Creation of Contour from aerial Imagery

[B_RPanta]

Hi,

I have aerial imagery (colour) in Tiff format. Can anybody help me to create contour from this aerial imagery? I am using ArcGIS9.2.

Thanks in advance.

Regards,
Pantha

[PavanYadav]

Greetings,
Is it a 3-band (RGB) image? If so, it only contains landscape colors not elevation information. If your study area is in the USA, you may get a DEM (Digital Elevation Model) from the USGS website.  If you already a DEM for your study area you can use Contour tool (you will need 3D or Spatial Analyst extension). You might find the following resources helpful:
http://seamless.usgs.gov/about_elevation.php
http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//009z000000ts000000.htm
http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/How_Contouring_works/009z000000vq00000...

Regards,
Pavan