DjvuImage
Contents
[
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]Inheritance: java.lang.Object, com.aspose.imaging.DisposableObject, com.aspose.imaging.DataStreamSupporter, com.aspose.imaging.Image, com.aspose.imaging.RasterImage, com.aspose.imaging.RasterCachedImage, com.aspose.imaging.RasterCachedMultipageImage
public final class DjvuImage extends RasterCachedMultipageImage
DjvuDocument class
Constructors
| Constructor | Description |
|---|---|
| DjvuImage(InputStream stream) | Initializes a new instance of the DjvuImage class. |
| DjvuImage(InputStream stream, LoadOptions loadOptions) | Initializes a new instance of the DjvuImage class. |
| DjvuImage(System.IO.Stream stream, LoadOptions loadOptions) | Initializes a new instance of the DjvuImage class. |
Fields
| Field | Description |
|---|---|
| PropertyChanged | Occurs when a property value changes. |
Methods
| Method | Description |
|---|---|
| getIdentifier() | Gets the unique identifier for the document |
| getPageCount() | Gets the page count. |
| getPages() | Gets the pages. |
| getDjvuPages() | Gets the pages for the document |
| getActivePage() | Gets or sets the currently active page |
| setActivePage(DjvuPage value) | Gets or sets the currently active page |
| getFirstPage() | Gets the first page of the document |
| getLastPage() | Gets the last page of the document |
| getNextPage() | Gets the next page of the document |
| getPreviousPage() | Gets the previous page of the document |
| getFileFormat() | Gets a value of file format |
| hasAlpha() | Gets the Has alpha channel. |
| loadDocument(InputStream stream) | Loads the document. |
| loadDocument(InputStream stream, LoadOptions loadOptions) | Loads the document. |
| rotate(float angle, boolean resizeProportionally, Color backgroundColor) | !:RasterCahcedMultipageImage.Rotate image around the center. |
| resize(int newWidth, int newHeight, int resizeType) | Resizes the image. |
| resizeWidthProportionally(int newWidth, int resizeType) | Resizes the width proportionally. |
| resizeHeightProportionally(int newHeight, int resizeType) | Resizes the width proportionally. |
| rotateFlip(int rotateFlipType) | Rotates, flips, or rotates and flips the Active frame only. |
| dither(int ditheringMethod, int bitsCount, IColorPalette customPalette) | Performs dithering on the current image. |
| crop(Rectangle rectangle) | Cropping the image. |
| crop(int leftShift, int rightShift, int topShift, int bottomShift) | Crop image with shifts. |
| binarizeFixed(byte threshold) | Binarization of an image with predefined threshold |
| binarizeOtsu() | Binarization of an image with Otsu thresholding |
| binarizeBradley(double brightnessDifference, int windowSize) | Binarization of an image using Bradley’s adaptive thresholding algorithm using the integral image thresholding |
| grayscale() | Transformation of an image to its grayscale representation |
| adjustGamma(float gamma) | Gamma-correction of an image. |
| adjustGamma(float gammaRed, float gammaGreen, float gammaBlue) | Gamma-correction of an image. |
| adjustBrightness(int brightness) | Adjust of a brightness for image. |
| adjustContrast(float contrast) | Image contrasting |
| filter(Rectangle rectangle, FilterOptionsBase options) | Filters the specified rectangle. |
| resize(int newWidth, int newHeight, ImageResizeSettings settings) | Resizes the image. |
| cacheData() | Caches the data private. |
Example: This example shows how to load a DJVU image from a file stream.
String dir = "c:\\temp\\";
// Load a DJVU image from a file stream.
java.io.InputStream stream = new java.io.FileInputStream(dir + "sample.djvu");
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = new com.aspose.imaging.fileformats.djvu.DjvuImage(stream);
try {
// Save each page as an individual PNG image.
for (com.aspose.imaging.fileformats.djvu.DjvuPage djvuPage : djvuImage.getPages()) {
// Generate a file name based on the page number.
