# isheart2

Inverse shearlet transform

## Syntax

``imrec = isheart2(sls,cfs)``

## Description

example

````imrec = isheart2(sls,cfs)` returns the inverse shearlet transform or shearlet synthesis based on the shearlet system `sls` and the shearlet transform coefficients `cfs`. The `isheart2` function assumes `sls` is the same shearlet system used to obtain the transform coefficients `cfs`.```

## Examples

collapse all

Load an image and create a shearlet system that can be applied to the image.

```load shapes [numRows,numCols] = size(shapes); sls = shearletSystem('ImageSize',[numRows numCols],'NumScales',4)```
```sls = shearletSystem with properties: ImageSize: [512 512] NumScales: 4 PreserveEnergy: 0 TransformType: 'real' FilterBoundary: 'periodic' Precision: 'double' ```

Obtain the shearlet coefficients of the image.

`cfs = sheart2(sls,shapes);`

Take the inverse transform of the coefficients. Check for perfect reconstruction.

```imrec = isheart2(sls,cfs); norm(imrec-shapes,'fro')```
```ans = 7.6938e-14 ```

## Input Arguments

collapse all

Shearlet system, specified as a `shearletSystem` object.

Shearlet transform coefficients, specified as a real- or complex-valued 3-D array. The 3-D array `cfs` is an M-by-N-by-K matrix where M and N are equal to the row and column dimensions of the original image. The size of the third dimension, K, is equal to the number of shearlets including the lowpass filter, K = `numshears(sls)` + 1.

The `isheart2` function assumes `sls` is the same shearlet system used to obtain the transform coefficients `cfs`.

Data Types: `single` | `double`
Complex Number Support: Yes

## Output Arguments

collapse all

Inverse shearlet transform or shearlet synthesis, based on the shearlet system `sls` and the shearlet transform coefficients `cfs`. The size of `imrec` is equal to the size of the original image. The data type of `imrec` matches the Precision value of the shearlet system.

Data Types: `single` | `double`

## Extended Capabilities

### Topics

Introduced in R2019b

## Support Get trial now