com.foreach.imageserver.math

Class ImageServerConversionUtils

java.lang.Object

com.foreach.imageserver.math.ImageServerConversionUtils

public class ImageServerConversionUtils
extends Object

Utility methods to calculate/translate DTO instances.

Author:

Arne Vandamme

Method Summary

Modifier and Type	Method and Description
static AspectRatio	calculateAspectRatio(DimensionsDto dimensions)
static AspectRatio	calculateAspectRatio(ImageResolutionDto resolutionDto)
static int	calculateDistance(@NonNull DimensionsDto from, @NonNull DimensionsDto to) Calculates the distance between two dimensions.
static int	calculateDistance(ImageResolutionDto from, ImageResolutionDto to)
static CropDto	extendCrop(CropDto original, AspectRatio aspectRatio) This will extend an existing crop to match a given aspect ratio.
static boolean	fitsIn(DimensionsDto original, DimensionsDto boundaries) Checks if the area represented by dimensions fits inside the area defined by the box (the original area should be the same surface or smaller).
static boolean	isWithinBox(CropDto crop, DimensionsDto box) Checks if a crop is entirely positioned within a box.
static CropDto	moveToFit(CropDto original, DimensionsDto box) Will shift a crop to fit entirely inside the box.
static CropDto	normalize(CropDto original, DimensionsDto box) Will translate a crop to fit inside the box specified.
static DimensionsDto	normalize(DimensionsDto original, AspectRatio aspectRatio) Will verify and modify the dimensions so that they match the aspect ratio.
static DimensionsDto	normalize(DimensionsDto original, DimensionsDto boundaries) Will calculate the unknown dimensions for the original according to the boundaries specified.
static DimensionsDto	scaleToFitIn(DimensionsDto original, DimensionsDto box) Will downscale the dimensions to fit in the boundaries if they are larger.
static CropDto	shrinkCrop(CropDto original, AspectRatio aspectRatio) This will shrink an existing crop to match a given aspect ratio.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

calculateAspectRatio

public static AspectRatio calculateAspectRatio(ImageResolutionDto resolutionDto)

calculateAspectRatio

public static AspectRatio calculateAspectRatio(DimensionsDto dimensions)

extendCrop

public static CropDto extendCrop(CropDto original,
                                 AspectRatio aspectRatio)

This will extend an existing crop to match a given aspect ratio. The center point of the crop will be kept, so extending will happen equally on all sides involved. This can return a crop with negative x and y coordinates. Use moveToFit(CropDto, DimensionsDto) if you also want the crop to be moved about to fit it in the visible coordinates box.

Crop parameters like source and box will be kept.

Parameters:

original - crop coordinates

aspectRatio - the crop should match

Returns:

modified crop

See Also:

moveToFit(CropDto, DimensionsDto)

shrinkCrop

public static CropDto shrinkCrop(CropDto original,
                                 AspectRatio aspectRatio)

This will shrink an existing crop to match a given aspect ratio. The center point of the crop will be kept. Assuming that the original crop had valid coordinates, this will result in a valid crop.

Crop parameters like source and box will be kept.

Parameters:

original - crop coordinates

aspectRatio - the crop should match

Returns:

modified crop

moveToFit

public static CropDto moveToFit(CropDto original,
                                DimensionsDto box)

Will shift a crop to fit entirely inside the box. Usually used after extendCrop(CropDto, AspectRatio) to verify that the resulting extension does not surpass the box boundaries. This counters the center point based extending of a crop.

This function will throw an exception if it is not possible to fit the crop inside the box.

Parameters:

original - crop coordinates

box - the crop should fit in

Returns:

modified crop

Throws:

IllegalArgumentException - if the crop dimensions are impossible to fit in the box

normalize

public static DimensionsDto normalize(DimensionsDto original,
                                      DimensionsDto boundaries)

Will calculate the unknown dimensions for the original according to the boundaries specified. Any unknown dimensions will be scaled according to the aspect ratio of the boundaries.

Parameters:

original - dimensions

boundaries - for the new dimensions

Returns:

normalized dimensions

normalize

public static DimensionsDto normalize(DimensionsDto original,
                                      AspectRatio aspectRatio)

Will verify and modify the dimensions so that they match the aspect ratio. The resulting dimensions will never be smaller than the original one and always one of the original dimensions will be kept.

Parameters:

original - dimensions

aspectRatio - to use when normalizing the dimensions

Returns:

normalized dimensions

normalize

public static CropDto normalize(CropDto original,
                                DimensionsDto box)

Will translate a crop to fit inside the box specified. This requires the source dimensions of the crop to be set.

Parameters:

original - crop

box - to use for translating the crop coordinates

Returns:

normalized crop

scaleToFitIn

public static DimensionsDto scaleToFitIn(DimensionsDto original,
                                         DimensionsDto box)

Will downscale the dimensions to fit in the boundaries if they are larger.

Parameters:

original - dimensions

box - that the translated dimensions should fit in

Returns:

translated dimensions

fitsIn

public static boolean fitsIn(DimensionsDto original,
                             DimensionsDto boundaries)

Checks if the area represented by dimensions fits inside the area defined by the box (the original area should be the same surface or smaller).

Parameters:

original - dimensions to check

boundaries - that the dimensions should fit in

Returns:

true if dimensions fit

isWithinBox

public static boolean isWithinBox(CropDto crop,
                                  DimensionsDto box)

Checks if a crop is entirely positioned within a box. The crop dimensions should be smaller or equal to the box dimensions, and the left top coordinates should not be negative.

Parameters:

crop - to check

box - that should contain the crop

Returns:

true if crop fits

calculateDistance

public static int calculateDistance(ImageResolutionDto from,
                                    ImageResolutionDto to)

calculateDistance

public static int calculateDistance(@NonNull
                                    @NonNull DimensionsDto from,
                                    @NonNull
                                    @NonNull DimensionsDto to)

Calculates the distance between two dimensions. If the dimensions are exactly the same, the distance is 0. If the first dimensions fits entirely in the second, the distance will be positive. The larger the second dimension, the greater the distance number. If the first dimension is larger than the second dimension, the distance number will be negative. Distances closer to 0 indicate how much smaller the scond dimension is.

A dimension is considered smaller as soon as a single side is smaller. Calculating the distance is impossible if any of the arguments have an unknown dimension.

The actual distance number is the delta between the two surfaces. If the surface is the same (but dimensions are reversed), then the distance will be -1.

Parameters:

from - dimension

to - dimension

Returns:

distance number