Activates the installed IIOParamController for this IIOParam object and returns the resulting value.

  Activates the installed IIOParamController for this IIOParam object and returns the resulting value. When this method returns true, all values for this IIOParam object will be ready for the next read or write operation. If false is returned, no settings in this object will have been disturbed (i.e., the user canceled the operation).

Ordinarily, the controller will be a GUI providing a user interface for a subclass of IIOParam for a particular plug-in. Controllers need not be GUIs, however.
Returns: true if the controller completed normally.
Throws:
- IllegalStateException - if there is no controller currently installed.
See Also: IIOParamController, IIOParam.setController(IIOParamController), IIOParam.getController(), IIOParam.getDefaultController(), IIOParam.hasController(),

  Returns true if the writer can perform tiling with non-zero grid offsets while writing.

  Returns true if the writer can perform tiling with
non-zero grid offsets while writing. If this method returns
false, then setTiling will throw an
UnsupportedOperationException if the grid offset
arguments are not both zero. If canWriteTiles
returns false, this method will return
false as well.
Returns: true if the writer supports non-zero tile offsets.
See Also: ImageWriteParam.canWriteTiles(), ImageWriteParam.setTiling(int, int, int, int),

  Returns true if this writer supports compression.

  Returns true if this writer supports compression.
Returns: true if the writer supports compression.

  Returns true if the writer can write out images as a series of passes of progressively increasing quality.

  Returns true if the writer can write out images
as a series of passes of progressively increasing quality.
Returns: true if the writer supports progressive encoding.
See Also: ImageWriteParam.setProgressiveMode(int), ImageWriteParam.getProgressiveMode(),

  Returns true if the writer can perform tiling while writing.

  Returns true if the writer can perform tiling
while writing. If this method returns false, then
setTiling will throw an
UnsupportedOperationException.
Returns: true if the writer supports tiling.
See Also: ImageWriteParam.canOffsetTiles(), ImageWriteParam.setTiling(int, int, int, int),

  Returns a float indicating an estimate of the number of bits of output data for each bit of input image data at the given quality level.

  Returns a float indicating an estimate of the number of bits of output data for each bit of input image data at the given quality level. The value will typically lie between 0 and 1, with smaller values indicating more compression. A special value of -1.0F is used to indicate that no estimate is available.

If there are multiple compression types but none has been set, an IllegalStateException is thrown.

The default implementation checks that compression is supported and the compression mode is MODE_EXPLICIT. If so, if getCompressionTypes() is null or getCompressionType() is non-null, and quality is within bounds, it returns -1.0.
Returns: an estimate of the compressed bit rate, or -1.0F if no estimate is available.
Parameters:
- quality - the quality setting whose bit rate is to be queried.
Throws:
- UnsupportedOperationException - if the writer does not support compression.
- IllegalStateException - if the compression mode is not MODE_EXPLICIT.
- IllegalStateException - if the set of legal compression types is non-null and the current compression type is null.
- IllegalArgumentException - if quality is not between 0and 1, inclusive.

  Returns the current compression mode, if compression is supported.

  Returns the current compression mode, if compression is
supported.
Returns: the current compression mode.
Throws:
- UnsupportedOperationException - if the writer does not support compression.
See Also: ImageWriteParam.setCompressionMode(int),

  Returns the current compression quality setting.

  Returns the current compression quality setting.

If there are multiple compression types but none has been set, an IllegalStateException is thrown.

The default implementation checks that compression is supported and that the compression mode is MODE_EXPLICIT. If so, if getCompressionTypes() is null or getCompressionType() is non-null, it returns the value of the compressionQuality instance variable.
Returns: the current compression quality setting.
Throws:
- UnsupportedOperationException - if the writer does not support compression.
- IllegalStateException - if the compression mode is not MODE_EXPLICIT.
- IllegalStateException - if the set of legal compression types is non-null and the current compression type is null.
See Also: ImageWriteParam.setCompressionQuality(float),

  Returns an array of Strings that may be used along with getCompressionQualityValues as part of a user interface for setting or displaying the compression quality level.

