com.codename1.ui

Class Image

java.lang.Object

com.codename1.ui.Image

All Implemented Interfaces:

ActionSource

Direct Known Subclasses:

ComponentImage, DynamicImage, EncodedImage, FontImage, RGBImage, Timeline

public class Image
extends Object
implements ActionSource

Abstracts the underlying platform images allowing us to treat them as a uniform object.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Image(Object image) Subclasses may use this and point to an underlying native image which might be null for a case of an image that doesn't use native drawing

Method Summary

Modifier and Type	Method and Description
void	addActionListener(ActionListener l) Adds ActionListener to receive action events form this source.
boolean	animate()
Image	applyMask(Object mask) Applies the given alpha mask onto this image and returns the resulting image see the createMask method for indication on how to convert an image into an alpha mask.
Image	applyMask(Object mask, int x, int y) Applies the given alpha mask onto this image and returns the resulting image see the createMask method for indication on how to convert an image into an alpha mask.
Image	applyMaskAutoScale(Object mask) Applies the given alpha mask onto this image and returns the resulting image see the createMask method for indication on how to convert an image into an alpha mask.
void	asyncLock(Image internal) Async lock is the equivalent of a lock operation, however it uses the given image as the hard cache and performs the actual image loading asynchronously.
static Image	createImage(byte[] bytes, int offset, int len) creates an image from a given byte array data
static Image	createImage(InputStream stream) creates an image from an InputStream
static Image	createImage(int[] rgb, int width, int height) creates an image from an RGB image
static Image	createImage(int width, int height) Creates a white opaque mutable image that may be manipulated using getGraphics(). The sample below shows this method being used to create a screenshot for sharing the image:
static Image	createImage(int width, int height, int fillColor) Creates a mutable image that may be manipulated using getGraphics(). The sample below shows this method being used to create a screenshot for sharing the image:
static Image	createImage(Object nativeImage) Deprecated. this method is deprecated as a warning! Don't use this method unless you actually know what you are doing, if you are invoking this method without understanding the distinction between native image and Codename One image then you are using the wrong method.
static Image	createImage(String path) Creates an image from a path.
static Image	createIndexed(int width, int height, int[] palette, byte[] data) Deprecated. try to avoid using indexed images explicitly
Object	createMask() Creates a mask from the given image, a mask can be used to apply an arbitrary alpha channel to any image.
static Image	createSVG(String baseURL, boolean animated, byte[] data) Creates an SVG Image from the given byte array data and the base URL, this method will throw an exception if SVG is unsupported.
void	dispose() Deprecated. SERIOUSLY, DON'T INVOKE THIS METHOD UNLESS YOU KNOW WHAT YOU ARE DOING IT WILL CAUSE PLATFORM SPECIFC CRASHES OTHERWISE. IF YOU INVOKED THIS METHOD YOU ARE PROBABLY MAKING A MISTAKE
protected void	drawImage(Graphics g, Object nativeGraphics, int x, int y) Callback invoked internally by Codename One to draw the image/frame onto the display.
protected void	drawImage(Graphics g, Object nativeGraphics, int x, int y, int w, int h) Callback invoked internally by Codename One to draw the image/frame onto the display.
static Image	exifRotation(String capturedImage) The main use case of this method is the automatic rotation and flipping of an image returned from the camera or from the gallery, preserving the original format (jpeg or png); it detects the Exif Orientation Tag, if available (all the possible Exif Orientation Tag values are supported); transparency is not preserved.
static Image	exifRotation(String capturedImage, String rotatedImage) The main use case of this method is the automatic rotation and flipping of an image returned from the camera or from the gallery, preserving the original format (jpeg or png); it detects the Exif Orientation Tag, if available (all the possible Exif Orientation Tag values are supported); transparency is not preserved.
static Image	exifRotation(String capturedImage, String rotatedImage, int maxSize) The main use case of this method is the automatic rotation and flipping of an image returned from the camera or from the gallery, preserving the original format (jpeg or png); it detects the Exif Orientation Tag, if available (all the possible Exif Orientation Tag values are supported); transparency is not preserved.
Image	fill(int width, int height) Resizes/crops the image so that its center fills the given dimensions.
void	fireChangedEvent()
