Update to libjpeg_turbo 1.4.90

(Duplicate of https://codereview.chromium.org/1939823002/ for landing.)

TBR=noel@chromium.org,thakis@chromium.org
BUG=608347, 398235, 591927

Review URL: https://codereview.chromium.org/1953443002 .

1 files changed, 202 insertions, 214 deletions

diff --git a/jquant2.c b/jquant2.c
index 9b060e5..cfbd0f1 100644
--- a/jquant2.c
+++ b/jquant2.c
@@ -4,8 +4,9 @@
  * This file was part of the Independent JPEG Group's software:
  * Copyright (C) 1991-1996, Thomas G. Lane.
  * libjpeg-turbo Modifications:
- * Copyright (C) 2009, D. R. Commander.
- * For conditions of distribution and use, see the accompanying README file.
+ * Copyright (C) 2009, 2014-2015, D. R. Commander.
+ * For conditions of distribution and use, see the accompanying README.ijg
+ * file.
  *
  * This file contains 2-pass color quantization (color mapping) routines.
  * These routines provide selection of a custom color map for an image,
@@ -43,7 +44,7 @@
  * color space, and repeatedly splits the "largest" remaining box until we
  * have as many boxes as desired colors.  Then the mean color in each
  * remaining box becomes one of the possible output colors.
- * 
+ *
  * The second pass over the image maps each input pixel to the closest output
  * color (optionally after applying a Floyd-Steinberg dithering correction).
  * This mapping is logically trivial, but making it go fast enough requires
@@ -72,9 +73,9 @@
  * probably need to change these scale factors.
  */
 
-#define R_SCALE 2		/* scale R distances by this much */
-#define G_SCALE 3		/* scale G distances by this much */
-#define B_SCALE 1		/* and B by this much */
+#define R_SCALE 2               /* scale R distances by this much */
+#define G_SCALE 3               /* scale G distances by this much */
+#define B_SCALE 1               /* and B by this much */
 
 static const int c_scales[3]={R_SCALE, G_SCALE, B_SCALE};
 #define C0_SCALE c_scales[rgb_red[cinfo->out_color_space]]
@@ -102,9 +103,7 @@ static const int c_scales[3]={R_SCALE, G_SCALE, B_SCALE};
  * machines, we can't just allocate the histogram in one chunk.  Instead
  * of a true 3-D array, we use a row of pointers to 2-D arrays.  Each
  * pointer corresponds to a C0 value (typically 2^5 = 32 pointers) and
- * each 2-D array has 2^6*2^5 = 2048 or 2^6*2^6 = 4096 entries.  Note that
- * on 80x86 machines, the pointer row is in near memory but the actual
- * arrays are in far memory (same arrangement as we use for image arrays).
+ * each 2-D array has 2^6*2^5 = 2048 or 2^6*2^6 = 4096 entries.
  */
 
 #define MAXNUMCOLORS  (MAXJSAMPLE+1) /* maximum size of colormap */
@@ -112,9 +111,9 @@ static const int c_scales[3]={R_SCALE, G_SCALE, B_SCALE};
 /* These will do the right thing for either R,G,B or B,G,R color order,
  * but you may not like the results for other color orders.
  */
-#define HIST_C0_BITS  5		/* bits of precision in R/B histogram */
-#define HIST_C1_BITS  6		/* bits of precision in G histogram */
-#define HIST_C2_BITS  5		/* bits of precision in B/R histogram */
+#define HIST_C0_BITS  5         /* bits of precision in R/B histogram */
+#define HIST_C1_BITS  6         /* bits of precision in G histogram */
+#define HIST_C2_BITS  5         /* bits of precision in B/R histogram */
 
 /* Number of elements along histogram axes. */
 #define HIST_C0_ELEMS  (1<<HIST_C0_BITS)
@@ -127,13 +126,13 @@ static const int c_scales[3]={R_SCALE, G_SCALE, B_SCALE};
 #define C2_SHIFT  (BITS_IN_JSAMPLE-HIST_C2_BITS)
 
 
-typedef UINT16 histcell;	/* histogram cell; prefer an unsigned type */
+typedef UINT16 histcell;        /* histogram cell; prefer an unsigned type */
 
-typedef histcell FAR * histptr;	/* for pointers to histogram cells */
+typedef histcell *histptr; /* for pointers to histogram cells */
 
 typedef histcell hist1d[HIST_C2_ELEMS]; /* typedefs for the array */
-typedef hist1d FAR * hist2d;	/* type for the 2nd-level pointers */
-typedef hist2d * hist3d;	/* type for top-level pointer */
+typedef hist1d *hist2d;         /* type for the 2nd-level pointers */
+typedef hist2d *hist3d;         /* type for top-level pointer */
 
 
 /* Declarations for Floyd-Steinberg dithering.
@@ -141,8 +140,8 @@ typedef hist2d * hist3d;	/* type for top-level pointer */
  * Errors are accumulated into the array fserrors[], at a resolution of
  * 1/16th of a pixel count.  The error at a given pixel is propagated
  * to its not-yet-processed neighbors using the standard F-S fractions,
- *		...	(here)	7/16
- *		3/16	5/16	1/16
+ *              ...     (here)  7/16
+ *              3/16    5/16    1/16
  * We work left-to-right on even rows, right-to-left on odd rows.
  *
  * We can get away with a single array (holding one row's worth of errors)
@@ -155,20 +154,17 @@ typedef hist2d * hist3d;	/* type for top-level pointer */
  * The fserrors[] array has (#columns + 2) entries; the extra entry at
  * each end saves us from special-casing the first and last pixels.
  * Each entry is three values long, one value for each color component.
- *
- * Note: on a wide image, we might not have enough room in a PC's near data
- * segment to hold the error array; so it is allocated with alloc_large.
  */
 
