Program: CWE-190
Project: CVE-2017-6889
Buggy source:
/*
   dcraw.c -- Dave Coffin's raw photo decoder
   Copyright 1997-2013 by Dave Coffin, dcoffin a cybercom o net

   This is a command-line ANSI C program to convert raw photos from
   any digital camera on any computer running any operating system.

   No license is required to download and use dcraw.c.  However,
   to lawfully redistribute dcraw, you must either (a) offer, at
   no extra charge, full source code* for all executable files
   containing RESTRICTED functions, (b) distribute this code under
   the GPL Version 2 or later, (c) remove all RESTRICTED functions,
   re-implement them, or copy them from an earlier, unrestricted
   Revision of dcraw.c, or (d) purchase a license from the author.

   The functions that process Foveon images have been RESTRICTED
   since Revision 1.237.  All other code remains free for all uses.

   *If you have not modified dcraw.c in any way, a link to my
   homepage qualifies as "full source code".

   $Revision: 1.456 $
   $Date: 2013/06/16 18:01:08 $
 */

#define getbits(n) getbithuff(n,0)

char * CLASS foveon_gets (int offset, char *str, int len)
{
  int i;
  fseek (ifp, offset, SEEK_SET);
  for (i=0; i < len-1; i++)
    if ((str[i] = get2()) == 0) break;
  str[i] = 0;
  return str;
}

void CLASS parse_foveon()
{
  int entries, img=0, off, len, tag, save, i, wide, high, pent, poff[256][2];
  char name[64], value[64];

  order = 0x4949;			/* Little-endian */
  fseek (ifp, 36, SEEK_SET);
  flip = get4();
  fseek (ifp, -4, SEEK_END);
  fseek (ifp, get4(), SEEK_SET);
  if (get4() != 0x64434553) return;	/* SECd */
  entries = (get4(),get4());
  while (entries--) {
    off = get4();
    len = get4();
    tag = get4();
    save = ftell(ifp);
    fseek (ifp, off, SEEK_SET);
    if (get4() != (0x20434553 | (tag << 24))) return;
    switch (tag) {
      case 0x47414d49:			/* IMAG */
      case 0x32414d49:			/* IMA2 */
	fseek (ifp, 8, SEEK_CUR);
	pent = get4();
	wide = get4();
	high = get4();
	if (wide > raw_width && high > raw_height) {
	  switch (pent) {
	    case  5:  load_flags = 1;
	    case  6:  load_raw = &CLASS foveon_sd_load_raw;  break;
	    case 30:  load_raw = &CLASS foveon_dp_load_raw;  break;
	    default:  load_raw = 0;
	  }
	  raw_width  = wide;
	  raw_height = high;
	  data_offset = off+28;
	  is_foveon = 1;
	}
	fseek (ifp, off+28, SEEK_SET);
	if (fgetc(ifp) == 0xff && fgetc(ifp) == 0xd8
		&& thumb_length < len-28) {
	  thumb_offset = off+28;
	  thumb_length = len-28;
	  write_thumb = &CLASS jpeg_thumb;
	}
	if (++img == 2 && !thumb_length) {
	  thumb_offset = off+24;
	  thumb_width = wide;
	  thumb_height = high;
	  write_thumb = &CLASS foveon_thumb;
	}
	break;
      case 0x464d4143:			/* CAMF */
	meta_offset = off+8;
	meta_length = len-28;
	break;
      case 0x504f5250:			/* PROP */
	pent = (get4(),get4());
	fseek (ifp, 12, SEEK_CUR);
	off += pent*8 + 24;
	if ((unsigned) pent > 256) pent=256;
	for (i=0; i < pent*2; i++)
	  poff[0][i] = off + get4()*2;
	for (i=0; i < pent; i++) {
	  foveon_gets (poff[i][0], name, 64);
	  foveon_gets (poff[i][1], value, 64);
	  if (!strcmp (name, "ISO"))
	    iso_speed = atoi(value);
	  if (!strcmp (name, "CAMMANUF"))
	    strcpy (make, value);
	  if (!strcmp (name, "CAMMODEL"))
	    strcpy (model, value);
	  if (!strcmp (name, "WB_DESC"))
	    strcpy (model2, value);
	  if (!strcmp (name, "TIME"))
	    timestamp = atoi(value);
	  if (!strcmp (name, "EXPTIME"))
	    shutter = atoi(value) / 1000000.0;
	  if (!strcmp (name, "APERTURE"))
	    aperture = atof(value);
	  if (!strcmp (name, "FLENGTH"))
	    focal_len = atof(value);
	}
#ifdef LOCALTIME
	timestamp = mktime (gmtime (&timestamp));
#endif
    }
    fseek (ifp, save, SEEK_SET);
  }
}


/* RESTRICTED code starts here */

void CLASS foveon_decoder (unsigned size, unsigned code)
{
  static unsigned huff[1024];
  struct decode *cur;
  int i, len;

  if (!code) {
    for (i=0; i < size; i++)
      huff[i] = get4();
    memset (first_decode, 0, sizeof first_decode);
    free_decode = first_decode;
  }
  cur = free_decode++;
  if (free_decode > first_decode+2048) {
#ifdef LIBRAW_LIBRARY_BUILD
      throw LIBRAW_EXCEPTION_DECODE_RAW;
#else
    fprintf (stderr,_("%s: decoder table overflow\n"), ifname);
    longjmp (failure, 2);
#endif
  }
  if (code)
    for (i=0; i < size; i++)
      if (huff[i] == code) {
	cur->leaf = i;
	return;
      }
  if ((len = code >> 27) > 26) return;
  code = (len+1) << 27 | (code & 0x3ffffff) << 1;

  cur->branch[0] = free_decode;
  foveon_decoder (size, code);
  cur->branch[1] = free_decode;
  foveon_decoder (size, code+1);
}

#ifdef LIBRAW_LIBRARY_BUILD
#define T imgdata.thumbnail
#define ID libraw_internal_data.internal_data

void LibRaw::foveon_thumb_loader (void)
{
    unsigned bwide, row, col, bitbuf=0, bit=1, c, i;
    struct decode *dindex;
    short pred[3];
    
    if(T.thumb) free(T.thumb);
    T.thumb = NULL;
    
    bwide = get4();
    if (bwide > 0) 
        {
            if (bwide < (unsigned)T.twidth*3) return;
            T.thumb = (char*)malloc(3*T.twidth * T.theight);
            merror (T.thumb, "foveon_thumb()");
            char *buf = (char*)malloc(bwide); 
            merror (buf, "foveon_thumb()");
            for (row=0; row < T.theight; row++) 
                {
                    ID.input->read(buf, 1, bwide);
                    memmove(T.thumb+(row*T.twidth*3),buf,T.twidth*3);
                }
            free(buf);
            T.tlength = 3*T.twidth * T.theight;
            T.tformat = LIBRAW_THUMBNAIL_BITMAP;
            return;
        }
    else 
        {
            foveon_decoder (256, 0);
            T.thumb = (char*)malloc(3*T.twidth * T.theight);
            char *bufp = T.thumb;
            merror (T.thumb, "foveon_thumb()");
            for (row=0; row < T.theight; row++) 
                {
                    memset (pred, 0, sizeof pred);
                    if (!bit) get4();
                    for (bit=col=0; col < T.twidth; col++)
                        for(c=0;c<3;c++) 
                            {
                                for (dindex=first_decode; dindex->branch[0]; ) 
                                    {
                                        if ((bit = (bit-1) & 31) == 31)
                                            for (i=0; i < 4; i++)
                                                bitbuf = (bitbuf << 8) + ID.input->get_char();
                                        dindex = dindex->branch[bitbuf >> bit & 1];
                                    }
                                pred[c] += dindex->leaf;
                                (*bufp++)=pred[c];
                            }
                }
            T.tformat = LIBRAW_THUMBNAIL_BITMAP;
            T.tlength = 3*T.twidth * T.theight;
        }
    return;
}
#endif

void CLASS foveon_thumb()
{
  unsigned bwide, row, col, bitbuf=0, bit=1, c, i;
  char *buf;
  struct decode *dindex;
  short pred[3];

  bwide = get4();
  fprintf (ofp, "P6\n%d %d\n255\n", thumb_width, thumb_height);
  if (bwide > 0) {
    if (bwide < thumb_width*3) return;
    buf = (char *) malloc (bwide);
    merror (buf, "foveon_thumb()");
    for (row=0; row < thumb_height; row++) {
      fread  (buf, 1, bwide, ifp);
      fwrite (buf, 3, thumb_width, ofp);
    }
    free (buf);
    return;
  }
  foveon_decoder (256, 0);

  for (row=0; row < thumb_height; row++) {
    memset (pred, 0, sizeof pred);
    if (!bit) get4();
    for (bit=col=0; col < thumb_width; col++)
      FORC3 {
	for (dindex=first_decode; dindex->branch[0]; ) {
	  if ((bit = (bit-1) & 31) == 31)
	    for (i=0; i < 4; i++)
	      bitbuf = (bitbuf << 8) + fgetc(ifp);
	  dindex = dindex->branch[bitbuf >> bit & 1];
	}
	pred[c] += dindex->leaf;
	fputc (pred[c], ofp);
      }
  }
}