Image	flipHorizontally(boolean maintainOpacity) Flips this image on the horizontal axis
Image	flipVertically(boolean maintainOpacity) Flips this image on the vertical axis
static int	getExifOrientationTag(InputStream is) Gets the EXIF orientation tag of an image, if it's available.
static int	getExifOrientationTag(String path) Gets the EXIF orientation tag of an image, if it's available.
Graphics	getGraphics() If this is a mutable image a graphics object allowing us to draw on it is returned.
int	getHeight() Returns the height of the image
Object	getImage() Returns the platform specific image implementation, warning the implementation class can change between revisions of Codename One and platforms.
String	getImageName() The name of the image is set for some images mostly to ease the debugging of Codename One application
int[]	getRGB() Returns the content of this image as a newly created ARGB array.
void	getRGB(int[] rgbData) Returns the content of this image in the supplied ARGB array.
int[]	getRGBCached() Returns the content of this image as a newly created ARGB array or a cached instance if possible.
Object	getSVGDocument() Returns a platform specific DOM object that can be manipulated by the user to change the SVG Image
int	getWidth() Returns the width of the image
static boolean	isAlphaMutableImageSupported() Returns true if mutable images support alpha transparency
boolean	isAnimation() Returns true if this is an animated image
static boolean	isJPEG(InputStream inputStream) Very fast method to detect if the given inputStream is a JPEG image (according to its guessed mime type)
boolean	isLocked() Returns true if the image is locked
boolean	isOpaque() Indicates whether this image is opaque or not
static boolean	isPNG(InputStream inputStream) Very fast method to detect if the given inputStream is a PNG image (according to its guessed mime type)
boolean	isSVG() Indicates if this image represents an SVG file or a bitmap file
static boolean	isSVGSupported() Indicates whether the underlying platform supports creating an SVG Image
void	lock() This callback indicates that a component pointing at this image is initialized, this allows an image to make performance sensitive considerations e.g.
Image	mirror() Creates a mirror image for the given image which is useful for some RTL scenarios.
Image	modifyAlpha(byte alpha) Creates a new image instance with the alpha channel of opaque/translucent pixels within the image using the new alpha value.
Image	modifyAlpha(byte alpha, int removeColor) Creates a new image instance with the alpha channel of opaque/translucent pixels within the image using the new alpha value.
Image	modifyAlphaWithTranslucency(byte alpha) Creates a new image instance with the alpha channel of opaque pixels within the image using the new alpha value.
void	removeActionListener(ActionListener l) Removes ActionListener so that it will no longer receive events from this source.
boolean	requiresDrawImage() New label optimizations don't invoke drawImage and instead just pass the native image directly to the underlying renderer.
Image	rotate(int degrees) Returns an instance of this image rotated by the given number of degrees.
Image	rotate180Degrees(boolean maintainOpacity) Rotates the image by 180 degrees
Image	rotate270Degrees(boolean maintainOpacity) Rotates the image by 270 degrees while changing the ratio of the picture
Image	rotate90Degrees(boolean maintainOpacity) Rotates this image by 90 degrees while changing the ratio of the picture
void	scale(int width, int height) Deprecated. scale should return an image rather than modify the image in place use scaled(int, int) instead
Image	scaled(int width, int height) Returns a scaled version of this image image using the given width and height, this is a fast algorithm that preserves translucent information.
Image	scaledHeight(int height) Scales the image to the given height while updating the width based on the aspect ratio of the height
Image	scaledLargerRatio(int width, int height) Scales the image while maintaining the aspect ratio to the larger size image
Image	scaledSmallerRatio(int width, int height) Scales the image while maintaining the aspect ratio to the smaller size image
Image	scaledWidth(int width) Scales the image to the given width while updating the height based on the aspect ratio of the width
void	setImageName(String imageName) The name of the image is set for some images mostly to ease the debugging of Codename One application
Image	subImage(int x, int y, int width, int height, boolean processAlpha) Extracts a subimage from the given image allowing us to breakdown a single large image into multiple smaller images in RAM, this actually creates a standalone version of the image for use.
void	toRGB(RGBImage image, int destX, int destY, int x, int y, int width, int height) Extracts data from this image into the given RGBImage
void	unlock() This callback indicates that a component pointing at this image is now deinitilized This method may be invoked multiple times.

