmp13 = tmp0 - tmp5;
    tmp11 = tmp1 + tmp4;
    tmp14 = tmp1 - tmp4;
    tmp12 = tmp2 + tmp3;
    tmp15 = tmp2 - tmp3;

    tmp0 = dataptr[DCTSIZE*0] - wsptr[DCTSIZE*3];
    tmp1 = dataptr[DCTSIZE*1] - wsptr[DCTSIZE*2];
    tmp2 = dataptr[DCTSIZE*2] - wsptr[DCTSIZE*1];
    tmp3 = dataptr[DCTSIZE*3] - wsptr[DCTSIZE*0];
    tmp4 = dataptr[DCTSIZE*4] - dataptr[DCTSIZE*7];
    tmp5 = dataptr[DCTSIZE*5] - dataptr[DCTSIZE*6];

    dataptr[DCTSIZE*0] = (DCTELEM)
      DESCALE(MULTIPLY(tmp10 + tmp11 + tmp12, FIX(0.888888889)), /* 8/9 */
	      CONST_BITS+1);
    dataptr[DCTSIZE*6] = (DCTELEM)
      DESCALE(MULTIPLY(tmp13 - tmp14 - tmp15, FIX(0.888888889)), /* 8/9 */
	      CONST_BITS+1);
    dataptr[DCTSIZE*4] = (DCTELEM)
      DESCALE(MULTIPLY(tmp10 - tmp12, FIX(1.088662108)),         /* c4 */
	      CONST_BITS+1);
    dataptr[DCTSIZE*2] = (DCTELEM)
      DESCALE(MULTIPLY(tmp14 - tmp15, FIX(0.888888889)) +        /* 8/9 */
	      MULTIPLY(tmp13 + tmp15, FIX(1.214244803)),         /* c2 */
	      CONST_BITS+1);

    /* Odd part */

    tmp10 = MULTIPLY(tmp1 + tmp4, FIX(0.481063200));   /* c9 */
    tmp14 = tmp10 + MULTIPLY(tmp1, FIX(0.680326102));  /* c3-c9 */
    tmp15 = tmp10 - MULTIPLY(tmp4, FIX(1.642452502));  /* c3+c9 */
    tmp12 = MULTIPLY(tmp0 + tmp2, FIX(0.997307603));   /* c5 */
    tmp13 = MULTIPLY(tmp0 + tmp3, FIX(0.765261039));   /* c7 */
    tmp10 = tmp12 + tmp13 + tmp14 - MULTIPLY(tmp0, FIX(0.516244403)) /* c5+c7-c1 */
	    + MULTIPLY(tmp5, FIX(0.164081699));        /* c11 */
    tmp11 = MULTIPLY(tmp2 + tmp3, - FIX(0.164081699)); /* -c11 */
    tmp12 += tmp11 - tmp15 - MULTIPLY(tmp2, FIX(2.079550144)) /* c1+c5-c11 */
	    + MULTIPLY(tmp5, FIX(0.765261039));        /* c7 */
    tmp13 += tmp11 - tmp14 + MULTIPLY(tmp3, FIX(0.645144899)) /* c1+c11-c7 */
	    - MULTIPLY(tmp5, FIX(0.997307603));        /* c5 */
    tmp11 = tmp15 + MULTIPLY(tmp0 - tmp3, FIX(1.161389302)) /* c3 */
	    - MULTIPLY(tmp2 + tmp5, FIX(0.481063200)); /* c9 */

    dataptr[DCTSIZE*1] = (DCTELEM) DESCALE(tmp10, CONST_BITS+1);
    dataptr[DCTSIZE*3] = (DCTELEM) DESCALE(tmp11, CONST_BITS+1);
    dataptr[DCTSIZE*5] = (DCTELEM) DESCALE(tmp12, CONST_BITS+1);
    dataptr[DCTSIZE*7] = (DCTELEM) DESCALE(tmp13, CONST_BITS+1);

    dataptr++;			/* advance pointer to next column */
    wsptr++;			/* advance pointer to next column */
  }
}


/*
 * Perform the forward DCT on a 13x13 sample block.
 */

GLOBAL(void)
jpeg_fdct_13x13 (DCTELEM * data, JSAMPARRAY sample_data, JDIMENSION start_col)
{
  INT32 tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6;
  INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15;
  INT32 z1, z2;
  DCTELEM workspace[8*5];
  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/26). */

  dataptr = data;
  ctr = 0;
  for (;;) {
    elemptr = sample_data[ctr] + start_col;

    /* Even part */

    tmp0 = GETJSAMPLE(elemptr[0]) + GETJSAMPLE(elemptr[12]);
    tmp1 = GETJSAMPLE(elemptr[1]) + GETJSAMPLE(elemptr[11]);
    tmp2 = GETJSAMPLE(elemptr[2]) + GETJSAMPLE(elemptr[10]);
    tmp3 = GETJSAMPLE(elemptr[3]) + GETJSAMPLE(elemptr[9]);
    tmp4 = GETJSAMPLE(elemptr[4]) + GETJSAMPLE(elemptr[8]);
    tmp5 = GETJSAMPLE(elemptr[5]) + GETJSAMPLE(elemptr[7]);
    tmp6 = GETJSAMPLE(elemptr[6]);

    tmp10 = GETJSAMPLE(elemptr[0]) - GETJSAMPLE(elemptr[12]);
    tmp11 = GETJSAMPLE(elemptr[1]) - GETJSAMPLE(elemptr[11]);
    tmp12 = GETJSAMPLE(elemptr[2]) - GETJSAMPLE(elemptr[10]);
    tmp13 = GETJSAMPLE(elemptr[3]) - GETJSAMPLE(elemptr[9]);
    tmp14 = GETJSAMPLE(elemptr[4]) - GETJSAMPLE(elemptr[8]);
    tmp15 = GETJSAMPLE(elemptr[5]) - GETJSAMPLE(elemptr[7]);

