### Fixel FFT Wizard 21 July 2018

The Fourier Transform is one of the most powerful methods to analyze signals / data. It is widely used in the Image Processing world as on of the most used tool for any algorithms developer.

In this post we’ll cover the intuitive ideas behind it and how to use it for Image Restoration while avoiding the Math!

## Background

The Fourier Transform is one of the most powerful methods to analyze signals / data. It is widely used in the Image Processing world as on of the most used tool for any algorithms developer. It has a flavor specialized for Discrete Signals called Discrete Fourier Transform (DFT) which has a fast and efficient implementation called Fast Fourier Transform (FFT).
We won’t dive into the Math and ideas behind the DFT but the basic idea is pretty simple.

For images the DFT means we can represent data either by values of each pixel in a spatial grid or have equivalent representation which is the energy of periodic 2D signal.

In Digital Image Processing there are operations easier to do in the Spatial representation (Image itself) and operations easier to do on the frequency domain.

## Applications

There are many applications for the DFT in Image Processing.

For instance, Frequency Separation, which is highly popular among Retouchers, can be easily analyzed (Implemented) using DFT.

Actually many filters (See for instance ) can (Or are) be implemented in the frequency domain which under some conditions is more efficient (Faster). For instance have a look at `Custom Filter`

in Adobe Photoshop.

Affinity Photo even use FFT for Denoising (See FFT Denoise, Though it is more periodic pattern suppression, see below).

### Texture / Pattern Suppression

One of the task which is easier to do in the Frequency Domain is Texture / Pattern Suppression.

Many users use to retouch scanned images or images with periodic pattern they want to remove.

We won’t display full use case of that but you can read and watch many examples in the following resources:

- Use FFT To Reduce Texture

Blog post about DFT / FFT and how to use that to remove texture. Very clear and the work flow similar to ours. - Youtube - Photoshop FFT Tutorial

Simple tutorial and hands on on using FFT Plug In to retouch scanned images. - Youtube - FFT Photoshop Action

A continuation of the previous video about automating the work flow of dealing with scanned images and texture. - Youtube - Using FFT Filter for Photoshop to Remove Old Paper Texture

Simple tutorial on dealing with a scanned image with Old Paper Texture. - Youtube - Using an FFT Filter to Remove Repeating Patterns

Tutorial from Retouch Pro forum user. - Youtube - Pattern Suppression in Photoshop

Full tutorial, including installation, of FFT Plug In and use case. - FFT Filter With Photoshop Action

Blog post about utilizing FFT for reduction of pattern noise. - DPReview Forum - FFT Filter and Photoshop Action (Tutorial)

A tutorial posted on DPReview Retouching forum about utilizing FFT Plug In. - Lynda - Using an FFT plugin to remove paper texture

Lynda tutorial about utilizing FFT. Behind a Paywall.

All of them has the same basic idea:

- Transform the Image into Frequency Domain

Apply FFT Filter on an image in Photoshop. The filter will actually be applied on the Luminosity Data of the image.

The Plug In will yield 3 Channels image where 2 channels are dedicated to the Amplitude and Phase of the Frequency Domain. - Adjust the Amplitude of the Fourier Transform

The user will adjust (**Only**) the Amplitude. Usually by removing energy which fits the unwanted pattern. This is basically applying manual Filtering of the image. - Transform the Adjusted Frequency Data into Luminosity Image

Once the Amplitude is adjusted the use will apply the Inverse Transform (IFFT) which will result in Luminosity (Grayscale) image with the removed data according to the user applied filtering. - Merge the Adjusted Luminosity Image with the Color Image of the Original Image

Now, the last step, is merging the Luminosity data with the color data of the original image. Usually by changing the blending mode to*Luminosity*.

## Fixel FFT Wizard Photoshop Plug In

Adobe Photoshop, to our knowledge, has never offered DFT Filter integrated into Photoshop. Hence all solutions were based on Plug In’s created by 3rd party. In some of the above resources you’ll find some of those 3rd party solutions (Plug In based) yet usually they are either not working on platforms, not updated or supported.

Yet there is demand for such solutions:

- Adobe Photoshop Forum - Are There Any FFT (Fast Fourier Transform) Plug In’s for Photoshop CC?
- Adobe Photoshop Feedback Forum - Photoshop: FFT Based Pattern Remover (Filter).
- Reddit - FFT Filter.
- DPReview Forum - FFT (Fourier Filters) with Photoshop - For Larger Images.
- Luminous Landscape - Free Mac Photoshop FFT / IFFT 64-bit Plugins for CC 2015 (OS 10.9+).
- macOS Photoshop CS5, CS6, CC, CC 2015 FFT / IFFT Filters (64 BIT).
- Photoshop Gurus Community Forum - FFT Plugin for Macs by Dj Joofa Being Made Available.
- Operation Photo Rescue’s Online Community - FFT for 64bit Photoshop.
- RetouchPro - Here is FFT for 64 bit Photoshop.
- RetouchPro - Developing Mac Photoshop 64 bit FFT / IFFT Plug In’s.