 #if BITS_IN_JSAMPLE == 8
-typedef INT16 FSERROR;		/* 16 bits should be enough */
-typedef int LOCFSERROR;		/* use 'int' for calculation temps */
+typedef INT16 FSERROR;          /* 16 bits should be enough */
+typedef int LOCFSERROR;         /* use 'int' for calculation temps */
 #else
-typedef INT32 FSERROR;		/* may need more than 16 bits */
-typedef INT32 LOCFSERROR;	/* be sure calculation temps are big enough */
+typedef JLONG FSERROR;          /* may need more than 16 bits */
+typedef JLONG LOCFSERROR;       /* be sure calculation temps are big enough */
 #endif
 
-typedef FSERROR FAR *FSERRPTR;	/* pointer to error array (in FAR storage!) */
+typedef FSERROR *FSERRPTR;      /* pointer to error array */
 
 
 /* Private subobject */
@@ -177,21 +173,21 @@ typedef struct {
   struct jpeg_color_quantizer pub; /* public fields */
 
   /* Space for the eventually created colormap is stashed here */
-  JSAMPARRAY sv_colormap;	/* colormap allocated at init time */
-  int desired;			/* desired # of colors = size of colormap */
+  JSAMPARRAY sv_colormap;       /* colormap allocated at init time */
+  int desired;                  /* desired # of colors = size of colormap */
 
   /* Variables for accumulating image statistics */
-  hist3d histogram;		/* pointer to the histogram */
+  hist3d histogram;             /* pointer to the histogram */
 
-  boolean needs_zeroed;		/* TRUE if next pass must zero histogram */
+  boolean needs_zeroed;         /* TRUE if next pass must zero histogram */
 
   /* Variables for Floyd-Steinberg dithering */
-  FSERRPTR fserrors;		/* accumulated errors */
-  boolean on_odd_row;		/* flag to remember which row we are on */
-  int * error_limiter;		/* table for clamping the applied error */
+  FSERRPTR fserrors;            /* accumulated errors */
+  boolean on_odd_row;           /* flag to remember which row we are on */
+  int *error_limiter;           /* table for clamping the applied error */
 } my_cquantizer;
 
-typedef my_cquantizer * my_cquantize_ptr;
+typedef my_cquantizer *my_cquantize_ptr;
 
 
 /*
@@ -205,7 +201,7 @@ typedef my_cquantizer * my_cquantize_ptr;
 
 METHODDEF(void)
 prescan_quantize (j_decompress_ptr cinfo, JSAMPARRAY input_buf,
-		  JSAMPARRAY output_buf, int num_rows)
+                  JSAMPARRAY output_buf, int num_rows)
 {
   my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;
   register JSAMPROW ptr;
@@ -220,11 +216,11 @@ prescan_quantize (j_decompress_ptr cinfo, JSAMPARRAY input_buf,
     for (col = width; col > 0; col--) {
       /* get pixel value and index into the histogram */
       histp = & histogram[GETJSAMPLE(ptr[0]) >> C0_SHIFT]
-			 [GETJSAMPLE(ptr[1]) >> C1_SHIFT]
-			 [GETJSAMPLE(ptr[2]) >> C2_SHIFT];
+                         [GETJSAMPLE(ptr[1]) >> C1_SHIFT]
+                         [GETJSAMPLE(ptr[2]) >> C2_SHIFT];
       /* increment, check for overflow and undo increment if so. */
       if (++(*histp) <= 0)
-	(*histp)--;
+        (*histp)--;
       ptr += 3;
     }
   }
@@ -244,12 +240,12 @@ typedef struct {
   int c1min, c1max;
   int c2min, c2max;
   /* The volume (actually 2-norm) of the box */
-  INT32 volume;
+  JLONG volume;
   /* The number of nonzero histogram cells within this box */
   long colorcount;
 } box;
 
-typedef box * boxptr;
+typedef box *boxptr;
 
