Package adams.data.image

Class BufferedImageHelper

java.lang.Object

adams.data.image.BufferedImageHelper

public class BufferedImageHelper
extends Object

Helper class for BufferedImage objects.

Author:

fracpete (fracpete at waikato dot ac dot nz)

Constructor Summary

Constructors

Constructor	Description
BufferedImageHelper()

Method Summary

Modifier and Type	Method	Description
static int	combine(int[] rgba)	Combines the R,G,B,A values back into single integer.
static int	combine(int r, int g, int b, int a)	Combines the R,G,B,A values back into single integer.
static BufferedImage	convert(BufferedImage img, int type)	Converts the image, if necessary to the specified type.
static BufferedImage	deepCopy(BufferedImage source)	Returns a copy of a BufferedImage object.
static boolean	floodFill(BufferedImage img, int startX, int startY, int targetColor, int replacementColor)	Performs flood fill on the image.
static boolean	floodFill(BufferedImage img, int startX, int startY, int targetColor, int replacementColor, int[] extent)	Performs flood fill on the image.
static boolean	floodFill(BufferedImage img, int startX, int startY, Color targetColor, Color replacementColor)	Performs flood fill on the image.
static boolean	floodFill(BufferedImage img, int startX, int startY, Color targetColor, Color replacementColor, int[] extent)	Performs flood fill on the image.
static BufferedImage	fromBytes(byte[] bytes, MessageCollection errors)	Turns the image bytes (eg JPG or PNG) into a BufferedImage.
static int	getPixelDepth(BufferedImage img)	Returns the pixel depth in bits.
static IntArrayMatrixView	getPixelMatrix(BufferedImage img)	Returns all the pixels of the image as an int array (row-wise).
static int[][]	getPixelRaster(BufferedImage img)	Returns the pixels of the image as an 2-D int array (row-wise).
static int[]	getPixels(BufferedImage img)	Returns all the pixels of the image as an int array (row-wise).
static ImageReader	getReaderForExtension(String ext)	Returns the first image reader that handles the specified extension.
static ImageReader	getReaderForFile(File file)	Returns the first image reader that handles the extension of the specified file.
static int[][]	getRGBPixels(BufferedImage img)	Returns all the pixels of the image as an int array (row-wise) with the RGB(A) components as second dimension.
static ImageWriter	getWriterForExtension(String ext)	Returns the first image writer that handles the extension of the specified file.
static ImageWriter	getWriterForFile(File file)	Returns the first image writer that handles the extension of the specified file.
static int[][]	histogram(BufferedImage img, boolean gray)	Generates a histogram for each of the R, G and B channels.
static BufferedImageContainer	read(File file)	Reads an image, also fills in meta-data.
static BufferedImageContainer	read(File file, boolean addMetaData)	Reads an image, also fills in meta-data.
static BufferedImageContainer	read(InputStream stream, boolean addMetaData)	Reads an image, also fills in meta-data.
static BufferedImage	removeAlphaChannel(BufferedImage img)	Removes the alpha channel if present and turns it into RGB image.
static BufferedImage	rotate(BufferedImage img, int degrees, Color background)	Rotates the images by the specified number of degrees.
static int[]	split(int pixel)	Splits the RGBA value into R,G,B,A.
static BufferedImage	toBufferedImage(JComponent comp, Color background)	Creates a BufferedImage from the component.
static BufferedImage	toBufferedImage(JComponent comp, Color background, int width, int height)	Creates a BufferedImage from the component.
static BufferedImageContainer	toBufferedImageContainer(AbstractImageContainer cont)	Creates a BufferedImageContainer container if necessary, otherwise it just casts the object.
static byte[]	toBytes(BufferedImage img, String format, MessageCollection errors)	Turns an image into a byte array.
static String	write(BufferedImage img, File file)	Writes the image to the specified file.
static String	write(BufferedImage img, String format, File file)	Writes the image to the specified file.
static String	write(BufferedImage img, String format, OutputStream stream)	Writes the image to the specified stream.

Methods inherited from class java.lang.Object

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

Constructor Detail

BufferedImageHelper

public BufferedImageHelper()

Method Detail

deepCopy

public static BufferedImage deepCopy(BufferedImage source)

Returns a copy of a BufferedImage object.

Taken from here (CC BY-SA 3.0). and from here (CC BY-SA 3.0).