void CLASS foveon_sd_load_raw()
{
  struct decode *dindex;
  short diff[1024];
  unsigned bitbuf=0;
  int pred[3], row, col, bit=-1, c, i;

  read_shorts ((ushort *) diff, 1024);
  if (!load_flags) foveon_decoder (1024, 0);

  for (row=0; row < height; row++) {
#ifdef LIBRAW_LIBRARY_BUILD
    checkCancel();
#endif
    memset (pred, 0, sizeof pred);
    if (!bit && !load_flags && atoi(model+2) < 14) get4();
    for (col=bit=0; col < width; col++) {
      if (load_flags) {
	bitbuf = get4();
	FORC3 pred[2-c] += diff[bitbuf >> c*10 & 0x3ff];
      }
      else FORC3 {
	for (dindex=first_decode; dindex->branch[0]; ) {
	  if ((bit = (bit-1) & 31) == 31)
	    for (i=0; i < 4; i++)
	      bitbuf = (bitbuf << 8) + fgetc(ifp);
	  dindex = dindex->branch[bitbuf >> bit & 1];
	}
	pred[c] += diff[dindex->leaf];
	if (pred[c] >> 16 && ~pred[c] >> 16) derror();
      }
      FORC3 image[row*width+col][c] = pred[c];
    }
  }
}

void CLASS foveon_huff (ushort *huff)
{
  int i, j, clen, code;

  huff[0] = 8;
  for (i=0; i < 13; i++) {
    clen = getc(ifp);
    code = getc(ifp);
    for (j=0; j < 256 >> clen; )
      huff[code+ ++j] = clen << 8 | i;
  }
  get2();
}

void CLASS foveon_dp_load_raw()
{
  unsigned c, roff[4], row, col, diff;
  ushort huff[512], vpred[2][2], hpred[2];

  fseek (ifp, 8, SEEK_CUR);
  foveon_huff (huff);
  roff[0] = 48;
  FORC3 roff[c+1] = -(-(roff[c] + get4()) & -16);
  FORC3 {
    fseek (ifp, data_offset+roff[c], SEEK_SET);
    getbits(-1);
    vpred[0][0] = vpred[0][1] = vpred[1][0] = vpred[1][1] = 512;
    for (row=0; row < height; row++) {
#ifdef LIBRAW_LIBRARY_BUILD
    checkCancel();
#endif
      for (col=0; col < width; col++) {
	diff = ljpeg_diff(huff);
	if (col < 2) hpred[col] = vpred[row & 1][col] += diff;
	else hpred[col & 1] += diff;
	image[row*width+col][c] = hpred[col & 1];
      }
    }
  }
}

void CLASS foveon_load_camf()
{
  unsigned type, wide, high, i, j, row, col, diff;
  ushort huff[258], vpred[2][2] = {{512,512},{512,512}}, hpred[2];

  fseek (ifp, meta_offset, SEEK_SET);
  type = get4();  get4();  get4();
  wide = get4();
  high = get4();
  if (type == 2) {
    fread (meta_data, 1, meta_length, ifp);
    for (i=0; i < meta_length; i++) {
      high = (high * 1597 + 51749) % 244944;
      wide = high * (INT64) 301593171 >> 24;
      meta_data[i] ^= ((((high << 8) - wide) >> 1) + wide) >> 17;
    }
  } else if (type == 4) {
    free (meta_data);
    meta_data = (char *) malloc (meta_length = wide*high*3/2);
    merror (meta_data, "foveon_load_camf()");
    foveon_huff (huff);
    get4();
    getbits(-1);
    for (j=row=0; row < high; row++) {
      for (col=0; col < wide; col++) {
	diff = ljpeg_diff(huff);
	if (col < 2) hpred[col] = vpred[row & 1][col] += diff;
	else         hpred[col & 1] += diff;
	if (col & 1) {
	  meta_data[j++] = hpred[0] >> 4;
	  meta_data[j++] = hpred[0] << 4 | hpred[1] >> 8;
	  meta_data[j++] = hpred[1];
        }
      }
    }
  } else
    fprintf (stderr,_("%s has unknown CAMF type %d.\n"), ifname, type);
}

const char * CLASS foveon_camf_param (const char *block, const char *param)
{
  unsigned idx, num;
  char *pos, *cp, *dp;

  for (idx=0; idx < meta_length; idx += sget4(pos+8)) {
    pos = meta_data + idx;
    if (strncmp (pos, "CMb", 3)) break;
    if (pos[3] != 'P') continue;
    if (strcmp (block, pos+sget4(pos+12))) continue;
    cp = pos + sget4(pos+16);
    num = sget4(cp);
    dp = pos + sget4(cp+4);
    while (num--) {
      cp += 8;
      if (!strcmp (param, dp+sget4(cp)))
	return dp+sget4(cp+4);
    }
  }
  return 0;
}

void * CLASS foveon_camf_matrix (unsigned dim[3], const char *name)
{
  unsigned i, idx, type, ndim, size, *mat;
  char *pos, *cp, *dp;
  double dsize;

  for (idx=0; idx < meta_length; idx += sget4(pos+8)) {
    pos = meta_data + idx;
    if (strncmp (pos, "CMb", 3)) break;
    if (pos[3] != 'M') continue;
    if (strcmp (name, pos+sget4(pos+12))) continue;
    dim[0] = dim[1] = dim[2] = 1;
    cp = pos + sget4(pos+16);
    type = sget4(cp);
    if ((ndim = sget4(cp+4)) > 3) break;
    dp = pos + sget4(cp+8);
    for (i=ndim; i--; ) {
      cp += 12;
      dim[i] = sget4(cp);
    }
    if ((dsize = (double) dim[0]*dim[1]*dim[2]) > meta_length/4) break;
    mat = (unsigned *) malloc ((size = dsize) * 4);
    merror (mat, "foveon_camf_matrix()");
    for (i=0; i < size; i++)
      if (type && type != 6)
	mat[i] = sget4(dp + i*4);
      else
	mat[i] = sget4(dp + i*2) & 0xffff;
    return mat;
  }
  fprintf (stderr,_("%s: \"%s\" matrix not found!\n"), ifname, name);
  return 0;
}

int CLASS foveon_fixed (void *ptr, int size, const char *name)
{
  void *dp;
  unsigned dim[3];

  if (!name) return 0;
  dp = foveon_camf_matrix (dim, name);
  if (!dp) return 0;
  memcpy (ptr, dp, size*4);
  free (dp);
  return 1;
}

float CLASS foveon_avg (short *pix, int range[2], float cfilt)
{
  int i;
  float val, min=FLT_MAX, max=-FLT_MAX, sum=0;

  for (i=range[0]; i <= range[1]; i++) {
    sum += val = pix[i*4] + (pix[i*4]-pix[(i-1)*4]) * cfilt;
    if (min > val) min = val;
    if (max < val) max = val;
  }
  if (range[1] - range[0] == 1) return sum/2;
  return (sum - min - max) / (range[1] - range[0] - 1);
}

short * CLASS foveon_make_curve (double max, double mul, double filt)
{
  short *t_curve;
  unsigned i, size;
  double x;

  if (!filt) filt = 0.8;
  size = 4*M_PI*max / filt;
  if (size == UINT_MAX) size--;
  t_curve = (short *) calloc (size+1, sizeof *t_curve);
  merror (t_curve, "foveon_make_curve()");
  t_curve[0] = size;
  for (i=0; i < size; i++) {
    x = i*filt/max/4;
    t_curve[i+1] = (cos(x)+1)/2 * tanh(i*filt/mul) * mul + 0.5;
  }
  return t_curve;
}

void CLASS foveon_make_curves
	(short **curvep, float dq[3], float div[3], float filt)
{
  double mul[3], max=0;
  int c;

  FORC3 mul[c] = dq[c]/div[c];
  FORC3 if (max < mul[c]) max = mul[c];
  FORC3 curvep[c] = foveon_make_curve (max, mul[c], filt);
}

int CLASS foveon_apply_curve (short *t_curve, int i)
{
  if (abs(i) >= t_curve[0]) return 0;
  return i < 0 ? -t_curve[1-i] : t_curve[1+i];
}

