forward_DCT_method_ptr do_dct[MAX_COMPONENTS];

  float_DCT_method_ptr do_float_dct[MAX_COMPONENTS];

/* The current scaled-DCT routines require ISLOW-style divisor tables,

 * so be sure to compile that code if either ISLOW or SCALING is requested.

#define PROVIDE_ISLOW_TABLES

#else

#ifdef DCT_SCALING_SUPPORTED

#define PROVIDE_ISLOW_TABLES

  forward_DCT_method_ptr do_dct = fdct->do_dct[compptr->component_index];

  for (bi = 0; bi < num_blocks; bi++, start_col += compptr->DCT_h_scaled_size) {

    (*do_dct) (workspace, sample_data, start_col);

  float_DCT_method_ptr do_dct = fdct->do_float_dct[compptr->component_index];

  for (bi = 0; bi < num_blocks; bi++, start_col += compptr->DCT_h_scaled_size) {

    (*do_dct) (workspace, sample_data, start_col);

 * Initialize for a processing pass.

 * Verify that all referenced Q-tables are present, and set up

 * the divisor table for each one.

 * In the current implementation, DCT of all components is done during

 * the first pass, even if only some components will be output in the

 * first scan.  Hence all components should be examined here.

 */

METHODDEF(void)

start_pass_fdctmgr (j_compress_ptr cinfo)

{

  my_fdct_ptr fdct = (my_fdct_ptr) cinfo->fdct;

  int ci, qtblno, i;

  jpeg_component_info *compptr;

  int method = 0;

  JQUANT_TBL * qtbl;

  DCTELEM * dtbl;

  for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;

       ci++, compptr++) {

    /* Select the proper DCT routine for this component's scaling */

    switch ((compptr->DCT_h_scaled_size << 8) + compptr->DCT_v_scaled_size) {

#ifdef DCT_SCALING_SUPPORTED

    case ((1 << 8) + 1):

      fdct->do_dct[ci] = jpeg_fdct_1x1;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((2 << 8) + 2):

      fdct->do_dct[ci] = jpeg_fdct_2x2;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((3 << 8) + 3):

      fdct->do_dct[ci] = jpeg_fdct_3x3;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((4 << 8) + 4):

      fdct->do_dct[ci] = jpeg_fdct_4x4;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((5 << 8) + 5):

      fdct->do_dct[ci] = jpeg_fdct_5x5;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((6 << 8) + 6):

      fdct->do_dct[ci] = jpeg_fdct_6x6;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((7 << 8) + 7):

      fdct->do_dct[ci] = jpeg_fdct_7x7;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((9 << 8) + 9):

      fdct->do_dct[ci] = jpeg_fdct_9x9;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((10 << 8) + 10):

      fdct->do_dct[ci] = jpeg_fdct_10x10;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((11 << 8) + 11):

      fdct->do_dct[ci] = jpeg_fdct_11x11;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((12 << 8) + 12):

      fdct->do_dct[ci] = jpeg_fdct_12x12;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((13 << 8) + 13):

      fdct->do_dct[ci] = jpeg_fdct_13x13;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((14 << 8) + 14):

      fdct->do_dct[ci] = jpeg_fdct_14x14;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((15 << 8) + 15):

      fdct->do_dct[ci] = jpeg_fdct_15x15;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((16 << 8) + 16):

      fdct->do_dct[ci] = jpeg_fdct_16x16;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((16 << 8) + 8):

      fdct->do_dct[ci] = jpeg_fdct_16x8;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((14 << 8) + 7):

      fdct->do_dct[ci] = jpeg_fdct_14x7;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((12 << 8) + 6):

      fdct->do_dct[ci] = jpeg_fdct_12x6;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((10 << 8) + 5):

      fdct->do_dct[ci] = jpeg_fdct_10x5;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((8 << 8) + 4):

      fdct->do_dct[ci] = jpeg_fdct_8x4;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((6 << 8) + 3):

      fdct->do_dct[ci] = jpeg_fdct_6x3;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((4 << 8) + 2):

      fdct->do_dct[ci] = jpeg_fdct_4x2;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((2 << 8) + 1):

      fdct->do_dct[ci] = jpeg_fdct_2x1;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((8 << 8) + 16):

      fdct->do_dct[ci] = jpeg_fdct_8x16;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((7 << 8) + 14):

      fdct->do_dct[ci] = jpeg_fdct_7x14;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((6 << 8) + 12):

      fdct->do_dct[ci] = jpeg_fdct_6x12;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((5 << 8) + 10):

      fdct->do_dct[ci] = jpeg_fdct_5x10;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((4 << 8) + 8):

      fdct->do_dct[ci] = jpeg_fdct_4x8;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((3 << 8) + 6):

      fdct->do_dct[ci] = jpeg_fdct_3x6;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((2 << 8) + 4):

      fdct->do_dct[ci] = jpeg_fdct_2x4;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

    case ((1 << 8) + 2):

      fdct->do_dct[ci] = jpeg_fdct_1x2;

      method = JDCT_ISLOW;	/* jfdctint uses islow-style table */

      break;

#endif

    case ((DCTSIZE << 8) + DCTSIZE):

      switch (cinfo->dct_method) {

#ifdef DCT_ISLOW_SUPPORTED

      case JDCT_ISLOW:

	fdct->do_dct[ci] = jpeg_fdct_islow;

	method = JDCT_ISLOW;

	break;

