Image Histogram
@channel curve


### probability of the occurrence Distribution
**histograms are not unique**
Invariant to changes in scale and rotation
camera apply some image enhancement based on image histogram
$$p(r_k) = probability \; of \; graylevel \; r_k$$
### Image Histogram Notion
|Title|
|:-:|
|[Image Histogram Flatting](https://texonom.com/image-histogram-flatting-50b9173a150448dea3d1138a9e38f11a)|
|[Spatial Histogram](https://texonom.com/spatial-histogram-6272abff858341c9a8ba0d1a91006073)|








