FSX Problem to create Blend Mask

I just tested it with Gimp, an uncompressed .tif works fine.
You are correct. However, using an uncompressed tiff, Resample took 3min 47 seconds. With the compressed tiff, it took 2min 1sec.

The compression ratios were exactly the same.
Interesting results, George ! :confused:

IMHO this raises questions as to what is different about the TIF file format output by GIMP in LZW compressed and uncompressed mode versus the TIF file format output by another graphics application such as Photoshop / Corel PhotoPaint or PaintShop Pro etc..

BTW: Could everyone tell us which version numbers of GIMP were used in this thread please ? :alert:

Alternatively, perhaps FS SDK Resample works different if INF file parameters "NullValue" or "Variation" are used ? :scratchch



NOTE: The OP has a "Variation" but no "NullValue" INF file parameter:


Regarding the "Variation" parameter, I assume FSX / P3D 1.x SDK Resample retro-compatibly honors substitution by the legacy FS2004 SDK Resample syntax of "BuildSeasons" ...in your own example INF posted above ?

Also, I assume FSX / P3D 1.x SDK Resample retro-compatibly honors substitution of ex:


...in "current" FSX SDK Resample INF parameter syntax, as shown at:


...by use of legacy syntax "Lat", "Lon" and "Cell" in your own example INF posted above, ex:


NumOfCellsPerLine = 15889 ;Pixel is not used in FSX
NumOfLines = 8447 ;Pixel is not used in FSX
Lon = 8.28059434890747 ;for top left and bottom right is: 8.33741784095764
Lat = 51.9372010231018 ;for top left and bottom right is: 51.914544403553
CellXdimensionDeg = 3.57627868652344E-06
CellYdimensionDeg = 2.68220901489258E-06

FYI: A previous discussion of TIF LZW compression versus performance with FS SDK Resample compilation:


PS: An interesting side note from reading the FS2004 SDK document "Custom Terrain Textures.Doc" which AFAIK was not included in the FSX SDK docs (perhaps ACES assumed GeoTIFFs would be used more often instead of BMPs ? :rolleyes:):

"Correcting Images that Contain Black Borders

Some of the images may contain a black border. This happens when the image source doesn’t fully cover a terrain cell. Each terrain cell falls on a multiple of 360/32768 degrees latitude, which is 0.010986328125 decimal degrees and 480/32768 degrees longitude, which is 0.0146484375 decimal degrees. To prevent this from happening, use the [Destination] directives NorthLat, SouthLat, EastLon, and WestLon to define the exact area to fall on a cell boundary within the source image."



NOTE: A discussion of options and linked threads related to dealing with this sub-topic of determining and specifying required and/or desired quad extents in a INF file for one's source imagery submitted to FS SDK Resample is here:



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You are correct. However, using an uncompressed tiff, Resample took 3min 47 seconds. With the compressed tiff, it took 2min 1sec.

The compression ratios were exactly the same.
Well the one I just did took 10 seconds without LZW compression and 17 seconds with. Pretty small source, maybe I should try a bigger one, lol. Also using identical CompressionQuality on both, the resulting .bgls are exactly the same size to the byte. Gimp 2.8
I was using Gimp 2.4.

The non-compressed tiff is 131MB and the compressed one 850MB. The bmp is 393MB and the final bgl (using either tiff) is 167MB, LOD 6 to 17.
Hi everybody,

first of all thank you very much for further support! I am using GIMP 2.8

Okay, I will do properly rework the tutorial this weekend to find out where to find the culprit...

But it can't "work fine" if you can't see the bgl in TmfViewer :confused:
Hmm, I think when the resample.exe is doing its work all parts inside the INF file are correct? My file sizes are around 143 MB background image and similar 140 MB blend mask with BMP and around 30 MB TIF. All tiles are being rendered inside the batch window and I got a ready bgl file to export for.

That suggests that you have both the masked and non-masked bgls in an active scenery area.
This sounds helpful and emphasizes my suggestion regarding my work in GIMP:

- The tutorial tells to delete my background layer after creating the blendmask. Afterwards, I have to export the remaining layer (blend mask) into the appropriated file (BMP or TIFF). Is this step correct?
- The tutorial doesn't tell anything about converting the blend mask into a greyscaled image or 8 bit format.
- Is working with layers needed basically? Or can I use a program instead of GIMP (e. g. Corel Paint) to simply produce an Alpha Mask to be set as blend mask?

Really strange because all steps except GIMP work immediately, without problems and satisfying.... I think I simply have some translation issues to understand the tutorials content :oops: ...
OK, which one?

Do you have Dropbox installed? If so, you could upload your bmp, tiff and inf files so that we could investigate further.
Hi George,

that's more than I could expect, thank you very much. Unbelievable, I installed Dropbox yesterday for a FS9 scenery sending. Much appreciate this offer...
Here's dropbox link, it includes background bmp, blend mask bmp and tif and also my inf file.


It's a shame, I don't want you guys to do my work, but I am looking very forward to solve the problem for better understanding the way to create sceneries in future. Thanks again.
Hi George,

unfortunately no improvement. TmFViewer still shows nothing and also just a square in FSX.... Any problem in the Background image possible? Or some wrong SBuilder tile import issue? But all parts seem to be correct so far until I started with GIMP...
That doesn't make sense.

This is what I see in TmfViewer using your bmp, inf and Resample and my tiff:

Are you sure you used my tiff, size 541KB, dated 30/04/2015 at 16:20?
This is strange indeed. Yes, by all means - the TIF you sent with 541 kb indeed. I still was wondering wow - what a size difference...
Okay, so there must be another part of confusion:

- I have a folder, it is called "RAF_Gutersloh_X". Inside, there are my 3 files "RAF_Gutersloh_X_original.bmp" , "RAF_Gutersloh_blendmask.TIF" and "RAF_Gutersloh_X_original.INF". Furthermore the TXT file with lat long coordinates and my resample.exe.
- My compiled BGL file is 34.39MB, I copied it into my "Scenery" folder.
- TmfViewer is LOD 16, the coordinates are limited to the RAF Gutersloh area
- I tried both bgl, the one in my RAF_Gutersloh_X "Scenery" folder and the folder "RAF_Gutersloh_X".
- I tried both versions: Creating a "texture" folder and placed both files (background.bmp and blend mask) inside and delete the texture folder and tried to use only the Scenery folder...
- I feel optimistic about my work with GIMP seems to be okay
- I am absolutely confused about it is working fine with you but not with me...

It seems to be a horrible invisible minor careless mistake...
Or might be there any possible incompatibility between some of my programms, maybe?
It is definitely a problem with your tiff.

Create a new folder and copy all files from the link to it.

Run Resample in that folder with the .inf and it should create a bgl of size 34,390KB. Drop the bgl file onto TmfViewer and it should display correctly.

If it doesn't display correctly in FSX, you must have another bgl in an active scenery area.

Okay, well - how should I discribe this mess....

You were always right, George. There had been another bgl, but called "Photo.bgl" had been hidden beside my other files - I never had considered it so far, just because I thought it would contain the original Nauru datas from the tutorial. I failed a lot. This file has to be forgotten - now I remember it was created to check as first step how to import and set a background image. Wow, worked fine! But my brain seems to be flooded by happiness hormones - I forgot to eliminate the Photo.bgl immediately...
So this was the reason to annoy you all with my superficiality - sorry for that.
Now it works, the bmp with correct blend mask appears fine in tmfViewer and also in FSX.

George, thank you for patience and help. Good to know about you guys in this forum!