Parameters:

source - the image to copy

getPixels

public static int[] getPixels(BufferedImage img)

Returns all the pixels of the image as an int array (row-wise).

Parameters:

img - the image to get the pixels from

Returns:

the pixel array

See Also:

BufferedImage.getRGB(int, int)

getPixelMatrix

public static IntArrayMatrixView getPixelMatrix(BufferedImage img)

Returns all the pixels of the image as an int array (row-wise).

Parameters:

img - the image to get the pixels from

Returns:

the pixel array

See Also:

BufferedImage.getRGB(int, int)

split

public static int[] split(int pixel)

Splits the RGBA value into R,G,B,A.

Parameters:

pixel - the RGB value to split

Returns:

the array with R,G,B,A

combine

public static int combine(int[] rgba)

Combines the R,G,B,A values back into single integer.

Parameters:

rgba - the RGBA values

Returns:

the combined integer

combine

public static int combine(int r,
                          int g,
                          int b,
                          int a)

Combines the R,G,B,A values back into single integer.

Parameters:

r - the red value

g - the green value

b - the blue value

a - the alpha value

Returns:

the combined integer

getRGBPixels

public static int[][] getRGBPixels(BufferedImage img)

Returns all the pixels of the image as an int array (row-wise) with the RGB(A) components as second dimension.

Parameters:

img - the image to get the pixels from

Returns:

the pixel array

See Also:

BufferedImage.getRGB(int, int)

getPixelRaster

public static int[][] getPixelRaster(BufferedImage img)

Returns the pixels of the image as an 2-D int array (row-wise).

Parameters:

img - the image to get the pixels from

Returns:

the pixel array

See Also:

BufferedImage.getRGB(int, int)

floodFill

public static boolean floodFill(BufferedImage img,
                                int startX,
                                int startY,
                                Color targetColor,
                                Color replacementColor)

Performs flood fill on the image. Based on the 2nd alternative implementation.

Parameters:

img - the image to perform the floodfill on

startX - the starting point, x coordinate

startY - the starting point, y coordinate

targetColor - the target color (what we want to fill)

replacementColor - the replacement color (the color fill with)

Returns:

true if successfully filled

floodFill

public static boolean floodFill(BufferedImage img,
                                int startX,
                                int startY,
                                int targetColor,
                                int replacementColor)

Performs flood fill on the image. Based on the 2nd alternative implementation.

Parameters:

img - the image to perform the floodfill on

startX - the starting point, x coordinate

startY - the starting point, y coordinate

targetColor - the target color (what we want to fill)

replacementColor - the replacement color (the color fill with)

Returns:

true if successfully filled

floodFill

public static boolean floodFill(BufferedImage img,
                                int startX,
                                int startY,
                                Color targetColor,
                                Color replacementColor,
                                int[] extent)

Performs flood fill on the image. Records the extent of the fill (bounding box). Based on the 2nd alternative implementation.

Parameters:

img - the image to perform the floodfill on

startX - the starting point, x coordinate

startY - the starting point, y coordinate

targetColor - the target color (what we want to fill)

replacementColor - the replacement color (the color fill with)

extent - for recording the bounding box for the flood fill, all -1 if failed to fill

Returns:

true if successfully filled

floodFill

public static boolean floodFill(BufferedImage img,
                                int startX,
                                int startY,
                                int targetColor,
                                int replacementColor,
                                int[] extent)

Performs flood fill on the image. Records the extent of the fill (bounding box). Based on the 2nd alternative implementation.

Parameters:

img - the image to perform the floodfill on

startX - the starting point, x coordinate

startY - the starting point, y coordinate

targetColor - the target color (what we want to fill)

replacementColor - the replacement color (the color fill with)

extent - for recording the bounding box for the flood fill, all -1 if failed to fill

Returns:

true if successfully filled

getReaderForFile

public static ImageReader getReaderForFile(File file)

Returns the first image reader that handles the extension of the specified file.

Parameters:

file - the file to get the reader for

Returns:

the reader, null if none found

getReaderForExtension

public static ImageReader getReaderForExtension(String ext)

Returns the first image reader that handles the specified extension.

Parameters:

ext - the extension to get the reader for

Returns:

the reader, null if none found

getWriterForFile

public static ImageWriter getWriterForFile(File file)

Returns the first image writer that handles the extension of the specified file.

