com.google.appengine.api.images
Class ImagesServiceFactory

java.lang.Object
  com.google.appengine.api.images.ImagesServiceFactory

public final class ImagesServiceFactory
extends java.lang.Object

Factory for creating an ImagesService, Images and Transforms.

Method Summary

static ImagesService	getImagesService() Creates an implementation of the ImagesService.
static Composite	makeComposite(Image image, int xOffset, int yOffset, float opacity, Composite.Anchor anchor) Creates an image composition operation.
static CompositeTransform	makeCompositeTransform() Creates a composite transform that can represent multiple transforms applied in series.
static CompositeTransform	makeCompositeTransform(java.util.Collection<Transform> transforms) Creates a composite transform that can represent multiple transforms applied in series.
static Transform	makeCrop(double leftX, double topY, double rightX, double bottomY) Creates a transform that will crop an image to fit within the bounding box specified.
static Transform	makeCrop(float leftX, float topY, float rightX, float bottomY) Creates a transform that will crop an image to fit within the bounding box specified.
static Transform	makeHorizontalFlip() Creates a transform that will horizontally flip an image.
static Image	makeImage(byte[] imageData) Creates an image from the provided imageData.
static Image	makeImageFromBlob(BlobKey blobKey) Create an image backed by the specified blobKey.
static Transform	makeImFeelingLucky() Creates a transform that automatically adjust contrast and color levels.
static Transform	makeResize(int width, int height) Creates a transform that will resize an image to fit within a box with width width and height height.
static Transform	makeResize(int width, int height, boolean allowStretch) Creates a resize transform that will resize an image to fit within a box of width width and height height.
static Transform	makeResize(int width, int height, double cropOffsetX, double cropOffsetY) Creates a transform that will resize an image to exactly fit a box with width width and height height by resizing to the less constraining dimension and cropping the other.
static Transform	makeResize(int width, int height, float cropOffsetX, float cropOffsetY) Creates a transform that will resize an image to exactly fit a box with width width and height height by resizing to the less constraining dimension and cropping the other.
static Transform	makeRotate(int degrees) Creates a transform that rotates an image by degrees degrees clockwise.
static Transform	makeVerticalFlip() Creates a transform that will vertically flip an image.

Methods inherited from class java.lang.Object

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

Method Detail

getImagesService

public static ImagesService getImagesService()

Creates an implementation of the ImagesService.

Returns:

an images service

makeImage

public static Image makeImage(byte[] imageData)

Creates an image from the provided imageData.

Parameters:

imageData - image data to store in the image

Returns:

an Image containing the supplied image data

Throws:

java.lang.IllegalArgumentException - If imageData is null or empty.

makeImageFromBlob

public static Image makeImageFromBlob(BlobKey blobKey)

Create an image backed by the specified blobKey. Note that the returned Image object can be used with all ImagesService methods, but most of the methods on the Image itself will currently throw UnsupportedOperationException.

Parameters:

blobKey - referencing the image

Returns:

an Image that references the specified blob data

makeResize

public static Transform makeResize(int width,
                                   int height)

Creates a transform that will resize an image to fit within a box with width width and height height.

Parameters:

width - width of the bounding box

height - height of the bounding box

Returns:

a resize transform

Throws:

java.lang.IllegalArgumentException - If width or height are negative or greater than MAX_RESIZE_DIMENSIONS or if both width and height are 0.

makeResize

public static Transform makeResize(int width,
                                   int height,
                                   boolean allowStretch)

Creates a resize transform that will resize an image to fit within a box of width width and height height. If allowStretch is true, the aspect ratio of the original image will be ignored.

Parameters:

width - width of the bounding box

height - height of the bounding box

allowStretch - allow the image to be resized ignoring the aspect ratio

Returns:

a resize transform

Throws:

java.lang.IllegalArgumentException - If width or height are negative or greater than MAX_RESIZE_DIMENSIONS, if both width and height are 0 or if is True and either width or height are 0.

makeResize

public static Transform makeResize(int width,
                                   int height,
                                   float cropOffsetX,
                                   float cropOffsetY)

Creates a transform that will resize an image to exactly fit a box with width width and height height by resizing to the less constraining dimension and cropping the other. The center of the crop region is controlled by cropOffsetX and cropOffsetY.