  Returns an array of Strings that may be used along with getCompressionQualityValues as part of a user interface for setting or displaying the compression quality level. The String with index i provides a description of the range of quality levels between getCompressionQualityValues[i] and getCompressionQualityValues[i + 1]. Note that the length of the array returned from getCompressionQualityValues will always be one greater than that returned from getCompressionQualityDescriptions.

As an example, the strings "Good", "Better", and "Best" could be associated with the ranges [0, .33), [.33, .66), and [.66, 1.0]. In this case, getCompressionQualityDescriptions would return { "Good", "Better", "Best" } and getCompressionQualityValues would return { 0.0F, .33F, .66F, 1.0F }.

If no descriptions are available, null is returned. If null is returned from getCompressionQualityValues, this method must also return null.

The descriptions should be localized for the Locale returned by getLocale, if it is non-null.

If there are multiple compression types but none has been set, an IllegalStateException is thrown.

The default implementation checks that compression is supported and that the compression mode is MODE_EXPLICIT. If so, if getCompressionTypes() is null or getCompressionType() is non-null, it returns null.
Returns: an array of Strings containing localized descriptions of the compression quality levels.
Throws:
- UnsupportedOperationException - if the writer does not support compression.
- IllegalStateException - if the compression mode is not MODE_EXPLICIT.
- IllegalStateException - if the set of legal compression types is non-null and the current compression type is null.
See Also: ImageWriteParam.getCompressionQualityValues(),

  Returns an array of floats that may be used along with getCompressionQualityDescriptions as part of a user interface for setting or displaying the compression quality level.

  Returns an array of floats that may be used along with getCompressionQualityDescriptions as part of a user interface for setting or displaying the compression quality level. See getCompressionQualityDescriptions for more information.

If no descriptions are available, null is returned. If null is returned from getCompressionQualityDescriptions, this method must also return null.

If there are multiple compression types but none has been set, an IllegalStateException is thrown.

The default implementation checks that compression is supported and that the compression mode is MODE_EXPLICIT. If so, if getCompressionTypes() is null or getCompressionType() is non-null, it returns null.
Returns: an array of floats indicating the boundaries between the compression quality levels as described by the Strings from getCompressionQualityDescriptions.
Throws:
- UnsupportedOperationException - if the writer does not support compression.
- IllegalStateException - if the compression mode is not MODE_EXPLICIT.
- IllegalStateException - if the set of legal compression types is non-null and the current compression type is null.
See Also: ImageWriteParam.getCompressionQualityDescriptions(),

  Returns the currently set compression type, or null if none has been set.

  Returns the currently set compression type, or null if none has been set. The type is returned as a String from among those returned by getCompressionTypes. If no compression type has been set, null is returned.

The default implementation checks whether compression is supported and the compression mode is MODE_EXPLICIT. If so, it returns the value of the compressionType instance variable.
Returns: the current compression type as a String, or null if no type is set.
Throws:
- UnsupportedOperationException - if the writer does not support compression.
- IllegalStateException - if the compression mode is not MODE_EXPLICIT.
See Also: ImageWriteParam.setCompressionType(java.lang.String),

  Returns a list of available compression types, as an array or Strings, or null if a compression type may not be chosen using these interfaces.

  Returns a list of available compression types, as an array or Strings, or null if a compression type may not be chosen using these interfaces. The array returned is a copy.

If the writer only offers a single, mandatory form of compression, it is not necessary to provide any named compression types. Named compression types should only be used where the user is able to make a meaningful choice between different schemes.

The default implementation checks if compression is supported and throws an UnsupportedOperationException if not. Otherwise, it returns a clone of the compressionTypes instance variable if it is non-null, or else returns null.
Returns: an array of Strings containing the (non-localized) names of available compression types, or null.
Throws:
- UnsupportedOperationException - if the writer does not support compression.

  Returns whatever IIOParamController is currently installed.

