DoubangoTelecom / compv

Insanely fast Open Source Computer Vision library for ARM and x86 devices (Up to #50 times faster than OpenCV)
https://doubango.org
GNU General Public License v3.0
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Sobel could be done multiplication-free #127

Open DoubangoTelecom opened 7 years ago

DoubangoTelecom commented 7 years ago

Sobel kernels are pre-defined (0, 1 and 2 values) which means we can compute the convolution without using multiplications (add and sub only). For now sobel convolution not used in commercial products which means not urgent to change the implementaion.

DoubangoTelecom commented 7 years ago

And use abs_avg ((abs(gx) + abs(gy) + 1) >> 1) instead of gradient L1 plus scaleAndClip. abs_avg is single instruction in SSE and NEON