String fileName = String.format("sample.%s.png", djvuPage.getPageNumber());
djvuPage.save(dir + fileName, new com.aspose.imaging.imageoptions.PngOptions());
}
} finally {
djvuImage.dispose();
stream.close();
}
DjvuImage(InputStream stream)
public DjvuImage(InputStream stream)
Initializes a new instance of the DjvuImage class.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| stream | java.io.InputStream | The stream. |
DjvuImage(InputStream stream, LoadOptions loadOptions)
public DjvuImage(InputStream stream, LoadOptions loadOptions)
Initializes a new instance of the DjvuImage class.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| stream | java.io.InputStream | The stream to load from. |
| loadOptions | LoadOptions | The load options. |
DjvuImage(System.IO.Stream stream, LoadOptions loadOptions)
public DjvuImage(System.IO.Stream stream, LoadOptions loadOptions)
Initializes a new instance of the DjvuImage class.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| stream | com.aspose.ms.System.IO.Stream | The stream. |
| loadOptions | LoadOptions | The load options. |
PropertyChanged
public final StdEvent<System.ComponentModel.PropertyChangedEventArgs> PropertyChanged
Occurs when a property value changes.
getIdentifier()
public int getIdentifier()
Gets the unique identifier for the document
Returns: int - The identifier.
getPageCount()
public int getPageCount()
Gets the page count.
Value: The page count.
Returns: int - the page count.
getPages()
public Image[] getPages()
Gets the pages.
Value: The pages.
Returns: com.aspose.imaging.Image[] - the pages.
Example: This example shows how to load a DJVU image from a file stream.
String dir = "c:\\temp\\";
// Load a DJVU image from a file stream.
java.io.InputStream stream = new java.io.FileInputStream(dir + "sample.djvu");
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = new com.aspose.imaging.fileformats.djvu.DjvuImage(stream);
try {
// Save each page as an individual PNG image.
for (com.aspose.imaging.fileformats.djvu.DjvuPage djvuPage : djvuImage.getPages()) {
// Generate a file name based on the page number.
String fileName = String.format("sample.%s.png", djvuPage.getPageNumber());
djvuPage.save(dir + fileName, new com.aspose.imaging.imageoptions.PngOptions());
}
} finally {
djvuImage.dispose();
stream.close();
}
getDjvuPages()
public DjvuPage[] getDjvuPages()
Gets the pages for the document
Value: The pages.
Returns: com.aspose.imaging.fileformats.djvu.DjvuPage[] - the pages for the document
getActivePage()
public DjvuPage getActivePage()
Gets or sets the currently active page
Returns: DjvuPage - The active page.
Example: This example shows how to load a DJVU image from a file stream and print information about the pages.
String dir = "c:\\temp\\";
// Load a DJVU image from a file stream.
java.io.FileInputStream stream = new java.io.FileInputStream(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = new com.aspose.imaging.fileformats.djvu.DjvuImage(stream);
try {
System.out.println("The total number of pages: " + djvuImage.getPages().length);
System.out.println("The active page number: " + djvuImage.getActivePage().getPageNumber());
System.out.println("The first page number: " + djvuImage.getFirstPage().getPageNumber());
System.out.println("The last page number: " + djvuImage.getLastPage().getPageNumber());
for (com.aspose.imaging.fileformats.djvu.DjvuPage djvuPage : djvuImage.getPages()) {
System.out.println("--------------------------------------------------");
System.out.println("Page number: " + djvuPage.getPageNumber());
System.out.println("Page size: " + djvuPage.getSize());
System.out.println("Page raw format: " + djvuPage.getRawDataFormat());
}
} finally {
djvuImage.dispose();
}
} finally {
stream.close();
}
//The output may look like this:
//The total number of pages: 2
//The active page number: 1
//The first page number: 1
//The last page number: 2
//--------------------------------------------------
//Page number: 1
//Page size: { Width = 2481, Height = 3508}
//Page raw format: RgbIndexed1Bpp, used channels: 1
//--------------------------------------------------
//Page number: 2
//Page size: { Width = 2481, Height = 3508}
//Page raw format: RgbIndexed1Bpp, used channels: 1
setActivePage(DjvuPage value)
public void setActivePage(DjvuPage value)
Gets or sets the currently active page
Parameters:
| Parameter | Type | Description |
|---|---|---|
| value | DjvuPage | The active page. |
getFirstPage()
public DjvuPage getFirstPage()
Gets the first page of the document
Returns: DjvuPage - The first page.
