Command Line Options

we have improved/added command line options for nomacs:

Usage: nomacs.exe [options] image

-?, -h, --help                                  Displays this help.
-v, --version                                   Displays version information.
-f, --fullscreen                                Start in fullscreen.
-x, --pong                                      Start Pong.
-p, --private                                   Start in private mode.
-m, --mode <default | frameless | pseudocolor>  Set the viewing mode <mode>.
-d, --directory <directory>                     Load all files of a
-t, --tab <images>                              Load <images> to tabs.

image                                           An input image.

Brand your nomacs

Since nomacs 3, you can change the background image which is displayed on start-up. You just need to place an image called ‘bg.png’ into a folder together with your nomacs.exe. Here is how this looks like:tu-branding

If you add a second file named ‘bgf.png’, the splash screen of the frameless mode will be overwritten.

Tiny Planet

nomacs can turn your photo spheres into Tiny Planets. Therefore, you first need to capture a photo sphere. Here is how you do this in your camera app on Android:

photo-sphereIn nomacs you can choose Edit > Tiny Planet to turn your favorite photo sphere into a tiny planet.

img-2015-12-17 16.50.43In the Tiny Planet dialog, you can adjust the planet’s size and orientation. And here is how the result looks:kalenberg-new-ps

Unattended Installation

When using Windows you can make an unattended installation of nomacs. Therefore you need to place install-script in a folder together with the nomacs-setup.exe. Then you can call
nomacs-setup.exe --script install-script.js
If you want to change the target directory, you can edit the following line in the install-script.js:

// Choose a target dir -----------------------------------------------------
// installer.setValue("TargetDir", "C:/nomacs");

Moreover, which components to install can be changed here:

// Select your components -----------------------------------------------------
// var page = gui.currentPageWidget();
// page.selectComponent("nomacs.x86");
// page.deselectComponent("nomacs.x64");
// Select your components -----------------------------------------------------

Local Repository

you can install nomacs using a local repository. Therefore you need to clone the current repository: http://download.nomacs.org/repository.zip. Extract this repository to a local server or machine.

Insalling from the Local Repository (GUI)

On the first page of the nomacs installer click the Settings button. Then add a User Defined Repository and uncheck the Default Repository. You can additionally add user credentials if needed (see screenshot).

img-2016-01-12 11.53.39-bInstalling from the Local Repository (CMD)

Open the nomacs-setup.exe or maintainancetool.exe from the Windows command line. Then type:

nomacs-setup.exe --addRepository <URI,...>

Configuring Presets (Export Settings)

If you want to automatically configure some settings, you can adjust nomacs on your machine. Then, run regedit.exe and choose the settings key you want to export:

regedit /e C:\nomacs-settings.reg "HKEY_CURRENT_USER\SOFTWARE\nomacs\Image Lounge"

If you run nomacs-settings.reg on the client machine, all your settings will be applied there.

Batch Processing

nomacs supports batch processing since version 2.4. You can open the bach processing from the Menu > Tools > Batch Processing. Currently there are four different processing modes (Copy/Rename | Image Format Conversion | Image Resize | Transforming).

First you can choose the directory and select the files you want to process. File selection is similar to the thumbnail preview (select multiple files using CTRL, hold SHIFT to select files consecutively or hit CTRL+A to select all files of a folder). You can additionally filter a subset using search terms or regular expressions (in the example below all files are chosen which start with a lower case character). After selecting the files to be processed you can click the Icon Add Files to the File List. If you open the File List Tab, you can also drop multiple folders to select their files for processing. Having selected the files to be processed, you can choose an output directory. The output panel allows you to choose the old filename or rename all processed files. The screenshot shows a file conversion where 87 files are converted to png.


The Output panel allows you to choose an output directory and rename/convert files. You can choose a custom filename. Do not forget to add a sequence number such that the filenames are still unique. The filename preview picks a selected image and shows the old and the new filename accordingly. If input and output directory are the same, images will be renamed in place. Otherwise the images are copied and renamed. This action will not change the image encoding.

the output panel
the output panel

Image Conversion

If you want to convert images to a specific output format (e.g. PNG) you can change the Keep Extension drop down to Convert To. Then select your preferred format. You can choose any format which is supported by nomacs.

batch convert images
batch convert images


Click the + next to Resize/Transform to apply an image transform. If you e.g. want to downsample all images of a folder, you can choose Long Side in the resize panel. Then enter the desired side length in pixel. This option will resize the image such that the width of panorama images or the height of portrait images will be set to the desired pixel length. If you check Shrink Only images which have a lower long side than the desired length will not be resized.

batch resize
batch resize

The Transform panel allows you to rotate or flip all images. The gray text next to the panel title indicates if a panel is active or not. The example below shows a configuration which resizes all images by 50% and then rotates them by 180°.

batch transform
batch transform


After you configured the batch processing according to your needs you can hit OK. A progress bar will appear which indicates the percentage of images already processed. If you notice a wrong configuration, you can cancel the processing. All images processed will stay the same then but the processing is stopped immediately.

processing images
processing images

All processing actions are logged. Choose Show Log to see the status of the processing. You can see the status of every batch module and check if it was processed successfully. Please check the batch configuration before Processing especially if you check Overwrite Existing files since these actions cannot be reverted.

log file
log file

Overview Panel (Zooming)

The Overview Panel (Menu > Panels > Overview) enhances zoom and pan. The blue rectangle shows the current viewing area. You can pan to a specific location by dragging this rectangle to the desired position. The scrollbar at the bottom allows you to zoom. If you want to zoom to a desired factor (e.g. 600 %) you can mark and replace the text accordingly.

Overview Panel
Overview Panel

But which image format should I take?

Since we see a lot of people choosing the wrong image formats on a daily basis, we have created a short cheat sheet for you. Though JPEG is probably the easiest way to archive your pictures, there are several incentives to choose another image format depending on the image content or purpose. (You can also download the cheat sheet)

Image formats for photos
Image formats for photos
Image formats for illustrations
Image formats for illustrations

– the nomacs team


With the synchronization it is possible that multiple viewers perform the same action (like panning, zooming, etc.). This feature is useful when comparing two images.

Synchronization on the same computer

For synchronization on the same computer at least two instances of nomacs have to run. Via the “Sync”-Menu it is possible to connect to all viewers or a specific viewer can be chosen by selecting the image title of this viewer. Additionally it is possible to connect two viewers by keeping the CTRL and ALT key pressed and drag from the image of one viewer to the other. For actions which should be performed on all connected instances the ALT key has to be kept pressed (e.g. hold the ALT key pressed and use the mouse wheel for zooming on all connected viewers).

Possible actions which can be performed:

  • Panning ALT+mouse
  • Zooming ALT+mouse
  • load next/previous File (ALT+right resp. ALT+left)
  • synchronize zoom level and position in the image with CTRL+D
  • overlay the two images and change the opacity of one image with CTRL+TAB
  • arrange synchronized viewers with CTRL+SHIFT+TAB

Synchronization in the local network (LAN)

First you have to enable “network sync” in the network preferences of nomacs on all computers  you want to use. To synchronize viewers via the local network one nomacs has to start the server using the menu. The viewer on the other computer can then connect to the server.  Additional to the actions on the same computer (see above) images can also be sent over the network by pressing ALT+I (or using the menu:  Sync -> Send Image).

In the settings dialog actions can be forbidden for all clients (see Settings-Network). So you can forbid a client e.g. to zoom into your image and/or to send you new images.

Note: If a server connects to another server in the network, all clients of this server disconnect and establish a new connection to the target server. Also the server of the current viewer is stopped.