 
 LOCAL(boxptr)
@@ -261,7 +257,7 @@ find_biggest_color_pop (boxptr boxlist, int numboxes)
   register int i;
   register long maxc = 0;
   boxptr which = NULL;
-  
+
   for (i = 0, boxp = boxlist; i < numboxes; i++, boxp++) {
     if (boxp->colorcount > maxc && boxp->volume > 0) {
       which = boxp;
@@ -279,9 +275,9 @@ find_biggest_volume (boxptr boxlist, int numboxes)
 {
   register boxptr boxp;
   register int i;
-  register INT32 maxv = 0;
+  register JLONG maxv = 0;
   boxptr which = NULL;
-  
+
   for (i = 0, boxp = boxlist; i < numboxes; i++, boxp++) {
     if (boxp->volume > maxv) {
       which = boxp;
@@ -302,77 +298,77 @@ update_box (j_decompress_ptr cinfo, boxptr boxp)
   histptr histp;
   int c0,c1,c2;
   int c0min,c0max,c1min,c1max,c2min,c2max;
-  INT32 dist0,dist1,dist2;
+  JLONG dist0,dist1,dist2;
   long ccount;
-  
+
   c0min = boxp->c0min;  c0max = boxp->c0max;
   c1min = boxp->c1min;  c1max = boxp->c1max;
   c2min = boxp->c2min;  c2max = boxp->c2max;
-  
+
   if (c0max > c0min)
     for (c0 = c0min; c0 <= c0max; c0++)
       for (c1 = c1min; c1 <= c1max; c1++) {
-	histp = & histogram[c0][c1][c2min];
-	for (c2 = c2min; c2 <= c2max; c2++)
-	  if (*histp++ != 0) {
-	    boxp->c0min = c0min = c0;
-	    goto have_c0min;
-	  }
+        histp = & histogram[c0][c1][c2min];
+        for (c2 = c2min; c2 <= c2max; c2++)
+          if (*histp++ != 0) {
+            boxp->c0min = c0min = c0;
+            goto have_c0min;
+          }
       }
  have_c0min:
   if (c0max > c0min)
     for (c0 = c0max; c0 >= c0min; c0--)
       for (c1 = c1min; c1 <= c1max; c1++) {
-	histp = & histogram[c0][c1][c2min];
-	for (c2 = c2min; c2 <= c2max; c2++)
-	  if (*histp++ != 0) {
-	    boxp->c0max = c0max = c0;
-	    goto have_c0max;
-	  }
+        histp = & histogram[c0][c1][c2min];
+        for (c2 = c2min; c2 <= c2max; c2++)
+          if (*histp++ != 0) {
+            boxp->c0max = c0max = c0;
+            goto have_c0max;
+          }
       }
  have_c0max:
   if (c1max > c1min)
     for (c1 = c1min; c1 <= c1max; c1++)
       for (c0 = c0min; c0 <= c0max; c0++) {
-	histp = & histogram[c0][c1][c2min];
-	for (c2 = c2min; c2 <= c2max; c2++)
-	  if (*histp++ != 0) {
-	    boxp->c1min = c1min = c1;
-	    goto have_c1min;
-	  }
+        histp = & histogram[c0][c1][c2min];
+        for (c2 = c2min; c2 <= c2max; c2++)
+          if (*histp++ != 0) {
+            boxp->c1min = c1min = c1;
+            goto have_c1min;
+          }
       }
  have_c1min:
   if (c1max > c1min)
     for (c1 = c1max; c1 >= c1min; c1--)
       for (c0 = c0min; c0 <= c0max; c0++) {
-	histp = & histogram[c0][c1][c2min];
-	for (c2 = c2min; c2 <= c2max; c2++)
-	  if (*histp++ != 0) {
-	    boxp->c1max = c1max = c1;
-	    goto have_c1max;
-	  }
+        histp = & histogram[c0][c1][c2min];
+        for (c2 = c2min; c2 <= c2max; c2++)
+          if (*histp++ != 0) {
+            boxp->c1max = c1max = c1;
+            goto have_c1max;
+          }
       }
  have_c1max:
   if (c2max > c2min)
     for (c2 = c2min; c2 <= c2max; c2++)
       for (c0 = c0min; c0 <= c0max; c0++) {
-	histp = & histogram[c0][c1min][c2];
-	for (c1 = c1min; c1 <= c1max; c1++, histp += HIST_C2_ELEMS)
-	  if (*histp != 0) {
-	    boxp->c2min = c2min = c2;
-	    goto have_c2min;
-	  }
+        histp = & histogram[c0][c1min][c2];
+        for (c1 = c1min; c1 <= c1max; c1++, histp += HIST_C2_ELEMS)
+          if (*histp != 0) {
+            boxp->c2min = c2min = c2;
+            goto have_c2min;
+          }
       }
  have_c2min:
   if (c2max > c2min)
     for (c2 = c2max; c2 >= c2min; c2--)
       for (c0 = c0min; c0 <= c0max; c0++) {
-	histp = & histogram[c0][c1min][c2];
-	for (c1 = c1min; c1 <= c1max; c1++, histp += HIST_C2_ELEMS)
-	  if (*histp != 0) {
-	    boxp->c2max = c2max = c2;
-	    goto have_c2max;
-	  }
+        histp = & histogram[c0][c1min][c2];
+        for (c1 = c1min; c1 <= c1max; c1++, histp += HIST_C2_ELEMS)
+          if (*histp != 0) {
+            boxp->c2max = c2max = c2;
+            goto have_c2max;
+          }
       }
  have_c2max:
 
@@ -388,16 +384,16 @@ update_box (j_decompress_ptr cinfo, boxptr boxp)
   dist1 = ((c1max - c1min) << C1_SHIFT) * C1_SCALE;
   dist2 = ((c2max - c2min) << C2_SHIFT) * C2_SCALE;
   boxp->volume = dist0*dist0 + dist1*dist1 + dist2*dist2;
-  
+
   /* Now scan remaining volume of box and compute population */
   ccount = 0;
   for (c0 = c0min; c0 <= c0max; c0++)
     for (c1 = c1min; c1 <= c1max; c1++) {
       histp = & histogram[c0][c1][c2min];
       for (c2 = c2min; c2 <= c2max; c2++, histp++)
-	if (*histp != 0) {
-	  ccount++;
-	}
+        if (*histp != 0) {
+          ccount++;
+        }
     }
   boxp->colorcount = ccount;
 }
@@ -405,7 +401,7 @@ update_box (j_decompress_ptr cinfo, boxptr boxp)
 