Parameters:

width - width of the bounding box

height - height of the bounding box

cropOffsetX - the relative horizontal position of the center

cropOffsetY - the relative vertical position of the center

Returns:

a resize transform

Throws:

java.lang.IllegalArgumentException - If width or height are negative or greater than MAX_RESIZE_DIMENSIONS, if either of width and height are 0 or if cropOffsetX or cropOffsetY are outside the range 0.0 to 1.0.

makeResize

public static Transform makeResize(int width,
                                   int height,
                                   double cropOffsetX,
                                   double cropOffsetY)

Creates a transform that will resize an image to exactly fit a box with width width and height height by resizing to the less constraining dimension and cropping the other. The center of the crop region is controlled by cropOffsetX and cropOffsetY.

Parameters:

width - width of the bounding box

height - height of the bounding box

cropOffsetX - the relative horizontal position of the center

cropOffsetY - the relative vertical position of the center

Returns:

a resize transform

Throws:

java.lang.IllegalArgumentException - If width or height are negative or greater than MAX_RESIZE_DIMENSIONS, if either of width and height are 0 or if cropOffsetX or cropOffsetY are outside the range 0.0 to 1.0.

makeCrop

public static Transform makeCrop(float leftX,
                                 float topY,
                                 float rightX,
                                 float bottomY)

Creates a transform that will crop an image to fit within the bounding box specified. The arguments define the top left and bottom right corners of the bounding box used to crop the image as a percentage of the total image size. Each argument should be in the range 0.0 to 1.0 inclusive.

Parameters:

leftX - X coordinate of the top left corner of the bounding box

topY - Y coordinate of the top left corner of the bounding box

rightX - X coordinate of the bottom right corner of the bounding box

bottomY - Y coordinate of the bottom right corner of the bounding box

Returns:

a crop transform

Throws:

java.lang.IllegalArgumentException - If any of the arguments are outside the range 0.0 to 1.0 or if leftX >= rightX or topY >= bottomY.

makeCrop

public static Transform makeCrop(double leftX,
                                 double topY,
                                 double rightX,
                                 double bottomY)

Creates a transform that will crop an image to fit within the bounding box specified. The arguments define the top left and bottom right corners of the bounding box used to crop the image as a percentage of the total image size. Each argument should be in the range 0.0 to 1.0 inclusive.

Parameters:

leftX - X coordinate of the top left corner of the bounding box

topY - Y coordinate of the top left corner of the bounding box

rightX - X coordinate of the bottom right corner of the bounding box

bottomY - Y coordinate of the bottom right corner of the bounding box

Returns:

a crop transform

Throws:

java.lang.IllegalArgumentException - If any of the arguments are outside the range 0.0 to 1.0 or if leftX >= rightX or topY >= bottomY.

makeVerticalFlip

public static Transform makeVerticalFlip()

Creates a transform that will vertically flip an image.

Returns:

a vertical flip transform

makeHorizontalFlip

public static Transform makeHorizontalFlip()

Creates a transform that will horizontally flip an image.

Returns:

a horizontal flip transform

makeRotate

public static Transform makeRotate(int degrees)

Creates a transform that rotates an image by degrees degrees clockwise.

Parameters:

degrees - The number of degrees by which to rotate. Must be a multiple of 90.

Returns:

a rotation transform

Throws:

java.lang.IllegalArgumentException - If degrees is not divisible by 90

makeImFeelingLucky

public static Transform makeImFeelingLucky()

Creates a transform that automatically adjust contrast and color levels. This is similar to the "I'm Feeling Lucky" button in Picasa.

Returns:

an ImFeelingLucky autolevel transform

makeCompositeTransform

public static CompositeTransform makeCompositeTransform(java.util.Collection<Transform> transforms)

Creates a composite transform that can represent multiple transforms applied in series.

Parameters:

transforms - Transforms for this composite transform to apply.

Returns:

a composite transform containing the provided transforms

makeCompositeTransform

public static CompositeTransform makeCompositeTransform()

Creates a composite transform that can represent multiple transforms applied in series.

Returns:

an empty composite transform

makeComposite

public static Composite makeComposite(Image image,
                                      int xOffset,
                                      int yOffset,
                                      float opacity,
                                      Composite.Anchor anchor)

Creates an image composition operation.

Parameters:

image - The image to be composited.

xOffset - Offset in the x axis from the anchor point.

yOffset - Offset in the y axis from the anchor point.

opacity - Opacity to be used for the image in range [0.0, 1.0].

anchor - Anchor position from the enum Composite.Anchor. The anchor position of the image is aligned with the anchor position of the canvas and then the offsets are applied.

Returns:

A composition operation.

Throws:

java.lang.IllegalArgumentException - If image is null or empty, xOffset or yOffset is outside the range [-4000, 4000], opacity is outside the range [0.0, 1.0] or anchor is null.