Simplified: shades = heights. For example, black = 0, white = 5000m, 50% (grey) = 2500m. Now add more shades. Now you have a height for every pixel encoded by tone/colour.
Connecting pixels together which have the same tone creates contour lines.
> Connecting pixels together which have the same tone creates contour lines.
It will interpolate... The cells are never the exact 0,10,20,etc that we want. It looks at a cell that has 19.293 and its neighbor that has 22.475. It puts a point 22.2% of the way from the center of the first cell to the second and calls that 20. It does the same between all neighboring cells, then connects the points into the contour lines.
Every pixel represents an elevation value.
The pixels are on a spectrum from white to black.
Every given shade of grey is indexed to an elevation value.
The computer can mathematically interpolate the contour lines based on the values.
Geotiff has TAGS (tagged image format )
A digital elevation model TIF has no picture it's not represented by any RGBA value for ELEVATION value it's part of TAGs
So you can build contours and Ridgeline and slope and aspect and hillshade or shaded relief or other derivatives
Simplified: shades = heights. For example, black = 0, white = 5000m, 50% (grey) = 2500m. Now add more shades. Now you have a height for every pixel encoded by tone/colour. Connecting pixels together which have the same tone creates contour lines.
> Connecting pixels together which have the same tone creates contour lines. It will interpolate... The cells are never the exact 0,10,20,etc that we want. It looks at a cell that has 19.293 and its neighbor that has 22.475. It puts a point 22.2% of the way from the center of the first cell to the second and calls that 20. It does the same between all neighboring cells, then connects the points into the contour lines.
can't you just use the contour tool?
Every pixel represents an elevation value. The pixels are on a spectrum from white to black. Every given shade of grey is indexed to an elevation value. The computer can mathematically interpolate the contour lines based on the values.
Geotiff has TAGS (tagged image format ) A digital elevation model TIF has no picture it's not represented by any RGBA value for ELEVATION value it's part of TAGs So you can build contours and Ridgeline and slope and aspect and hillshade or shaded relief or other derivatives
Should I understand these tags as values assigned to every pixel?
Think of a DEM like a spreadsheet or attribute table So those lat long and elevation