Methods inherited from class java.lang.Object

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

Constructor Detail

Image

protected Image(Object image)

Subclasses may use this and point to an underlying native image which might be null for a case of an image that doesn't use native drawing

Parameters:

image - native image object passed to the Codename One implementation

Method Detail

asyncLock

public void asyncLock(Image internal)

Async lock is the equivalent of a lock operation, however it uses the given image as the hard cache and performs the actual image loading asynchronously. On completion this method will invoke repaint on the main form if applicable.

Parameters:

internal - the image to show while the actual image loads.

lock

public void lock()

This callback indicates that a component pointing at this image is initialized, this allows an image to make performance sensitive considerations e.g. an encoded image might choose to cache itself in RAM. This method may be invoked multiple times.

isLocked

public boolean isLocked()

Returns true if the image is locked

Returns:

false by default

unlock

public void unlock()

This callback indicates that a component pointing at this image is now deinitilized This method may be invoked multiple times.

isSVGSupported

public static boolean isSVGSupported()

Indicates whether the underlying platform supports creating an SVG Image

Returns:

true if the method create SVG image would return a valid image object from an SVG Input stream

getSVGDocument

public Object getSVGDocument()

Returns a platform specific DOM object that can be manipulated by the user to change the SVG Image

Returns:

Platform dependent object, when JSR 226 is supported an SVGSVGElement might be returned.

createSVG

public static Image createSVG(String baseURL,
                              boolean animated,
                              byte[] data)
                       throws IOException

Creates an SVG Image from the given byte array data and the base URL, this method will throw an exception if SVG is unsupported.

Parameters:

baseURL - URL which is used to resolve relative references within the SVG file

animated - indicates if the SVG features an animation

data - the conten of the SVG file

Returns:

an image object that can be used as any other image object.

Throws:

IOException - if resource lookup fail SVG is unsupported

isSVG

public boolean isSVG()

Indicates if this image represents an SVG file or a bitmap file

Returns:

true if this is an SVG file

createMask

public Object createMask()

Creates a mask from the given image, a mask can be used to apply an arbitrary alpha channel to any image. A mask is derived from the blue channel (LSB) of the given image, other channels are ignored.
The generated mask can be used with the apply mask method.
The sample below demonstrates the masking of an image based on a circle drawn on a mutable image:

Returns:

mask object that can be used with applyMask

applyMask

public Image applyMask(Object mask,
                       int x,
                       int y)

Applies the given alpha mask onto this image and returns the resulting image see the createMask method for indication on how to convert an image into an alpha mask.

The sample below demonstrates the masking of an image based on a circle drawn on a mutable image:

Parameters:

mask - mask object created by the createMask() method.

x - starting x where to apply the mask

y - starting y where to apply the mask

Returns:

image masked based on the given object

applyMask

public Image applyMask(Object mask)

Applies the given alpha mask onto this image and returns the resulting image see the createMask method for indication on how to convert an image into an alpha mask.

Parameters:

mask - mask object created by the createMask() method.

Returns:

image masked based on the given object

Throws:

IllegalArgumentException - if the image size doesn't match the mask size

applyMaskAutoScale

public Image applyMaskAutoScale(Object mask)

Applies the given alpha mask onto this image and returns the resulting image see the createMask method for indication on how to convert an image into an alpha mask. If the image is of a different size it will be scaled to mask size.

Parameters:

mask - mask object created by the createMask() method.

Returns:

image masked based on the given object

subImage

public Image subImage(int x,
                      int y,
                      int width,
                      int height,
                      boolean processAlpha)

Extracts a subimage from the given image allowing us to breakdown a single large image into multiple smaller images in RAM, this actually creates a standalone version of the image for use.

Parameters:

x - the x offset from the image

y - the y offset from the image

width - the width of internal images

height - the height of internal images

processAlpha - whether alpha should be processed as well as part of the cutting

Returns:

An array of all the possible images that can be created from the source

mirror

public Image mirror()

Creates a mirror image for the given image which is useful for some RTL scenarios. Notice that this method isn't the most efficient way to perform this task and is designed for portability over efficiency.