Example: This example shows how to load a DJVU image from a file stream and print information about the pages.
String dir = "c:\\temp\\";
// Load a DJVU image from a file stream.
java.io.FileInputStream stream = new java.io.FileInputStream(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = new com.aspose.imaging.fileformats.djvu.DjvuImage(stream);
try {
System.out.println("The total number of pages: " + djvuImage.getPages().length);
System.out.println("The active page number: " + djvuImage.getActivePage().getPageNumber());
System.out.println("The first page number: " + djvuImage.getFirstPage().getPageNumber());
System.out.println("The last page number: " + djvuImage.getLastPage().getPageNumber());
for (com.aspose.imaging.fileformats.djvu.DjvuPage djvuPage : djvuImage.getPages()) {
System.out.println("--------------------------------------------------");
System.out.println("Page number: " + djvuPage.getPageNumber());
System.out.println("Page size: " + djvuPage.getSize());
System.out.println("Page raw format: " + djvuPage.getRawDataFormat());
}
} finally {
djvuImage.dispose();
}
} finally {
stream.close();
}
//The output may look like this:
//The total number of pages: 2
//The active page number: 1
//The first page number: 1
//The last page number: 2
//--------------------------------------------------
//Page number: 1
//Page size: { Width = 2481, Height = 3508}
//Page raw format: RgbIndexed1Bpp, used channels: 1
//--------------------------------------------------
//Page number: 2
//Page size: { Width = 2481, Height = 3508}
//Page raw format: RgbIndexed1Bpp, used channels: 1
getLastPage()
public DjvuPage getLastPage()
Gets the last page of the document
Returns: DjvuPage - The last page.
Example: This example shows how to load a DJVU image from a file stream and print information about the pages.
String dir = "c:\\temp\\";
// Load a DJVU image from a file stream.
java.io.FileInputStream stream = new java.io.FileInputStream(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = new com.aspose.imaging.fileformats.djvu.DjvuImage(stream);
try {
System.out.println("The total number of pages: " + djvuImage.getPages().length);
System.out.println("The active page number: " + djvuImage.getActivePage().getPageNumber());
System.out.println("The first page number: " + djvuImage.getFirstPage().getPageNumber());
System.out.println("The last page number: " + djvuImage.getLastPage().getPageNumber());
for (com.aspose.imaging.fileformats.djvu.DjvuPage djvuPage : djvuImage.getPages()) {
System.out.println("--------------------------------------------------");
System.out.println("Page number: " + djvuPage.getPageNumber());
System.out.println("Page size: " + djvuPage.getSize());
System.out.println("Page raw format: " + djvuPage.getRawDataFormat());
}
} finally {
djvuImage.dispose();
}
} finally {
stream.close();
}
//The output may look like this:
//The total number of pages: 2
//The active page number: 1
//The first page number: 1
//The last page number: 2
//--------------------------------------------------
//Page number: 1
//Page size: { Width = 2481, Height = 3508}
//Page raw format: RgbIndexed1Bpp, used channels: 1
//--------------------------------------------------
//Page number: 2
//Page size: { Width = 2481, Height = 3508}
//Page raw format: RgbIndexed1Bpp, used channels: 1
getNextPage()
public DjvuPage getNextPage()
Gets the next page of the document
Returns: DjvuPage - The next page.
getPreviousPage()
public DjvuPage getPreviousPage()
Gets the previous page of the document
Returns: DjvuPage - The previous page.
getFileFormat()
public long getFileFormat()
Gets a value of file format
Returns: long
hasAlpha()
public boolean hasAlpha()
Gets the Has alpha channel.
Value: The Has alpha channel.
