This semester I am starting Aerial Photography and Remote Sensing. For this week's lab, I learned all about identifying various features and aspects of aerial images. I essentially had three primary exercises, I will show you the final maps for the first two and talk briefly about the third.
For the first exercise, I was able to distinguish two aspects of aerial photographs. Tone and Texture. The tone in an aerial image is how bright or how dark a section of an aerial image is while the texture is how smooth or how coarse a surface of the image area is. For this map, I selected 5 areas of tone (in red) that range from very light, light, medium, dark, and very dark. For texture, additionally, I selected 5 areas of texture (in blue) that ranged from very fine, fine, mottled coarse and very coarse. The results of my first map can be seen below:
For the second exercise, I distinguished aerial photography features based on four specific criteria: These criteria are a shadow, pattern, shape and size, and association. For shadow, I used the shadow of the object to identify features (such as a power pole). For shape and size, I used just that such as the shape and size of a vehicle. Pattern, I used identified clusters such as a cluster of buildings or trees, and for association I used a grouping and contextual location such as buildings with a big parking lot being a potential mall.
Finally, for the third and final exercise, I picked points on a true-color image and compared them to the same locations on a false-color infrared image. This was a really cool exercise as true color locations showed up opposite as false-color (an example being a forest that is green in the true-color image and red in the false-color infrared image.
~Map On!
No comments:
Post a Comment