Resampler

[Guest]

Hi,I have a satellite photo , 1m resolution ,1280*960 24 bit. I want to use it with resampler and create an .inf file. Resample worked and created 4 images with 256*256 ....Is it right becouse it makes a square with 512*512 but my image is 1280*960.. And if you think this 4 images as each parts of a square divided to 4 my image is mush smaller than 512*512 and it is aligned to right.The left part of this square is black .So the half of the 2 bmp images that resampler create , are all black and when I run scenery in FS , my photo covers a small area ,and there are a big black area too. I tried to create inf files manuelly and

[Guest]

Hi Kenan, your issues are well understood. It can be confusing at first.First, your image number of pixels has very little to do with the final number of pixels resample displays. Hopefully this will make more sense in a minute.There are two resample.exe files available today. YOu are using the new one. I'd recommend downloading the fs2000 terrain sdk, and using that one, it works the same, except instead of black it displays nothing in that area, which I find easier to work with.Now the MEAT of the explanation:You have a photo, and it covers a geographic area. That area is not a function of how many pixels in the photo except thru a ratio called resolution. So you say you have 1m resolution to a 1280x960 pixel image, so you'd figure your image covers 1280x960m. Now the limitations of photoreal scenery in fs2k2: your display will be 4.8m/pixel REGARDLESS of the source image resolution. :-(( Your photo will only have about 266x200 pixels at 4.8m/pixel, and that seems too small to cover an LOD13 grid, yet you see a display...that's wierd, perhaps cuz your geographic spread in what did display is 4 times too much...dunno...anyway, check that, cuz I've never had success with that small a geographic coverage.....on with the theory.Another limitation: Only COMPLETELY FILLED grids of LOD13 will display.LOD system: This is also described in the fs2000 terrain sdk, so do read that but heres the gist....MS divided the world into 6 segments, cutting latitude at the equator, and longitude at 0, +120, and -120. This is "LOD 0". Obviously these segments are oddly shaped, like the skin of half a grapefruit cut in thirds. Because longitude lines are not parallel, we can mathmatically ignore this odd shape as long as we continue to use degrees as our unit of distance.Every higher number lod grid is finer by cutting the previous segment in half both in latitude and longitude.So LOD 1 grid in latitude cuts at -45, 0, and +45 degrees, and LOD1 longitude cuts at 0, -60, -120, -180, +120, +60.continue this way until you reach LOD 13, and you can envision this pretty fine grid overlaying the world with precise definition as to the latitude and longitude boundarys for the grids. The trick in knowing predictably what part of your photo will display is in knowing where the LOD13 grid lays over your photo.to do this, you first need to know the location of some feature on your photo in terms of longitude and latitude. If you know two features locations, then its a peice of cake. If this is the case, you can use my spreadsheet, enter the two points and relevant pixel counts I ask for in the input cells and the rest will be calculated for you.Once the LOD13 grid is filled, resample will produce a 256x256 pixel image for the display of that lod grid...see how before an after pixel count is not directly connected.Resample does a lousy job of changing the resolution of your source photo, so I recommend doing that in a graphics program before you use resample.exe.Hope this helps...many other posts have been written in the terrabuilder forum...do read them, and good luck.Bob Bernstein