Returns: boolean - the Has alpha channel.
loadDocument(InputStream stream)
public static DjvuImage loadDocument(InputStream stream)
Loads the document.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| stream | java.io.InputStream | The stream. |
Returns: DjvuImage - Loaded djvu document
loadDocument(InputStream stream, LoadOptions loadOptions)
public static DjvuImage loadDocument(InputStream stream, LoadOptions loadOptions)
Loads the document.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| stream | java.io.InputStream | The stream. |
| loadOptions | LoadOptions | The load options. |
Returns: DjvuImage - Loaded djvu document
rotate(float angle, boolean resizeProportionally, Color backgroundColor)
public void rotate(float angle, boolean resizeProportionally, Color backgroundColor)
!:RasterCahcedMultipageImage.Rotate image around the center.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| angle | float | The rotate angle in degrees. Positive values will rotate clockwise. |
| resizeProportionally | boolean | if set to true you will have your image size changed according to rotated rectangle (corner points) projections in other case that leaves dimensions untouched and only `` image contents are rotated. |
| backgroundColor | Color | Color of the background. |
resize(int newWidth, int newHeight, int resizeType)
public void resize(int newWidth, int newHeight, int resizeType)
Resizes the image.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| newWidth | int | The new width. |
| newHeight | int | The new height. |
| resizeType | int | The resize type. |
Example: This example loads a DJVU image and resizes it using various resizing methods.
String dir = "c:\\temp\\";
com.aspose.imaging.fileformats.djvu.DjvuImage image = (com.aspose.imaging.fileformats.djvu.DjvuImage) com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
// Scale up by 2 times using Nearest Neighbour resampling.
image.resize(image.getWidth() * 2, image.getHeight() * 2, com.aspose.imaging.ResizeType.NearestNeighbourResample);
// Save to PNG with default options.
image.save(dir + "upsample.nearestneighbour.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
image = (com.aspose.imaging.fileformats.djvu.DjvuImage) com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
// Scale down by 2 times using Nearest Neighbour resampling.
image.resize(image.getWidth() / 2, image.getHeight() / 2, com.aspose.imaging.ResizeType.NearestNeighbourResample);
// Save to PNG with default options.
image.save(dir + "downsample.nearestneighbour.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
image = (com.aspose.imaging.fileformats.djvu.DjvuImage) com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
// Scale up by 2 times using Bilinear resampling.
image.resize(image.getWidth() * 2, image.getHeight() * 2, com.aspose.imaging.ResizeType.BilinearResample);
// Save to PNG with default options.
image.save(dir + "upsample.bilinear.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
image = (com.aspose.imaging.fileformats.djvu.DjvuImage) com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
// Scale down by 2 times using Bilinear resampling.
image.resize(image.getWidth() / 2, image.getHeight() / 2, com.aspose.imaging.ResizeType.BilinearResample);
// Save to PNG with default options.
image.save(dir + "downsample.bilinear.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
resizeWidthProportionally(int newWidth, int resizeType)
public void resizeWidthProportionally(int newWidth, int resizeType)
Resizes the width proportionally.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| newWidth | int | The new width. |
| resizeType | int | Type of the resize. |
Example: This example loads a DJVU image and resizes it proportionally using various resizing methods. This example loads a DJVU image and resizes it proportionally using various resizing methods. Only the width is specified, the height is calculated automatically.
String dir = "c:\\temp\\";
com.aspose.imaging.fileformats.djvu.DjvuImage image = (com.aspose.imaging.fileformats.djvu.DjvuImage) com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
// Scale up by 2 times using Nearest Neighbour resampling.
image.resizeWidthProportionally(image.getWidth() * 2, com.aspose.imaging.ResizeType.NearestNeighbourResample);
// Save to PNG with the default options.
image.save(dir + "upsample.nearestneighbour.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
image = (com.aspose.imaging.fileformats.djvu.DjvuImage) com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
// Scale down by 2 times using Nearest Neighbour resampling.
image.resizeWidthProportionally(image.getWidth() / 2, com.aspose.imaging.ResizeType.NearestNeighbourResample);
// Save to PNG with the default options.