 LOCAL(int)
 median_cut (j_decompress_ptr cinfo, boxptr boxlist, int numboxes,
-	    int desired_colors)
+            int desired_colors)
 /* Repeatedly select and split the largest box until we have enough boxes */
 {
   int n,lb;
@@ -421,9 +417,9 @@ median_cut (j_decompress_ptr cinfo, boxptr boxlist, int numboxes,
     } else {
       b1 = find_biggest_volume(boxlist, numboxes);
     }
-    if (b1 == NULL)		/* no splittable boxes left! */
+    if (b1 == NULL)             /* no splittable boxes left! */
       break;
-    b2 = &boxlist[numboxes];	/* where new box will go */
+    b2 = &boxlist[numboxes];    /* where new box will go */
     /* Copy the color bounds to the new box. */
     b2->c0max = b1->c0max; b2->c1max = b1->c1max; b2->c2max = b1->c2max;
     b2->c0min = b1->c0min; b2->c1min = b1->c1min; b2->c2min = b1->c2min;
@@ -495,24 +491,24 @@ compute_color (j_decompress_ptr cinfo, boxptr boxp, int icolor)
   long c0total = 0;
   long c1total = 0;
   long c2total = 0;
-  
+
   c0min = boxp->c0min;  c0max = boxp->c0max;
   c1min = boxp->c1min;  c1max = boxp->c1max;
   c2min = boxp->c2min;  c2max = boxp->c2max;
-  
+
   for (c0 = c0min; c0 <= c0max; c0++)
     for (c1 = c1min; c1 <= c1max; c1++) {
       histp = & histogram[c0][c1][c2min];
       for (c2 = c2min; c2 <= c2max; c2++) {
-	if ((count = *histp++) != 0) {
-	  total += count;
-	  c0total += ((c0 << C0_SHIFT) + ((1<<C0_SHIFT)>>1)) * count;
-	  c1total += ((c1 << C1_SHIFT) + ((1<<C1_SHIFT)>>1)) * count;
-	  c2total += ((c2 << C2_SHIFT) + ((1<<C2_SHIFT)>>1)) * count;
-	}
+        if ((count = *histp++) != 0) {
+          total += count;
+          c0total += ((c0 << C0_SHIFT) + ((1<<C0_SHIFT)>>1)) * count;
+          c1total += ((c1 << C1_SHIFT) + ((1<<C1_SHIFT)>>1)) * count;
+          c2total += ((c2 << C2_SHIFT) + ((1<<C2_SHIFT)>>1)) * count;
+        }
       }
     }
-  
+
   cinfo->colormap[0][icolor] = (JSAMPLE) ((c0total + (total>>1)) / total);
   cinfo->colormap[1][icolor] = (JSAMPLE) ((c1total + (total>>1)) / total);
   cinfo->colormap[2][icolor] = (JSAMPLE) ((c2total + (total>>1)) / total);
@@ -529,7 +525,7 @@ select_colors (j_decompress_ptr cinfo, int desired_colors)
 
   /* Allocate workspace for box list */
   boxlist = (boxptr) (*cinfo->mem->alloc_small)
-    ((j_common_ptr) cinfo, JPOOL_IMAGE, desired_colors * SIZEOF(box));
+    ((j_common_ptr) cinfo, JPOOL_IMAGE, desired_colors * sizeof(box));
   /* Initialize one box containing whole space */
   numboxes = 1;
   boxlist[0].c0min = 0;
@@ -576,7 +572,7 @@ select_colors (j_decompress_ptr cinfo, int desired_colors)
  * distance from every colormap entry to every histogram cell.  Unfortunately,
  * it needs a work array to hold the best-distance-so-far for each histogram
  * cell (because the inner loop has to be over cells, not colormap entries).
- * The work array elements have to be INT32s, so the work array would need
+ * The work array elements have to be JLONGs, so the work array would need
  * 256Kb at our recommended precision.  This is not feasible in DOS machines.
  *
  * To get around these problems, we apply Thomas' method to compute the
@@ -628,7 +624,7 @@ select_colors (j_decompress_ptr cinfo, int desired_colors)
 
 LOCAL(int)
 find_nearby_colors (j_decompress_ptr cinfo, int minc0, int minc1, int minc2,
-		    JSAMPLE colorlist[])
+                    JSAMPLE colorlist[])
 /* Locate the colormap entries close enough to an update box to be candidates
  * for the nearest entry to some cell(s) in the update box.  The update box
  * is specified by the center coordinates of its first cell.  The number of
@@ -642,8 +638,8 @@ find_nearby_colors (j_decompress_ptr cinfo, int minc0, int minc1, int minc2,
   int maxc0, maxc1, maxc2;
   int centerc0, centerc1, centerc2;
   int i, x, ncolors;
-  INT32 minmaxdist, min_dist, max_dist, tdist;
-  INT32 mindist[MAXNUMCOLORS];	/* min distance to colormap entry i */
+  JLONG minmaxdist, min_dist, max_dist, tdist;
+  JLONG mindist[MAXNUMCOLORS];  /* min distance to colormap entry i */
 
   /* Compute true coordinates of update box's upper corner and center.
    * Actually we compute the coordinates of the center of the upper-corner
@@ -685,11 +681,11 @@ find_nearby_colors (j_decompress_ptr cinfo, int minc0, int minc1, int minc2,
       /* within cell range so no contribution to min_dist */
       min_dist = 0;
       if (x <= centerc0) {
-	tdist = (x - maxc0) * C0_SCALE;
-	max_dist = tdist*tdist;
+        tdist = (x - maxc0) * C0_SCALE;
+        max_dist = tdist*tdist;
       } else {
-	tdist = (x - minc0) * C0_SCALE;
-	max_dist = tdist*tdist;
+        tdist = (x - minc0) * C0_SCALE;
+        max_dist = tdist*tdist;
       }
     }
 
