Sorry , I'm confused , I haven't ModelTransformationTag I just read ModelPixelScaleTag, ModelTiepointTag , width and height image
On Thu, Aug 4, 2016 at 2:53 PM, phuong hao nguyen thi < [email protected]> wrote: > 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 >> >> >