  Returns whatever IIOParamController is currently
installed. This could be the default if there is one,
null, or the argument of the most recent call
to setController.
Returns: the currently installed IIOParamController, or null.
See Also: IIOParamController, IIOParam.setController(javax.imageio.IIOParamController), IIOParam.getDefaultController(), IIOParam.hasController(), IIOParam.activateController(),

  Returns the default IIOParamController, if there is one, regardless of the currently installed controller.

  Returns the default IIOParamController, if there
is one, regardless of the currently installed controller. If
there is no default controller, returns null.
Returns: the default IIOParamController, or null.
See Also: IIOParamController, IIOParam.setController(IIOParamController), IIOParam.getController(), IIOParam.hasController(), IIOParam.activateController(),

  Returns the offset in the destination image at which pixels are to be placed.

  Returns the offset in the destination image at which pixels are to be placed.

If setDestinationOffsets has not been called, a Point with zero X and Y values is returned (which is the correct value).
Returns: the destination offset as a Point.
See Also: IIOParam.setDestinationOffset(java.awt.Point),

  Returns the type of image to be returned by the read, if one was set by a call to setDestination(ImageTypeSpecifier), as an ImageTypeSpecifier.

  Returns the type of image to be returned by the read, if one
was set by a call to
setDestination(ImageTypeSpecifier), as an
ImageTypeSpecifier. If none was set,
null is returned.
Returns: an ImageTypeSpecifier describing the destination type, or null.
See Also: IIOParam.setDestinationType(javax.imageio.ImageTypeSpecifier),

  Returns the currently set Locale, or null if only a default Locale is supported.

  Returns the currently set Locale, or
null if only a default Locale is
supported.
Returns: the current Locale, or null.

  Returns a localized version of the name of the current compression type, using the Locale returned by getLocale.

  Returns a localized version of the name of the current compression type, using the Locale returned by getLocale.

The default implementation checks whether compression is supported and the compression mode is MODE_EXPLICIT. If so, if compressionType is non-null the value of getCompressionType is returned as a convenience.
Returns: a String containing a localized version of the name of the current compression type.
Throws:
- UnsupportedOperationException - if the writer does not support compression.
- IllegalStateException - if the compression mode is not MODE_EXPLICIT.
- IllegalStateException - if no compression type is set.

  Returns an array of Dimensions indicating the legal size ranges for tiles as they will be encoded in the output file or stream.

  Returns an array of Dimensions indicating the legal size ranges for tiles as they will be encoded in the output file or stream. The returned array is a copy.

The information is returned as a set of pairs; the first element of a pair contains an (inclusive) minimum width and height, and the second element contains an (inclusive) maximum width and height. Together, each pair defines a valid range of sizes. To specify a fixed size, use the same width and height for both elements. To specify an arbitrary range, a value of null is used in place of an actual array of Dimensions.

If no array is specified on the constructor, but tiling is allowed, then this method returns null.
Returns: an array of Dimensions with an even length of at least two, or null.
Throws:
- UnsupportedOperationException - if the plug-in does not support tiling.

  Returns the current mode for writing the stream in a progressive manner.

  Returns the current mode for writing the stream in a
progressive manner.
Returns: the current mode for progressive encoding.
Throws:
- UnsupportedOperationException - if the writer does not support progressive encoding.
See Also: ImageWriteParam.setProgressiveMode(int),

  Returns the set of of source bands to be used.

  Returns the set of of source bands to be used. The returned value is that set by the most recent call to setSourceBands, or null if there have been no calls to setSourceBands.

Semantically, the array returned is a copy; changes to array contents subsequent to this call have no effect on this IIOParam.
Returns: the set of source bands to be used, or null.
See Also: IIOParam.setSourceBands(int[]),

  Returns the source region to be used.

  Returns the source region to be used. The returned value is
that set by the most recent call to
setSourceRegion, and will be null if
there is no region set.
Returns: the source region of interest as a Rectangle, or null.
See Also: IIOParam.setSourceRegion(java.awt.Rectangle),

  Returns the number of source columns to advance for each pixel.