    /* Apply unsigned->signed conversion */
    dataptr[0] = (DCTELEM)
      (tmp0 + tmp1 + tmp2 + tmp3 + tmp4 + tmp5 + tmp6 - 13 * CENTERJSAMPLE);
    tmp6 += tmp6;
    tmp0 -= tmp6;
    tmp1 -= tmp6;
    tmp2 -= tmp6;
    tmp3 -= tmp6;
    tmp4 -= tmp6;
    tmp5 -= tmp6;
    dataptr[2] = (DCTELEM)
      DESCALE(MULTIPLY(tmp0, FIX(1.373119086)) +   /* c2 */
	      MULTIPLY(tmp1, FIX(1.058554052)) +   /* c6 */
	      MULTIPLY(tmp2, FIX(0.501487041)) -   /* c10 */
	      MULTIPLY(tmp3, FIX(0.170464608)) -   /* c12 */
	      MULTIPLY(tmp4, FIX(0.803364869)) -   /* c8 */
	      MULTIPLY(tmp5, FIX(1.252223920)),    /* c4 */
	      CONST_BITS);
    z1 = MULTIPLY(tmp0 - tmp2, FIX(1.155388986)) - /* (c4+c6)/2 */
	 MULTIPLY(tmp3 - tmp4, FIX(0.435816023)) - /* (c2-c10)/2 */
	 MULTIPLY(tmp1 - tmp5, FIX(0.316450131));  /* (c8-c12)/2 */
    z2 = MULTIPLY(tmp0 + tmp2, FIX(0.096834934)) - /* (c4-c6)/2 */
	 MULTIPLY(tmp3 + tmp4, FIX(0.937303064)) + /* (c2+c10)/2 */
	 MULTIPLY(tmp1 + tmp5, FIX(0.486914739));  /* (c8+c12)/2 */

    dataptr[4] = (DCTELEM) DESCALE(z1 + z2, CONST_BITS);
    dataptr[6] = (DCTELEM) DESCALE(z1 - z2, CONST_BITS);

    /* Odd part */

    tmp1 = MULTIPLY(tmp10 + tmp11, FIX(1.322312651));   /* c3 */
    tmp2 = MULTIPLY(tmp10 + tmp12, FIX(1.163874945));   /* c5 */
    tmp3 = MULTIPLY(tmp10 + tmp13, FIX(0.937797057)) +  /* c7 */
	   MULTIPLY(tmp14 + tmp15, FIX(0.338443458));   /* c11 */
    tmp0 = tmp1 + tmp2 + tmp3 -
	   MULTIPLY(tmp10, FIX(2.020082300)) +          /* c3+c5+c7-c1 */
	   MULTIPLY(tmp14, FIX(0.318774355));           /* c9-c11 */
    tmp4 = MULTIPLY(tmp14 - tmp15, FIX(0.937797057)) -  /* c7 */
	   MULTIPLY(tmp11 + tmp12, FIX(0.338443458));   /* c11 */
    tmp5 = MULTIPLY(tmp11 + tmp13, - FIX(1.163874945)); /* -c5 */
    tmp1 += tmp4 + tmp5 +
	    MULTIPLY(tmp11, FIX(0.837223564)) -         /* c5+c9+c11-c3 */
	    MULTIPLY(tmp14, FIX(2.341699410));          /* c1+c7 */
    tmp6 = MULTIPLY(tmp12 + tmp13, - FIX(0.657217813)); /* -c9 */
    tmp2 += tmp4 + tmp6 -
	    MULTIPLY(tmp12, FIX(1.572116027)) +         /* c1+c5-c9-c11 */
	    MULTIPLY(tmp15, FIX(2.260109708));          /* c3+c7 */
    tmp3 += tmp5 + tmp6 +
	    MULTIPLY(tmp13, FIX(2.205608352)) -         /* c3+c5+c9-c7 */
	    MULTIPLY(tmp15, FIX(1.742345811));          /* c1+c11 */

    dataptr[1] = (DCTELEM) DESCALE(tmp0, CONST_BITS);
    dataptr[3] = (DCTELEM) DESCALE(tmp1, CONST_BITS);
    dataptr[5] = (DCTELEM) DESCALE(tmp2, CONST_BITS);
    dataptr[7] = (DCTELEM) DESCALE(tmp3, CONST_BITS);

    ctr++;

    if (ctr != DCTSIZE) {
      if (ctr == 13)
	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 (8/13)**2 = 64/169, which we partially
   * fold into the constant multipliers and final shifting:
   * 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 */
	    M