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diff --git a/packages/pasjpeg/src/jdct.pas b/packages/pasjpeg/src/jdct.pas
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+Unit Jdct;
+
+{ Orignal: jdct.h; Copyright (C) 1994-1996, Thomas G. Lane. }
+
+{ This include file contains common declarations for the forward and
+  inverse DCT modules.  These declarations are private to the DCT managers
+  (jcdctmgr.c, jddctmgr.c) and the individual DCT algorithms.
+  The individual DCT algorithms are kept in separate files to ease
+  machine-dependent tuning (e.g., assembly coding). }
+
+interface
+
+{$I jconfig.inc}
+
+uses
+  jmorecfg;
+
+
+{ A forward DCT routine is given a pointer to a work area of type DCTELEM[];
+  the DCT is to be performed in-place in that buffer.  Type DCTELEM is int
+  for 8-bit samples, INT32 for 12-bit samples.  (NOTE: Floating-point DCT
+  implementations use an array of type FAST_FLOAT, instead.)
+  The DCT inputs are expected to be signed (range +-CENTERJSAMPLE).
+  The DCT outputs are returned scaled up by a factor of 8; they therefore
+  have a range of +-8K for 8-bit data, +-128K for 12-bit data.  This
+  convention improves accuracy in integer implementations and saves some
+  work in floating-point ones.
+  Quantization of the output coefficients is done by jcdctmgr.c. }
+
+
+{$ifdef BITS_IN_JSAMPLE_IS_8}
+type
+  DCTELEM = int;                { 16 or 32 bits is fine }
+{$else}
+type                            { must have 32 bits }
+  DCTELEM = INT32;
+{$endif}
+type
+  jTDctElem = 0..(MaxInt div SizeOf(DCTELEM))-1;
+  DCTELEM_FIELD = array[jTDctElem] of DCTELEM;
+  DCTELEM_FIELD_PTR = ^DCTELEM_FIELD;
+  DCTELEMPTR = ^DCTELEM;
+
+type
+  forward_DCT_method_ptr = procedure(var data : array of DCTELEM);
+  float_DCT_method_ptr = procedure(var data : array of FAST_FLOAT);
+
+
+{ An inverse DCT routine is given a pointer to the input JBLOCK and a pointer
+  to an output sample array.  The routine must dequantize the input data as
+  well as perform the IDCT; for dequantization, it uses the multiplier table
+  pointed to by compptr->dct_table.  The output data is to be placed into the
+  sample array starting at a specified column.  (Any row offset needed will
+  be applied to the array pointer before it is passed to the IDCT code.)
+  Note that the number of samples emitted by the IDCT routine is
+  DCT_scaled_size * DCT_scaled_size. }
+
+
+{ typedef inverse_DCT_method_ptr is declared in jpegint.h }
+
+
+{ Each IDCT routine has its own ideas about the best dct_table element type. }
+
+
+type
+  ISLOW_MULT_TYPE = MULTIPLIER;  { short or int, whichever is faster }
+
+{$ifdef BITS_IN_JSAMPLE_IS_8}
+type
+  IFAST_MULT_TYPE = MULTIPLIER;  { 16 bits is OK, use short if faster }
+const
+  IFAST_SCALE_BITS = 2;         { fractional bits in scale factors }
+{$else}
+type
+  IFAST_MULT_TYPE = INT32;      {  need 32 bits for scaled quantizers }
+const
+  IFAST_SCALE_BITS = 13;        { fractional bits in scale factors }
+{$endif}
+type
+  FLOAT_MULT_TYPE = FAST_FLOAT; { preferred floating type }
+
+const
+  RANGE_MASK = (MAXJSAMPLE * 4 + 3); { 2 bits wider than legal samples }
+
+type
+  jTMultType = 0..(MaxInt div SizeOf(ISLOW_MULT_TYPE))-1;
+  ISLOW_MULT_TYPE_FIELD = array[jTMultType] of ISLOW_MULT_TYPE;
+  ISLOW_MULT_TYPE_FIELD_PTR = ^ISLOW_MULT_TYPE_FIELD;
+  ISLOW_MULT_TYPE_PTR = ^ISLOW_MULT_TYPE;
+
+  jTFloatType = 0..(MaxInt div SizeOf(FLOAT_MULT_TYPE))-1;
+  FLOAT_MULT_TYPE_FIELD = array[jTFloatType] of FLOAT_MULT_TYPE;
+  FLOAT_MULT_TYPE_FIELD_PTR = ^FLOAT_MULT_TYPE_FIELD;
+  FLOAT_MULT_TYPE_PTR = ^FLOAT_MULT_TYPE;
+
+  jTFastType = 0..(MaxInt div SizeOf(IFAST_MULT_TYPE))-1;
+  IFAST_MULT_TYPE_FIELD = array[jTFastType] of IFAST_MULT_TYPE;
+  IFAST_MULT_TYPE_FIELD_PTR = ^IFAST_MULT_TYPE_FIELD;
+  IFAST_MULT_TYPE_PTR = ^IFAST_MULT_TYPE;
+
+type
+  jTFastFloat = 0..(MaxInt div SizeOf(FAST_FLOAT))-1;
+  FAST_FLOAT_FIELD = array[jTFastFloat] of FAST_FLOAT;
+  FAST_FLOAT_FIELD_PTR = ^FAST_FLOAT_FIELD;
+  FAST_FLOAT_PTR = ^FAST_FLOAT;
+
+implementation
+
+end.