So we thought we could assist the community with a product which will be supported as a commercial product but **will be offered for free** (*Pay as You Want*).

### Download

You may download Fixel FFT Wizard from our web store for free (Pay as You Want). The user will be asked for email address in order to let him know about updates.

If the user only download it as a one time one could use Temporary Email address.

### Installation

Once you download Fixel FFT Wizard you will have a ZIP file named `Fixel FFT Wizard majorVersion.minorVersion.buildNumber`

(For examples `Fixel FFT Wizard 1.0.000`

).

Inside this ZIP file you’ll find 5 files:

`Fixel FFT Wizard <majorVersion> PS.8bf`

(For example`Fixel FFT Wizard 1 PS.8bf`

) - Adobe Photoshop Plug In for Windows.`Fixel FFT Wizard <majorVersion> PS.plugin`

(For example`Fixel FFT Wizard 1 PS.plugin`

) - Adobe Photoshop Plug In for macOS.`Fixel FFT Wizard <majorVersion> UI.jsx`

(For example`Fixel FFT Wizard 1 UI.jsx`

) - Adobe Photoshop Extend Script File (Used of the UI).`Fixel FFT Wizard.url`

- Internet Link for This Page / Product Page.`Installation Guide.txt`

- Text File with Installation Guide.

#### macOS Installation

- Make sure Photoshop is closed.
- Go to the following path
`Hard Drive/Applications/<Photoshop Version>/Presets/Scripts`

. - Create a Folder named
`Fixel Algorithms`

.

You may be required for Administrator Rights to do so. - Go to the path created above -
`Hard Drive/Applications/<Photoshop Version>/Presets/Scripts/Fixel Algorithms`

.

For instance, in case`<Photoshop Version>`

is`Photoshop CC 2018`

the path becomes`Hard Drive/Applications/Adobe Photoshop CC 2018/Presets/Scripts/Fixel Algorithms`

- Copy the file
`Fixel FFT Wizard 1 UI.jsx`

into the folder above. - Go to the following path
`Hard Drive/Applications/<Photoshop Version>/Plug-ins`

. - Create a Folder named
`Fixel Algorithms`

.

You may be required for Administrator Rights to do so. - Go to the path created above
`Hard Drive/Applications/<Photoshop Version>/Plug-ins/Fixel Algorithms`

.

For instance, in case`<Photoshop Version>`

is`Photoshop CC 2018`

the path becomes`Hard Drive/Applications/Adobe Photoshop CC 2018/Plug-ins/Fixel Algorithms`

. - Copy the file
`Fixel FFT Wizard 1 PS.plugin`

into the folder above. - Launch Photoshop. Find
`Fixel FFT Wizard 1 UI`

at the bottom of the Filter menu.

#### Windows Installation

- Make sure Photoshop is closed.
- Go to the following path
`C:\Program Files\Adobe\<Photoshop Version>\Presets\Scripts`

. - Create a Folder named
`Fixel Algorithms`

.

You may be required for Administrator Rights to do so. - Go to the path created above -
`C:\Program Files\Adobe\<Photoshop Version>\Presets\Scripts\Fixel Algorithms`

.

For instance, in case`<Photoshop Version>`

is`Photoshop CC 2018`

the path becomes`C:\Program Files\Adobe\Adobe Photoshop CC 2018\Presets\Scripts\Fixel Algorithms`

- Copy the file
`Fixel FFT Wizard 1 UI.jsx`

into the folder above. - Go to the following path
`C:\Program Files\Adobe\<Photoshop Version>\Plug-ins`

. - Create a Folder named
`Fixel Algorithms`

.

You may be required for Administrator Rights to do so. - Go to the path created above
`C:\Program Files\Adobe\<Photoshop Version>\Plug-ins\Fixel Algorithms`

.

For instance, in case`<Photoshop Version>`

is`Photoshop CC 2018`

the path becomes`C:\Program Files\Adobe\Adobe Photoshop CC 2018\Plug-ins\Fixel Algorithms`

. - Copy the file
`Fixel FFT Wizard 1 PS.8bf`

into the folder above. - Launch Photoshop. Find
`Fixel FFT Wizard 1 UI`

at the bottom of the Filter menu.

### Use

The use of the filter is pretty simple.

In order to avoid quantization errors the user should use 16 Bit / 32 Bit Mode in Photoshop.

The Plug In is actionable. Feel free to build actions around it to incorporate it into your work flow.

#### Forward FFT

In order to apply the Forward FFT do as following:

- Make sure the selected Layer in the Layer panel it a bitmap layer.
- Launch the UI by
`Filter -> Fixel FFT Wizard 1 UI`

(Should be at the bottom of the Filter Menu). - On the UI Click
`Forward FFT`

.