#ifdef LIBRAW_LIBRARY_BUILD
#ifdef image
#undef image
#endif
#define image ((short(*)[4]) imgdata.image)
#else
#define image ((short (*)[4]) image)
#endif

void CLASS foveon_interpolate()
{
  static const short hood[] = { -1,-1, -1,0, -1,1, 0,-1, 0,1, 1,-1, 1,0, 1,1 };
  short *pix, prev[3], *t_curve[8], (*t_shrink)[3];
  float cfilt=0, ddft[3][3][2], ppm[3][3][3];
  float cam_xyz[3][3], correct[3][3], last[3][3], trans[3][3];
  float chroma_dq[3], color_dq[3], diag[3][3], div[3];
  float (*t_black)[3], (*sgain)[3], (*sgrow)[3];
  float fsum[3], val, frow, num;
  int row, col, c, i, j, diff, sgx, irow, sum, min, max, limit;
  int dscr[2][2], dstb[4], (*smrow[7])[3], total[4], ipix[3];
  int work[3][3], smlast, smred, smred_p=0, dev[3];
  int satlev[3], keep[4], active[4];
  unsigned dim[3], *badpix;
  double dsum=0, trsum[3];
  char str[128];
  const char* cp;

  if (verbose)
    fprintf (stderr,_("Foveon interpolation...\n"));

  foveon_load_camf();
  foveon_fixed (dscr, 4, "DarkShieldColRange");
  foveon_fixed (ppm[0][0], 27, "PostPolyMatrix");
  foveon_fixed (satlev, 3, "SaturationLevel");
  foveon_fixed (keep, 4, "KeepImageArea");
  foveon_fixed (active, 4, "ActiveImageArea");
  foveon_fixed (chroma_dq, 3, "ChromaDQ");
  foveon_fixed (color_dq, 3,
	foveon_camf_param ("IncludeBlocks", "ColorDQ") ?
		"ColorDQ" : "ColorDQCamRGB");
  if (foveon_camf_param ("IncludeBlocks", "ColumnFilter"))
  		 foveon_fixed (&cfilt, 1, "ColumnFilter");

  memset (ddft, 0, sizeof ddft);
  if (!foveon_camf_param ("IncludeBlocks", "DarkDrift")
	 || !foveon_fixed (ddft[1][0], 12, "DarkDrift"))
    for (i=0; i < 2; i++) {
      foveon_fixed (dstb, 4, i ? "DarkShieldBottom":"DarkShieldTop");
      for (row = dstb[1]; row <= dstb[3]; row++)
	for (col = dstb[0]; col <= dstb[2]; col++)
	  FORC3 ddft[i+1][c][1] += (short) image[row*width+col][c];
      FORC3 ddft[i+1][c][1] /= (dstb[3]-dstb[1]+1) * (dstb[2]-dstb[0]+1);
    }

  if (!(cp = foveon_camf_param ("WhiteBalanceIlluminants", model2)))
  { fprintf (stderr,_("%s: Invalid white balance \"%s\"\n"), ifname, model2);
    return; }
  foveon_fixed (cam_xyz, 9, cp);
  foveon_fixed (correct, 9,
	foveon_camf_param ("WhiteBalanceCorrections", model2));
  memset (last, 0, sizeof last);
  for (i=0; i < 3; i++)
    for (j=0; j < 3; j++)
      FORC3 last[i][j] += correct[i][c] * cam_xyz[c][j];

  #define LAST(x,y) last[(i+x)%3][(c+y)%3]
  for (i=0; i < 3; i++)
    FORC3 diag[c][i] = LAST(1,1)*LAST(2,2) - LAST(1,2)*LAST(2,1);
  #undef LAST
  FORC3 div[c] = diag[c][0]*0.3127 + diag[c][1]*0.329 + diag[c][2]*0.3583;
  sprintf (str, "%sRGBNeutral", model2);
  if (foveon_camf_param ("IncludeBlocks", str))
    foveon_fixed (div, 3, str);
  num = 0;
  FORC3 if (num < div[c]) num = div[c];
  FORC3 div[c] /= num;

  memset (trans, 0, sizeof trans);
  for (i=0; i < 3; i++)
    for (j=0; j < 3; j++)
      FORC3 trans[i][j] += rgb_cam[i][c] * last[c][j] * div[j];
  FORC3 trsum[c] = trans[c][0] + trans[c][1] + trans[c][2];
  dsum = (6*trsum[0] + 11*trsum[1] + 3*trsum[2]) / 20;
  for (i=0; i < 3; i++)
    FORC3 last[i][c] = trans[i][c] * dsum / trsum[i];
  memset (trans, 0, sizeof trans);
  for (i=0; i < 3; i++)
    for (j=0; j < 3; j++)
      FORC3 trans[i][j] += (i==c ? 32 : -1) * last[c][j] / 30;

  foveon_make_curves (t_curve, color_dq, div, cfilt);
  FORC3 chroma_dq[c] /= 3;
  foveon_make_curves (t_curve+3, chroma_dq, div, cfilt);
  FORC3 dsum += chroma_dq[c] / div[c];
  t_curve[6] = foveon_make_curve (dsum, dsum, cfilt);
  t_curve[7] = foveon_make_curve (dsum*2, dsum*2, cfilt);

  sgain = (float (*)[3]) foveon_camf_matrix (dim, "SpatialGain");
  if (!sgain) return;
  sgrow = (float (*)[3]) calloc (dim[1], sizeof *sgrow);
  sgx = (width + dim[1]-2) / (dim[1]-1);

  t_black = (float (*)[3]) calloc (height, sizeof *t_black);
  for (row=0; row < height; row++) {
    for (i=0; i < 6; i++)
      ddft[0][0][i] = ddft[1][0][i] +
	row / (height-1.0) * (ddft[2][0][i] - ddft[1][0][i]);
    FORC3 t_black[row][c] =
 	( foveon_avg (image[row*width]+c, dscr[0], cfilt) +
	  foveon_avg (image[row*width]+c, dscr[1], cfilt) * 3
	  - ddft[0][c][0] ) / 4 - ddft[0][c][1];
  }
  memcpy (t_black, t_black+8, sizeof *t_black*8);
  memcpy (t_black+height-11, t_black+height-22, 11*sizeof *t_black);
  memcpy (last, t_black, sizeof last);

  for (row=1; row < height-1; row++) {
    FORC3 if (last[1][c] > last[0][c]) {
	if (last[1][c] > last[2][c])
	  t_black[row][c] = (last[0][c] > last[2][c]) ? last[0][c]:last[2][c];
      } else
	if (last[1][c] < last[2][c])
	  t_black[row][c] = (last[0][c] < last[2][c]) ? last[0][c]:last[2][c];
    memmove (last, last+1, 2*sizeof last[0]);
    memcpy (last[2], t_black[row+1], sizeof last[2]);
  }
  FORC3 t_black[row][c] = (last[0][c] + last[1][c])/2;
  FORC3 t_black[0][c] = (t_black[1][c] + t_black[3][c])/2;

  val = 1 - exp(-1/24.0);
  memcpy (fsum, t_black, sizeof fsum);
  for (row=1; row < height; row++)
    FORC3 fsum[c] += t_black[row][c] =
	(t_black[row][c] - t_black[row-1][c])*val + t_black[row-1][c];
  memcpy (last[0], t_black[height-1], sizeof last[0]);
  FORC3 fsum[c] /= height;
  for (row = height; row--; )
    FORC3 last[0][c] = t_black[row][c] =
	(t_black[row][c] - fsum[c] - last[0][c])*val + last[0][c];

  memset (total, 0, sizeof total);
  for (row=2; row < height; row+=4)
    for (col=2; col < width; col+=4) {
      FORC3 total[c] += (short) image[row*width+col][c];
      total[3]++;
    }
  for (row=0; row < height; row++)
    FORC3 t_black[row][c] += fsum[c]/2 + total[c]/(total[3]*100.0);

  for (row=0; row < height; row++) {
    for (i=0; i < 6; i++)
      ddft[0][0][i] = ddft[1][0][i] +
	row / (height-1.0) * (ddft[2][0][i] - ddft[1][0][i]);
    pix = image[row*width];
    memcpy (prev, pix, sizeof prev);
    frow = row / (height-1.0) * (dim[2]-1);
    if ((irow = frow) == dim[2]-1) irow--;
    frow -= irow;
    for (i=0; i < dim[1]; i++)
      FORC3 sgrow[i][c] = sgain[ irow   *dim[1]+i][c] * (1-frow) +
			  sgain[(irow+1)*dim[1]+i][c] *    frow;
    for (col=0; col < width; col++) {
      FORC3 {
	diff = pix[c] - prev[c];
	prev[c] = pix[c];
	ipix[c] = pix[c] + floor ((diff + (diff*diff >> 14)) * cfilt
		- ddft[0][c][1] - ddft[0][c][0] * ((float) col/width - 0.5)
		- t_black[row][c] );
      }
      FORC3 {
	work[0][c] = ipix[c] * ipix[c] >> 14;
	work[2][c] = ipix[c] * work[0][c] >> 14;
	work[1][2-c] = ipix[(c+1) % 3] * ipix[(c+2) % 3] >> 14;
      }
      FORC3 {
	for (val=i=0; i < 3; i++)
	  for (  j=0; j < 3; j++)
	    val += ppm[c][i][j] * work[i][j];
	ipix[c] = floor ((ipix[c] + floor(val)) *
		( sgrow[col/sgx  ][c] * (sgx - col%sgx) +
		  sgrow[col/sgx+1][c] * (col%sgx) ) / sgx / div[c]);
	if (ipix[c] > 32000) ipix[c] = 32000;
	pix[c] = ipix[c];
      }
      pix += 4;
    }
  }
  free (t_black);
  free (sgrow);
  free (sgain);

  if ((badpix = (unsigned int *) foveon_camf_matrix (dim, "BadPixels"))) {
    for (i=0; i < dim[0]; i++) {
      col = (badpix[i] >> 8 & 0xfff) - keep[0];
      row = (badpix[i] >> 20       ) - keep[1];
      if ((unsigned)(row-1) > height-3 || (unsigned)(col-1) > width-3)
	continue;
      memset (fsum, 0, sizeof fsum);
      for (sum=j=0; j < 8; j++)
	if (badpix[i] & (1 << j)) {
	  FORC3 fsum[c] += (short)
		image[(row+hood[j*2])*width+col+hood[j*2+1]][c];
	  sum++;
	}
      if (sum) FORC3 image[row*width+col][c] = fsum[c]/sum;
    }
    free (badpix);
  }

