gen_random_region — 创建一个随机区域。
gen_random_region( : RegionRandom : Width, Height : )
算子 gen_random_region returns a random region.
During this process every pixel in the image area
[0...Width-1][0...Height-1] is adapted into the region with
the probability 0.5.
The created region can be imagined as the
threshold formation in an image with noise.
This procedure is particularly important for the creation of uncorrelated binary patterns. The random pattern is created by the C function “nrand48()”.
If Width and Height are chosen large
(> 100) the created region may require much storage space due to
the internally used runlength coding.
The gray values of the output region are undefined.
Width (输入控制) extent.x → (integer)
Maximum horizontal expansion of random region.
默认值： 128
建议值： 16, 32, 50, 64, 100, 128, 256, 300, 400, 512
值范围：
Width
(lin)
最小增量： 1
建议增量： 10
限制：
Width > 0
Height (输入控制) extent.y → (integer)
Maximum vertical expansion of random region.
默认值： 128
建议值： 16, 32, 50, 64, 100, 128, 256, 300, 400, 512
值范围：
Height
(lin)
最小增量： 1
建议增量： 10
限制：
Height > 0
The worst case for the storage complexity for the created region (in byte) is: O(Width * Height * 2).
如果参数值正确，算子 gen_random_region 返回值 2 ( H_MSG_TRUE )。否则将抛出异常。
The clipping according to the current image format is set via the
operator set_system('clip_region',<'true'/'false'>)。
gen_checker_region,
add_noise_distribution,
add_noise_white,
reduce_domain
基础