Returns:

a mirrored image

rotate

public Image rotate(int degrees)

Returns an instance of this image rotated by the given number of degrees. By default 90 degree angle divisions are supported, anything else is implementation dependent. This method assumes a square image. Notice that it is inefficient in the current implementation to rotate to non-square angles,

E.g. rotating an image to 45, 90 and 135 degrees is inefficient. Use rotatate to 45, 90 and then rotate the 45 to another 90 degrees to achieve the same effect with less memory.

Parameters:

degrees - A degree in right angle must be larger than 0 and up to 359 degrees

Returns:

new image instance with the closest possible rotation

createIndexed

public static Image createIndexed(int width,
                                  int height,
                                  int[] palette,
                                  byte[] data)

Deprecated. try to avoid using indexed images explicitly

Creates an indexed image with byte data this method may return a native indexed image rather than an instance of the IndexedImage class

Parameters:

width - image width

height - image height

palette - the color palette to use with the byte data

data - byte data containing palette offsets to map to ARGB colors

modifyAlpha

public Image modifyAlpha(byte alpha)

Creates a new image instance with the alpha channel of opaque/translucent pixels within the image using the new alpha value. Transparent (alpha == 0) pixels remain transparent. All other pixels will have the new alpha value.

Parameters:

alpha - New value for the entire alpha channel

Returns:

Translucent/Opaque image based on the alpha value and the pixels of this image

modifyAlphaWithTranslucency

public Image modifyAlphaWithTranslucency(byte alpha)

Creates a new image instance with the alpha channel of opaque pixels within the image using the new alpha value. Transparent (alpha == 0) pixels remain transparent. Semi translucent pixels will be multiplied by the ratio difference and their translucency reduced appropriately.

Parameters:

alpha - New value for the entire alpha channel

Returns:

Translucent/Opaque image based on the alpha value and the pixels of this image

modifyAlpha

public Image modifyAlpha(byte alpha,
                         int removeColor)

Creates a new image instance with the alpha channel of opaque/translucent pixels within the image using the new alpha value. Transparent (alpha == 0) pixels remain transparent. All other pixels will have the new alpha value.

Parameters:

alpha - New value for the entire alpha channel

removeColor - pixels matching this color are made transparent (alpha channel ignored)

Returns:

Translucent/Opaque image based on the alpha value and the pixels of this image

createImage

public static Image createImage(String path)
                         throws IOException

Creates an image from a path.

Parameters:

path - If path begins with file: then the image will be loaded from FileSystemStorage. Otherwise it will load from the jar resources.

Returns:

newly created image object

Throws:

IOException

createImage

public static Image createImage(Object nativeImage)

Deprecated. this method is deprecated as a warning! Don't use this method unless you actually know what you are doing, if you are invoking this method without understanding the distinction between native image and Codename One image then you are using the wrong method.

creates an image from the given native image (e.g. MIDP image object)

Parameters:

nativeImage -

Returns:

newly created Codename One image object

createImage

public static Image createImage(InputStream stream)
                         throws IOException

creates an image from an InputStream

Parameters:

stream - a given InputStream

Returns:

the newly created image

Throws:

IOException

createImage

public static Image createImage(int[] rgb,
                                int width,
                                int height)

creates an image from an RGB image

Parameters:

rgb - the RGB image array data

width - the image width

height - the image height

Returns:

an image from an RGB image

createImage

public static Image createImage(int width,
                                int height)

Creates a white opaque mutable image that may be manipulated using getGraphics().
The sample below shows this method being used to create a screenshot for sharing the image:

The sample below demonstrates the drawing of a mask image to create a round image effect

Parameters:

width - the image width

height - the image height

Returns:

an image in a given width and height dimension

isAlphaMutableImageSupported

public static boolean isAlphaMutableImageSupported()

Returns true if mutable images support alpha transparency

Returns:

true if mutable images support alpha in their fillColor argument

createImage

public static Image createImage(int width,
                                int height,
                                int fillColor)

Creates a mutable image that may be manipulated using getGraphics().
The sample below shows this method being used to create a screenshot for sharing the image:

Parameters:

width - the image width

height - the image height

fillColor - the color with which the image should be initially filled

Returns:

an image in a given width and height dimension

createImage

public static Image createImage(byte[] bytes,
                                int offset,
                                int len)

creates an image from a given byte array data

Parameters:

bytes - the array of image data in a supported image format

offset - the offset of the start of the data in the array

len - the length of the data in the array

Returns:

the newly created image

getGraphics

public Graphics getGraphics()

If this is a mutable image a graphics object allowing us to draw on it is returned.

