# imhist

Histogram of image data

## Syntax

## Description

`[`

calculates the histogram for the grayscale image `counts`

,`binLocations`

]
= imhist(`I`

)`I`

. The
`imhist`

function returns the histogram counts in
`counts`

and the bin locations in
`binLocations`

. The number of bins in the histogram is
determined by the image type.

`[`

specifies the number of bins, `counts`

,`binLocations`

] = imhist(`I`

,`n`

)`n`

, used to calculate the
histogram.

`[`

calculates the histogram for the indexed image `counts`

,`binLocations`

] = imhist(`X`

,`cmap`

)`X`

with
colormap `cmap`

. The histogram has one bin for each entry in
the colormap.

## Examples

## Input Arguments

## Output Arguments

## Tips

For grayscale images, the

`n`

bins of the histogram are each half-open intervals of width*A*/(*n*−1). In particular, the*p*th bin is the half-open interval$$\frac{A(p-1.5)}{(n-1)}-B\le x<\frac{A(p-0.5)}{(n-1)}-B,$$

where

*x*is the intensity value. The scale factor*A*and offset*B*depend on the type of the image class as follows:Data Type *A**B*`double`

`1`

`0`

`single`

`1`

`0`

`int8`

`255`

`128`

`int16`

`65,535`

`32,768`

`int32`

`4,294,967,295`

`2,147,483,648`

`uint8`

`255`

`0`

`uint16`

`65,535`

`0`

`uint32`

`4,294,967,295`

`0`

`logical`

`1`

`0`

To display the histogram from

`counts`

and`binLocations`

, use the command

.`stem`

(binLocations,counts)

## Extended Capabilities

## Version History

**Introduced before R2006a**