gdal_translate: XYZ driver flips image vertically

[hkohr]

Using the XYZ driver directly and a detour via CSV import and interpolation produces different results: the XYZ flips the image vertically.

Steps to reproduce:

With XYZ driver

Statistics:

kohr@iam-ma-023 ~/dgm_test $ gdalinfo -stats -nomd test.xyz
Driver: XYZ/ASCII Gridded XYZ
Files: test.xyz
Size is 501, 501
Coordinate System is `'
Origin = (2585299.500000000000000,5457199.500000000000000)
Pixel Size = (1.000000000000000,1.000000000000000)
Corner Coordinates:
Upper Left  ( 2585299.500, 5457199.500) 
Lower Left  ( 2585299.500, 5457700.500) 
Upper Right ( 2585800.500, 5457199.500) 
Lower Right ( 2585800.500, 5457700.500) 
Center      ( 2585550.000, 5457450.000) 
Band 1 Block=501x1 Type=Float32, ColorInterp=Undefined
  Minimum=235.211, Maximum=355.767, Mean=286.486, StdDev=37.135

Translation to GeoTiff:

kohr@iam-ma-023 ~/dgm_test $ gdal_translate -of GTiff -ot byte -scale 235 356 test.xyz test_xyz.tiff

With gridded data

Using QGis -> CSV import -> interpolation -> output:test.tin

Statistics:

kohr@iam-ma-023 ~/dgm_test $ gdalinfo -stats -nomd test.tin 
Driver: AAIGrid/Arc/Info ASCII Grid
Files: test.tin
Size is 500, 500
Coordinate System is `'
Origin = (2585300.000000000000000,5457700.000000000000000)
Pixel Size = (1.000000000000000,-1.000000000000000)
Corner Coordinates:
Upper Left  ( 2585300.000, 5457700.000) 
Lower Left  ( 2585300.000, 5457200.000) 
Upper Right ( 2585800.000, 5457700.000) 
Lower Right ( 2585800.000, 5457200.000) 
Center      ( 2585550.000, 5457450.000) 
Band 1 Block=500x1 Type=Float32, ColorInterp=Undefined
  Minimum=235.260, Maximum=355.607, Mean=286.440, StdDev=37.055
  NoData Value=-9999

Translation to GeoTiff:

kohr@iam-ma-023 ~/dgm_test $ gdal_translate -of GTiff -ot byte -scale 235 356 test.tin test_tin.tiff

[hkohr]

Hillshading image from the original dataset