  /* Array for 5x5 Gaussian averaging of red values */
  smrow[6] = (int (*)[3]) calloc (width*5, sizeof **smrow);
  merror (smrow[6], "foveon_interpolate()");
  for (i=0; i < 5; i++)
    smrow[i] = smrow[6] + i*width;

  /* Sharpen the reds against these Gaussian averages */
  for (smlast=-1, row=2; row < height-2; row++) {
    while (smlast < row+2) {
      for (i=0; i < 6; i++)
	smrow[(i+5) % 6] = smrow[i];
      pix = image[++smlast*width+2];
      for (col=2; col < width-2; col++) {
	smrow[4][col][0] =
	  (pix[0]*6 + (pix[-4]+pix[4])*4 + pix[-8]+pix[8] + 8) >> 4;
	pix += 4;
      }
    }
    pix = image[row*width+2];
    for (col=2; col < width-2; col++) {
      smred = ( 6 *  smrow[2][col][0]
	      + 4 * (smrow[1][col][0] + smrow[3][col][0])
	      +      smrow[0][col][0] + smrow[4][col][0] + 8 ) >> 4;
      if (col == 2)
	smred_p = smred;
      i = pix[0] + ((pix[0] - ((smred*7 + smred_p) >> 3)) >> 3);
      if (i > 32000) i = 32000;
      pix[0] = i;
      smred_p = smred;
      pix += 4;
    }
  }

  /* Adjust the brighter pixels for better linearity */
  min = 0xffff;
  FORC3 {
    i = satlev[c] / div[c];
    if (min > i) min = i;
  }
  limit = min * 9 >> 4;
  for (pix=image[0]; pix < image[height*width]; pix+=4) {
    if (pix[0] <= limit || pix[1] <= limit || pix[2] <= limit)
      continue;
    min = max = pix[0];
    for (c=1; c < 3; c++) {
      if (min > pix[c]) min = pix[c];
      if (max < pix[c]) max = pix[c];
    }
    if (min >= limit*2) {
      pix[0] = pix[1] = pix[2] = max;
    } else {
      i = 0x4000 - ((min - limit) << 14) / limit;
      i = 0x4000 - (i*i >> 14);
      i = i*i >> 14;
      FORC3 pix[c] += (max - pix[c]) * i >> 14;
    }
  }
/*
   Because photons that miss one detector often hit another,
   the sum R+G+B is much less noisy than the individual colors.
   So smooth the hues without smoothing the total.
 */
  for (smlast=-1, row=2; row < height-2; row++) {
    while (smlast < row+2) {
      for (i=0; i < 6; i++)
	smrow[(i+5) % 6] = smrow[i];
      pix = image[++smlast*width+2];
      for (col=2; col < width-2; col++) {
	FORC3 smrow[4][col][c] = (pix[c-4]+2*pix[c]+pix[c+4]+2) >> 2;
	pix += 4;
      }
    }
    pix = image[row*width+2];
    for (col=2; col < width-2; col++) {
      FORC3 dev[c] = -foveon_apply_curve (t_curve[7], pix[c] -
	((smrow[1][col][c] + 2*smrow[2][col][c] + smrow[3][col][c]) >> 2));
      sum = (dev[0] + dev[1] + dev[2]) >> 3;
      FORC3 pix[c] += dev[c] - sum;
      pix += 4;
    }
  }
  for (smlast=-1, row=2; row < height-2; row++) {
    while (smlast < row+2) {
      for (i=0; i < 6; i++)
	smrow[(i+5) % 6] = smrow[i];
      pix = image[++smlast*width+2];
      for (col=2; col < width-2; col++) {
	FORC3 smrow[4][col][c] =
		(pix[c-8]+pix[c-4]+pix[c]+pix[c+4]+pix[c+8]+2) >> 2;
	pix += 4;
      }
    }
    pix = image[row*width+2];
    for (col=2; col < width-2; col++) {
      for (total[3]=375, sum=60, c=0; c < 3; c++) {
	for (total[c]=i=0; i < 5; i++)
	  total[c] += smrow[i][col][c];
	total[3] += total[c];
	sum += pix[c];
      }
      if (sum < 0) sum = 0;
      j = total[3] > 375 ? (sum << 16) / total[3] : sum * 174;
      FORC3 pix[c] += foveon_apply_curve (t_curve[6],
		((j*total[c] + 0x8000) >> 16) - pix[c]);
      pix += 4;
    }
  }

  /* Transform the image to a different colorspace */
  for (pix=image[0]; pix < image[height*width]; pix+=4) {
    FORC3 pix[c] -= foveon_apply_curve (t_curve[c], pix[c]);
    sum = (pix[0]+pix[1]+pix[1]+pix[2]) >> 2;
    FORC3 pix[c] -= foveon_apply_curve (t_curve[c], pix[c]-sum);
    FORC3 {
      for (dsum=i=0; i < 3; i++)
	dsum += trans[c][i] * pix[i];
      if (dsum < 0)  dsum = 0;
      if (dsum > 24000) dsum = 24000;
      ipix[c] = dsum + 0.5;
    }
    FORC3 pix[c] = ipix[c];
  }

  /* Smooth the image bottom-to-top and save at 1/4 scale */
  t_shrink = (short (*)[3]) calloc ((width/4) * (height/4), sizeof *t_shrink);
  merror (t_shrink, "foveon_interpolate()");
  for (row = height/4; row--; )
    for (col=0; col < width/4; col++) {
      ipix[0] = ipix[1] = ipix[2] = 0;
      for (i=0; i < 4; i++)
	for (j=0; j < 4; j++)
	  FORC3 ipix[c] += image[(row*4+i)*width+col*4+j][c];
      FORC3
	if (row+2 > height/4)
	  t_shrink[row*(width/4)+col][c] = ipix[c] >> 4;
	else
	  t_shrink[row*(width/4)+col][c] =
	    (t_shrink[(row+1)*(width/4)+col][c]*1840 + ipix[c]*141 + 2048) >> 12;
    }
  /* From the 1/4-scale image, smooth right-to-left */
  for (row=0; row < (height & ~3); row++) {
    ipix[0] = ipix[1] = ipix[2] = 0;
    if ((row & 3) == 0)
      for (col = width & ~3 ; col--; )
	FORC3 smrow[0][col][c] = ipix[c] =
	  (t_shrink[(row/4)*(width/4)+col/4][c]*1485 + ipix[c]*6707 + 4096) >> 13;

  /* Then smooth left-to-right */
    ipix[0] = ipix[1] = ipix[2] = 0;
    for (col=0; col < (width & ~3); col++)
      FORC3 smrow[1][col][c] = ipix[c] =
	(smrow[0][col][c]*1485 + ipix[c]*6707 + 4096) >> 13;

  /* Smooth top-to-bottom */
    if (row == 0)
      memcpy (smrow[2], smrow[1], sizeof **smrow * width);
    else
      for (col=0; col < (width & ~3); col++)
	FORC3 smrow[2][col][c] =
	  (smrow[2][col][c]*6707 + smrow[1][col][c]*1485 + 4096) >> 13;

  /* Adjust the chroma toward the smooth values */
    for (col=0; col < (width & ~3); col++) {
      for (i=j=30, c=0; c < 3; c++) {
	i += smrow[2][col][c];
	j += image[row*width+col][c];
      }
      j = (j << 16) / i;
      for (sum=c=0; c < 3; c++) {
	ipix[c] = foveon_apply_curve (t_curve[c+3],
	  ((smrow[2][col][c] * j + 0x8000) >> 16) - image[row*width+col][c]);
	sum += ipix[c];
      }
      sum >>= 3;
      FORC3 {
	i = image[row*width+col][c] + ipix[c] - sum;
	if (i < 0) i = 0;
	image[row*width+col][c] = i;
      }
    }
  }
  free (t_shrink);
  free (smrow[6]);
  for (i=0; i < 8; i++)
    free (t_curve[i]);

  /* Trim off the black border */
  if (~cropbox[2] && ~cropbox[3])
    {
      // Image already cropped, do nothing
      int crop[4],c;
      for(int c=0;c<4;c++) 
        {
          crop[c] = cropbox[c];
          if(crop[c]<0)
            crop[c]=0;
        }
      if(crop[0]>=width-1) crop[0] = width - 2;
      if(crop[1]>=height-1) crop[1] = height-2;
      if(crop[0]+crop[2] >= width) crop[2] = width-crop[0];
      if(crop[1]+crop[3] >= height) crop[3] = height-crop[1];
      active[0] = crop[0];
      active[1] = crop[1];
      active[2] = crop[0]+crop[2];
      active[3] = crop[1]+crop[3];
    }
  else
    {
      active[1] -= keep[1];
      active[3] -= 2;
    }
  i = active[2] - active[0];
  for (row=0; row < active[3]-active[1]; row++)
    memcpy (image[row*i], image[(row+active[1])*width+active[0]],
            i * sizeof *image);
  width = i;
  height = row;

}
#undef image
#ifdef LIBRAW_LIBRARY_BUILD
#define image           (imgdata.image)
#endif

/* RESTRICTED code ends here */



Fixed version (ground truth):
/*
   dcraw.c -- Dave Coffin's raw photo decoder
   Copyright 1997-2013 by Dave Coffin, dcoffin a cybercom o net

   This is a command-line ANSI C program to convert raw photos from
   any digital camera on any computer running any operating system.

