Color Sieve

Create a dramatic and unusual look for your photos! This app produces a "selective color" effect by retaining saturated, pure colors and changing unsaturated, muted colors to shades of gray. Scenes with a few areas of bright color produce especially interesting results, causing key colored objects to "pop" against a monochrome background.

Color Sieve automatically selects areas to make colored or gray. Unlike many other selective color apps, it does not require you to manually paint in colored regions.

Using Color Sieve is easy as 1 - 2 - 3:

1) Tap "Load" to load an image from your photo album, or "Snap" to snap a new one using the built-in camera.
2) Tap the screen to adjust the effect. The vertical tap location controls the saturation level threshold for color retention. Horizontal tap location adjusts the abruptness of the transition from gray to color.
Tapping the bottom right corner produces a full color image, tapping the upper left corner produces a grayscale image, tapping elsewhere produces intermediate results. The screen image updates in a fraction of a second after each tap, showing the effect of the new setting.
3) When you like what you see, tap "Save" to save a full-resolution image to your photo album. Note that because as many as eight million pixels are processed this may take several seconds.

As a bonus, a two finger tap inverts the effect, so that bright colors become gray and dull colors are retained. A second two finger tap un-does this a reverts to the normal mode.

Please visit http://podapodadev.com for additional information and example images.
Have fun and experiment!

更新履歴
1) "Tap-to-select" color picking. Tap on the screen image, and the hue at the tap location is retained, and unlike hues are changed to gray shades.
2) Expanded help screens explaining new the new function.