  Returns the number of source columns to advance for each pixel.

If setSourceSubsampling has not been called, 1 is returned (which is the correct value).
Returns: the source subsampling X period.
See Also: IIOParam.setSourceSubsampling(int, int, int, int), IIOParam.getSourceYSubsampling(),

  Returns the number of rows to advance for each pixel.

  Returns the number of rows to advance for each pixel.

If setSourceSubsampling has not been called, 1 is returned (which is the correct value).
Returns: the source subsampling Y period.
See Also: IIOParam.setSourceSubsampling(int, int, int, int), IIOParam.getSourceXSubsampling(),

  Returns the horizontal offset of the subsampling grid.

  Returns the horizontal offset of the subsampling grid.

If setSourceSubsampling has not been called, 0 is returned (which is the correct value).
Returns: the source subsampling grid X offset.
See Also: IIOParam.setSourceSubsampling(int, int, int, int), IIOParam.getSubsamplingYOffset(),

  Returns the vertical offset of the subsampling grid.

  Returns the vertical offset of the subsampling grid.

If setSourceSubsampling has not been called, 0 is returned (which is the correct value).
Returns: the source subsampling grid Y offset.
See Also: IIOParam.setSourceSubsampling(int, int, int, int), IIOParam.getSubsamplingXOffset(),

  Returns the horizontal tile grid offset of an image as it will be written to the output stream.

  Returns the horizontal tile grid offset of an image as it will
be written to the output stream. If tiling parameters have not
been set, an IllegalStateException is thrown.
Returns: the tile grid X offset to be used for encoding.
Throws:
- UnsupportedOperationException - if the plug-in does not support tiling.
- IllegalStateException - if the tiling mode is not MODE_EXPLICIT.
- IllegalStateException - if the tiling parameters have not been set.
See Also: ImageWriteParam.setTiling(int, int, int, int), ImageWriteParam.getTileGridYOffset(),

  Returns the vertical tile grid offset of an image as it will be written to the output stream.

  Returns the vertical tile grid offset of an image as it will
be written to the output stream. If tiling parameters have not
been set, an IllegalStateException is thrown.
Returns: the tile grid Y offset to be used for encoding.
Throws:
- UnsupportedOperationException - if the plug-in does not support tiling.
- IllegalStateException - if the tiling mode is not MODE_EXPLICIT.
- IllegalStateException - if the tiling parameters have not been set.
See Also: ImageWriteParam.setTiling(int, int, int, int), ImageWriteParam.getTileGridXOffset(),

  Returns the height of each tile in an image as it will be written to the output stream.

  Returns the height of each tile in an image as it will be written to
the output stream. If tiling parameters have not
been set, an IllegalStateException is thrown.
Returns: the tile height to be used for encoding.
Throws:
- UnsupportedOperationException - if the plug-in does not support tiling.
- IllegalStateException - if the tiling mode is not MODE_EXPLICIT.
- IllegalStateException - if the tiling parameters have not been set.
See Also: ImageWriteParam.setTiling(int, int, int, int), ImageWriteParam.getTileWidth(),

  Returns the width of each tile in an image as it will be written to the output stream.

  Returns the width of each tile in an image as it will be
written to the output stream. If tiling parameters have not
been set, an IllegalStateException is thrown.
Returns: the tile width to be used for encoding.
Throws:
- UnsupportedOperationException - if the plug-in does not support tiling.
- IllegalStateException - if the tiling mode is not MODE_EXPLICIT.
- IllegalStateException - if the tiling parameters have not been set.
See Also: ImageWriteParam.setTiling(int, int, int, int), ImageWriteParam.getTileHeight(),

  Returns the current tiling mode, if tiling is supported.

  Returns the current tiling mode, if tiling is supported.
Otherwise throws an UnsupportedOperationException.
Returns: the current tiling mode.
Throws:
- UnsupportedOperationException - if canWriteTiles returns false.
See Also: ImageWriteParam.setTilingMode(int),

  Returns true if there is a controller installed for this IIOParam object.