   No license is required to download and use dcraw.c.  However,
   to lawfully redistribute dcraw, you must either (a) offer, at
   no extra charge, full source code* for all executable files
   containing RESTRICTED functions, (b) distribute this code under
   the GPL Version 2 or later, (c) remove all RESTRICTED functions,
   re-implement them, or copy them from an earlier, unrestricted
   Revision of dcraw.c, or (d) purchase a license from the author.

   The functions that process Foveon images have been RESTRICTED
   since Revision 1.237.  All other code remains free for all uses.

   *If you have not modified dcraw.c in any way, a link to my
   homepage qualifies as "full source code".

   $Revision: 1.456 $
   $Date: 2013/06/16 18:01:08 $
 */

#define getbits(n) getbithuff(n,0)

char * CLASS foveon_gets (int offset, char *str, int len)
{
  int i;
  fseek (ifp, offset, SEEK_SET);
  for (i=0; i < len-1; i++)
    if ((str[i] = get2()) == 0) break;
  str[i] = 0;
  return str;
}

void CLASS parse_foveon()
{
  int entries, img=0, off, len, tag, save, i, wide, high, pent, poff[256][2];
  char name[64], value[64];

  order = 0x4949;			/* Little-endian */
  fseek (ifp, 36, SEEK_SET);
  flip = get4();
  fseek (ifp, -4, SEEK_END);
  fseek (ifp, get4(), SEEK_SET);
  if (get4() != 0x64434553) return;	/* SECd */
  entries = (get4(),get4());
  while (entries--) {
    off = get4();
    len = get4();
    tag = get4();
    save = ftell(ifp);
    fseek (ifp, off, SEEK_SET);
    if (get4() != (0x20434553 | (tag << 24))) return;
    switch (tag) {
      case 0x47414d49:			/* IMAG */
      case 0x32414d49:			/* IMA2 */
	fseek (ifp, 8, SEEK_CUR);
	pent = get4();
	wide = get4();
	high = get4();
	if (wide > raw_width && high > raw_height) {
	  switch (pent) {
	    case  5:  load_flags = 1;
	    case  6:  load_raw = &CLASS foveon_sd_load_raw;  break;
	    case 30:  load_raw = &CLASS foveon_dp_load_raw;  break;
	    default:  load_raw = 0;
	  }
	  raw_width  = wide;
	  raw_height = high;
	  data_offset = off+28;
	  is_foveon = 1;
	}
	fseek (ifp, off+28, SEEK_SET);
	if (fgetc(ifp) == 0xff && fgetc(ifp) == 0xd8
		&& thumb_length < len-28) {
	  thumb_offset = off+28;
	  thumb_length = len-28;
	  write_thumb = &CLASS jpeg_thumb;
	}
	if (++img == 2 && !thumb_length) {
	  thumb_offset = off+24;
	  thumb_width = wide;
	  thumb_height = high;
	  write_thumb = &CLASS foveon_thumb;
	}
	break;
      case 0x464d4143:			/* CAMF */
	meta_offset = off+8;
	meta_length = len-28;
	break;
      case 0x504f5250:			/* PROP */
	pent = (get4(),get4());
	fseek (ifp, 12, SEEK_CUR);
	off += pent*8 + 24;
	if ((unsigned) pent > 256) pent=256;
	for (i=0; i < pent*2; i++)
	  poff[0][i] = off + get4()*2;
	for (i=0; i < pent; i++) {
	  foveon_gets (poff[i][0], name, 64);
	  foveon_gets (poff[i][1], value, 64);
	  if (!strcmp (name, "ISO"))
	    iso_speed = atoi(value);
	  if (!strcmp (name, "CAMMANUF"))
	    strcpy (make, value);
	  if (!strcmp (name, "CAMMODEL"))
	    strcpy (model, value);
	  if (!strcmp (name, "WB_DESC"))
	    strcpy (model2, value);
	  if (!strcmp (name, "TIME"))
	    timestamp = atoi(value);
	  if (!strcmp (name, "EXPTIME"))
	    shutter = atoi(value) / 1000000.0;
	  if (!strcmp (name, "APERTURE"))
	    aperture = atof(value);
	  if (!strcmp (name, "FLENGTH"))
	    focal_len = atof(value);
	}
#ifdef LOCALTIME
	timestamp = mktime (gmtime (&timestamp));
#endif
    }
    fseek (ifp, save, SEEK_SET);
  }
}


/* RESTRICTED code starts here */

void CLASS foveon_decoder (unsigned size, unsigned code)
{
  static unsigned huff[1024];
  struct decode *cur;
  int i, len;

  if (!code) {
    for (i=0; i < size; i++)
      huff[i] = get4();
    memset (first_decode, 0, sizeof first_decode);
    free_decode = first_decode;
  }
  cur = free_decode++;
  if (free_decode > first_decode+2048) {
#ifdef LIBRAW_LIBRARY_BUILD
      throw LIBRAW_EXCEPTION_DECODE_RAW;
#else
    fprintf (stderr,_("%s: decoder table overflow\n"), ifname);
    longjmp (failure, 2);
#endif
  }
  if (code)
    for (i=0; i < size; i++)
      if (huff[i] == code) {
	cur->leaf = i;
	return;
      }
  if ((len = code >> 27) > 26) return;
  code = (len+1) << 27 | (code & 0x3ffffff) << 1;

  cur->branch[0] = free_decode;
  foveon_decoder (size, code);
  cur->branch[1] = free_decode;
  foveon_decoder (size, code+1);
}

#ifdef LIBRAW_LIBRARY_BUILD
#define T imgdata.thumbnail
#define ID libraw_internal_data.internal_data

void LibRaw::foveon_thumb_loader (void)
{
    unsigned bwide, row, col, bitbuf=0, bit=1, c, i;
    struct decode *dindex;
    short pred[3];
    
    if(T.thumb) free(T.thumb);
    T.thumb = NULL;
    
    bwide = get4();
    if (bwide > 0) 
        {
            if (bwide < (unsigned)T.twidth*3) return;
            T.thumb = (char*)malloc(3*T.twidth * T.theight);
            merror (T.thumb, "foveon_thumb()");
            char *buf = (char*)malloc(bwide); 
            merror (buf, "foveon_thumb()");
            for (row=0; row < T.theight; row++) 
                {
                    ID.input->read(buf, 1, bwide);
                    memmove(T.thumb+(row*T.twidth*3),buf,T.twidth*3);
                }
            free(buf);
            T.tlength = 3*T.twidth * T.theight;
            T.tformat = LIBRAW_THUMBNAIL_BITMAP;
            return;
        }
    else 
        {
            foveon_decoder (256, 0);
            T.thumb = (char*)malloc(3*T.twidth * T.theight);
            char *bufp = T.thumb;
            merror (T.thumb, "foveon_thumb()");
            for (row=0; row < T.theight; row++) 
                {
                    memset (pred, 0, sizeof pred);
                    if (!bit) get4();
                    for (bit=col=0; col < T.twidth; col++)
                        for(c=0;c<3;c++) 
                            {
                                for (dindex=first_decode; dindex->branch[0]; ) 
                                    {
                                        if ((bit = (bit-1) & 31) == 31)
                                            for (i=0; i < 4; i++)
                                                bitbuf = (bitbuf << 8) + ID.input->get_char();
                                        dindex = dindex->branch[bitbuf >> bit & 1];
                                    }
                                pred[c] += dindex->leaf;
                                (*bufp++)=pred[c];
                            }
                }
            T.tformat = LIBRAW_THUMBNAIL_BITMAP;
            T.tlength = 3*T.twidth * T.theight;
        }
    return;
}
#endif

void CLASS foveon_thumb()
{
  unsigned bwide, row, col, bitbuf=0, bit=1, c, i;
  char *buf;
  struct decode *dindex;
  short pred[3];

  bwide = get4();
  fprintf (ofp, "P6\n%d %d\n255\n", thumb_width, thumb_height);
  if (bwide > 0) {
    if (bwide < thumb_width*3) return;
    buf = (char *) malloc (bwide);
    merror (buf, "foveon_thumb()");
    for (row=0; row < thumb_height; row++) {
      fread  (buf, 1, bwide, ifp);
      fwrite (buf, 3, thumb_width, ofp);
    }
    free (buf);
    return;
  }
  foveon_decoder (256, 0);

  for (row=0; row < thumb_height; row++) {
    memset (pred, 0, sizeof pred);
    if (!bit) get4();
    for (bit=col=0; col < thumb_width; col++)
      FORC3 {
	for (dindex=first_decode; dindex->branch[0]; ) {
	  if ((bit = (bit-1) & 31) == 31)
	    for (i=0; i < 4; i++)
	      bitbuf = (bitbuf << 8) + fgetc(ifp);
	  dindex = dindex->branch[bitbuf >> bit & 1];
	}
	pred[c] += dindex->leaf;
	fputc (pred[c], ofp);
      }
  }
}

void CLASS foveon_sd_load_raw()
{
  struct decode *dindex;
  short diff[1024];
  unsigned bitbuf=0;
  int pred[3], row, col, bit=-1, c, i;

