Hello Martin and all , Thank for your help . The present I haved 3 tag ModelPixelScaleTag, ModelTiepointTag, ModelTransformationTag and I haved wide image and height image too , So What would I do next ?
Hao On Thu, Aug 4, 2016 at 2:42 PM, Martin Desruisseaux < [email protected]> wrote: > Hello Hao > > I'm moving a question on the public list since I believe that some other > peoples know better than me. > > About how to get the geographic bounding box from a GeoTIFF file: I > didn't saw tags specifically for this purpose in GeoTIFF, but this can > be computed indirectly. First we need to build the mathematical function > that convert pixel coordinates to geographic or projected coordinates. > Then we can use that function for converting the raster bounds (in pixel > coordinates) to geographic or projected envelope. > > For creating the mathematical function as an "affine transform", we need > one of the following tags [1]: > > * ModelPixelScaleTag > * ModelTiepointTag > > or > > * ModelTransformationTag > > What are the tags that you have in your GeoTIFF file? For starting, we > would focus on what you have. > > Martin > > > [1] http://www.remotesensing.org/geotiff/spec/geotiff2.7.html#2.7 > >
