/* Colorize()
 *
 * Pseudo-colorizes FFT Spectrum Display pixels
 * according to the IFFT's output bin values
 */
  void
Colorize( guchar *pix, int pixel_val )
{
  // Color palette (Viridis colormap)
  static const uint8_t
    R[256] = {
       68,  68,  69,  69,  69,  70,  70,  70,
       70,  71,  71,  71,  71,  71,  72,  72,
       72,  72,  72,  72,  72,  72,  72,  72,
       72,  72,  72,  72,  72,  71,  71,  71,
       71,  71,  70,  70,  70,  70,  69,  69,
       69,  68,  68,  68,  67,  67,  67,  66,
       66,  65,  65,  65,  64,  64,  63,  63,
       62,  62,  61,  61,  60,  60,  59,  59,
       58,  58,  57,  57,  56,  56,  55,  55,
       54,  54,  53,  53,  52,  52,  51,  51,
       51,  50,  50,  49,  49,  48,  48,  47,
       47,  47,  46,  46,  45,  45,  45,  44,
       44,  43,  43,  43,  42,  42,  41,  41,
       41,  40,  40,  40,  39,  39,  38,  38,
       38,  37,  37,  37,  36,  36,  35,  35,
       35,  34,  34,  34,  33,  33,  33,  32,
       32,  32,  32,  31,  31,  31,  31,  31,
       30,  30,  30,  30,  30,  30,  30,  30,
       30,  31,  31,  31,  31,  32,  32,  33,
       33,  34,  35,  35,  36,  37,  38,  39,
       40,  41,  42,  43,  44,  46,  47,  48,
       50,  51,  53,  54,  56,  57,  59,  61,
       62,  64,  66,  68,  70,  72,  73,  75,
       77,  79,  81,  83,  85,  88,  90,  92,
       94,  96,  98, 101, 103, 105, 108, 110,
      112, 115, 117, 119, 122, 124, 127, 129,
      132, 134, 137, 139, 142, 144, 147, 149,
      152, 155, 157, 160, 163, 165, 168, 171,
      173, 176, 179, 181, 184, 187, 189, 192,
      195, 197, 200, 203, 205, 208, 211, 213,
      216, 219, 221, 224, 226, 229, 232, 234,
      237, 239, 242, 244, 247, 249, 251, 254
    },
    G[256] = {
        1,   2,   3,   5,   6,   8,   9,  11,
       12,  14,  15,  17,  18,  20,  21,  22,
       24,  25,  26,  28,  29,  30,  32,  33,
       34,  36,  37,  38,  39,  41,  42,  43,
       44,  46,  47,  48,  49,  51,  52,  53,
       54,  56,  57,  58,  59,  60,  62,  63,
       64,  65,  66,  67,  69,  70,  71,  72,
       73,  74,  75,  77,  78,  79,  80,  81,
       82,  83,  84,  85,  86,  87,  88,  89,
       91,  92,  93,  94,  95,  96,  97,  98,
       99, 100, 101, 102, 103, 104, 105, 106,
      107, 108, 109, 110, 111, 112, 112, 113,
      114, 115, 116, 117, 118, 119, 120, 121,
      122, 123, 124, 125, 126, 127, 128, 129,
      130, 131, 131, 132, 133, 134, 135, 136,
      137, 138, 139, 140, 141, 142, 143, 144,
      145, 146, 147, 147, 148, 149, 150, 151,
      152, 153, 154, 155, 156, 157, 158, 159,
      160, 161, 162, 163, 163, 164, 165, 166,
      167, 168, 169, 170, 171, 172, 173, 174,
      175, 175, 176, 177, 178, 179, 180, 181,
      182, 183, 183, 184, 185, 186, 187, 188,
      189, 190, 190, 191, 192, 193, 194, 194,
      195, 196, 197, 198, 198, 199, 200, 201,
      201, 202, 203, 204, 204, 205, 206, 206,
      207, 208, 208, 209, 210, 210, 211, 212,
      212, 213, 213, 214, 215, 215, 216, 216,
      217, 217, 218, 218, 219, 219, 220, 220,
      221, 221, 221, 222, 222, 223, 223, 223,
      224, 224, 225, 225, 225, 226, 226, 226,
      227, 227, 227, 228, 228, 228, 229, 229,
      229, 230, 230, 230, 230, 231, 231, 231
    },
    B[256] = {
       84,  85,  87,  88,  90,  91,  93,  94,
       96,  97,  98, 100, 101, 102, 104, 105,
      106, 108, 109, 110, 111, 112, 113, 115,
      116, 117, 118, 119, 120, 121, 121, 122,
      123, 124, 125, 126, 126, 127, 128, 129,
      129, 130, 131, 131, 132, 132, 133, 133,
      134, 134, 135, 135, 136, 136, 136, 137,
      137, 137, 138, 138, 138, 138, 139, 139,
      139, 139, 140, 140, 140, 140, 140, 140,
      141, 141, 141, 141, 141, 141, 141, 141,
      141, 142, 142, 142, 142, 142, 142, 142,
      142, 142, 142, 142, 142, 142, 142, 142,
      142, 142, 142, 142, 142, 142, 142, 142,
      142, 142, 142, 142, 142, 142, 142, 142,
      142, 142, 142, 142, 142, 142, 142, 142,
      142, 141, 141, 141, 141, 141, 141, 141,
      140, 140, 140, 140, 140, 139, 139, 139,
      139, 138, 138, 138, 137, 137, 137, 136,
      136, 136, 135, 135, 134, 134, 134, 133,
      133, 132, 131, 131, 130, 130, 129, 129,
      128, 127, 127, 126, 125, 124, 124, 123,
      122, 121, 121, 120, 119, 118, 117, 116,
      115, 114, 113, 112, 111, 110, 109, 108,
      107, 106, 105, 104, 102, 101, 100,  99,
       98,  96,  95,  94,  92,  91,  90,  88,
       87,  85,  84,  82,  81,  79,  78,  76,
       75,  73,  72,  70,  68,  67,  65,  63,
       62,  60,  58,  57,  55,  53,  51,  50,
       48,  46,  45,  43,  41,  39,  38,  36,
       35,  33,  32,  30,  29,  28,  27,  26,
       25,  24,  24,  24,  24,  24,  25,  25,
       26,  27,  28,  30,  31,  33,  35,  36
    };

  // Enter the palette to the pixmap
  pix[0] = R[pixel_val];
  pix[1] = G[pixel_val];
  pix[2] = B[pixel_val];

} // Colorize()

