# Revision history [back]

### Optimizing split/merge for clahe

Hi,

I am trying to squeeze the last ms from a tracking loop. One of the time consuminig parts is doing adaptive contrast enhancement (clahe), which is a necessary part. The results are great, but I am wondering whether I could avoid some copying/splitting/merge or apply other optimizations.

Basically I do the following in tight loop:

cv::cvtColor(rgb, hsv, cv::COLOR_BGR2HSV);
std::vector<cv::Mat> hsvChannels;
cv::split(hsv, hsvChannels);
m_clahe->apply(hsvChannels[2], hsvChannels[2]); /* m_clahe constructed outside loop */
cv::merge(hsvChannels, hsvOut);
cv::cvtColor(hsvOut, rgbOut, cv::COLOR_HSV2BGR);


On the test machine, the above snippet takes about 8ms (on 1Mpix images), The actual clahe part takes only 1-2 ms.

 2 retagged sturkmen 6021 ●3 ●42 ●69 https://github.com/stu...

### Optimizing split/merge for clahe

Hi,

I am trying to squeeze the last ms from a tracking loop. One of the time consuminig parts is doing adaptive contrast enhancement (clahe), which is a necessary part. The results are great, but I am wondering whether I could avoid some copying/splitting/merge or apply other optimizations.

Basically I do the following in tight loop:

cv::cvtColor(rgb, hsv, cv::COLOR_BGR2HSV);
std::vector<cv::Mat> hsvChannels;
cv::split(hsv, hsvChannels);
m_clahe->apply(hsvChannels[2], hsvChannels[2]); /* m_clahe constructed outside loop */
cv::merge(hsvChannels, hsvOut);
cv::cvtColor(hsvOut, rgbOut, cv::COLOR_HSV2BGR);


On the test machine, the above snippet takes about 8ms (on 1Mpix images), The actual clahe part takes only 1-2 ms.

 3 retagged sturkmen 6021 ●3 ●42 ●69 https://github.com/stu...

### Optimizing split/merge for clahe

Hi,

I am trying to squeeze the last ms from a tracking loop. One of the time consuminig parts is doing adaptive contrast enhancement (clahe), which is a necessary part. The results are great, but I am wondering whether I could avoid some copying/splitting/merge or apply other optimizations.

Basically I do the following in tight loop:

cv::cvtColor(rgb, hsv, cv::COLOR_BGR2HSV);
std::vector<cv::Mat> hsvChannels;
cv::split(hsv, hsvChannels);
m_clahe->apply(hsvChannels[2], hsvChannels[2]); /* m_clahe constructed outside loop */
cv::merge(hsvChannels, hsvOut);
cv::cvtColor(hsvOut, rgbOut, cv::COLOR_HSV2BGR);


On the test machine, the above snippet takes about 8ms (on 1Mpix images), The actual clahe part takes only 1-2 ms.