Scale the gray values of an image.
The operator scale_image scales the input images (Image) by the following transformation:
g' := g * Mult + Add
If an overflow or an underflow occurs the values are clipped.
This operator can be applied, e.g., to map the gray values of an image, i.e., the interval [GMin,GMax], to the maximum range [0:255]. For this, the parameters are chosen as follows:
Mult = 255 / (GMax-GMin) Add = - Mult*GMin
The values for GMin and GMax can be determined, e.g., with the operator
min_max_gray.
|
Image (input_object) |
(multichannel-)image(-array) -> object : byte / int1 / int2 / uint2 / int4 / real / direction / cyclic / complex |
| Image(s) whose gray values are to be scaled. | |
|
ImageScaled (output_object) |
(multichannel-)image(-array) -> object : byte / int1 / int2 / uint2 / int4 / real / direction / cyclic / complex |
| Result image(s) by the scale. | |
|
Mult (input_control) |
number -> real / integer |
| Scale factor. | |
| Default value: 0.01 | |
| Suggested values: 0.001, 0.003, 0.005, 0.008, 0.01, 0.02, 0.03, 0.05, 0.08, 0.1, 0.5, 1.0 | |
| Typical range of values: -255.0 <= Mult <= 255.0 | |
| Minimum increment: 0.001 | |
|
Recommended increment: 0.1 | |
|
Add (input_control) |
number -> real / integer |
| Offset. | |
| Default value: 0 | |
| Suggested values: 0, 10, 50, 100, 200, 500 | |
| Typical range of values: -512.0 <= Add <= 512.0 | |
| Minimum increment: 0.01 | |
|
Recommended increment: 1.0 | |
/* Complement of the gray values: */ scale_image(Bild,Invert,-1.0,255.0,).
The operator scale_image returns the value 2 (H_MSG_TRUE) if the parameters are correct. The behavior in case of empty input (no input images available) is set via the operator set_system(::'no_object_result',<Result>:) Otherwise an exception treatment is carried out.
scale_image is reentrant and automatically parallelized (on tuple level, channel level, domain level).
mult_image, add_image, sub_image
Image filters