@@ -707,11 +703,11 @@ find_nearby_colors (j_decompress_ptr cinfo, int minc0, int minc1, int minc2,
     } else {
       /* within cell range so no contribution to min_dist */
       if (x <= centerc1) {
-	tdist = (x - maxc1) * C1_SCALE;
-	max_dist += tdist*tdist;
+        tdist = (x - maxc1) * C1_SCALE;
+        max_dist += tdist*tdist;
       } else {
-	tdist = (x - minc1) * C1_SCALE;
-	max_dist += tdist*tdist;
+        tdist = (x - minc1) * C1_SCALE;
+        max_dist += tdist*tdist;
       }
     }
 
@@ -729,15 +725,15 @@ find_nearby_colors (j_decompress_ptr cinfo, int minc0, int minc1, int minc2,
     } else {
       /* within cell range so no contribution to min_dist */
       if (x <= centerc2) {
-	tdist = (x - maxc2) * C2_SCALE;
-	max_dist += tdist*tdist;
+        tdist = (x - maxc2) * C2_SCALE;
+        max_dist += tdist*tdist;
       } else {
-	tdist = (x - minc2) * C2_SCALE;
-	max_dist += tdist*tdist;
+        tdist = (x - minc2) * C2_SCALE;
+        max_dist += tdist*tdist;
       }
     }
 
-    mindist[i] = min_dist;	/* save away the results */
+    mindist[i] = min_dist;      /* save away the results */
     if (max_dist < minmaxdist)
       minmaxdist = max_dist;
   }
@@ -757,7 +753,7 @@ find_nearby_colors (j_decompress_ptr cinfo, int minc0, int minc1, int minc2,
 
 LOCAL(void)
 find_best_colors (j_decompress_ptr cinfo, int minc0, int minc1, int minc2,
-		  int numcolors, JSAMPLE colorlist[], JSAMPLE bestcolor[])
+                  int numcolors, JSAMPLE colorlist[], JSAMPLE bestcolor[])
 /* Find the closest colormap entry for each cell in the update box,
  * given the list of candidate colors prepared by find_nearby_colors.
  * Return the indexes of the closest entries in the bestcolor[] array.
@@ -767,31 +763,31 @@ find_best_colors (j_decompress_ptr cinfo, int minc0, int minc1, int minc2,
 {
   int ic0, ic1, ic2;
   int i, icolor;
-  register INT32 * bptr;	/* pointer into bestdist[] array */
-  JSAMPLE * cptr;		/* pointer into bestcolor[] array */
-  INT32 dist0, dist1;		/* initial distance values */
-  register INT32 dist2;		/* current distance in inner loop */
-  INT32 xx0, xx1;		/* distance increments */
-  register INT32 xx2;
-  INT32 inc0, inc1, inc2;	/* initial values for increments */
+  register JLONG *bptr;         /* pointer into bestdist[] array */
+  JSAMPLE *cptr;                /* pointer into bestcolor[] array */
+  JLONG dist0, dist1;           /* initial distance values */
+  register JLONG dist2;         /* current distance in inner loop */
+  JLONG xx0, xx1;               /* distance increments */
+  register JLONG xx2;
+  JLONG inc0, inc1, inc2;       /* initial values for increments */
   /* This array holds the distance to the nearest-so-far color for each cell */
-  INT32 bestdist[BOX_C0_ELEMS * BOX_C1_ELEMS * BOX_C2_ELEMS];
+  JLONG bestdist[BOX_C0_ELEMS * BOX_C1_ELEMS * BOX_C2_ELEMS];
 
   /* Initialize best-distance for each cell of the update box */
   bptr = bestdist;
   for (i = BOX_C0_ELEMS*BOX_C1_ELEMS*BOX_C2_ELEMS-1; i >= 0; i--)
     *bptr++ = 0x7FFFFFFFL;
-  
+
   /* For each color selected by find_nearby_colors,
    * compute its distance to the center of each cell in the box.
    * If that's less than best-so-far, update best distance and color number.
    */
-  
+
   /* Nominal steps between cell centers ("x" in Thomas article) */
 #define STEP_C0  ((1 << C0_SHIFT) * C0_SCALE)
 #define STEP_C1  ((1 << C1_SHIFT) * C1_SCALE)
 #define STEP_C2  ((1 << C2_SHIFT) * C2_SCALE)
-  
+
   for (i = 0; i < numcolors; i++) {
     icolor = GETJSAMPLE(colorlist[i]);
     /* Compute (square of) distance from minc0/c1/c2 to this color */
@@ -813,20 +809,20 @@ find_best_colors (j_decompress_ptr cinfo, int minc0, int minc1, int minc2,
       dist1 = dist0;
       xx1 = inc1;
       for (ic1 = BOX_C1_ELEMS-1; ic1 >= 0; ic1--) {
-	dist2 = dist1;
-	xx2 = inc2;
-	for (ic2 = BOX_C2_ELEMS-1; ic2 >= 0; ic2--) {
-	  if (dist2 < *bptr) {
-	    *bptr = dist2;
-	    *cptr = (JSAMPLE) icolor;
-	  }
-	  dist2 += xx2;
-	  xx2 += 2 * STEP_C2 * STEP_C2;
-	  bptr++;
-	  cptr++;
-	}
-	dist1 += xx1;
-	xx1 += 2 * STEP_C1 * STEP_C1;
+        dist2 = dist1;
+        xx2 = inc2;
+        for (ic2 = BOX_C2_ELEMS-1; ic2 >= 0; ic2--) {
+          if (dist2 < *bptr) {
+            *bptr = dist2;
+            *cptr = (JSAMPLE) icolor;
+          }
+          dist2 += xx2;
+          xx2 += 2 * STEP_C2 * STEP_C2;
+          bptr++;
+          cptr++;
+        }
+        dist1 += xx1;
+        xx1 += 2 * STEP_C1 * STEP_C1;
       }
       dist0 += xx0;
       xx0 += 2 * STEP_C0 * STEP_C0;
@@ -843,13 +839,13 @@ fill_inverse_cmap (j_decompress_ptr cinfo, int c0, int c1, int c2)
 {
   my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;
   hist3d histogram = cquantize->histogram;
-  int minc0, minc1, minc2;	/* lower left corner of update box */
+  int minc0, minc1, minc2;      /* lower left corner of update box */
   int ic0, ic1, ic2;
-  register JSAMPLE * cptr;	/* pointer into bestcolor[] array */
-  register histptr cachep;	/* pointer into main cache array */
+  register JSAMPLE *cptr;       /* pointer into bestcolor[] array */
+  register histptr cachep;      /* pointer into main cache array */
   /* This array lists the candidate colormap indexes. */
   JSAMPLE colorlist[MAXNUMCOLORS];
-  int numcolors;		/* number of candidate colors */
+  int numcolors;                /* number of candidate colors */
   /* This array holds the actually closest colormap index for each cell. */
   JSAMPLE bestcolor[BOX_C0_ELEMS * BOX_C1_ELEMS * BOX_C2_ELEMS];
 