  Returns true if there is a controller installed
for this IIOParam object. This will return
true if getController would not
return null.
Returns: true if a controller is installed.
See Also: IIOParamController, IIOParam.setController(IIOParamController), IIOParam.getController(), IIOParam.getDefaultController(), IIOParam.activateController(),

  Returns true if the current compression type provides lossless compression.

  Returns true if the current compression type provides lossless compression. If a plug-in provides only one mandatory compression type, then this method may be called without calling setCompressionType first.

If there are multiple compression types but none has been set, an IllegalStateException is thrown.

The default implementation checks whether compression is supported and the compression mode is MODE_EXPLICIT. If so, if getCompressionTypes() is null or getCompressionType() is non-null true is returned as a convenience.
Returns: true if the current compression type is lossless.
Throws:
- UnsupportedOperationException - if the writer does not support compression.
- IllegalStateException - if the compression mode is not MODE_EXPLICIT.
- IllegalStateException - if the set of legal compression types is non-null and the current compression type is null.

  Specifies whether compression is to be performed, and if so how compression parameters are to be determined.

  Specifies whether compression is to be performed, and if so how compression parameters are to be determined. The mode argument must be one of the four modes, interpreted as follows:

• MODE_DISABLED - If the mode is set to MODE_DISABLED, methods that query or modify the compression type or parameters will throw an IllegalStateException (if compression is normally supported by the plug-in). Some writers, such as JPEG, do not normally offer uncompressed output. In this case, attempting to set the mode to MODE_DISABLED will throw an UnsupportedOperationException and the mode will not be changed.
• MODE_EXPLICIT - Compress using the compression type and quality settings specified in this ImageWriteParam. Any previously set compression parameters are discarded.
• MODE_COPY_FROM_METADATA - Use whatever compression parameters are specified in metadata objects passed in to the writer.
• MODE_DEFAULT - Use default compression parameters.

The default is MODE_COPY_FROM_METADATA.
Parameters:
- mode - The mode for setting compression in the output stream.
Throws:
- UnsupportedOperationException - if the writer does not support compression, or does not support the requested mode.
- IllegalArgumentException - if mode is not one of the modes listed above.
See Also: ImageWriteParam.getCompressionMode(),

  Sets the compression quality to a value between 0 and 1.

  Sets the compression quality to a value between 0 and 1. Only a single compression quality setting is supported by default; writers can provide extended versions of ImageWriteParam that offer more control. For lossy compression schemes, the compression quality should control the tradeoff between file size and image quality (for example, by choosing quantization tables when writing JPEG images). For lossless schemes, the compression quality may be used to control the tradeoff between file size and time taken to perform the compression (for example, by optimizing row filters and setting the ZLIB compression level when writing PNG images).

A compression quality setting of 0.0 is most generically interpreted as "high compression is important," while a setting of 1.0 is most generically interpreted as "high image quality is important."

If there are multiple compression types but none has been set, an IllegalStateException is thrown.

The default implementation checks that compression is supported, and that the compression mode is MODE_EXPLICIT. If so, if getCompressionTypes() returns null or compressionType is non-null it sets the compressionQuality instance variable.
Parameters:
- quality - a float between 0and 1 indicating the desired quality level.
Throws:
- UnsupportedOperationException - if the writer does not support compression.
- IllegalStateException - if the compression mode is not MODE_EXPLICIT.
- IllegalStateException - if the set of legal compression types is non-null and the current compression type is null.
- IllegalArgumentException - if quality is not between 0and 1, inclusive.
See Also: ImageWriteParam.getCompressionQuality(),

  Sets the compression type to one of the values indicated by getCompressionTypes.

  Sets the compression type to one of the values indicated by getCompressionTypes. If a value of null is passed in, any previous setting is removed.

