I am new in programming with maps and coordinates, I am making a software on python where I load a raster (in UTM 18S that extent up to 19S, south orientation ) and a Landsat8 (orientation north), if the Landsat image is on UTM 18S and inside the raster limits; between PATH 5-9 and ROW 60-68; I can overlap both image and have a good coordinate alignment
The problem appears when I try to use a landsat that is on UTM 19S, I reproject it with
pyproj library and the projections from the metadata, checked on QGIS and the coordinates are correct:
p1 = Proj(proj='utm', zone=19,datum='WGS84') p2 = Proj(proj="utm", zone=18,datum='WGS84') UL_X_PRODUCT = 122700.000 UL_Y_PRODUCT = -204000.000 UR_X_PRODUCT = 350400.000 UR_Y_PRODUCT = -204000.000 LL_X_PRODUCT = 122700.000 LL_Y_PRODUCT = -436500.000 LR_X_PRODUCT = 350400.000 LR_Y_PRODUCT = -436500.000 a1,b1=transform(p1, p2, UL_X_PRODUCT, UL_Y_PRODUCT) a2,b2=transform(p1, p2, UR_X_PRODUCT, UR_Y_PRODUCT) a3,b3=transform(p1, p2, LL_X_PRODUCT, LL_Y_PRODUCT) a4,b4=transform(p1, p2, LR_X_PRODUCT, LR_Y_PRODUCT)
result (added 10 million to be oriented in south orientation):
UL X, Y, (1e7+Y): 790329.086988 -203853.453007 9796146.54699 UR X, Y, (1e7+Y): 1018292.89036 -204622.506814 9795377.49319 LL X, Y, (1e7+Y): 789100.325377 -436182.202764 9563817.79724 LR X, Y, (1e7+Y): 1017056.67578 -437826.672301 9562173.3277
Is there any other good library to reproject UTM zones? Could the misalligment be due to reprojection error correction? I understand that a coordinate that is near the limit, can be different from 18S and 19S.