  read_shorts ((ushort *) diff, 1024);
  if (!load_flags) foveon_decoder (1024, 0);

  for (row=0; row < height; row++) {
#ifdef LIBRAW_LIBRARY_BUILD
    checkCancel();
#endif
    memset (pred, 0, sizeof pred);
    if (!bit && !load_flags && atoi(model+2) < 14) get4();
    for (col=bit=0; col < width; col++) {
      if (load_flags) {
	bitbuf = get4();
	FORC3 pred[2-c] += diff[bitbuf >> c*10 & 0x3ff];
      }
      else FORC3 {
	for (dindex=first_decode; dindex->branch[0]; ) {
	  if ((bit = (bit-1) & 31) == 31)
	    for (i=0; i < 4; i++)
	      bitbuf = (bitbuf << 8) + fgetc(ifp);
	  dindex = dindex->branch[bitbuf >> bit & 1];
	}
	pred[c] += diff[dindex->leaf];
	if (pred[c] >> 16 && ~pred[c] >> 16) derror();
      }
      FORC3 image[row*width+col][c] = pred[c];
    }
  }
}

void CLASS foveon_huff (ushort *huff)
{
  int i, j, clen, code;

  huff[0] = 8;
  for (i=0; i < 13; i++) {
    clen = getc(ifp);
    code = getc(ifp);
    for (j=0; j < 256 >> clen; )
      huff[code+ ++j] = clen << 8 | i;
  }
  get2();
}

void CLASS foveon_dp_load_raw()
{
  unsigned c, roff[4], row, col, diff;
  ushort huff[1024], vpred[2][2], hpred[2];

  fseek (ifp, 8, SEEK_CUR);
  foveon_huff (huff);
  roff[0] = 48;
  FORC3 roff[c+1] = -(-(roff[c] + get4()) & -16);
  FORC3 {
    fseek (ifp, data_offset+roff[c], SEEK_SET);
    getbits(-1);
    vpred[0][0] = vpred[0][1] = vpred[1][0] = vpred[1][1] = 512;
    for (row=0; row < height; row++) {
#ifdef LIBRAW_LIBRARY_BUILD
    checkCancel();
#endif
      for (col=0; col < width; col++) {
	diff = ljpeg_diff(huff);
	if (col < 2) hpred[col] = vpred[row & 1][col] += diff;
	else hpred[col & 1] += diff;
	image[row*width+col][c] = hpred[col & 1];
      }
    }
  }
}

void CLASS foveon_load_camf()
{
  unsigned type, wide, high, i, j, row, col, diff;
  ushort huff[1024], vpred[2][2] = {{512,512},{512,512}}, hpred[2];

  fseek (ifp, meta_offset, SEEK_SET);
  type = get4();  get4();  get4();
  wide = get4();
  high = get4();
#ifdef LIBRAW_LIBRARY_BUILD
  if(wide>32767 || high > 32767 || wide*high > 20000000)
     throw LIBRAW_EXCEPTION_IO_CORRUPT;
#endif
  if (type == 2) {
    fread (meta_data, 1, meta_length, ifp);
    for (i=0; i < meta_length; i++) {
      high = (high * 1597 + 51749) % 244944;
      wide = high * (INT64) 301593171 >> 24;
      meta_data[i] ^= ((((high << 8) - wide) >> 1) + wide) >> 17;
    }
  } else if (type == 4) {
    free (meta_data);
    meta_data = (char *) malloc (meta_length = wide*high*3/2);
    merror (meta_data, "foveon_load_camf()");
    foveon_huff (huff);
    get4();
    getbits(-1);
    for (j=row=0; row < high; row++) {
      for (col=0; col < wide; col++) {
	diff = ljpeg_diff(huff);
	if (col < 2) hpred[col] = vpred[row & 1][col] += diff;
	else         hpred[col & 1] += diff;
	if (col & 1) {
	  meta_data[j++] = hpred[0] >> 4;
	  meta_data[j++] = hpred[0] << 4 | hpred[1] >> 8;
	  meta_data[j++] = hpred[1];
        }
      }
    }
  } else
    fprintf (stderr,_("%s has unknown CAMF type %d.\n"), ifname, type);
}

const char * CLASS foveon_camf_param (const char *block, const char *param)
{
  unsigned idx, num;
  char *pos, *cp, *dp;

  for (idx=0; idx < meta_length; idx += sget4(pos+8)) {
    pos = meta_data + idx;
    if (strncmp (pos, "CMb", 3)) break;
    if (pos[3] != 'P') continue;
    if (strcmp (block, pos+sget4(pos+12))) continue;
    cp = pos + sget4(pos+16);
    num = sget4(cp);
    dp = pos + sget4(cp+4);
    while (num--) {
      cp += 8;
      if (!strcmp (param, dp+sget4(cp)))
	return dp+sget4(cp+4);
    }
  }
  return 0;
}

void * CLASS foveon_camf_matrix (unsigned dim[3], const char *name)
{
  unsigned i, idx, type, ndim, size, *mat;
  char *pos, *cp, *dp;
  double dsize;

  for (idx=0; idx < meta_length; idx += sget4(pos+8)) {
    pos = meta_data + idx;
    if (strncmp (pos, "CMb", 3)) break;
    if (pos[3] != 'M') continue;
    if (strcmp (name, pos+sget4(pos+12))) continue;
    dim[0] = dim[1] = dim[2] = 1;
    cp = pos + sget4(pos+16);
    type = sget4(cp);
    if ((ndim = sget4(cp+4)) > 3) break;
    dp = pos + sget4(cp+8);
    for (i=ndim; i--; ) {
      cp += 12;
      dim[i] = sget4(cp);
    }
    if ((dsize = (double) dim[0]*dim[1]*dim[2]) > meta_length/4) break;
    mat = (unsigned *) malloc ((size = dsize) * 4);
    merror (mat, "foveon_camf_matrix()");
    for (i=0; i < size; i++)
      if (type && type != 6)
	mat[i] = sget4(dp + i*4);
      else
	mat[i] = sget4(dp + i*2) & 0xffff;
    return mat;
  }
  fprintf (stderr,_("%s: \"%s\" matrix not found!\n"), ifname, name);
  return 0;
}

int CLASS foveon_fixed (void *ptr, int size, const char *name)
{
  void *dp;
  unsigned dim[3];

  if (!name) return 0;
  dp = foveon_camf_matrix (dim, name);
  if (!dp) return 0;
  memcpy (ptr, dp, size*4);
  free (dp);
  return 1;
}

float CLASS foveon_avg (short *pix, int range[2], float cfilt)
{
  int i;
  float val, min=FLT_MAX, max=-FLT_MAX, sum=0;

  for (i=range[0]; i <= range[1]; i++) {
    sum += val = pix[i*4] + (pix[i*4]-pix[(i-1)*4]) * cfilt;
    if (min > val) min = val;
    if (max < val) max = val;
  }
  if (range[1] - range[0] == 1) return sum/2;
  return (sum - min - max) / (range[1] - range[0] - 1);
}

short * CLASS foveon_make_curve (double max, double mul, double filt)
{
  short *t_curve;
  unsigned i, size;
  double x;

  if (!filt) filt = 0.8;
  size = 4*M_PI*max / filt;
  if (size == UINT_MAX) size--;
  t_curve = (short *) calloc (size+1, sizeof *t_curve);
  merror (t_curve, "foveon_make_curve()");
  t_curve[0] = size;
  for (i=0; i < size; i++) {
    x = i*filt/max/4;
    t_curve[i+1] = (cos(x)+1)/2 * tanh(i*filt/mul) * mul + 0.5;
  }
  return t_curve;
}

void CLASS foveon_make_curves
	(short **curvep, float dq[3], float div[3], float filt)
{
  double mul[3], max=0;
  int c;

  FORC3 mul[c] = dq[c]/div[c];
  FORC3 if (max < mul[c]) max = mul[c];
  FORC3 curvep[c] = foveon_make_curve (max, mul[c], filt);
}

int CLASS foveon_apply_curve (short *t_curve, int i)
{
  if (abs(i) >= t_curve[0]) return 0;
  return i < 0 ? -t_curve[1-i] : t_curve[1+i];
}