image.save(dir + "downsample.nearestneighbour.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
image = (com.aspose.imaging.fileformats.djvu.DjvuImage) com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
// Scale up by 2 times using Bilinear resampling.
image.resizeWidthProportionally(image.getWidth() * 2, com.aspose.imaging.ResizeType.BilinearResample);
// Save to PNG with the default options.
image.save(dir + "upsample.bilinear.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
image = (com.aspose.imaging.fileformats.djvu.DjvuImage) com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
// Scale down by 2 times using Bilinear resampling.
image.resizeWidthProportionally(image.getWidth() / 2, com.aspose.imaging.ResizeType.BilinearResample);
// Save to PNG with the default options.
image.save(dir + "downsample.bilinear.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
resizeHeightProportionally(int newHeight, int resizeType)
public void resizeHeightProportionally(int newHeight, int resizeType)
Resizes the width proportionally.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| newHeight | int | The new height. |
| resizeType | int | Type of the resize. |
Example: This example loads a DJVU image and resizes it proportionally using various resizing methods. This example loads a DJVU image and resizes it proportionally using various resizing methods. Only the height is specified, the width is calculated automatically.
String dir = "c:\\temp\\";
com.aspose.imaging.fileformats.djvu.DjvuImage image = (com.aspose.imaging.fileformats.djvu.DjvuImage) com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
// Scale up by 2 times using Nearest Neighbour resampling.
image.resizeHeightProportionally(image.getHeight() * 2, com.aspose.imaging.ResizeType.NearestNeighbourResample);
// Save to PNG with the default options.
image.save(dir + "upsample.nearestneighbour.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
image = (com.aspose.imaging.fileformats.djvu.DjvuImage) com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
// Scale down by 2 times using Nearest Neighbour resampling.
image.resizeHeightProportionally(image.getHeight() / 2, com.aspose.imaging.ResizeType.NearestNeighbourResample);
// Save to PNG with the default options.
image.save(dir + "downsample.nearestneighbour.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
image = (com.aspose.imaging.fileformats.djvu.DjvuImage) com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
// Scale up by 2 times using Bilinear resampling.
image.resizeHeightProportionally(image.getHeight() * 2, com.aspose.imaging.ResizeType.BilinearResample);
// Save to PNG with the default options.
image.save(dir + "upsample.bilinear.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
image = (com.aspose.imaging.fileformats.djvu.DjvuImage) com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
// Scale down by 2 times using Bilinear resampling.
image.resizeHeightProportionally(image.getHeight() / 2, com.aspose.imaging.ResizeType.BilinearResample);
// Save to PNG with the default options.
image.save(dir + "downsample.bilinear.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
rotateFlip(int rotateFlipType)
public void rotateFlip(int rotateFlipType)
Rotates, flips, or rotates and flips the Active frame only.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| rotateFlipType | int | The rotate flip type. |
Example: This example loads a DJVU image, rotates it by 90 degrees clockwise and optionally flips the image horizontally and(or) vertically.
String dir = "c:\\temp\\";
int[] rotateFlipTypes = new int[]
{
com.aspose.imaging.RotateFlipType.Rotate90FlipNone,
com.aspose.imaging.RotateFlipType.Rotate90FlipX,
com.aspose.imaging.RotateFlipType.Rotate90FlipXY,
com.aspose.imaging.RotateFlipType.Rotate90FlipY,
};
for (int rotateFlipType : rotateFlipTypes) {
// Rotate, flip and save to the output file.
com.aspose.imaging.fileformats.djvu.DjvuImage image = (com.aspose.imaging.fileformats.djvu.DjvuImage) com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
image.rotateFlip(rotateFlipType);
image.save(dir + "sample." + rotateFlipType + ".png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
}
dither(int ditheringMethod, int bitsCount, IColorPalette customPalette)
public void dither(int ditheringMethod, int bitsCount, IColorPalette customPalette)
Performs dithering on the current image.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| ditheringMethod | int | The dithering method. |
| bitsCount | int | The final bits count for dithering. |
| customPalette | IColorPalette | The custom palette for dithering. |
Example: The following example loads a DJVU image and performs threshold and floyd dithering using different palette depth.
