C++ Dereferencing char-Pointer (image array) is very slow -

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i have trouble getting fast access unsigned character array.

i want copy bgrabgra....bgrabgra.... linewise coded image array opencv-version uses 3 layers. code below works fine slow (around 0.5 seconds 640*480 image). pointed out dereferencing operator * makes slow. have plan how fix this? (hint: byte unsigned char)

// run thorugh pixels , copy image data (int y = 0; y<imheight; y++){     byte* pline= vrim->mp_buffer + y * vrim->m_pitch;     (int x = 0; x<imwidth; x++){         byte* b= pline++; // fast pointer operation         byte* g= pline++;         byte* r= pline++;         byte* a= pline++; // (alpha)         byte bc = *b; // slow!         byte gc = *g; // slow!         byte rc = *r; // slow!      } }

thanks!

shouldn't - there no way taking 0.5sec 640x480 unless doing on 8086. there other code aren't showing? destination memory doesn't go anywhere

ps take @ cvcvtcolor() uses optimized sse2/simd instructions


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