thresholdtrans.asm

来自「DSP学习讲座」· 汇编 代码 · 共 46 行

k_threshold  .set 128;设定域值
k_white      .set 255
k_black      .set 0
             .data
output       .space 0x10000;分配输出空间
input        .copy Lenna;拷贝图像数据
bos          .usect"stack",8
             .text
             .def thres_int
             .def end
             .def thresholdtrans
thres_int:        
             mvk  k_threshold,a2
             mvk  k_white,a3
             mvk  k_black,a4
             mvkl input,b2
             mvkh input,b2
             mvkl output,b3
             mvkh output,b3
             mvkl 65535,b0
             mvkh 65535,b0
thresholdtrans:  
             ldbu *b2++,a5
             nop  
             nop
             nop
             nop
             nop
             ;cmpgtu a5,a2,a6
             cmpltu a5,a2,a6;灰度变换
             mpyu a6,a3,a7
             nop
             stb  a7,*b3++ 
             sub  b0,1,b0            
         [b0]b    thresholdtrans
             nop  
             nop
             nop
             nop
             nop
end:         b    end
             nop 5
             .end