String dir = "c:\\temp\\";
com.aspose.imaging.Image image = com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage dicomImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
// Perform threshold dithering using 4-bit color palette which contains 16 colors.
// The more bits specified the higher quality and the bigger size of the output image.
// Note that only 1-bit, 4-bit and 8-bit palettes are supported at the moment.
dicomImage.dither(com.aspose.imaging.DitheringMethod.ThresholdDithering, 4, null);
dicomImage.save(dir + "sample.ThresholdDithering4.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
image = com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage dicomImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
// Perform floyd dithering using 1-bit color palette which contains only 2 colors - black and white.
// The more bits specified the higher quality and the bigger size of the output image.
// Note that only 1-bit, 4-bit and 8-bit palettes are supported at the moment.
dicomImage.dither(com.aspose.imaging.DitheringMethod.FloydSteinbergDithering, 1, null);
dicomImage.save(dir + "sample.FloydSteinbergDithering1.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
crop(Rectangle rectangle)
public void crop(Rectangle rectangle)
Cropping the image.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| rectangle | Rectangle | The rectangle. |
Example: The following example crops a DJVU image. The following example crops a DJVU image. The cropping area is be specified via Aspose.Imaging.Rectangle.
String dir = "c:\\temp\\";
com.aspose.imaging.Image image = com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
// Crop the image. The cropping area is the rectangular central area of the image.
com.aspose.imaging.Rectangle area = new com.aspose.imaging.Rectangle(
djvuImage.getWidth() / 4, djvuImage.getHeight() / 4, djvuImage.getWidth() / 2, djvuImage.getHeight() / 2);
djvuImage.crop(area);
// Save the cropped image to PNG
djvuImage.save(dir + "sample.Crop.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
crop(int leftShift, int rightShift, int topShift, int bottomShift)
public void crop(int leftShift, int rightShift, int topShift, int bottomShift)
Crop image with shifts.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| leftShift | int | The left shift. |
| rightShift | int | The right shift. |
| topShift | int | The top shift. |
| bottomShift | int | The bottom shift. |
binarizeFixed(byte threshold)
public void binarizeFixed(byte threshold)
Binarization of an image with predefined threshold
Parameters:
| Parameter | Type | Description |
|---|---|---|
| threshold | byte | Threshold value. If corresponding gray value of a pixel is greater than threshold, a value of 255 will be assigned to it, 0 otherwise. |
Example: The following example binarizes a DJVU image with the predefined threshold. The following example binarizes a DJVU image with the predefined threshold. Binarized images contain only 2 colors - black and white.
String dir = "c:\\temp\\";
com.aspose.imaging.Image image = com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
// Binarize the image with a threshold value of 127.
// If a corresponding gray value of a pixel is greater than 127, a value of 255 will be assigned to it, 0 otherwise.
djvuImage.binarizeFixed((byte) 127);
djvuImage.save(dir + "sample.BinarizeFixed.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
binarizeOtsu()
public void binarizeOtsu()
Binarization of an image with Otsu thresholding
Example: The following example binarizes a DJVU image with Otsu thresholding. The following example binarizes a DJVU image with Otsu thresholding. Binarized images contain only 2 colors - black and white.
String dir = "c:\\temp\\";
com.aspose.imaging.Image image = com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
// Binarize the image with Otsu thresholding.
djvuImage.binarizeOtsu();
djvuImage.save(dir + "sample.BinarizeOtsu.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
binarizeBradley(double brightnessDifference, int windowSize)
public void binarizeBradley(double brightnessDifference, int windowSize)
Binarization of an image using Bradley’s adaptive thresholding algorithm using the integral image thresholding
Parameters:
| Parameter | Type | Description |
|---|---|---|
| brightnessDifference | double | The brightness difference between pixel and the average of an s x s window of pixels centered around this pixel. |
| windowSize | int | The size of s x s window of pixels centered around this pixel |
Example: The following example binarizes a DJVU image with Bradley’s adaptive thresholding algorithm with the specified window size. The following example binarizes a DJVU image with Bradley’s adaptive thresholding algorithm with the specified window size. Binarized images contain only 2 colors - black and white.