Pay attention that if you’re in 8 Bit Mode a warning window will appear (Select`Yes`

to apply the filter in 8 Bit Mode).

The Filter will create a new layer called `Forward FFT (temp)`

with its Red Channel selected as active channel.

The channels of the `Forward FFT (temp)`

are the Amplitude (Red Channel) and Phase (Green Channel) of the image.

The Blue Channel consists the Luminosity Channel of the input image with some encoding.

#### Adjust Amplitude

By default the `Forward FFT (temp)`

will come with Amplitude Channel (Red Channel) selected.

Hence in order to adjust the amplitude just draw over the layer with any tool you find appropriate.

Make sure you don’t alter any other channel but the Amplitude Channel (Red Channel).

Otherwise the Backward FFT won’t reconstruct the image correctly.

Don’t alter the Image Mode during the use of the filter.

#### Backward FFT

The Backward FFT filter will reconstruct the Luminosity Channel based on the adjusted Amplitude Channel.

In order to apply the Forward FFT do as following:

- Activate the
`Forward FFT (temp)`

layer in Layer Panel. - Launch the UI by
`Filter -> Fixel FFT Wizard 1 UI`

(Should be at the bottom of the Filter Menu). - On the UI Click
`Backward FFT`

.

The Plug In will reconstruct the Luminosity Channel and set the Blending Mode to`Luminosity`

.

### System Requirements

#### Operating System

- Windows Windows 7 x64 (Service Pack 1 Installed), Windows 10 x64.
- macOS macOS 10.10 and above.

We suggest the Operating System to be updated to its latest build.

#### Host Program

- Adobe Photoshop 64 Bit Photoshop CS6 64 Bit. Adobe Photoshop CC 2015 64 Bit, Adobe Photoshop CC 2017 64 Bit, Adobe Photoshop CC 2018 64 Bit

It should work on Adobe Photoshop CS5 64 Bit and all CC 64 Bit versions but we never validated it.

#### Hardware

- x64 Bit CPU (Intel or AMD) with SSE4 Support.

Basically any modern CPU created by Intel or AMD since ~2010.

## Summary

The reason we created Fixel FFT Wizard was reading about the need of people for FFT Plug In in Photoshop both for Windows and macOS.

Moreover, usually the use case were old photos with sentimental significance.

So we felt we could assist and created Fixel FFT Wizard to support those people who mostly use this for keep their memories with them.

Taking all these under consideration we decided to offer Fixel FFT Wizard for free for any user without any constraint on the use.

At the moment Fixel FFT Wizard is in Public Release Candidate state and once we finalize it we’ll put it behind *Pay as You Want* offer with free option always available.

The download requires Email Address so we could notify you about updates of Fixel FFT Wizard.

We hope you enjoy it and find it useful in your work flow.

If you do, we’ll be happy if you share your cases with us.

## Resources

- Use FFT To Reduce Texture.
- Youtube - Photoshop FFT Tutorial.
- Youtube - Using FFT Filter for Photoshop to Remove Old Paper Texture.
- Youtube - FFT Photoshop Action.
- Youtube - Using an FFT Filter to Remove Repeating Patterns.
- Youtube - Pattern Suppression in Photoshop.
- FFT Filter With Photoshop Action.
- DPReview Forum - FFT Filter and Photoshop Action (Tutorial).
- Adobe Photoshop Forum - Are There Any FFT (Fast Fourier Transform) Plug In’s for Photoshop CC?
- Adobe Photoshop Feedback Forum - Photoshop: FFT Based Pattern Remover (Filter).
- Reddit - FFT Filter.
- DPReview Forum - FFT (Fourier Filters) with Photoshop - For Larger Images.
- Luminous Landscape - Free Mac Photoshop FFT / IFFT 64-bit Plugins for CC 2015 (OS 10.9+).
- macOS Photoshop CS5, CS6, CC, CC 2015 FFT / IFFT Filters (64 BIT).
- Photoshop Gurus Community Forum - FFT Plugin for Macs by Dj Joofa Being Made Available.
- Operation Photo Rescue’s Online Community - FFT for 64bit Photoshop.
- RetouchPro - Here is FFT for 64 bit Photoshop.
- RetouchPro - Developing Mac Photoshop 64 bit FFT / IFFT Plug In’s.
- Lynda - Using an FFT Plug In to Remove Paper Texture

Behind a Paywall. - Smiley Man - Introducing Fixel FFT Wizard for Scanned Photos Restoration (Korean).

Translation into English.

Key Words: Fixel Algorithms, Fixel, Fixel FFT Wizard, FFT, DFT, FFT Filter, FFT Plug In, DFT Filter, Image Restoration, Scanned Image Restoration, FFT Image Restoration, Photoshop, Plug In, Photoshop Plug In.