Returns:

Graphics object allowing us to manipulate the content of a mutable image

getWidth

public int getWidth()

Returns the width of the image

Returns:

the width of the image

getHeight

public int getHeight()

Returns the height of the image

Returns:

the height of the image

drawImage

protected void drawImage(Graphics g,
                         Object nativeGraphics,
                         int x,
                         int y)

Callback invoked internally by Codename One to draw the image/frame onto the display. Image subclasses can override this method to perform drawing of custom image types.

Parameters:

g - the graphics object

nativeGraphics - the underlying native graphics which might be essential for some image types

x - the x coordinate

y - the y coordinate

drawImage

protected void drawImage(Graphics g,
                         Object nativeGraphics,
                         int x,
                         int y,
                         int w,
                         int h)

Callback invoked internally by Codename One to draw the image/frame onto the display. Image subclasses can override this method to perform drawing of custom image types.

Parameters:

g - the graphics object

nativeGraphics - the underlying native graphics which might be essential for some image types

x - the x coordinate

y - the y coordinate

w - the width to occupy

h - the height to occupy

toRGB

public void toRGB(RGBImage image,
                  int destX,
                  int destY,
                  int x,
                  int y,
                  int width,
                  int height)

Extracts data from this image into the given RGBImage

Parameters:

image - RGBImage that would receive pixel data

destX - x location within RGBImage into which the data will be written

destY - y location within RGBImage into which the data will be written

x - location within the source image

y - location within the source image

width - size of the image to extract from the source image

height - size of the image to extract from the source image

getRGB

public int[] getRGB()

Returns the content of this image as a newly created ARGB array.

Returns:

new array instance containing the ARGB data within this image

getRGB

public void getRGB(int[] rgbData)

Returns the content of this image in the supplied ARGB array.

Parameters:

rgbData -

getRGBCached

public int[] getRGBCached()

Returns the content of this image as a newly created ARGB array or a cached instance if possible. Note that cached instances may be garbage collected.

Returns:

array instance containing the ARGB data within this image

scaledWidth

public Image scaledWidth(int width)

Scales the image to the given width while updating the height based on the aspect ratio of the width

Parameters:

width - the given new image width

Returns:

the newly created image

scaledHeight

public Image scaledHeight(int height)

Scales the image to the given height while updating the width based on the aspect ratio of the height

Parameters:

height - the given new image height

Returns:

the newly created image

scaledSmallerRatio

public Image scaledSmallerRatio(int width,
                                int height)

Scales the image while maintaining the aspect ratio to the smaller size image

Parameters:

width - the given new image width

height - the given new image height

Returns:

the newly created image

scaledLargerRatio

public Image scaledLargerRatio(int width,
                               int height)

Scales the image while maintaining the aspect ratio to the larger size image

Parameters:

width - the given new image width

height - the given new image height

Returns:

the newly created image

scaled

public Image scaled(int width,
                    int height)

Returns a scaled version of this image image using the given width and height, this is a fast algorithm that preserves translucent information. The method accepts -1 to preserve aspect ratio in the given axis.

Parameters:

width - width for the scaling

height - height of the scaled image

Returns:

new image instance scaled to the given height and width

fill

public Image fill(int width,
                  int height)

Resizes/crops the image so that its center fills the given dimensions. This is similar to Style.BACKGROUND_IMAGE_SCALED_FILL

Parameters:

width - the width to fill

height - the height to fill

Returns:

a new image (or the same image if dimensions happen to match) filling the width/height

getImage

public Object getImage()

Returns the platform specific image implementation, warning the implementation class can change between revisions of Codename One and platforms.