String dir = "c:\\temp\\";
com.aspose.imaging.Image image = com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
// Binarize the image with a brightness difference of 5. The brightness is a difference between a pixel and the average of an 10 x 10 window of pixels centered around this pixel.
djvuImage.binarizeBradley(5, 10);
djvuImage.save(dir + "sample.BinarizeBradley5_10x10.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
grayscale()
public void grayscale()
Transformation of an image to its grayscale representation
Example: The following example transforms a colored DJVU image to its grayscale representation. The following example transforms a colored DJVU image to its grayscale representation. Grayscale images are composed exclusively of shades of gray and carry only intensity information.
String dir = "c:\\temp\\";
com.aspose.imaging.Image image = com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
djvuImage.grayscale();
djvuImage.save(dir + "sample.Grayscale.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
adjustGamma(float gamma)
public void adjustGamma(float gamma)
Gamma-correction of an image.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| gamma | float | Gamma for red, green and blue channels coefficient |
Example: The following example performs gamma-correction of a DJVU image.
String dir = "c:\\temp\\";
com.aspose.imaging.Image image = com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
// Set gamma coefficient for red, green and blue channels.
djvuImage.adjustGamma(2.5f);
djvuImage.save(dir + "sample.AdjustGamma.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
adjustGamma(float gammaRed, float gammaGreen, float gammaBlue)
public void adjustGamma(float gammaRed, float gammaGreen, float gammaBlue)
Gamma-correction of an image.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| gammaRed | float | Gamma for red channel coefficient |
| gammaGreen | float | Gamma for green channel coefficient |
| gammaBlue | float | Gamma for blue channel coefficient |
Example: The following example performs gamma-correction of a DJVU image applying different coefficients for color components.
String dir = "c:\\temp\\";
com.aspose.imaging.Image image = com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
// Set individual gamma coefficients for red, green and blue channels.
djvuImage.adjustGamma(1.5f, 2.5f, 3.5f);
djvuImage.save(dir + "sample.AdjustGamma.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
adjustBrightness(int brightness)
public void adjustBrightness(int brightness)
Adjust of a brightness for image.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| brightness | int | Brightness value. |
Example: The following example performs brightness correction of a DJVU image.
String dir = "c:\\temp\\";
com.aspose.imaging.Image image = com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
// Set the brightness value. The accepted values of brightness are in the range [-255, 255].
djvuImage.adjustBrightness(50);
djvuImage.save(dir + "sample.AdjustBrightness.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
adjustContrast(float contrast)
public void adjustContrast(float contrast)
Image contrasting
Parameters:
| Parameter | Type | Description |
|---|---|---|
| contrast | float | Contrast value (in range [-100; 100]) |
Example: The following example performs contrast correction of a DJVU image.
String dir = "c:\\temp\\";
com.aspose.imaging.Image image = com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
// Set the contrast value. The accepted values of contrast are in the range [-100f, 100f].
djvuImage.adjustContrast(50f);
djvuImage.save(dir + "sample.AdjustContrast.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
filter(Rectangle rectangle, FilterOptionsBase options)
public void filter(Rectangle rectangle, FilterOptionsBase options)
Filters the specified rectangle.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| rectangle | Rectangle | The rectangle. |
| options | FilterOptionsBase | The options. |
Example: The following example applies various types of filters to a DJVU image.
