public interface ProductReader
ProductReader
interface know how to create an in-memory representation of a
given data product as input source.ProductWriter
Modifier and Type | Method and Description |
---|---|
void |
close()
Closes the access to all currently opened resources such as file input streams and all resources of this children
directly owned by this reader.
|
Object |
getInput()
Retrives the current input destination object.
|
ProductReaderPlugIn |
getReaderPlugIn()
Returns the plug-in which created this product reader.
|
ProductSubsetDef |
getSubsetDef()
Returns the subset information with which this a data product is read from its physical source.
|
void |
readBandRasterData(Band destBand,
int destOffsetX,
int destOffsetY,
int destWidth,
int destHeight,
ProductData destBuffer,
ProgressMonitor pm)
Reads raster data from the data source specified by the given destination band into the given in-memory buffer
and region.
|
Product |
readProductNodes(Object input,
ProductSubsetDef subsetDef)
Reads a data product and returns a in-memory representation of it.
|
ProductReaderPlugIn getReaderPlugIn()
null
Object getInput()
null
if the
setInput
has not been called so far.ProductSubsetDef getSubsetDef()
null
Product readProductNodes(Object input, ProductSubsetDef subsetDef) throws IOException, IllegalFileFormatException
The given subset info can be used to specify spatial and spectral portions of the original proudct. If the subset is omitted, the complete product is read in.
Whether the band data - the actual pixel values - is read in immediately or later when pixels are requested, is up to the implementation.
input
- an object representing a valid output for this product reader, might be a
ImageInputStream
or other Object
to use for future decoding.subsetDef
- a spectral or spatial subset (or both) of the product. If null
, the entire product
is read inIllegalArgumentException
- if input
is null
or it's type is not one of the
supported input sources.IOException
- if an I/O error occursIllegalFileFormatException
- if the file format is illegalvoid readBandRasterData(Band destBand, int destOffsetX, int destOffsetY, int destWidth, int destHeight, ProductData destBuffer, ProgressMonitor pm) throws IOException
ProductSubsetDef
instance attached to it, the method
should also consider the specified spatial subset and sub-sampling (if any) applied to the destination band.
destOffsetX
,
destOffsetY
, destWidth
and destHeight
parameters are given in the band's
raster co-ordinates of the raster which results after applying the optional spatial subset and
sub-sampling given by the ProductSubsetDef
instance to the data source. If no spatial subset
and sub-sampling is specified, the destination co-ordinates are identical with the source co-ordinates. The
destination region should always specify a sub-region of the band's scene raster.
destOffsetX
and destOffsetY
of the destination region. The offset parameters are
not an offset within the buffer.destWidth *
destHeight
. The pixel values read are stored in line-by-line order, so the raster X co-ordinate varies
faster than the Y co-ordinate.destBand
- the destination band which identifies the data source from which to read the sample valuesdestOffsetX
- the X-offset in the band's raster co-ordinatesdestOffsetY
- the Y-offset in the band's raster co-ordinatesdestWidth
- the width of region to be read given in the band's raster co-ordinatesdestHeight
- the height of region to be read given in the band's raster co-ordinatesdestBuffer
- the destination buffer which receives the sample values to be readIOException
- if an I/O error occursIllegalArgumentException
- if the number of elements destination buffer not equals destWidth *
destHeight
or the destination region is out of the band's scene rasterAbstractBand.getRasterWidth()
,
AbstractBand.getRasterHeight()
void close() throws IOException
This method should be called only if it is for sure that this object instance will never be used again. The
results of referencing an instance of this class after a call to close()
are undefined.
Overrides of this method should always call super.close();
after disposing this instance.
IOException
- if an I/O error occursCopyright © 2014–2015 European Space Agency (ESA). All rights reserved.