jdk.awt.image.RescaleOp — clojure-interop/java.awt 1.0.5

This class performs a pixel-by-pixel rescaling of the data in the source image by multiplying the sample values for each pixel by a scale factor and then adding an offset. The scaled sample values are clipped to the minimum/maximum representable in the destination image.

The pseudo code for the rescaling operation is as follows:

for each pixel from Source object { for each band/component of the pixel { dstElement = (srcElement*scaleFactor) offset } }

For Rasters, rescaling operates on bands. The number of sets of scaling constants may be one, in which case the same constants are applied to all bands, or it must equal the number of Source Raster bands.

For BufferedImages, rescaling operates on color and alpha components. The number of sets of scaling constants may be one, in which case the same constants are applied to all color (but not alpha) components. Otherwise, the number of sets of scaling constants may equal the number of Source color components, in which case no rescaling of the alpha component (if present) is performed. If neither of these cases apply, the number of sets of scaling constants must equal the number of Source color components plus alpha components, in which case all color and alpha components are rescaled.

BufferedImage sources with premultiplied alpha data are treated in the same manner as non-premultiplied images for purposes of rescaling. That is, the rescaling is done per band on the raw data of the BufferedImage source without regard to whether the data is premultiplied. If a color conversion is required to the destination ColorModel, the premultiplied state of both source and destination will be taken into account for this step.

Images with an IndexColorModel cannot be rescaled.

If a RenderingHints object is specified in the constructor, the color rendering hint and the dithering hint may be used when color conversion is required.

Note that in-place operation is allowed (i.e. the source and destination can be the same object).

->rescale-op clj

(->rescale-op scale-factors offsets hints)

Constructor.

Constructs a new RescaleOp with the desired scale factors and offsets. The length of the scaleFactor and offset arrays must meet the restrictions stated in the class comments above. The RenderingHints argument may be null.

scale-factors - the specified scale factors - float[] offsets - the specified offsets - float[] hints - the specified RenderingHints, or null - java.awt.RenderingHints

create-compatible-dest-image clj

(create-compatible-dest-image this src dest-cm)

Creates a zeroed destination image with the correct size and number of bands.

src - Source image for the filter operation. - java.awt.image.BufferedImage dest-cm - ColorModel of the destination. If null, the ColorModel of the source will be used. - java.awt.image.ColorModel

returns: the zeroed-destination image. - java.awt.image.BufferedImage

create-compatible-dest-raster clj

(create-compatible-dest-raster this src)

Creates a zeroed-destination Raster with the correct size and number of bands, given this source.

src - the source Raster - java.awt.image.Raster

returns: the zeroed-destination Raster. - java.awt.image.WritableRaster

filter clj

(filter this src dst)

Rescales the source BufferedImage. If the color model in the source image is not the same as that in the destination image, the pixels will be converted in the destination. If the destination image is null, a BufferedImage will be created with the source ColorModel. An IllegalArgumentException may be thrown if the number of scaling factors/offsets in this object does not meet the restrictions stated in the class comments above, or if the source image has an IndexColorModel.

src - the BufferedImage to be filtered - java.awt.image.BufferedImage dst - the destination for the filtering operation or null - java.awt.image.BufferedImage

returns: the filtered BufferedImage. - java.awt.image.BufferedImage

throws: java.lang.IllegalArgumentException - if the ColorModel of src is an IndexColorModel, or if the number of scaling factors and offsets in this RescaleOp do not meet the requirements stated in the class comments.

get-bounds-2-d clj

(get-bounds-2-d this src)

Returns the bounding box of the rescaled destination image. Since this is not a geometric operation, the bounding box does not change.

src - The BufferedImage to be filtered - java.awt.image.BufferedImage

returns: The Rectangle2D representing the destination image's bounding box. - java.awt.geom.Rectangle2D

get-num-factors clj

(get-num-factors this)

Returns the number of scaling factors and offsets used in this RescaleOp.

returns: the number of scaling factors and offsets of this RescaleOp. - int

get-offsets clj

(get-offsets this offsets)

Returns the offsets in the given array. The array is also returned for convenience. If offsets is null, a new array will be allocated.

offsets - the array to contain the offsets of this RescaleOp - float[]

returns: the offsets of this RescaleOp. - float[]

get-point-2-d clj

(get-point-2-d this src-pt dst-pt)

Returns the location of the destination point given a point in the source. If dstPt is non-null, it will be used to hold the return value. Since this is not a geometric operation, the srcPt will equal the dstPt.

src-pt - a point in the source image - java.awt.geom.Point2D dst-pt - the destination point or null - java.awt.geom.Point2D

returns: the location of the destination point. - java.awt.geom.Point2D

get-rendering-hints clj

(get-rendering-hints this)

Returns the rendering hints for this op.

returns: the rendering hints of this RescaleOp. - java.awt.RenderingHints

get-scale-factors clj

(get-scale-factors this scale-factors)

Returns the scale factors in the given array. The array is also returned for convenience. If scaleFactors is null, a new array will be allocated.

scale-factors - the array to contain the scale factors of this RescaleOp - float[]

returns: the scale factors of this RescaleOp. - float[]