API Utilities

Utilities

← Back to API Reference · Home

cropRect

Copy a rectangular region between two buffers; supports inplace stride reduction.

Namespace: acl::memory

template<class T>
int cropRect(
    const T* srcBuffer, T* dstBuffer,
    int copyWidth, int copyHeight,
    int srcStride = 0, int dstStride = 0,
    int srcLeft = 0, int srcTop = 0,
    int dstLeft = 0, int dstTop = 0);

Parameter	Type	Meaning	Default
copyWidth, copyHeight	int	Size of the region to copy	—
srcLeft, srcTop	int	Starting position in the source buffer	0
dstLeft, dstTop	int	Starting position in the destination buffer	0
srcStride, dstStride	int	Bytes per row	0 = auto

Supports inplace stride reduction when srcBuffer == dstBuffer (compresses in place when srcStride ≥ dstStride).

Namespace Availability Matrix

Per-category distribution across acl::neon::* and the scalar CPP path (acl::{module}::*). When an operator exists in both, the signatures are identical unless the operator's own section calls out a difference.

Category	Both neon:: + CPP	CPP only
Analysis	integral, histogram, equalizeHist, clahe, minMaxLoc, copyMakeBorder, matchTemplate, blockAverage	histMatch, moments, count, mean, connectedComponent_8n_dfs, connectedComponentLabeling, findContours, distanceTransform, extractBlockPixels
Arithmetic	addImg, absDiff, addWeighted, alphaImgFusion, mul, threshold, adaptiveThreshold, bitwise (And/Not/Xor), lut, convertScaleAbs, inRange, normalize, phaseMagnitude	linearTransform2x2
Color Conversion	RGB2Gray / RGBA2Gray, channelSwap (5 Mode tags), bayer2RGB, rgb2YUV_fixed family, yuv2RGB_fixed family, rgb2HSV / bgr2HSV, rgb2Lab / bgr2Lab	hsv2BGR, lab2BGR, rgb2YUV_float family, yuv2RGB_float family, bayer2RGBA, gammaTransform
Filter	gaussianBlur, boxFilter, filter2D, sepFilter2D, sobel3x3, scharr, laplacian, morphology (erode/dilate), canny, medianFilter3x3, bilateralFilter, nlMeansDenoising, guidedFilter, unsharpMask, stackBlur, gaborFilter	edgePreservingFilter, detailEnhance, tonemap (Linear/Reinhard/Drago), mergeMertens
Geometric	resize, rotate (NEON 1ch u8 only), pyrDown, pyrUp, buildPyramid	—
Geometric (NEON only)	resizeNV, resizeYV12, resizeYUV444, rotateNV, rotateYV12, rotateYUV444	—
Feature Detection	FAST, Harris (detect), Shi-Tomasi (detect) / shiTomasiDetect, ORB (detect + describe), SIFT, SURF, HOG, houghLines / houghLinesP, houghCircles, opticalFlowLK, descriptorMatch (bfMatch / bfMatchBinary and K-NN variants)	harrisResponse, minEigenValResponse
Transform	getPerspectiveTransform, findHomography, warpAffine, warpPerspective	getRotationMatrix2D, getAffineTransform, remap, yuvRemap
Math	—	—
Math (NEON only)	dft1d / dft2d / dftReal1d / idftReal1d / mulSpectrums	—
Drawing	—	drawLine, drawRect, drawCircle, putText
Contour Analysis	—	contourArea, arcLength, boundingRect, convexHull, approxPolyDP, minAreaRect, fitEllipse
Utilities	—	cropRect

On Android arm64-v8a, prefer the NEON variant whenever the operator exists under acl::neon::. Concrete speedups over OpenCV vary by operator and image size — see the Performance Whitepaper.