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### implementation algorithm

Dear all,

I have a question for cvFlip function in C. I implemented horizontal cvflip function algorithm. But, the problem is that the speed is slower than using dll file from opencv. I just implemented same algorithm and did not use function call.

Could any one explain this? The implementation is for( ii = 0; ii < ROIWidth3; ii++ ) for( kk = 0; kk < 2; kk++ ) tab[ii2 + kk] = (int)((ROIWidth3 - ii - 1)2 + kk); for( ; ll < ROIHeight3; ll++, imageArray3+= ROIWidth32, imageArray3_1+= ROIWidth32) { for( ii = 0; ii < (int)(ROIWidth3 + 1); ii++ ) { jj = tab[ii]; temp3 = imageArray3[ii], temp31 = imageArray3[jj]; imageArray3_1[ii] = temp31; imageArray3_1[jj] = temp3; } }

imageArray3_1 -= ROIHeight3ROIWidth3; imageArray3 -= ROIHeight3ROIWidth3;

Sincerely, Taiyoon Lee

 2 No.2 Revision StevenPuttemans 19874 ●14 ●82 ●205 http://stevenputtemans...

### implementation algorithm

Dear all,

I have a question for cvFlip function in C. I implemented horizontal cvflip cvFlip function algorithm. But, the problem is that the speed is slower than using dll file from opencv. I just implemented same algorithm and did not use function call.

Could any one explain this? The implementation is

for( ii = 0; ii < ROIWidth3; ii++ ) for( kk = 0; kk < 2; kk++ )
tab[ii2 + kk] = (int)((ROIWidth3 - ii - 1)2 + kk);
for( ; ll < ROIHeight3; ll++, imageArray3+= ROIWidth32, imageArray3_1+= ROIWidth32) {
for( ii = 0; ii < (int)(ROIWidth3 + 1); ii++ ) { jj = tab[ii]; temp3 = imageArray3[ii], temp31 = imageArray3[jj]; imageArray3_1[ii] = temp31; imageArray3_1[jj] = temp3; } }}
imageArray3_1 -= ROIHeight3ROIWidth3;
imageArray3 -= ROIHeight3ROIWidth3;ROIHeight3ROIWidth3;


Sincerely, Taiyoon Lee