String dir = "c:\\temp\\";
com.aspose.imaging.Image image = com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
// Apply a median filter with a rectangle size of 5 to the entire image.
djvuImage.filter(djvuImage.getBounds(), new com.aspose.imaging.imagefilters.filteroptions.MedianFilterOptions(5));
djvuImage.save(dir + "sample.MedianFilter.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
image = com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
// Apply a bilateral smoothing filter with a kernel size of 5 to the entire image.
djvuImage.filter(djvuImage.getBounds(), new com.aspose.imaging.imagefilters.filteroptions.BilateralSmoothingFilterOptions(5));
djvuImage.save(dir + "sample.BilateralSmoothingFilter.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
image = com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
// Apply a Gaussian blur filter with a radius of 5 and a sigma value of 4.0 to the entire image.
djvuImage.filter(djvuImage.getBounds(), new com.aspose.imaging.imagefilters.filteroptions.GaussianBlurFilterOptions(5, 4.0));
djvuImage.save(dir + "sample.GaussianBlurFilter.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
image = com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
// Apply a Gauss-Wiener filter with a radius of 5 and a smooth value of 4.0 to the entire image.
djvuImage.filter(djvuImage.getBounds(), new com.aspose.imaging.imagefilters.filteroptions.GaussWienerFilterOptions(5, 4.0));
djvuImage.save(dir + "sample.GaussWienerFilter.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
image = com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
// Apply a motion wiener filter with a length of 5, a smooth value of 4.0 and an angle of 90.0 degrees to the entire image.
djvuImage.filter(djvuImage.getBounds(), new com.aspose.imaging.imagefilters.filteroptions.MotionWienerFilterOptions(10, 1.0, 90.0));
djvuImage.save(dir + "sample.MotionWienerFilter.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
image = com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
// Apply a sharpen filter with a kernel size of 5 and a sigma value of 4.0 to the entire image.
djvuImage.filter(djvuImage.getBounds(), new com.aspose.imaging.imagefilters.filteroptions.SharpenFilterOptions(5, 4.0));
djvuImage.save(dir + "sample.SharpenFilter.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
resize(int newWidth, int newHeight, ImageResizeSettings settings)
public void resize(int newWidth, int newHeight, ImageResizeSettings settings)
Resizes the image.
Parameters:
| Parameter | Type | Description |
|---|---|---|
| newWidth | int | The new width. |
| newHeight | int | The new height. |
| settings | ImageResizeSettings | The resize settings. |
Example: This example loads a DJVU image and resizes it using various resizing settings.
String dir = "c:\\temp\\";
com.aspose.imaging.ImageResizeSettings resizeSettings = new com.aspose.imaging.ImageResizeSettings();
// The adaptive algorithm based on weighted and blended rational function and lanczos3 interpolation.
resizeSettings.setMode(com.aspose.imaging.ResizeType.AdaptiveResample);
// The small rectangular filter
resizeSettings.setFilterType(com.aspose.imaging.ImageFilterType.SmallRectangular);
// The number of colors in the palette.
resizeSettings.setEntriesCount(256);
// The color quantization is not used
resizeSettings.setColorQuantizationMethod(com.aspose.imaging.ColorQuantizationMethod.None);
// The euclidian method
resizeSettings.setColorCompareMethod(com.aspose.imaging.ColorCompareMethod.Euclidian);
com.aspose.imaging.Image image = (com.aspose.imaging.Image) com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
com.aspose.imaging.fileformats.djvu.DjvuImage djvuImage = (com.aspose.imaging.fileformats.djvu.DjvuImage) image;
// Scale down by 2 times using adaptive resampling.
djvuImage.resize(image.getWidth() / 2, image.getHeight() / 2, resizeSettings);
// Save to PNG
djvuImage.save(dir + "downsample.adaptive.png", new com.aspose.imaging.imageoptions.PngOptions());
} finally {
image.dispose();
}
cacheData()
public void cacheData()
Caches the data private.
Example: The following example shows how to cache all pages of a DJVU image.
String dir = "c:\\temp\\";
// Load an image from a DJVU file.
com.aspose.imaging.fileformats.djvu.DjvuImage image = (com.aspose.imaging.fileformats.djvu.DjvuImage) com.aspose.imaging.Image.load(dir + "sample.djvu");
try {
// This call caches all the pages so that no additional data loading will be performed from the underlying data stream.
image.cacheData();
// Or you can cache the pages individually.
for (com.aspose.imaging.fileformats.djvu.DjvuPage page : image.getPages()) {
page.cacheData();
}
} finally {
image.dispose();
}