The default implementation checks whether compression is supported and the compression mode is MODE_EXPLICIT. If so, it calls getCompressionTypes and checks if compressionType is one of the legal values. If it is, the compressionType instance variable is set. If compressionType is null, the instance variable is set without performing any checking.
Parameters:
- compressionType - one of the Strings returned by getCompressionTypes, or null to remove any previous setting.
Throws:
- UnsupportedOperationException - if the writer does not support compression.
- IllegalStateException - if the compression mode is not MODE_EXPLICIT.
- UnsupportedOperationException - if there are no settable compression types.
- IllegalArgumentException - if compressionType is non-null but is not one of the values returned by getCompressionTypes.
See Also: ImageWriteParam.getCompressionTypes(), ImageWriteParam.getCompressionType(), ImageWriteParam.unsetCompression(),

  Sets the IIOParamController to be used to provide settings for this IIOParam object when the activateController method is called, overriding any default controller.

  Sets the IIOParamController to be used
to provide settings for this IIOParam
object when the activateController method
is called, overriding any default controller. If the
argument is null, no controller will be
used, including any default. To restore the default, use
setController(getDefaultController()).
Parameters:
- controller - An appropriate IIOParamController, or null.
See Also: IIOParamController, IIOParam.getController(), IIOParam.getDefaultController(), IIOParam.hasController(), IIOParam.activateController(),

  Specifies the offset in the destination image at which future decoded pixels are to be placed, when reading, or where a region will be written, when writing.

  Specifies the offset in the destination image at which future decoded pixels are to be placed, when reading, or where a region will be written, when writing.

When reading, the region to be written within the destination BufferedImage will start at this offset and have a width and height determined by the source region of interest, the subsampling parameters, and the destination bounds.

Normal writes are not affected by this method, only writes performed using ImageWriter.replacePixels. For such writes, the offset specified is within the output stream image whose pixels are being modified.

There is no unsetDestinationOffset method; simply call setDestinationOffset(new Point(0, 0)) to restore default values.
Parameters:
- destinationOffset - the offset in the destination, as a Point.
Throws:
- IllegalArgumentException - if destinationOffset is null.
See Also: IIOParam.getDestinationOffset(), ImageWriter.replacePixels(java.awt.image.RenderedImage, javax.imageio.ImageWriteParam),

  Sets the desired image type for the destination image, using an ImageTypeSpecifier.

  Sets the desired image type for the destination image, using an ImageTypeSpecifier.

When reading, if the layout of the destination has been set using this method, each call to an ImageReader read method will return a new BufferedImage using the format specified by the supplied type specifier. As a side effect, any destination BufferedImage set by ImageReadParam.setDestination(BufferedImage) will no longer be set as the destination. In other words, this method may be thought of as calling setDestination((BufferedImage)null).

When writing, the destination type maybe used to determine the color type of the image. The SampleModel information will be ignored, and may be null. For example, a 4-banded image could represent either CMYK or RGBA data. If a destination type is set, its ColorModel will override any ColorModel on the image itself. This is crucial when setSourceBands is used since the image's ColorModel will refer to the entire image rather than to the subset of bands being written.
Parameters:
- destinationType - the ImageTypeSpecifier to be used to determine the destination layout and color type.
See Also: IIOParam.getDestinationType(),

  Specifies that the writer is to write the image out in a progressive mode such that the stream will contain a series of scans of increasing quality.

  Specifies that the writer is to write the image out in a progressive mode such that the stream will contain a series of scans of increasing quality. If progressive encoding is not supported, an UnsupportedOperationException will be thrown.

The mode argument determines how the progression parameters are chosen, and must be either MODE_DISABLED, MODE_COPY_FROM_METADATA, or MODE_DEFAULT. Otherwise an IllegalArgumentException is thrown.

The modes are interpreted as follows:

• MODE_DISABLED - No progression. Use this to turn off progession.
• MODE_COPY_FROM_METADATA - The output image will use whatever progression parameters are found in the metadata objects passed into the writer.
• MODE_DEFAULT - The image will be written progressively, with parameters chosen by the writer.

