[gdal-dev] GDAL Tiling

[Even Rouault]

Selon akshay gupta <akshaygupta202 at gmail.com>:

> I am presently using -srcwin for copying AOI to a different file. does
> -projwin have any advantage over -srcwin?

No, the underlying processing is the same. You just use what option is the more
convenient for you. In fact, when -projwin is used, the projected/geographic
coordinates are transformed into pixel coordinates.

>
> Akhy
>
> On Wed, Mar 28, 2012 at 5:29 PM, Jay L. <jzl5325 at psu.edu> wrote:
>
> > Akshay,
> >
> > 1) An AOI can be created using the -projwin option in gdal_translate.  You
> > can use that option when creating a new raster with a new tiles size.
> >
> > 2) Using the Python bindings it is possible to read a segment of a raster
> > into memory without allocating memory.  I am unsure using another other
> > language.
> >
> > Jay
> >
> >
> > On Wed, Mar 28, 2012 at 5:16 AM, Mateusz Loskot <mateusz at loskot.net>wrote:
> >
> >> On 28 March 2012 07:45, akshay gupta <akshaygupta202 at gmail.com> wrote:
> >> > 2) When I read an image through ReadBlock() i had to allocate some
> >> memory
> >> > and pass it in the function. Is there some way that i get the image data
> >> > stored in GDALRasterBlock directly without passing my own allocated
> >> memory.
> >>
> >> http://www.gdal.org/classGDALRasterBlock.html#_details
> >>
> >> "In normal situations applications do not interact directly
> >> with the GDALRasterBlock - instead it it utilized
> >> by the RasterIO() interfaces to implement caching"
> >>
> >> Best regards,
> >> --
> >> Mateusz Loskot, http://mateusz.loskot.net
> >>
> >
> >
>