bin_a1.rcd

来自「JPEG Image compression using IJG standar」· RCD 代码 · 共 93 行

[jliang@xian binJPEG]$ ./cjpeg -quality 100 -dct bin_a1 img88.pgm > img88_bin_a1.jpg

Original image:
        52        55        61        66        70        61        64        73
        63        59        66        90       109        85        69        72
        62        59        68       113       144       104        66        73
        63        58        71       122       154       106        70        69
        67        61        68       104       126        88        68        70
        79        65        60        70        77        68        58        75
        85        71        64        59        55        61        65        83
        87        79        69        68        65        76        78        94
After forward DCT: ( TrueDCT * 4 * S)
     -3312      -158      -322       116       221      -142        -8         9
       -38       -55      -158        12        20       -23       -26        22
      -238        28       256       -78       -77        50        31       -16
      -130         4        11       -20        -5         9        -2        11
        43       -22       -32        -4        -1         5       -15         5
       -87        15        38       -18        -6        10        13        -2
       -23        -3        12        -5         1       -17        11       -13
      -115        31        96       -30       -20        19         8        -2

After quantization: trueDCT/Q0)
      -414       -26       -64        23        55       -20        -1         2
        -6       -14       -40         4         7        -5        -7         6
       -48         7        85       -26       -26        13         8        -4
       -26         1         4        -7        -3         2        -1         4
        11        -7       -11        -2        -1         2        -5         2
       -12         3        10        -5        -2         2         3         0
        -4        -1         3        -1         0        -3         2        -3
       -19         8        24       -10        -7         4         2        -1
---------------------------------------------------------------------------------
Float result:
After forward DCT:(This is trueDCT * (Scale * 8)
  -3312.00   -322.96   -647.44    238.30    438.00   -123.92     -2.56      4.59
     67.49   -316.86   -893.56    104.53    127.92    -57.90    -38.57     20.75
   -481.76    115.34   1047.84   -314.57   -309.98     83.26     36.14    -13.77
   -460.14    153.58    421.64   -157.44    -92.76     45.76      6.80      3.89
     86.00    -84.71   -130.15    -19.23     -4.00      8.59    -19.85      3.35
    -60.60     12.27     28.02    -24.35     -2.96      2.05      6.16     -0.68
    -12.24     -7.38      7.86      0.39      3.98    -11.96      4.16     -3.31
     -2.75     -2.17     -1.40     -6.99     -0.20     -0.69     -1.09      0.25

After quantization:(With Qfactor=50: divide by Q0 and 8Scale: get trueDCT/Q0)
      -414       -29       -62        25        55       -20        -1         2
         6       -21       -62         8        12        -7        -6         7
       -46         8        77       -26       -30        10         6        -5
       -49        12        34       -14       -10         6         1         1
        11        -8       -12        -2         0         1        -5         2
       -10         1         3        -3         0         0         2         0
        -3        -1         1         0         1        -4         2        -3
        -1        -1         0        -3         0         0        -1         0

-----------------------------------------------------------------------------------
[jliang@xian binJPEG]$ ./djpeg -dct bin_a1 img88_bin_a1.jpg > img88_bin_a1_rec.pgm     
     -3312       -36      -240      -130        44       -84       -24      -114
      -156       -56        28         3       -21        15        -4        32
      -320      -160       255        12       -33        40        12        96
       115        12       -78       -21        -4       -20        -4       -30
       220        21       -78        -6        -2        -6         0       -21
      -140       -25        52         8         6        12       -15        20
        -6       -28        32        -4       -15        15        10         8
        12        24       -16        12         6         0       -12        -4

After inverse DCT:
        52        60        64        54        58        63        64        67
        44        73        82        84       104       102        88        59
        47        79        86        82       102       109        86        57
        42        85        95        89       120       129        91        42
        51        82        86        76        98       106        83        49
        49        79        85        79        98       105        85        57
        76        75        72        61        57        69        76        79
        89        82        69        58        53        76        75        90
[jliang@xian bi
org:
        52        55        61        66        70        61        64        73
        63        59        66        90       109        85        69        72
        62        59        68       113       144       104        66        73
        63        58        71       122       154       106        70        69
        67        61        68       104       126        88        68        70
        79        65        60        70        77        68        58        75
        85        71        64        59        55        61        65        83
        87        79        69        68        65        76        78        94

Error: RecImg - OrgImg 
         0         5         3       -12       -12         2         0        -6
       -19        14        16        -6        -5        17        19       -13
       -15        20        18       -31       -42         5        20       -16
       -21        27        24       -33       -34        23        21       -27
       -16        21        18       -28       -28        18        15       -21
       -30        14        25         9        21        37        27       -18
        -9         4         8         2         2         8        11        -4
         2         3         0       -10       -12         0        -3        -4