The default is MODE_COPY_FROM_METADATA.
Parameters:
- mode - The mode for setting progression in the output stream.
Throws:
- UnsupportedOperationException - if the writer does not support progressive encoding.
- IllegalArgumentException - if mode is not one of the modes listed above.
See Also: ImageWriteParam.getProgressiveMode(),

  Sets the indices of the source bands to be used.

  Sets the indices of the source bands to be used. Duplicate indices are not allowed.

A null value indicates that all source bands will be used.

At the time of reading, an IllegalArgumentException will be thrown by the reader or writer if a value larger than the largest available source band index has been specified or if the number of source bands and destination bands to be used differ. The ImageReader.checkReadParamBandSettings method may be used to automate this test.

Semantically, a copy is made of the array; changes to the array contents subsequent to this call have no effect on this IIOParam.
Parameters:
- sourceBands - an array of integer band indices to be used.
Throws:
- IllegalArgumentException - if sourceBands contains a negative or duplicate value.
See Also: IIOParam.getSourceBands(), ImageReadParam.setDestinationBands(int[]), ImageReader.checkReadParamBandSettings(javax.imageio.ImageReadParam, int, int),

  Sets the source region of interest.

  Sets the source region of interest. The region of interest is described as a rectangle, with the upper-left corner of the source image as pixel (0, 0) and increasing values down and to the right. The actual number of pixels used will depend on the subsampling factors set by setSourceSubsampling. If subsampling has been set such that this number is zero, an IllegalStateException will be thrown.

The source region of interest specified by this method will be clipped as needed to fit within the source bounds, as well as the destination offsets, width, and height at the time of actual I/O.

A value of null for sourceRegion will remove any region specification, causing the entire image to be used.
Parameters:
- sourceRegion - a Rectangle specifying the source region of interest, or null.
Throws:
- IllegalArgumentException - if sourceRegion is non-null and either sourceRegion.x or sourceRegion.y is negative.
- IllegalArgumentException - if sourceRegion is non-null and either sourceRegion.width or sourceRegion.height is negative or 0.
- IllegalStateException - if subsampling is such that this region will have a subsampled width or height of zero.
See Also: IIOParam.getSourceRegion(), IIOParam.setSourceSubsampling(int, int, int, int), IIOParam.setDestinationOffset(java.awt.Point), IIOParam.getDestinationOffset(),

  Specifies a decimation subsampling to apply on I/O.

  Specifies a decimation subsampling to apply on I/O. The sourceXSubsampling and sourceYSubsampling parameters specify the subsampling period (i.e., the number of rows and columns to advance after every source pixel). Specifically, a period of 1 will use every row or column; a period of 2 will use every other row or column. The subsamplingXOffset and subsamplingYOffset parameters specify an offset from the region (or image) origin for the first subsampled pixel. Adjusting the origin of the subsample grid is useful for avoiding seams when subsampling a very large source image into destination regions that will be assembled into a complete subsampled image. Most users will want to simply leave these parameters at 0.

The number of pixels and scanlines to be used are calculated as follows.

The number of subsampled pixels in a scanline is given by

truncate[(width - subsamplingXOffset + sourceXSubsampling - 1) / sourceXSubsampling].

If the region is such that this width is zero, an IllegalStateException is thrown.

The number of scanlines to be used can be computed similarly.

The ability to set the subsampling grid to start somewhere other than the source region origin is useful if the region is being used to create subsampled tiles of a large image, where the tile width and height are not multiples of the subsampling periods. If the subsampling grid does not remain consistent from tile to tile, there will be artifacts at the tile boundaries. By adjusting the subsampling grid offset for each tile to compensate, these artifacts can be avoided. The tradeoff is that in order to avoid these artifacts, the tiles are not all the same size. The grid offset to use in this case is given by:
grid offset = [period - (region offset modulo period)] modulo period)

If either sourceXSubsampling or sourceYSubsampling is 0 or negative, an IllegalArgumentException will be thrown.

If either subsamplingXOffset or subsamplingYOffset is negative or greater than or equal to the corresponding period, an IllegalArgumentException will be thrown.

