op warpAffine
FireSight wrapper for OpenCV warpAffine:
-
angle Rotate image counter-clockwise by given angle in degrees. Default
0 - cx Center of rotation. Default is center of image
- cy Center of rotation. Default is center of image
-
dx Translation after rotation. Default is
0 -
dy Translation after rotation. Default is
0 -
width Width of output image. Default is width of original image. FireSight: If
-1, width will be automatically computed to show full image (vs. cropping it). -
height Height of output image. Default is height of original image. FireSight: If
-1, height will be automatically computed to show full image (vs. cropping it). -
scale Size scale of output image. Default is
1 -
reflect JSON array [x,y] of reflection vector. Default is
[0,0]. Only x-, y- and xy-axis reflections are supported because of a bug in OpenCV. -
borderValue Color to use for background. Default is
[0,0,0]BGR -
borderMode Specifies how border of transformed image should be filled:
BORDER_CONSTANTfills with borderValue;BORDER_REPLICATEreplicates border pixels;BORDER_REFLECTfills with a mirror image of source image doubling the border value;BORDER_REFLECT_101fills with a mirror image of source image without doubling the border value;BORDER_WRAPfills with repeated copies of the source image.
{}
Example: Rotate a duck by 30 degrees and scale it by 0.5 pipeline
firesight -i img/duck.jpg -p json/warpAffine-rotate.json -o target/warpAffine-rotate.jpg
Example: Rotate a duck by 30 degrees with BORDER_REPLICATE pipeline
firesight -i img/duck.jpg -p json/warpAffine-rotate2.json -o target/warpAffine-rotate2.jpg
The choice of border fill when rotating an image can strongly influence the use of that image as a template for matching. Using BORDER_REPLICATE can greatly improve matching accuracy. Notice that rotation destroys image information and replaces it with replicated borders:
Example: Translate a duck by (50,50) pixels pipeline
firesight -i img/duck.jpg -p json/warpAffine-translate.json -o target/warpAffine-translate.jpg
Example: Flip a duck pipeline
firesight -i img/duck.png -p json/fliph.json -o target/fliph.png