Returns:

platform specific native implementation for this image object

scale

public void scale(int width,
                  int height)

Deprecated. scale should return an image rather than modify the image in place use scaled(int, int) instead

Scale the image to the given width and height, this is a fast algorithm that preserves translucent information

Parameters:

width - width for the scaling

height - height of the scaled image

isAnimation

public boolean isAnimation()

Returns true if this is an animated image

Returns:

true if this image represents an animation

animate

public boolean animate()

isOpaque

public boolean isOpaque()

Indicates whether this image is opaque or not

Returns:

true if the image is completely opqaque which allows for some heavy optimizations

getImageName

public String getImageName()

The name of the image is set for some images mostly to ease the debugging of Codename One application

Returns:

the imageName

setImageName

public void setImageName(String imageName)

The name of the image is set for some images mostly to ease the debugging of Codename One application

Parameters:

imageName - the imageName to set

dispose

public void dispose()

Deprecated. SERIOUSLY, DON'T INVOKE THIS METHOD UNLESS YOU KNOW WHAT YOU ARE DOING IT WILL CAUSE PLATFORM SPECIFC CRASHES OTHERWISE. IF YOU INVOKED THIS METHOD YOU ARE PROBABLY MAKING A MISTAKE

DO NOT CALL THIS METHOD UNLESS YOU KNOW WHAT YOU ARE DOING, IT WILL CAUSE PLATFORM SPECIFC CRASHES OTHERWISE! Images dispose automatically for most cases except for very rare special cases. Images on devices usually holds a native memory, some platforms garbage collectors might fail to release the native and to fail with out of memory errors. Use this method to make sure the image will be released from memory, after calling this the image will become unusable.

rotate90Degrees

public Image rotate90Degrees(boolean maintainOpacity)

Rotates this image by 90 degrees while changing the ratio of the picture

Parameters:

maintainOpacity - whether the opacity in the image should be maintained

Returns:

a new image rotated by 90 degrees

rotate180Degrees

public Image rotate180Degrees(boolean maintainOpacity)

Rotates the image by 180 degrees

Parameters:

maintainOpacity - whether the opacity in the image should be maintained

Returns:

a new image rotated by 180 degrees

rotate270Degrees

public Image rotate270Degrees(boolean maintainOpacity)

Rotates the image by 270 degrees while changing the ratio of the picture

Parameters:

maintainOpacity - whether the opacity in the image should be maintained

Returns:

a new image rotated by 270 degrees

flipHorizontally

public Image flipHorizontally(boolean maintainOpacity)

Flips this image on the horizontal axis

Parameters:

maintainOpacity - whether the opacity in the image should be maintained

Returns:

a new image flipped

flipVertically

public Image flipVertically(boolean maintainOpacity)

Flips this image on the vertical axis

Parameters:

maintainOpacity - whether the opacity in the image should be maintained

Returns:

a new image flipped

requiresDrawImage

public boolean requiresDrawImage()

New label optimizations don't invoke drawImage and instead just pass the native image directly to the underlying renderer. This is problematic for some image types specifically timeline & FontImage and this method allows these classes to indicate that they need that legacy behavior of calling drawImage.

Returns:

true if a drawImage call is a required

addActionListener

public void addActionListener(ActionListener l)

Description copied from interface: ActionSource

Adds ActionListener to receive action events form this source.

Specified by:

addActionListener in interface ActionSource

removeActionListener

public void removeActionListener(ActionListener l)

Description copied from interface: ActionSource

Removes ActionListener so that it will no longer receive events from this source.

Specified by:

removeActionListener in interface ActionSource

fireChangedEvent

public void fireChangedEvent()

exifRotation

public static Image exifRotation(String capturedImage)
                          throws IOException

The main use case of this method is the automatic rotation and flipping of an image returned from the camera or from the gallery, preserving the original format (jpeg or png); it detects the Exif Orientation Tag, if available (all the possible Exif Orientation Tag values are supported); transparency is not preserved.

If there is no rotation or flipping, the image is only copied or scaled if necessary; if the capturedImage has a format different from jpeg and png, it is copied as it is.
Note that this method doesn't rely on the file extension, but on the mime type of the capturedImage, since some devices don't give appropriate extension to images returned from the gallery.