There is no unsetSourceSubsampling method; simply call setSourceSubsampling(1, 1, 0, 0) to restore default values.
Parameters:
- sourceXSubsampling - the number of columns to advance between pixels.
- sourceYSubsampling - the number of rows to advance between pixels.
- subsamplingXOffset - the horizontal offset of the first subsample within the region, or within the image if no region is set.
- subsamplingYOffset - the horizontal offset of the first subsample within the region, or within the image if no region is set.
Throws:
- IllegalArgumentException - if either period is negative or 0, or if either grid offset is negative or greater than the corresponding period.
- IllegalStateException - if the source region is such that the subsampled output would contain no pixels.

  Specifies that the image should be tiled in the output stream.

  Specifies that the image should be tiled in the output stream. The tileWidth and tileHeight parameters specify the width and height of the tiles in the file. If the tile width or height is greater than the width or height of the image, the image is not tiled in that dimension.

If canOffsetTiles returns false, then the tileGridXOffset and tileGridYOffset parameters must be zero.
Parameters:
- tileWidth - the width of each tile.
- tileHeight - the height of each tile.
- tileGridXOffset - the horizontal offset of the tile grid.
- tileGridYOffset - the vertical offset of the tile grid.
Throws:
- UnsupportedOperationException - if the plug-in does not support tiling.
- IllegalStateException - if the tiling mode is not MODE_EXPLICIT.
- UnsupportedOperationException - if the plug-in does not support grid offsets, and the grid offsets are not both zero.
- IllegalArgumentException - if the tile size is not within one of the allowable ranges returned by getPreferredTileSizes.
- IllegalArgumentException - if tileWidth or tileHeight is less than or equal to 0.
See Also: ImageWriteParam.canWriteTiles, ImageWriteParam.canOffsetTiles, ImageWriteParam.getTileWidth(), ImageWriteParam.getTileHeight(), ImageWriteParam.getTileGridXOffset(), ImageWriteParam.getTileGridYOffset(),

  Determines whether the image will be tiled in the output stream and, if it will, how the tiling parameters will be determined.

  Determines whether the image will be tiled in the output
stream and, if it will, how the tiling parameters will be
determined. The modes are interpreted as follows:

• MODE_DISABLED - The image will not be tiled.
  setTiling will throw an
  IllegalStateException.
  
  
• MODE_DEFAULT - The image will be tiled using
  default parameters. setTiling will throw an
  IllegalStateException.
  
  
• MODE_EXPLICIT - The image will be tiled
  according to parameters given in the setTiling method. Any previously set tiling
  parameters are discarded.
  
  
• MODE_COPY_FROM_METADATA - The image will
  conform to the metadata object passed in to a write.
  setTiling will throw an
  IllegalStateException.
  
  

Parameters:
- mode - The mode to use for tiling.
Throws:
- UnsupportedOperationException - if canWriteTiles returns false.
- IllegalArgumentException - if mode is not one of the modes listed above.
See Also: ImageWriteParam.setTiling(int, int, int, int), ImageWriteParam.getTilingMode(),

  Removes any previous compression type and quality settings.

  Removes any previous compression type and quality settings.

The default implementation sets the instance variable compressionType to null, and the instance variable compressionQuality to 1.0F.
Throws:
- UnsupportedOperationException - if the plug-in does not support compression.
- IllegalStateException - if the compression mode is not MODE_EXPLICIT.
See Also: ImageWriteParam.setCompressionType(java.lang.String), ImageWriteParam.setCompressionQuality(float),

  Removes any previous tile grid parameters specified by calls to setTiling.

  Removes any previous tile grid parameters specified by calls to setTiling.

The default implementation sets the instance variables tileWidth, tileHeight, tileGridXOffset, and tileGridYOffset to 0.
Throws:
- UnsupportedOperationException - if the plug-in does not support tiling.
- IllegalStateException - if the tiling mode is not MODE_EXPLICIT.
See Also: ImageWriteParam.setTiling(int, int, int, int),