ComponentSampleModel
format and binary image data in a zero-offset byte array format even when the original data are not so stored. RasterAccessor
is meant to make the common (ComponentSampleModel
) case fast and other formats possible without forcing the OpImage
writer to cover more than one case per non-binary data type. When constructing a RasterAccessor
with a source(s) that has an IndexColorModel and a destination that has a non-IndexColorModel
, RasterAccessor
will perform expansion of the source pixels. If the source(s) and the destination have an IndexColorModel, then RasterAccessor
will assume that the operation can correctly process an IndexColorModel source and will not expand the source pixels (colormap indices) into color components. Refer to {@link JAI#KEY_REPLACE_INDEX_COLOR_MODEL} for a mechanism by which the destination image's ColorModel
is set to a non-IndexColorModel
to cause RasterAccessor
to expand the source's IndexColorModel
.
Binary data are handled as a special case. In general image data are considered to be binary when the image has a single-banded MultiPixelPackedSampleModel
with one bit per pixel. This may be verified by invoking the isBinary()
method. For this case the methods getBinaryDataArray()
and copyBinaryDataToRaster()
should be used to access and set, respectively, the binary data in packed form. If the binary data are to be accessed in expanded form, i.e., as bytes, then the usual byte methods getByteDataArray()
, getByteDataArrays()
, and copyDataToRaster()
should be used.
ComponentSampleModel
format and binary image data in a zero-offset byte array format even when the original data are not so stored. RasterAccessor
is meant to make the common (ComponentSampleModel
) case fast and other formats possible without forcing the OpImage
writer to cover more than one case per non-binary data type. When constructing a RasterAccessor
with a source(s) that has an IndexColorModel and a destination that has a non-IndexColorModel
, RasterAccessor
will perform expansion of the source pixels. If the source(s) and the destination have an IndexColorModel, then RasterAccessor
will assume that the operation can correctly process an IndexColorModel source and will not expand the source pixels (colormap indices) into color components. Refer to {@link JAI#KEY_REPLACE_INDEX_COLOR_MODEL} for a mechanism by which the destination image's ColorModel
is set to a non-IndexColorModel
to cause RasterAccessor
to expand the source's IndexColorModel
.
Binary data are handled as a special case. In general image data are considered to be binary when the image has a single-banded MultiPixelPackedSampleModel
with one bit per pixel. This may be verified by invoking the isBinary()
method. For this case the methods getBinaryDataArray()
and copyBinaryDataToRaster()
should be used to access and set, respectively, the binary data in packed form. If the binary data are to be accessed in expanded form, i.e., as bytes, then the usual byte methods getByteDataArray()
, getByteDataArrays()
, and copyDataToRaster()
should be used.
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