#endif

#ifdef DCT_IFAST_SUPPORTED

      case JDCT_IFAST:

	fdct->do_dct[ci] = jpeg_fdct_ifast;

	method = JDCT_IFAST;

	break;

#endif

#ifdef DCT_FLOAT_SUPPORTED

      case JDCT_FLOAT:

	fdct->do_float_dct[ci] = jpeg_fdct_float;

	method = JDCT_FLOAT;

	break;

#endif

      default:

	ERREXIT(cinfo, JERR_NOT_COMPILED);

	break;

      }

      break;

    default:

      ERREXIT2(cinfo, JERR_BAD_DCTSIZE,

	       compptr->DCT_h_scaled_size, compptr->DCT_v_scaled_size);

      break;

    }

    qtblno = compptr->quant_tbl_no;

    /* Make sure specified quantization table is present */

    if (qtblno < 0 || qtblno >= NUM_QUANT_TBLS ||

	cinfo->quant_tbl_ptrs[qtblno] == NULL)

      ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, qtblno);

    qtbl = cinfo->quant_tbl_ptrs[qtblno];

    /* Compute divisors for this quant table */

    /* We may do this more than once for same table, but it's not a big deal */

    switch (method) {

#ifdef PROVIDE_ISLOW_TABLES

    case JDCT_ISLOW:

      /* For LL&M IDCT method, divisors are equal to raw quantization

       * coefficients multiplied by 8 (to counteract scaling).

       */

      if (fdct->divisors[qtblno] == NULL) {

	fdct->divisors[qtblno] = (DCTELEM *)

	  (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

				      DCTSIZE2 * SIZEOF(DCTELEM));

      }

      dtbl = fdct->divisors[qtblno];

      for (i = 0; i < DCTSIZE2; i++) {

	dtbl[i] = ((DCTELEM) qtbl->quantval[i]) << 3;

      }

      fdct->pub.forward_DCT[ci] = forward_DCT;

      break;

#endif

#ifdef DCT_IFAST_SUPPORTED

    case JDCT_IFAST:

      {

	/* For AA&N IDCT method, divisors are equal to quantization

	 * coefficients scaled by scalefactor[row]*scalefactor[col], where

	 *   scalefactor[0] = 1

	 *   scalefactor[k] = cos(k*PI/16) * sqrt(2)    for k=1..7

	 * We apply a further scale factor of 8.

	 */

#define CONST_BITS 14

	static const INT16 aanscales[DCTSIZE2] = {

	  /* precomputed values scaled up by 14 bits */

	  16384, 22725, 21407, 19266, 16384, 12873,  8867,  4520,

	  22725, 31521, 29692, 26722, 22725, 17855, 12299,  6270,

	  21407, 29692, 27969, 25172, 21407, 16819, 11585,  5906,

	  19266, 26722, 25172, 22654, 19266, 15137, 10426,  5315,

	  16384, 22725, 21407, 19266, 16384, 12873,  8867,  4520,

	  12873, 17855, 16819, 15137, 12873, 10114,  6967,  3552,

	   8867, 12299, 11585, 10426,  8867,  6967,  4799,  2446,

	   4520,  6270,  5906,  5315,  4520,  3552,  2446,  1247

	};

	SHIFT_TEMPS

	if (fdct->divisors[qtblno] == NULL) {

	  fdct->divisors[qtblno] = (DCTELEM *)

	    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

					DCTSIZE2 * SIZEOF(DCTELEM));

	}

	dtbl = fdct->divisors[qtblno];

	for (i = 0; i < DCTSIZE2; i++) {

	  dtbl[i] = (DCTELEM)

	    DESCALE(MULTIPLY16V16((INT32) qtbl->quantval[i],

				  (INT32) aanscales[i]),

		    CONST_BITS-3);

	}

      }

      fdct->pub.forward_DCT[ci] = forward_DCT;

      break;

#endif

#ifdef DCT_FLOAT_SUPPORTED

    case JDCT_FLOAT:

      {

	/* For float AA&N IDCT method, divisors are equal to quantization

	 * coefficients scaled by scalefactor[row]*scalefactor[col], where

	 *   scalefactor[0] = 1

	 *   scalefactor[k] = cos(k*PI/16) * sqrt(2)    for k=1..7

	 * We apply a further scale factor of 8.

	 * What's actually stored is 1/divisor so that the inner loop can

	 * use a multiplication rather than a division.

	 */

	FAST_FLOAT * fdtbl;

	int row, col;

	static const double aanscalefactor[DCTSIZE] = {

	  1.0, 1.387039845, 1.306562965, 1.175875602,

	  1.0, 0.785694958, 0.541196100, 0.275899379

	};

	if (fdct->float_divisors[qtblno] == NULL) {

	  fdct->float_divisors[qtblno] = (FAST_FLOAT *)

	    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,

					DCTSIZE2 * SIZEOF(FAST_FLOAT));

	}

	fdtbl = fdct->float_divisors[qtblno];

	i = 0;

	for (row = 0; row < DCTSIZE; row++) {

	  for (col = 0; col < DCTSIZE; col++) {

	    fdtbl[i] = (FAST_FLOAT)

	      (1.0 / (((double) qtbl->quantval[i] *

		       aanscalefactor[row] * aanscalefactor[col] * 8.0)));

	    i++;

	  }

	}

      }

      fdct->pub.forward_DCT[ci] = forward_DCT_float;

      break;

#endif

    default:

      ERREXIT(cinfo, JERR_NOT_COMPILED);

      break;

    }

  }

}

/*