Akhy,<br><br>1) Raster block size is a readonly property. The only way to change it is to create a new dataset with the new block size. For a tiff image you can use the creation options TILED, BLOCKXSIZE and BLOCKYSIZE [1].<br>
2) You can read the raster any way you want using the GDALRasterIO() and GDALDatasetRasterIO() functions. You can set the X and Y sizes.<br><br>[1]: <a href="http://www.gdal.org/frmt_gtiff.html">http://www.gdal.org/frmt_gtiff.html</a><br>
<br><div class="gmail_quote">On Tue, Mar 27, 2012 at 8:44 PM, akshay gupta <span dir="ltr"><<a href="mailto:akshaygupta202@gmail.com">akshaygupta202@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Hi,<br><br>I have few questions regarding GDAL tiling and overviews.<br><br>1) Is there any In build direct function in GDAL from where i can set the size of the tiles(raster block size).<br>2)I an facing an strange situation. I have an TIFF image, and I am trying to read it block by block using ReadBlock(). When i read block from the band of the original dataset(GDALDataset I get when i call GDALOpen() ), I get a tile which is of size Width X 1 but if i create overviews and then call ReadBlock() on the band extracted from the first overview i get square tiles(Blocks). Can any body tell me why is this happening, Is there any way of getting square tiles of same size irrespective of whether i call ReadBlock() on original Dataset or on the overview level.<br>
<br>Thanks and regards,<br>Akhy Hückelheim<br>
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