@@ -865,7 +861,7 @@ fill_inverse_cmap (j_decompress_ptr cinfo, int c0, int c1, int c2)
   minc0 = (c0 << BOX_C0_SHIFT) + ((1 << C0_SHIFT) >> 1);
   minc1 = (c1 << BOX_C1_SHIFT) + ((1 << C1_SHIFT) >> 1);
   minc2 = (c2 << BOX_C2_SHIFT) + ((1 << C2_SHIFT) >> 1);
-  
+
   /* Determine which colormap entries are close enough to be candidates
    * for the nearest entry to some cell in the update box.
    */
@@ -873,10 +869,10 @@ fill_inverse_cmap (j_decompress_ptr cinfo, int c0, int c1, int c2)
 
   /* Determine the actually nearest colors. */
   find_best_colors(cinfo, minc0, minc1, minc2, numcolors, colorlist,
-		   bestcolor);
+                   bestcolor);
 
   /* Save the best color numbers (plus 1) in the main cache array */
-  c0 <<= BOX_C0_LOG;		/* convert ID back to base cell indexes */
+  c0 <<= BOX_C0_LOG;            /* convert ID back to base cell indexes */
   c1 <<= BOX_C1_LOG;
   c2 <<= BOX_C2_LOG;
   cptr = bestcolor;
@@ -884,7 +880,7 @@ fill_inverse_cmap (j_decompress_ptr cinfo, int c0, int c1, int c2)
     for (ic1 = 0; ic1 < BOX_C1_ELEMS; ic1++) {
       cachep = & histogram[c0+ic0][c1+ic1][c2];
       for (ic2 = 0; ic2 < BOX_C2_ELEMS; ic2++) {
-	*cachep++ = (histcell) (GETJSAMPLE(*cptr++) + 1);
+        *cachep++ = (histcell) (GETJSAMPLE(*cptr++) + 1);
       }
     }
   }
@@ -897,7 +893,7 @@ fill_inverse_cmap (j_decompress_ptr cinfo, int c0, int c1, int c2)
 
 METHODDEF(void)
 pass2_no_dither (j_decompress_ptr cinfo,
-		 JSAMPARRAY input_buf, JSAMPARRAY output_buf, int num_rows)
+                 JSAMPARRAY input_buf, JSAMPARRAY output_buf, int num_rows)
 /* This version performs no dithering */
 {
   my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;
@@ -921,7 +917,7 @@ pass2_no_dither (j_decompress_ptr cinfo,
       /* If we have not seen this color before, find nearest colormap entry */
       /* and update the cache */
       if (*cachep == 0)
-	fill_inverse_cmap(cinfo, c0,c1,c2);
+        fill_inverse_cmap(cinfo, c0,c1,c2);
       /* Now emit the colormap index for this cell */
       *outptr++ = (JSAMPLE) (*cachep - 1);
     }
@@ -931,20 +927,20 @@ pass2_no_dither (j_decompress_ptr cinfo,
 
