TAMS / Java / Hades / applets: contents | previous | next | ||||
Hades Applets contents visual index introduction std_logic_1164 gatelevel circuits delay models flipflops adders and arithm... counters LFSR and selftest memories programmable logic state-machine editor misc. demos I/O and displays DCF-77 clock relays (switch-le... CMOS circuits (sw... RTLIB logic RTLIB registers Prima processor D*CORE MicroJava Pic16 cosimulation Mips R3000 cosimu... Intel MCS4 (i4004) image processing ... color channels JPEG compres... Sobel filter Gauss filter resize rotate chessboard gamma correc... saturation chroma-keying chroma-keying purple fringing red-eye [Sch04] Codeumsetzer [Sch04] Addierer [Sch04] Flipflops [Sch04] Schaltwerke [Sch04] RALU, Min... [Fer05] State-Mac... [Fer05] PIC16F84/... [Fer05] Miscellan... [Fer05] Femtojava FreeTTS | Gamma correction
Circuit Description
A demonstration of contrast and brightness manipulation using the
GammaFilter component.
The filter uses three parameters:
value = k * (rgb - b)^(gamma) Note that the pixel values (rgb and b) are used as integers in the interval [0 .. 255] instead of prescaling them to the [0 .. 1] interval. Typical (useful) ranges are k=[-1.0 .. 2.0], gamma=[0.0 .. 3.0] and b=[-100 .. 100]. Obviously, setting k=1.0, b=0, and gamma=1.0 results in the identity transformation. If you set gamma=1.0, you can change the image contrast and brightness linearly via the k contrast and b offset parameters, while a gamma value unequal to 1.0 results in a non-linear transformation.
| |||
Print version | Run this demo in the Hades editor (via Java WebStart) | ||||
Usage | FAQ | About | License | Feedback | Tutorial (PDF) | Referenzkarte (PDF, in German) | ||||
Impressum | http://tams.informatik.uni-hamburg.de/applets/hades/webdemos/00-intro/02-imageprocessing/gamma.html |