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��߹��ʬ�ϡ��ʿ��(running average)��ͤ��򤷤䤹�� Ǥ��礦��ʿ�Ѥϥǡ��ʿ�Ѥ�׻��򤺤餷�ʤ��ʿ��ͤ� ��Ƥ��ȤǤ��ޤ��ʷ��Ĥ��⤦�Ȥ��ΤǤ��

��ơ��η׻��򣲼��Υǡ��¤��Ĳ��ǡ��Ŭ�Ѥ�� 櫓�Ǥ��η׻��Ԥ��ġ��Ȥ��ơ�pnmconvol�Ȥ�� ޥ�ɤ��ޤ��man pnmconvol��ɤ�Ȥ狼��ޤ� ��Υ��ޥ�ɤλ��ѤˤϤ��ʤ��դ�ɬ�פǤ��

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�ʲ�� 3 x 3 ��ΰ��ʿ�Ѳ��򸫤Ƥ��

��Ǥϡ��ͤ�18�Ǥ��顢��ͤ�Ⱦʬ�� 9 �� 0 ��ޤ�� Ǥ��顢�ǡ�� 10 �ϡ�1 ��ޤ��ޤ��˻Ȥ�� 9 �Ǥ��顢��줾��Υǡ��ͤ� 1/9 �νŤߤ��äƤ��뤳�Ȥ� �ʤ�ޤ��⤷��5x5 ��ʿ�Ѥ򤷤��С��ͤ� 5x5x2 = 50��ǡ�� ͤȤ��Ƥϡ�25+1 �� 26 ��Ȥ��Ф褤��Ȥ��狼��ޤ��

��ޥ�ɤμ¹Ԥϡ��̲�ե��륿��ξ��߹��ߴؿ��ե�� lpf.pgm �Ȥ��Ȥ��

        % pnmconvol lpf.pgm johoto.pgm > joho-lpf.pgm

�Τ褦�ˤ��ޤ�� 5x5 ��ñ��ʿ�Ѥ򤫤��ʲ��β��˼��ޤ��

��̲�ե��륿��Ǥ��β��顢��̲�ե��륿�� ̤��򺹤��й��̲�ե��륿��Ǥ��ޤ��5x5�ι��̲�ե��륿�� Ǥ��(��ɽ�ϥ��ե��åȤ��ͤǤ�)

        P2
        5 5
        50
        24 24 24 24 24    -1 -1 -1 -1 -1
        24 24 24 24 24    -1 -1 -1 -1 -1
        24 24 49 24 24    -1 -1 24 -1 -1
        24 24 24 24 24    -1 -1 -1 -1 -1
        24 24 24 24 24    -1 -1 -1 -1 -1

��ǤϾ��߹��ʬ�μ¹Ԥ��η׻��̤� 0 �˴ݤ��Ƥ��ޤ��Ȥ� ��դ��Ƥ��ʲ��η�̤β��ϡ��̤򸫤䤹��뤿�� ͤ� 10 �ˤ��Ƥ��ޤ��

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        P2
        3 3
        2
        1 2 1            0  1  0
        0 1 2           -1  0  1
        1 0 1            0 -1  0

�Τ褦�ʥե��륿��Ȥ��ȡ��ϱ��夫�麸��ؤ��ʬ��ɽ�� Ȥˤʤ�ޤ��Υե��륿��Ŭ�Ѥ��̤ϰʲ��ΤȤ��Ǥ��

��Τ褦��оΥե��륿��ϥ��å��θ��Ф˻Ȥ��뤳�Ȥ��ޤ�� 褯�Ȥ��ΤΤҤȤĤ� Sobel �Υ��ڥ졼��ȸƤФ��Τ��ޤ�� x ��y��Υ��å��θ��Фˡ��줾��ʲ��Τ褦�ʥե��륿�� Ѥ��ޤ��

          -1  0  1         -1 -2 -1
       X: -2  0  2      Y:  0  0  0
          -1  0  1          1  2  1

��̤ϰʲ��Τ褦�ˤʤ�ޤ��줾�� x,y ��Ȥ館�Ƥ�� Ȥ��狼��Ȼפ��ޤ��

�ºݤΥ��å��Фˤϵ��ʬ��ɬ�פǤ��pnmconvol ��Ȥä� ��η׻��Ԥ��Τ��ѻ��ˤʤ�ޤ��pgmedge �Ȥ��ޥ�ɤ� x y �� Sobel �Υ��ڥ졼��ȤäƤ��2��¤��Ϥ��ޤ�� ʲ��¹��Ǥ��

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