modules/javafx.graphics/src/main/native-iio/libjpeg7/jddctmgr.c

@@ -1,9 +1,10 @@
 /*
  * jddctmgr.c
  *
  * Copyright (C) 1994-1996, Thomas G. Lane.
+ * Modified 2002-2013 by Guido Vollbeding.
  * This file is part of the Independent JPEG Group's software.
  * For conditions of distribution and use, see the accompanying README file.
  *
  * This file contains the inverse-DCT management logic.
  * This code selects a particular IDCT implementation to be used,

@@ -322,10 +323,11 @@
       {
         /* For float AA&N IDCT method, multipliers 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 1/8.
          */
         FLOAT_MULT_TYPE * fmtbl = (FLOAT_MULT_TYPE *) compptr->dct_table;
         int row, col;
         static const double aanscalefactor[DCTSIZE] = {
           1.0, 1.387039845, 1.306562965, 1.175875602,

@@ -335,11 +337,11 @@
         i = 0;
         for (row = 0; row < DCTSIZE; row++) {
           for (col = 0; col < DCTSIZE; col++) {
             fmtbl[i] = (FLOAT_MULT_TYPE)
               ((double) qtbl->quantval[i] *
-               aanscalefactor[row] * aanscalefactor[col]);
+               aanscalefactor[row] * aanscalefactor[col] * 0.125);
             i++;
           }
         }
       }
       break;

@@ -364,11 +366,11 @@
   jpeg_component_info *compptr;
 
   idct = (my_idct_ptr)
     (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
                                 SIZEOF(my_idct_controller));
-  cinfo->idct = (struct jpeg_inverse_dct *) idct;
+  cinfo->idct = &idct->pub;
   idct->pub.start_pass = start_pass;
 
   for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
        ci++, compptr++) {
     /* Allocate and pre-zero a multiplier table for each component */