 METHODDEF(void)
 pass2_fs_dither (j_decompress_ptr cinfo,
-		 JSAMPARRAY input_buf, JSAMPARRAY output_buf, int num_rows)
+                 JSAMPARRAY input_buf, JSAMPARRAY output_buf, int num_rows)
 /* This version performs Floyd-Steinberg dithering */
 {
   my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;
   hist3d histogram = cquantize->histogram;
-  register LOCFSERROR cur0, cur1, cur2;	/* current error or pixel value */
+  register LOCFSERROR cur0, cur1, cur2; /* current error or pixel value */
   LOCFSERROR belowerr0, belowerr1, belowerr2; /* error for pixel below cur */
   LOCFSERROR bpreverr0, bpreverr1, bpreverr2; /* error for below/prev col */
-  register FSERRPTR errorptr;	/* => fserrors[] at column before current */
-  JSAMPROW inptr;		/* => current input pixel */
-  JSAMPROW outptr;		/* => current output pixel */
+  register FSERRPTR errorptr;   /* => fserrors[] at column before current */
+  JSAMPROW inptr;               /* => current input pixel */
+  JSAMPROW outptr;              /* => current output pixel */
   histptr cachep;
-  int dir;			/* +1 or -1 depending on direction */
-  int dir3;			/* 3*dir, for advancing inptr & errorptr */
+  int dir;                      /* +1 or -1 depending on direction */
+  int dir3;                     /* 3*dir, for advancing inptr & errorptr */
   int row;
   JDIMENSION col;
   JDIMENSION width = cinfo->output_width;
@@ -960,7 +956,7 @@ pass2_fs_dither (j_decompress_ptr cinfo,
     outptr = output_buf[row];
     if (cquantize->on_odd_row) {
       /* work right to left in this row */
-      inptr += (width-1) * 3;	/* so point to rightmost pixel */
+      inptr += (width-1) * 3;   /* so point to rightmost pixel */
       outptr += width-1;
       dir = -1;
       dir3 = -3;
@@ -1012,53 +1008,44 @@ pass2_fs_dither (j_decompress_ptr cinfo,
       /* If we have not seen this color before, find nearest colormap */
       /* entry and update the cache */
       if (*cachep == 0)
-	fill_inverse_cmap(cinfo, cur0>>C0_SHIFT,cur1>>C1_SHIFT,cur2>>C2_SHIFT);
+        fill_inverse_cmap(cinfo, cur0>>C0_SHIFT,cur1>>C1_SHIFT,cur2>>C2_SHIFT);
       /* Now emit the colormap index for this cell */
       { register int pixcode = *cachep - 1;
-	*outptr = (JSAMPLE) pixcode;
-	/* Compute representation error for this pixel */
-	cur0 -= GETJSAMPLE(colormap0[pixcode]);
-	cur1 -= GETJSAMPLE(colormap1[pixcode]);
-	cur2 -= GETJSAMPLE(colormap2[pixcode]);
+        *outptr = (JSAMPLE) pixcode;
+        /* Compute representation error for this pixel */
+        cur0 -= GETJSAMPLE(colormap0[pixcode]);
+        cur1 -= GETJSAMPLE(colormap1[pixcode]);
+        cur2 -= GETJSAMPLE(colormap2[pixcode]);
       }
       /* Compute error fractions to be propagated to adjacent pixels.
        * Add these into the running sums, and simultaneously shift the
        * next-line error sums left by 1 column.
        */
-      { register LOCFSERROR bnexterr, delta;
-
-	bnexterr = cur0;	/* Process component 0 */
-	delta = cur0 * 2;
-	cur0 += delta;		/* form error * 3 */
-	errorptr[0] = (FSERROR) (bpreverr0 + cur0);
-	cur0 += delta;		/* form error * 5 */
-	bpreverr0 = belowerr0 + cur0;
-	belowerr0 = bnexterr;
-	cur0 += delta;		/* form error * 7 */
-	bnexterr = cur1;	/* Process component 1 */
-	delta = cur1 * 2;
-	cur1 += delta;		/* form error * 3 */
-	errorptr[1] = (FSERROR) (bpreverr1 + cur1);
-	cur1 += delta;		/* form error * 5 */
-	bpreverr1 = belowerr1 + cur1;
-	belowerr1 = bnexterr;
-	cur1 += delta;		/* form error * 7 */
-	bnexterr = cur2;	/* Process component 2 */
-	delta = cur2 * 2;
-	cur2 += delta;		/* form error * 3 */
-	errorptr[2] = (FSERROR) (bpreverr2 + cur2);
-	cur2 += delta;		/* form error * 5 */
-	bpreverr2 = belowerr2 + cur2;
-	belowerr2 = bnexterr;
-	cur2 += delta;		/* form error * 7 */
+      { register LOCFSERROR bnexterr;
+
+        bnexterr = cur0;        /* Process component 0 */
+        errorptr[0] = (FSERROR) (bpreverr0 + cur0 * 3);
+        bpreverr0 = belowerr0 + cur0 * 5;
+        belowerr0 = bnexterr;
+        cur0 *= 7;
+        bnexterr = cur1;        /* Process component 1 */
+        errorptr[1] = (FSERROR) (bpreverr1 + cur1 * 3);
+        bpreverr1 = belowerr1 + cur1 * 5;
+        belowerr1 = bnexterr;
+        cur1 *= 7;
+        bnexterr = cur2;        /* Process component 2 */
+        errorptr[2] = (FSERROR) (bpreverr2 + cur2 * 3);
+        bpreverr2 = belowerr2 + cur2 * 5;
+        belowerr2 = bnexterr;
+        cur2 *= 7;
       }
       /* At this point curN contains the 7/16 error value to be propagated
        * to the next pixel on the current line, and all the errors for the
        * next line have been shifted over.  We are therefore ready to move on.
        */
-      inptr += dir3;		/* Advance pixel pointers to next column */
+      inptr += dir3;            /* Advance pixel pointers to next column */
       outptr += dir;
-      errorptr += dir3;		/* advance errorptr to current column */
+      errorptr += dir3;         /* advance errorptr to current column */
     }
     /* Post-loop cleanup: we must unload the final error values into the
      * final fserrors[] entry.  Note we need not unload belowerrN because
@@ -1093,12 +1080,12 @@ init_error_limit (j_decompress_ptr cinfo)
 /* Allocate and fill in the error_limiter table */
 {
   my_cquantize_ptr cquantize = (my_cquantize_ptr) cinfo->cquantize;
-  int * table;
+  int *table;
   int in, out;
 
   table = (int *) (*cinfo->mem->alloc_small)
-    ((j_common_ptr) cinfo, JPOOL_IMAGE, (MAXJSAMPLE*2+1) * SIZEOF(int));
-  table += MAXJSAMPLE;		/* so can index -MAXJSAMPLE .. +MAXJSAMPLE */
+    ((j_common_ptr) cinfo, JPOOL_IMAGE, (MAXJSAMPLE*2+1) * sizeof(int));
+  table += MAXJSAMPLE;          /* so can index -MAXJSAMPLE .. +MAXJSAMPLE */
   cquantize->error_limiter = table;
 
