arts102





Noise Assignment








Noise Definition
 

Noise is one of the classic problems and processes used in image processing work. Noise is random information. Signal is planned information. All signals have certain amounts of noise in them. Some of it is not visible. For instance when you take a digital photo in dark situations, you will notice that all the pixels have additional color noises added due to the fact that the camera is created to give best results at bright light levels. Read Image noise before proceeding further.


Noise / Signal
  Engineering research is dedicated to improving systems, one way is to enhance signal over noise. New cameras are designed to feature higher resolution, greater precision with fewer noisy artifacts.


Noise in Art
  Artists tend to like noise. They use it in sound, in images, they also like to explore the metaphorical meaning of noise. Noise is added to processes to create variations, and therefore allow for testing of the processes to see if results will diverge. Review the artwork of the early 20th century Futurist Russolo (Art of Noise) and listen to the Musique Concrete [1] sound works of the composer Pierre Schaeffer who assembled soundtracks in the late 1940's. Xenakis [Orient-Occident], Ryoki Ikeda [1][2][3]. Skrewell, d_time


Noise in Photoshop Start with a blank white, or middle grey or black image.
Go to FILTER, select NOISE, use ADD NOISE to add texture/noise to each of the pixels in your image.
Blend all the pixels by using FILTER, BLUR, GAUSSIAN BLURm using a high value like 52 pixels
(Your image should look flat, blended grey)
Go to IMAGE, ADJUSTMENTS, EQUALIZE to even out the tonal range. Your image should have color forms. If there is any sharp blending, then go back to blur and even out the sharp edges again.
Once you have done this exercise, explore other ways by which to create noise, for instance through compression when you save an image.


Noise Thru Compression

If you save a jpeg with very low compression, the process will add artifacts to your image. If you then open and resave again, additional artifacts will be added. If you continue, you will quickly see how the compression process has particular kinds of patterns that are imposed on the image, and could potentially be of interest in our study.


Image Processing Menu

Photoshop has an image processing menu that highlights all the functions that are specific to image processing. I highly recommend that you select this to let you know which tools are relevant for our study of Photoshop as an image processing tool. Do the following:
- Open an image
- Go to EDIT, MENUS
- at SET, select IMAGE ANALYSIS
All of the relevant tools in Photoshop will now be highlighted.


Our Noise Assignment Create 5-10 different images, appx 720x580, or 800x600 that are a result of noise, bad compression, etc. The intent is to arrive at interesting results and processes. Keep track of how you have achieved your images to share with the class.