[gdal-dev] Question about raster interleaving

[Frank Warmerdam]

Jorge Arévalo wrote:
> Hi everybody,
> 
> If I'm implementing a driver for a given raster structure, that always
> has BSQ format, has sense to implement the IRasterIO for Dataset
> and/or Rasterband derived classes?

Jorge,

If the data is band interleaved there is little value in implementing
the GDALDataset::IRasterIO() method.  In theory you might be able to
provide an optimized override for GDALRasterBand::IRasterIO().  Are
you implementing your bands by deriving from RawRasterBand?  If so,
there is already an (in theory) optimized GDALRasterBand::IRasterIO()
override.

In any event, I find there are only rare circumstances where IRasterIO
overrides are worth the trouble of implmentation as opposed to providing
simple block oriented access.  So think about what your needs are and
remember that implementing IRasterIO() properly is relatively hard.

Best regards,
-- 
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