Parameters:

file - the file to get the writer for

Returns:

the writer, null if none found

getWriterForExtension

public static ImageWriter getWriterForExtension(String ext)

Returns the first image writer that handles the extension of the specified file.

Parameters:

ext - the extension to get the writer for

Returns:

the writer, null if none found

read

public static BufferedImageContainer read(File file)

Reads an image, also fills in meta-data.

Parameters:

file - the file to read

Returns:

the image container, null if failed to read

read

public static BufferedImageContainer read(File file,
                                          boolean addMetaData)

Reads an image, also fills in meta-data.

Parameters:

file - the file to read

addMetaData - whether to add the meta-data

Returns:

the image container, null if failed to read

read

public static BufferedImageContainer read(InputStream stream,
                                          boolean addMetaData)

Reads an image, also fills in meta-data.

Parameters:

stream - the stream to read from

addMetaData - whether to add the meta-data

Returns:

the image container, null if failed to read

removeAlphaChannel

public static BufferedImage removeAlphaChannel(BufferedImage img)

Removes the alpha channel if present and turns it into RGB image.

Parameters:

img - the image to convert

Returns:

the (potentially) converted image

write

public static String write(BufferedImage img,
                           File file)

Writes the image to the specified file. If the output file points to a JPG file (.jpg or .jpeg), then images with alpha channel automatically get converted to RGB.

Parameters:

img - the image to save

file - the file to write to

Returns:

null if successful, otherwise error message

write

public static String write(BufferedImage img,
                           String format,
                           File file)

Writes the image to the specified file. If format is null, uses the file extension as format. If the format is JPG, then images with alpha channel automatically get converted to RGB.

Parameters:

img - the image to save

format - the image format to use (eg jpg or png), if null or empty uses extension as format

file - the file to write to

Returns:

null if successful, otherwise error message

write

public static String write(BufferedImage img,
                           String format,
                           OutputStream stream)

Writes the image to the specified stream.

Parameters:

img - the image to save

stream - the stream to write to

Returns:

null if successful, otherwise error message

toBytes

public static byte[] toBytes(BufferedImage img,
                             String format,
                             MessageCollection errors)

Turns an image into a byte array.

Parameters:

img - the image to convert

format - the format of the image, e.g., PNG or JPG

Returns:

the generated bytes, null if failed

fromBytes

public static BufferedImage fromBytes(byte[] bytes,
                                      MessageCollection errors)

Turns the image bytes (eg JPG or PNG) into a BufferedImage.

Parameters:

bytes - the bytes to convert

errors - for collecting errors

Returns:

the read image, null if failed to read

convert

public static BufferedImage convert(BufferedImage img,
                                    int type)

Converts the image, if necessary to the specified type.

Parameters:

img - the image to convert

type - the required type

Returns:

the (potentially) converted image

histogram

public static int[][] histogram(BufferedImage img,
                                boolean gray)

Generates a histogram for each of the R, G and B channels.

Parameters:

img - the image to analyze

gray - whether to use (A)RGB or grayscale

Returns:

the histogram, if ARGB then 0 = R, 1 = G, 2 = B, 3 = A or 0 = gray in case of grayscale

getPixelDepth

public static int getPixelDepth(BufferedImage img)

Returns the pixel depth in bits.

Parameters:

img - the image to analyze

Returns:

the number of bits, -1 if unknown type

toBufferedImageContainer

public static BufferedImageContainer toBufferedImageContainer(AbstractImageContainer cont)

Creates a BufferedImageContainer container if necessary, otherwise it just casts the object.

Parameters:

cont - the cont to cast/convert

Returns:

the casted/converted container

toBufferedImage

public static BufferedImage toBufferedImage(JComponent comp,
                                            Color background)

Creates a BufferedImage from the component.

Parameters:

comp - the component to turn into an image

background - the background

Returns:

the generated image

toBufferedImage

public static BufferedImage toBufferedImage(JComponent comp,
                                            Color background,
                                            int width,
                                            int height)

Creates a BufferedImage from the component.

Parameters:

comp - the component to turn into an image

background - the background

width - the width to use, -1 to use component width

height - the height to use, -1 to use component height

Returns:

the generated image

rotate

public static BufferedImage rotate(BufferedImage img,
                                   int degrees,
                                   Color background)

Rotates the images by the specified number of degrees.

Parameters:

img - the image to rotate

degrees - the rotation

background - the background color to use

Returns:

the rotated image