#ifdef LIBRAW_LIBRARY_BUILD
#ifdef image
#undef image
#endif
#define image ((short(*)[4]) imgdata.image)
#else
#define image ((short (*)[4]) image)
#endif

void CLASS foveon_interpolate()
{
  static const short hood[] = { -1,-1, -1,0, -1,1, 0,-1, 0,1, 1,-1, 1,0, 1,1 };
  short *pix, prev[3], *t_curve[8], (*t_shrink)[3];
  float cfilt=0, ddft[3][3][2], ppm[3][3][3];
  float cam_xyz[3][3], correct[3][3], last[3][3], trans[3][3];
  float chroma_dq[3], color_dq[3], diag[3][3], div[3];
  float (*t_black)[3], (*sgain)[3], (*sgrow)[3];
  float fsum[3], val, frow, num;
  int row, col, c, i, j, diff, sgx, irow, sum, min, max, limit;
  int dscr[2][2], dstb[4], (*smrow[7])[3], total[4], ipix[3];
  int work[3][3], smlast, smred, smred_p=0, dev[3];
  int satlev[3], keep[4], active[4];
  unsigned dim[3], *badpix;
  double dsum=0, trsum[3];
  char str[128];
  const char* cp;

  if (verbose)
    fprintf (stderr,_("Foveon interpolation...\n"));

  foveon_load_camf();
  foveon_fixed (dscr, 4, "DarkShieldColRange");
  foveon_fixed (ppm[0][0], 27, "PostPolyMatrix");
  foveon_fixed (satlev, 3, "SaturationLevel");
  foveon_fixed (keep, 4, "KeepImageArea");
  foveon_fixed (active, 4, "ActiveImageArea");
  foveon_fixed (chroma_dq, 3, "ChromaDQ");
  foveon_fixed (color_dq, 3,
	foveon_camf_param ("IncludeBlocks", "ColorDQ") ?
		"ColorDQ" : "ColorDQCamRGB");
  if (foveon_camf_param ("IncludeBlocks", "ColumnFilter"))
  		 foveon_fixed (&cfilt, 1, "ColumnFilter");

  memset (ddft, 0, sizeof ddft);
  if (!foveon_camf_param ("IncludeBlocks", "DarkDrift")
	 || !foveon_fixed (ddft[1][0], 12, "DarkDrift"))
    for (i=0; i < 2; i++) {
      foveon_fixed (dstb, 4, i ? "DarkShieldBottom":"DarkShieldTop");
      for (row = dstb[1]; row <= dstb[3]; row++)
	for (col = dstb[0]; col <= dstb[2]; col++)
	  FORC3 ddft[i+1][c][1] += (short) image[row*width+col][c];
      FORC3 ddft[i+1][c][1] /= (dstb[3]-dstb[1]+1) * (dstb[2]-dstb[0]+1);
    }

  if (!(cp = foveon_camf_param ("WhiteBalanceIlluminants", model2)))
  { fprintf (stderr,_("%s: Invalid white balance \"%s\"\n"), ifname, model2);
    return; }
  foveon_fixed (cam_xyz, 9, cp);
  foveon_fixed (correct, 9,
	foveon_camf_param ("WhiteBalanceCorrections", model2));
  memset (last, 0, sizeof last);
  for (i=0; i < 3; i++)
    for (j=0; j < 3; j++)
      FORC3 last[i][j] += correct[i][c] * cam_xyz[c][j];

  #define LAST(x,y) last[(i+x)%3][(c+y)%3]
  for (i=0; i < 3; i++)
    FORC3 diag[c][i] = LAST(1,1)*LAST(2,2) - LAST(1,2)*LAST(2,1);
  #undef LAST
  FORC3 div[c] = diag[c][0]*0.3127 + diag[c][1]*0.329 + diag[c][2]*0.3583;
  sprintf (str, "%sRGBNeutral", model2);
  if (foveon_camf_param ("IncludeBlocks", str))
    foveon_fixed (div, 3, str);
  num = 0;
  FORC3 if (num < div[c]) num = div[c];
  FORC3 div[c] /= num;

  memset (trans, 0, sizeof trans);
  for (i=0; i < 3; i++)
    for (j=0; j < 3; j++)
      FORC3 trans[i][j] += rgb_cam[i][c] * last[c][j] * div[j];
  FORC3 trsum[c] = trans[c][0] + trans[c][1] + trans[c][2];
  dsum = (6*trsum[0] + 11*trsum[1] + 3*trsum[2]) / 20;
  for (i=0; i < 3; i++)
    FORC3 last[i][c] = trans[i][c] * dsum / trsum[i];
  memset (trans, 0, sizeof trans);
  for (i=0; i < 3; i++)
    for (j=0; j < 3; j++)
      FORC3 trans[i][j] += (i==c ? 32 : -1) * last[c][j] / 30;

  foveon_make_curves (t_curve, color_dq, div, cfilt);
  FORC3 chroma_dq[c] /= 3;
  foveon_make_curves (t_curve+3, chroma_dq, div, cfilt);
  FORC3 dsum += chroma_dq[c] / div[c];
  t_curve[6] = foveon_make_curve (dsum, dsum, cfilt);
  t_curve[7] = foveon_make_curve (dsum*2, dsum*2, cfilt);

  sgain = (float (*)[3]) foveon_camf_matrix (dim, "SpatialGain");
  if (!sgain) return;
  sgrow = (float (*)[3]) calloc (dim[1], sizeof *sgrow);
  sgx = (width + dim[1]-2) / (dim[1]-1);

  t_black = (float (*)[3]) calloc (height, sizeof *t_black);
  for (row=0; row < height; row++) {
    for (i=0; i < 6; i++)
      ddft[0][0][i] = ddft[1][0][i] +
	row / (height-1.0) * (ddft[2][0][i] - ddft[1][0][i]);
    FORC3 t_black[row][c] =
 	( foveon_avg (image[row*width]+c, dscr[0], cfilt) +
	  foveon_avg (image[row*width]+c, dscr[1], cfilt) * 3
	  - ddft[0][c][0] ) / 4 - ddft[0][c][1];
  }
  memcpy (t_black, t_black+8, sizeof *t_black*8);
  memcpy (t_black+height-11, t_black+height-22, 11*sizeof *t_black);
  memcpy (last, t_black, sizeof last);

  for (row=1; row < height-1; row++) {
    FORC3 if (last[1][c] > last[0][c]) {
	if (last[1][c] > last[2][c])
	  t_black[row][c] = (last[0][c] > last[2][c]) ? last[0][c]:last[2][c];
      } else
	if (last[1][c] < last[2][c])
	  t_black[row][c] = (last[0][c] < last[2][c]) ? last[0][c]:last[2][c];
    memmove (last, last+1, 2*sizeof last[0]);
    memcpy (last[2], t_black[row+1], sizeof last[2]);
  }
  FORC3 t_black[row][c] = (last[0][c] + last[1][c])/2;
  FORC3 t_black[0][c] = (t_black[1][c] + t_black[3][c])/2;

  val = 1 - exp(-1/24.0);
  memcpy (fsum, t_black, sizeof fsum);
  for (row=1; row < height; row++)
    FORC3 fsum[c] += t_black[row][c] =
	(t_black[row][c] - t_black[row-1][c])*val + t_black[row-1][c];
  memcpy (last[0], t_black[height-1], sizeof last[0]);
  FORC3 fsum[c] /= height;
  for (row = height; row--; )
    FORC3 last[0][c] = t_black[row][c] =
	(t_black[row][c] - fsum[c] - last[0][c])*val + last[0][c];

  memset (total, 0, sizeof total);
  for (row=2; row < height; row+=4)
    for (col=2; col < width; col+=4) {
      FORC3 total[c] += (short) image[row*width+col][c];
      total[3]++;
    }
  for (row=0; row < height; row++)
    FORC3 t_black[row][c] += fsum[c]/2 + total[c]/(total[3]*100.0);

  for (row=0; row < height; row++) {
    for (i=0; i < 6; i++)
      ddft[0][0][i] = ddft[1][0][i] +
	row / (height-1.0) * (ddft[2][0][i] - ddft[1][0][i]);
    pix = image[row*width];
    memcpy (prev, pix, sizeof prev);
    frow = row / (height-1.0) * (dim[2]-1);
    if ((irow = frow) == dim[2]-1) irow--;
    frow -= irow;
    for (i=0; i < dim[1]; i++)
      FORC3 sgrow[i][c] = sgain[ irow   *dim[1]+i][c] * (1-frow) +
			  sgain[(irow+1)*dim[1]+i][c] *    frow;
    for (col=0; col < width; col++) {
      FORC3 {
	diff = pix[c] - prev[c];
	prev[c] = pix[c];
	ipix[c] = pix[c] + floor ((diff + (diff*diff >> 14)) * cfilt
		- ddft[0][c][1] - ddft[0][c][0] * ((float) col/width - 0.5)
		- t_black[row][c] );
      }
      FORC3 {
	work[0][c] = ipix[c] * ipix[c] >> 14;
	work[2][c] = ipix[c] * work[0][c] >> 14;
	work[1][2-c] = ipix[(c+1) % 3] * ipix[(c+2) % 3] >> 14;
      }
      FORC3 {
	for (val=i=0; i < 3; i++)
	  for (  j=0; j < 3; j++)
	    val += ppm[c][i][j] * work[i][j];
	ipix[c] = floor ((ipix[c] + floor(val)) *
		( sgrow[col/sgx  ][c] * (sgx - col%sgx) +
		  sgrow[col/sgx+1][c] * (col%sgx) ) / sgx / div[c]);
	if (ipix[c] > 32000) ipix[c] = 32000;
	pix[c] = ipix[c];
      }
      pix += 4;
    }
  }
  free (t_black);
  free (sgrow);
  free (sgain);

  if ((badpix = (unsigned int *) foveon_camf_matrix (dim, "BadPixels"))) {
    for (i=0; i < dim[0]; i++) {
      col = (badpix[i] >> 8 & 0xfff) - keep[0];
      row = (badpix[i] >> 20       ) - keep[1];
      if ((unsigned)(row-1) > height-3 || (unsigned)(col-1) > width-3)
	continue;
      memset (fsum, 0, sizeof fsum);
      for (sum=j=0; j < 8; j++)
	if (badpix[i] & (1 << j)) {
	  FORC3 fsum[c] += (short)
		image[(row+hood[j*2])*width+col+hood[j*2+1]][c];
	  sum++;
	}
      if (sum) FORC3 image[row*width+col][c] = fsum[c]/sum;
    }
    free (badpix);
  }