You can test all the possible orientation values downloading the images from the repository EXIF Orientation-flag example images

Code example:

Parameters:

capturedImage - is the FileSystemStorage path of a captured photo, usually inside a temporary directory

Returns:

the rotated and/or flipped image

Throws:

IOException

exifRotation

public static Image exifRotation(String capturedImage,
                                 String rotatedImage)
                          throws IOException

The main use case of this method is the automatic rotation and flipping of an image returned from the camera or from the gallery, preserving the original format (jpeg or png); it detects the Exif Orientation Tag, if available (all the possible Exif Orientation Tag values are supported); transparency is not preserved.

If there is no rotation or flipping, the image is only copied or scaled if necessary; if the capturedImage has a format different from jpeg and png, it is copied as it is.
Note that this method doesn't rely on the file extension, but on the mime type of the capturedImage, since some devices don't give appropriate extension to images returned from the gallery.

You can test all the possible orientation values downloading the images from the repository EXIF Orientation-flag example images

Code example:

Parameters:

capturedImage - is the FileSystemStorage path of a captured photo, usually inside a temporary directory

rotatedImage - is the FileSystemStorage path in which the rotated photo is stored, normally this should be inside the FileSystemStorage.getAppHomePath(); it can be null if you don't want to save the rotated image to the FileSystemStorage.

Returns:

the rotated and/or flipped image

Throws:

IOException

exifRotation

public static Image exifRotation(String capturedImage,
                                 String rotatedImage,
                                 int maxSize)
                          throws IOException

The main use case of this method is the automatic rotation and flipping of an image returned from the camera or from the gallery, preserving the original format (jpeg or png); it detects the Exif Orientation Tag, if available (all the possible Exif Orientation Tag values are supported); transparency is not preserved.

However, rotating and/or flipping an hi-res image is very inefficient, that's why you should consider to pass a maxSize value as small as possible: it makes this method working faster.

If there is no rotation or flipping, the image is only copied or scaled if necessary; if the capturedImage has a format different from jpeg and png, it is copied as it is.
Note that this method doesn't rely on the file extension, but on the mime type of the capturedImage, since some devices don't give appropriate extension to images returned from the gallery.

You can test all the possible orientation values downloading the images from the repository EXIF Orientation-flag example images

Code example:

Parameters:

capturedImage - is the FileSystemStorage path of a captured photo, usually inside a temporary directory

rotatedImage - is the FileSystemStorage path in which the rotated photo is stored, normally this should be inside the FileSystemStorage.getAppHomePath(); it can be null if you don't want to save the rotated image to the FileSystemStorage.

maxSize - is the maximum value of the width and height of the rotated images, that is scaled if necessary, keeping the ratio.

Returns:

the com.codename1.ui.Image

Throws:

IOException

getExifOrientationTag

public static int getExifOrientationTag(String path)
                                 throws IOException

Gets the EXIF orientation tag of an image, if it's available.

The Exif Orientation Tag is a number from 0 to 8, for the explanation of each value see the Exif Orientation Tag page

You can test all the possible orientation values downloading the images from the repository EXIF Orientation-flag example images

Parameters:

path - FileSystemStorage path

Returns:

a value from 0 to 8; 0 is default in case of error or unavailable EXIF data.

Throws:

IOException

getExifOrientationTag

public static int getExifOrientationTag(InputStream is)

Gets the EXIF orientation tag of an image, if it's available.

The Exif Orientation Tag is a number from 0 to 8, for the explanation of each value see the Exif Orientation Tag page

You can test all the possible orientation values downloading the images from the repository EXIF Orientation-flag example images

Parameters:

is -

Returns:

a value from 0 to 8; 0 is default in case of error or unavailable EXIF data.

isJPEG

public static boolean isJPEG(InputStream inputStream)
                      throws IOException

Very fast method to detect if the given inputStream is a JPEG image (according to its guessed mime type)

Parameters:

inputStream -

Returns:

true if jpeg, false otherwise

Throws:

IOException

isPNG

public static boolean isPNG(InputStream inputStream)
                     throws IOException

Very fast method to detect if the given inputStream is a PNG image (according to its guessed mime type)

Parameters:

inputStream -

Returns:

true if PNG, false otherwise

Throws:

IOException