Find Lat/long Coordinates From Pixel Point In .geotiff Using Python And Gdal

I have points defined by pixel coordinates in a .geotiff imagesat. I am trying to convert these pixel coordinates into longitude and latitude. At first a tried to adapt the given

Solution 1:

You have flipped the order in which you convert between pixels, projected coordinates and lat longs. You are doing the order pixels -> lat lngs -> projected it should be pixels -> projected -> lat lngs.

The following should work

from osgeo import osr, ogr, gdal


def pixel_to_world(geo_matrix, x, y):
    ul_x = geo_matrix[0]
    ul_y = geo_matrix[3]
    x_dist = geo_matrix[1]
    y_dist = geo_matrix[5]
    _x = x * x_dist + ul_x
    _y = y * y_dist + ul_y
    return _x, _y


def build_transform_inverse(dataset, EPSG):
    source = osr.SpatialReference(wkt=dataset.GetProjection())
    target = osr.SpatialReference()
    target.ImportFromEPSG(EPSG)
    return osr.CoordinateTransformation(source, target)


def find_spatial_coordinate_from_pixel(dataset, transform, x, y):
    world_x, world_y = pixel_to_world(dataset.GetGeoTransform(), x, y)
    point = ogr.Geometry(ogr.wkbPoint)
    point.AddPoint(world_x, world_y)
    point.Transform(transform)
    return point.GetX(), point.GetY()

ds = gdal.Open(source_directory_path + filename)
_t = build_transform_inverse(ds, 4326)
coordinates = find_spatial_coordinate_from_pixel(ds, _t, point[0], point[1])
print(coordinates)

In find_spatial_coordinate_from_pixel i have flipped the order, such that pixel_to_world is now called first, before the coordinate transformation.