  /* Array for 5x5 Gaussian averaging of red values */
  smrow[6] = (int (*)[3]) calloc (width*5, sizeof **smrow);
  merror (smrow[6], "foveon_interpolate()");
  for (i=0; i < 5; i++)
    smrow[i] = smrow[6] + i*width;

  /* Sharpen the reds against these Gaussian averages */
  for (smlast=-1, row=2; row < height-2; row++) {
    while (smlast < row+2) {
      for (i=0; i < 6; i++)
	smrow[(i+5) % 6] = smrow[i];
      pix = image[++smlast*width+2];
      for (col=2; col < width-2; col++) {
	smrow[4][col][0] =
	  (pix[0]*6 + (pix[-4]+pix[4])*4 + pix[-8]+pix[8] + 8) >> 4;
	pix += 4;
      }
    }
    pix = image[row*width+2];
    for (col=2; col < width-2; col++) {
      smred = ( 6 *  smrow[2][col][0]
	      + 4 * (smrow[1][col][0] + smrow[3][col][0])
	      +      smrow[0][col][0] + smrow[4][col][0] + 8 ) >> 4;
      if (col == 2)
	smred_p = smred;
      i = pix[0] + ((pix[0] - ((smred*7 + smred_p) >> 3)) >> 3);
      if (i > 32000) i = 32000;
      pix[0] = i;
      smred_p = smred;
      pix += 4;
    }
  }

  /* Adjust the brighter pixels for better linearity */
  min = 0xffff;
  FORC3 {
    i = satlev[c] / div[c];
    if (min > i) min = i;
  }
  limit = min * 9 >> 4;
  for (pix=image[0]; pix < image[height*width]; pix+=4) {
    if (pix[0] <= limit || pix[1] <= limit || pix[2] <= limit)
      continue;
    min = max = pix[0];
    for (c=1; c < 3; c++) {
      if (min > pix[c]) min = pix[c];
      if (max < pix[c]) max = pix[c];
    }
    if (min >= limit*2) {
      pix[0] = pix[1] = pix[2] = max;
    } else {
      i = 0x4000 - ((min - limit) << 14) / limit;
      i = 0x4000 - (i*i >> 14);
      i = i*i >> 14;
      FORC3 pix[c] += (max - pix[c]) * i >> 14;
    }
  }
/*
   Because photons that miss one detector often hit another,
   the sum R+G+B is much less noisy than the individual colors.
   So smooth the hues without smoothing the total.
 */
  for (smlast=-1, row=2; row < height-2; row++) {
    while (smlast < row+2) {
      for (i=0; i < 6; i++)
	smrow[(i+5) % 6] = smrow[i];
      pix = image[++smlast*width+2];
      for (col=2; col < width-2; col++) {
	FORC3 smrow[4][col][c] = (pix[c-4]+2*pix[c]+pix[c+4]+2) >> 2;
	pix += 4;
      }
    }
    pix = image[row*width+2];
    for (col=2; col < width-2; col++) {
      FORC3 dev[c] = -foveon_apply_curve (t_curve[7], pix[c] -
	((smrow[1][col][c] + 2*smrow[2][col][c] + smrow[3][col][c]) >> 2));
      sum = (dev[0] + dev[1] + dev[2]) >> 3;
      FORC3 pix[c] += dev[c] - sum;
      pix += 4;
    }
  }
  for (smlast=-1, row=2; row < height-2; row++) {
    while (smlast < row+2) {
      for (i=0; i < 6; i++)
	smrow[(i+5) % 6] = smrow[i];
      pix = image[++smlast*width+2];
      for (col=2; col < width-2; col++) {
	FORC3 smrow[4][col][c] =
		(pix[c-8]+pix[c-4]+pix[c]+pix[c+4]+pix[c+8]+2) >> 2;
	pix += 4;
      }
    }
    pix = image[row*width+2];
    for (col=2; col < width-2; col++) {
      for (total[3]=375, sum=60, c=0; c < 3; c++) {
	for (total[c]=i=0; i < 5; i++)
	  total[c] += smrow[i][col][c];
	total[3] += total[c];
	sum += pix[c];
      }
      if (sum < 0) sum = 0;
      j = total[3] > 375 ? (sum << 16) / total[3] : sum * 174;
      FORC3 pix[c] += foveon_apply_curve (t_curve[6],
		((j*total[c] + 0x8000) >> 16) - pix[c]);
      pix += 4;
    }
  }

  /* Transform the image to a different colorspace */
  for (pix=image[0]; pix < image[height*width]; pix+=4) {
    FORC3 pix[c] -= foveon_apply_curve (t_curve[c], pix[c]);
    sum = (pix[0]+pix[1]+pix[1]+pix[2]) >> 2;
    FORC3 pix[c] -= foveon_apply_curve (t_curve[c], pix[c]-sum);
    FORC3 {
      for (dsum=i=0; i < 3; i++)
	dsum += trans[c][i] * pix[i];
      if (dsum < 0)  dsum = 0;
      if (dsum > 24000) dsum = 24000;
      ipix[c] = dsum + 0.5;
    }
    FORC3 pix[c] = ipix[c];
  }

  /* Smooth the image bottom-to-top and save at 1/4 scale */
  t_shrink = (short (*)[3]) calloc ((width/4) * (height/4), sizeof *t_shrink);
  merror (t_shrink, "foveon_interpolate()");
  for (row = height/4; row--; )
    for (col=0; col < width/4; col++) {
      ipix[0] = ipix[1] = ipix[2] = 0;
      for (i=0; i < 4; i++)
	for (j=0; j < 4; j++)
	  FORC3 ipix[c] += image[(row*4+i)*width+col*4+j][c];
      FORC3
	if (row+2 > height/4)
	  t_shrink[row*(width/4)+col][c] = ipix[c] >> 4;
	else
	  t_shrink[row*(width/4)+col][c] =
	    (t_shrink[(row+1)*(width/4)+col][c]*1840 + ipix[c]*141 + 2048) >> 12;
    }
  /* From the 1/4-scale image, smooth right-to-left */
  for (row=0; row < (height & ~3); row++) {
    ipix[0] = ipix[1] = ipix[2] = 0;
    if ((row & 3) == 0)
      for (col = width & ~3 ; col--; )
	FORC3 smrow[0][col][c] = ipix[c] =
	  (t_shrink[(row/4)*(width/4)+col/4][c]*1485 + ipix[c]*6707 + 4096) >> 13;

  /* Then smooth left-to-right */
    ipix[0] = ipix[1] = ipix[2] = 0;
    for (col=0; col < (width & ~3); col++)
      FORC3 smrow[1][col][c] = ipix[c] =
	(smrow[0][col][c]*1485 + ipix[c]*6707 + 4096) >> 13;

  /* Smooth top-to-bottom */
    if (row == 0)
      memcpy (smrow[2], smrow[1], sizeof **smrow * width);
    else
      for (col=0; col < (width & ~3); col++)
	FORC3 smrow[2][col][c] =
	  (smrow[2][col][c]*6707 + smrow[1][col][c]*1485 + 4096) >> 13;

  /* Adjust the chroma toward the smooth values */
    for (col=0; col < (width & ~3); col++) {
      for (i=j=30, c=0; c < 3; c++) {
	i += smrow[2][col][c];
	j += image[row*width+col][c];
      }
      j = (j << 16) / i;
      for (sum=c=0; c < 3; c++) {
	ipix[c] = foveon_apply_curve (t_curve[c+3],
	  ((smrow[2][col][c] * j + 0x8000) >> 16) - image[row*width+col][c]);
	sum += ipix[c];
      }
      sum >>= 3;
      FORC3 {
	i = image[row*width+col][c] + ipix[c] - sum;
	if (i < 0) i = 0;
	image[row*width+col][c] = i;
      }
    }
  }
  free (t_shrink);
  free (smrow[6]);
  for (i=0; i < 8; i++)
    free (t_curve[i]);

  /* Trim off the black border */
  if (~cropbox[2] && ~cropbox[3])
    {
      // Image already cropped, do nothing
      int crop[4],c;
      for(int c=0;c<4;c++) 
        {
          crop[c] = cropbox[c];
          if(crop[c]<0)
            crop[c]=0;
        }
      if(crop[0]>=width-1) crop[0] = width - 2;
      if(crop[1]>=height-1) crop[1] = height-2;
      if(crop[0]+crop[2] >= width) crop[2] = width-crop[0];
      if(crop[1]+crop[3] >= height) crop[3] = height-crop[1];
      active[0] = crop[0];
      active[1] = crop[1];
      active[2] = crop[0]+crop[2];
      active[3] = crop[1]+crop[3];
    }
  else
    {
      active[1] -= keep[1];
      active[3] -= 2;
    }
  i = active[2] - active[0];
  for (row=0; row < active[3]-active[1]; row++)
    memcpy (image[row*i], image[(row+active[1])*width+active[0]],
            i * sizeof *image);
  width = i;
  height = row;

}
#undef image
#ifdef LIBRAW_LIBRARY_BUILD
#define image           (imgdata.image)
#endif

/* RESTRICTED code ends here */