"Traditionally GDAL has treated this flag as having no relevance to the georeferencing of the image despite disputes from a variety of other software developers and data producers. This was based on the authors interpretation of something said once by the GeoTIFF author. However, a recent review of section [section 2.5.2.2] of the GeoTIFF specificaiton has made it clear that GDAL behavior is incorrect and that PixelIsPoint georeferencing needs to be offset by a half a pixel when transformed to the GDAL georeferencing model."
For instance, in GDAL there's a whole RFC for dealing with issues related to pixel corners versus pixel centers!
https://gdal.org/development/rfc/rfc33_gtiff_pixelispoint.ht...
"Traditionally GDAL has treated this flag as having no relevance to the georeferencing of the image despite disputes from a variety of other software developers and data producers. This was based on the authors interpretation of something said once by the GeoTIFF author. However, a recent review of section [section 2.5.2.2] of the GeoTIFF specificaiton has made it clear that GDAL behavior is incorrect and that PixelIsPoint georeferencing needs to be offset by a half a pixel when transformed to the GDAL georeferencing model."