 #define STEPSIZE ((MAXJSAMPLE+1)/16)
@@ -1181,16 +1168,16 @@ start_pass_2_quant (j_decompress_ptr cinfo, boolean is_pre_scan)
 
     if (cinfo->dither_mode == JDITHER_FS) {
       size_t arraysize = (size_t) ((cinfo->output_width + 2) *
-				   (3 * SIZEOF(FSERROR)));
+                                   (3 * sizeof(FSERROR)));
       /* Allocate Floyd-Steinberg workspace if we didn't already. */
       if (cquantize->fserrors == NULL)
-	cquantize->fserrors = (FSERRPTR) (*cinfo->mem->alloc_large)
-	  ((j_common_ptr) cinfo, JPOOL_IMAGE, arraysize);
+        cquantize->fserrors = (FSERRPTR) (*cinfo->mem->alloc_large)
+          ((j_common_ptr) cinfo, JPOOL_IMAGE, arraysize);
       /* Initialize the propagated errors to zero. */
-      jzero_far((void FAR *) cquantize->fserrors, arraysize);
+      jzero_far((void *) cquantize->fserrors, arraysize);
       /* Make the error-limit table if we didn't already. */
       if (cquantize->error_limiter == NULL)
-	init_error_limit(cinfo);
+        init_error_limit(cinfo);
       cquantize->on_odd_row = FALSE;
     }
 
@@ -1198,8 +1185,8 @@ start_pass_2_quant (j_decompress_ptr cinfo, boolean is_pre_scan)
   /* Zero the histogram or inverse color map, if necessary */
   if (cquantize->needs_zeroed) {
     for (i = 0; i < HIST_C0_ELEMS; i++) {
-      jzero_far((void FAR *) histogram[i],
-		HIST_C1_ELEMS*HIST_C2_ELEMS * SIZEOF(histcell));
+      jzero_far((void *) histogram[i],
+                HIST_C1_ELEMS*HIST_C2_ELEMS * sizeof(histcell));
     }
     cquantize->needs_zeroed = FALSE;
   }
@@ -1232,11 +1219,11 @@ jinit_2pass_quantizer (j_decompress_ptr cinfo)
 
   cquantize = (my_cquantize_ptr)
     (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
-				SIZEOF(my_cquantizer));
+                                sizeof(my_cquantizer));
   cinfo->cquantize = (struct jpeg_color_quantizer *) cquantize;
   cquantize->pub.start_pass = start_pass_2_quant;
   cquantize->pub.new_color_map = new_color_map_2_quant;
-  cquantize->fserrors = NULL;	/* flag optional arrays not allocated */
+  cquantize->fserrors = NULL;   /* flag optional arrays not allocated */
   cquantize->error_limiter = NULL;
 
   /* Make sure jdmaster didn't give me a case I can't handle */
@@ -1245,17 +1232,17 @@ jinit_2pass_quantizer (j_decompress_ptr cinfo)
 
   /* Allocate the histogram/inverse colormap storage */
   cquantize->histogram = (hist3d) (*cinfo->mem->alloc_small)
-    ((j_common_ptr) cinfo, JPOOL_IMAGE, HIST_C0_ELEMS * SIZEOF(hist2d));
+    ((j_common_ptr) cinfo, JPOOL_IMAGE, HIST_C0_ELEMS * sizeof(hist2d));
   for (i = 0; i < HIST_C0_ELEMS; i++) {
     cquantize->histogram[i] = (hist2d) (*cinfo->mem->alloc_large)
       ((j_common_ptr) cinfo, JPOOL_IMAGE,
-       HIST_C1_ELEMS*HIST_C2_ELEMS * SIZEOF(histcell));
+       HIST_C1_ELEMS*HIST_C2_ELEMS * sizeof(histcell));
   }
   cquantize->needs_zeroed = TRUE; /* histogram is garbage now */
 
   /* Allocate storage for the completed colormap, if required.
-   * We do this now since it is FAR storage and may affect
-   * the memory manager's space calculations.
+   * We do this now since it may affect the memory manager's space
+   * calculations.
    */
   if (cinfo->enable_2pass_quant) {
     /* Make sure color count is acceptable */
@@ -1278,14 +1265,15 @@ jinit_2pass_quantizer (j_decompress_ptr cinfo)
     cinfo->dither_mode = JDITHER_FS;
 
   /* Allocate Floyd-Steinberg workspace if necessary.
-   * This isn't really needed until pass 2, but again it is FAR storage.
-   * Although we will cope with a later change in dither_mode,
-   * we do not promise to honor max_memory_to_use if dither_mode changes.
+   * This isn't really needed until pass 2, but again it may affect the memory
+   * manager's space calculations.  Although we will cope with a later change
+   * in dither_mode, we do not promise to honor max_memory_to_use if
+   * dither_mode changes.
    */
   if (cinfo->dither_mode == JDITHER_FS) {
     cquantize->fserrors = (FSERRPTR) (*cinfo->mem->alloc_large)
       ((j_common_ptr) cinfo, JPOOL_IMAGE,
-       (size_t) ((cinfo->output_width + 2) * (3 * SIZEOF(FSERROR))));
+       (size_t) ((cinfo->output_width + 2) * (3 * sizeof(FSERROR))));
     /* Might as well create the error-limiting table too. */
     init_error_limit(cinfo);
   }