An interface describing objects that transform an InputStream
into a Raster.
This interface is designed to allow decoding of formats that
include information about the format of the encoded tile as well as ones
that don't. In order to create a Raster, at the very least,
a Point specifying the top left corner of the
Raster, a SampleModel specifying the data layout
and a DataBuffer with the decoded pixel data are
needed. The DataBuffer can be created from the
information from the SampleModel and the decoded data.
Therefore the absolute minimum information that is required in order to
create a Raster on decoding (aside from the decoded data
itself) is a Point specifying the top left corner of the
Raster and a SampleModel specifying the data
layout. The formats that do include this information should return true
from the includesSampleModelInfo() and
includesLocationInfo() from the associated
TileCodecDescriptor if they include information needed to
create a SampleModel and information needed to
create the Point respectively. The formats that do not
include this information in the encoded stream should return false. The
TileCodecParameterList providing the decoding parameters
will in this case be expected to contain a parameter named "sampleModel"
with a non-null SampleModel as its value. This
SampleModel will be used to create the decoded
Raster.
The formats that return true from includesSampleModelInfo()
should use the decode() method to cause the decoding to take
place, the ones that return false should specify the Point
location to the decoding process by using the decode(Point)
method. Similarly the SampleModel must be specified as a
parameter with a non-null value on the TileCodecParameterList
passed to this TileDecoder if
includesSampleModelInfo() returns false. It is expected that
the SampleModel specified in the parameter list is the
SampleModel of the encoded tiles, in order to get a
decoded Raster that is equivalent to the one encoded. If the
SampleModel specified through the parameter list is different
from those of the encoded tiles, the result of decoding is undefined.
If includesSampleModelInfo() returns true, the
SampleModel (if present) on the
TileCodecParameterList is ignored.
See Also: TileCodecDescriptor
See Also: TileEncoder
since:
JAI 1.1 |