Package qupath.lib.images.servers

Class AbstractTileableImageServer

java.lang.Object

qupath.lib.images.servers.AbstractImageServer<BufferedImage>

qupath.lib.images.servers.AbstractTileableImageServer

All Implemented Interfaces:

AutoCloseable, ImageServer<BufferedImage>

Direct Known Subclasses:

BioFormatsImageServer, LabeledImageServer, OpenslideImageServer, PathHierarchyImageServer, PixelClassificationImageServer, RenderedImageServer, SparseImageServer, WrappedBufferedImageServer

public abstract class AbstractTileableImageServer
extends AbstractImageServer<BufferedImage>

Abstract ImageServer for BufferedImages that internally breaks up requests into constituent tiles.

The actual request is then handled by assembling the tiles, resizing as required. This makes it possible to cache tiles and reuse them more efficiently, and often requires less effort to implement a new ImageServer.

Author:

Pete Bankhead

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractTileableImageServer()

Method Summary

Modifier and Type	Method	Description
protected boolean	allowSmoothInterpolation()	Returns true if this server is permitted to use smooth interpolation when resizing.
protected BufferedImage	createDefaultRGBImage(int width, int height)	Create the default (blank) RGB image for this server.
protected ColorModel	getDefaultColorModel()	Get an appropriate colormodel that may be used.
protected BufferedImage	getEmptyTile(int width, int height)
protected BufferedImage	getEmptyTile(int width, int height, boolean doCache)	Create an empty tile for this server, using the default color model.
protected BufferedImage	getTile(TileRequest tileRequest)	Get a tile for the request - ideally from the cache, but otherwise read it and then add it to the cache.
BufferedImage	readRegion(RegionRequest request)	Read a 2D(+C) image region for a specified RegionRequest.
protected abstract BufferedImage	readTile(TileRequest tileRequest)	Read a single image tile.

Methods inherited from class qupath.lib.images.servers.AbstractImageServer

close, createID, createServerBuilder, finalize, getAssociatedImage, getAssociatedImageList, getBuilder, getCache, getCachedTile, getChannel, getDefaultThumbnail, getDownsampleForResolution, getHeight, getImageClass, getMetadata, getPath, getPixelType, getPreferredDownsamples, getThumbnailDownsampleFactor, getTileRequestManager, getWidth, isEmptyRegion, isRGB, nChannels, nResolutions, nTimepoints, nZSlices, setMetadata, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface qupath.lib.images.servers.ImageServer

getOriginalMetadata, getPixelCalibration, getServerType, getURIs, readBufferedImage, readRegion, readRegion

Constructor Details

AbstractTileableImageServer

protected AbstractTileableImageServer()

Method Details

getEmptyTile

protected BufferedImage getEmptyTile(int width,
 int height)
                              throws IOException

Throws:

IOException

getEmptyTile

protected BufferedImage getEmptyTile(int width,
 int height,
 boolean doCache)
                              throws IOException

Create an empty tile for this server, using the default color model.

Parameters:

width -

height -

doCache -

Returns:

Throws:

IOException

getDefaultColorModel

protected ColorModel getDefaultColorModel()
                                   throws IOException

Get an appropriate colormodel that may be used. The default implementation uses the default RGB color model for RGB images, or else requests a low-resolution thumbnail to extract the color model from it. If neither implementation is sufficient, subclasses should override this method.

Returns:

Throws:

IOException

readTile

protected abstract BufferedImage readTile(TileRequest tileRequest)
                                   throws IOException

Read a single image tile.

Parameters:

tileRequest -

Returns:

Throws:

IOException

getTile

protected BufferedImage getTile(TileRequest tileRequest)
                         throws IOException

Get a tile for the request - ideally from the cache, but otherwise read it and then add it to the cache.

Parameters:

tileRequest -

Returns:

Throws:

IOException

createDefaultRGBImage

protected BufferedImage createDefaultRGBImage(int width,
 int height)

Create the default (blank) RGB image for this server.

By default this will have TYPE_INT_RGB but a subclass may change this if necessary (e.g. to incorporate an alpha channel).

Parameters:

width -

height -

Returns:

readRegion

public BufferedImage readRegion(RegionRequest request)
                         throws IOException

Description copied from interface: ImageServer

Read a 2D(+C) image region for a specified RegionRequest. Coordinates and bounding box dimensions from the request are in pixel units, at the full image resolution (i.e. when downsample = 1).

All channels are always returned.

No specific checking is guaranteed to ensure that the request is valid, e.g. if it extends beyond the image boundary then it is likely (but not certain) that the returned image will be cropped accordingly - but some implementations may contain empty padding instead. Therefore it is up to the caller to ensure that the requests are within range.

However, it is expected that any returnable region will be at least 1x1 pixel in size, even if via high downsampling one might otherwise expect a 0x0 image. This is consistent with the idea of pixels representing point samples rather than little squares.

Note: One should avoid returning null, as this cannot be stored as a value in some map implementations that may be used for caching.

Parameters:

request - the region for which pixels are requested

Returns:

pixels for the region being requested

Throws:

IOException

See Also:

• ImageServer.readRegion(double, int, int, int, int, int, int)
• ImageServer.readRegion(double, int, int, int, int)
• ImageServer.readBufferedImage(RegionRequest)

allowSmoothInterpolation

protected boolean allowSmoothInterpolation()

Returns true if this server is permitted to use smooth interpolation when resizing. The default implementation returns true if the channel type is not ImageServerMetadata.ChannelType.CLASSIFICATION.

Returns: