org.apache.batik.transcoder.image
public abstract class ImageTranscoder extends SVGAbstractTranscoder
Two transcoding hints (KEY_WIDTH and KEY_HEIGHT) can be used to respectively specify the image width and the image height. If only one of these keys is specified, the transcoder preserves the aspect ratio of the original image.
The KEY_BACKGROUND_COLOR defines the background color to use for opaque image formats, or the background color that may be used for image formats that support alpha channel.
The KEY_AOI represents the area of interest to paint in device space.
Three additional transcoding hints that act on the SVG processor can be specified:
KEY_LANGUAGE to set the default language to use (may be used by a <switch> SVG element for example), KEY_USER_STYLESHEET_URI to fix the URI of a user stylesheet, and KEY_MM_PER_PIXEL to specify the number of millimeters in each pixel .
Field Summary | |
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static TranscodingHints.Key | KEY_BACKGROUND_COLOR
The image background paint key.
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static TranscodingHints.Key | KEY_FORCE_TRANSPARENT_WHITE
The forceTransparentWhite key.
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Constructor Summary | |
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protected | ImageTranscoder()
Constructs a new ImageTranscoder. |
Method Summary | |
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abstract BufferedImage | createImage(int width, int height)
Creates a new image with the specified dimension. |
protected ImageRenderer | createRenderer()
Method so subclasses can modify the Renderer used to render document. |
protected void | forceTransparentWhite(BufferedImage img, SinglePixelPackedSampleModel sppsm)
Converts an image so that viewers which do not support the
alpha channel will see a white background (and not a black
one). |
protected void | transcode(Document document, String uri, TranscoderOutput output)
Transcodes the specified Document as an image in the specified output.
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abstract void | writeImage(BufferedImage img, TranscoderOutput output)
Writes the specified image to the specified output. |
Key: |
KEY_BACKGROUND_COLOR |
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Value: |
Paint |
Default: |
null |
Required: |
No |
Description: |
Specify the background color to use. The color is required by opaque image formats and is used by image formats that support alpha channel. |
Key: |
KEY_FORCE_TRANSPARENT_WHITE |
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Value: |
Boolean |
Default: |
false |
Required: |
No |
Description: |
It controls whether the encoder should force
the image's fully transparent pixels to be fully transparent
white instead of fully transparent black. This is usefull when
the encoded file is displayed in a browser which does not
support transparency correctly and lets the image display with
a white background instead of a black background. However, note that the modified image will display differently over a white background in a viewer that supports transparency. Not all Transcoders use this key (in particular some formats can't preserve the alpha channel at all in which case this is not used. |
Parameters: width the image width in pixels height the image height in pixels
Parameters: img the image to convert sppsm
Parameters: document the document to transcode uri the uri of the document or null if any output the ouput where to transcode
Throws: TranscoderException if an error occured while transcoding
Parameters: img the image to write output the output where to store the image
Throws: TranscoderException if an error occured while storing the image