Usage Instructions

Shortcut bar


Process Flow

Test images pack download link:

Note: This software does not support automatic refresh, after modifying the layout parameters, you need to refresh manually (Ctrl+R).


  1. Fill in the layout parameters in the Settings panel: Row (number of images in a row), NumPerImg (number of sub-images that will be combined into a single image), Col (number of images in a column).

  2. File->Open, select input mode:

    2.1. Sequential: Multiple images in one folder. (test_input/01)

    2.2. Parallel Auto: One folder with several subfolders, each subfolder contains multiple images. (test_input/)

    2.3. Parallel Manual: Manually select multiple folders. (test_input//01+test_input//02)

    2.4. Image File List: Import images according to a given list of filenames (TXT, CSV). (Demo file)

  3. Open the folder and import the path.

  4. After loading the images you can use the Next and Previous buttons to switch between them.

  5. Input/OutPut->OutputMode, select the output mode

  6. File->Select output path, Select the output path.

  7. Save 💾️

Keyboard shortcuts

  1. Input path:

    Sequential: Ctrl+E

    Parallel Auto: Ctrl+A

    Parallel Manual: Ctrl+M

    Image File List: Ctrl+F

  2. Output path: Ctrl+O

  3. Next: Ctrl+N

  4. Previous Ctrl+L

  5. Save: Ctrl+S

  6. Refresh: Ctrl+R (Or right mouse button)

  7. Hide toolbar: Ctrl+H

  8. Use the keyboard arrow keys (up, down, left, right) to move the image in the image panel.

Functionality description

Input mode

Sequential is a serial browsing mode. It is used to display and stitch multiple images with different filenames contained in a single folder.

Parallel Auto and Parallel Manual are parallel browsing modes (subfolders with different names). In order to compare the images, each folder or subfolder must contain the images with the same filenames.

Image File List is a custom mode. You can import a list of images from TXT or CSV file. CSV supports multi-line and multi-column mode.

For automatic image arrangement set NumPerImg to -1.

Output mode

stitch: Save the stitched image to the stitch_images directory.

select: Save the currently displaying images to a different folder. By default the images will be copied to a new location, you can select MoveFile to move them instead.

magnifer: Save all the magnified areas separately.

Automatic image arrangement

By default NumPerImg = -1 and this is an automatic layout mode. NumPerImg means that several images are combined into a single image.

If NumPerImg  = 1 or >1, then the image layout is in manual mode. In this mode Row and Col numbers can be adjusted.

Sequential browsing in a parallel mode

By selecting Parallel+Sequential option, you can simultaneously view the first n images in folders 1-12, n can be set by NumPerImg.


For example: Row=5, NumPerImg=4, Col=1 means that MulimgViewer will show 4 images from 5 parallel directories at once, 20 images in total. Check Vertical to change the image layout direction.


Parallel->Sequential: Generate a image list containing all pictures in multiple folders, and then display them in serial.

In Parallel+Sequential mode, the file name under each subfolder needs to be the same, but in Parallel->Sequential mode, it is not required.

Auto save

Select AutoSaveAll, then click Save 💾️.

Image size normalization

Fill: Image size is the largest image in a group, filling mode (keep the original pixel resolution).

Crop: Image size is the smallest image in a group, cropping mode (keep the original pixel resolution).

Resize: Image size is an average size of all the images in a group, scaling mode (don’t keep the original pixel resolution).

Gap between images


Color fill

You can use custom background and foreground colors and transparency.

Parallel Manual mode supports file list import and export

Independent display and output sizes

This feature provides independent view and output scales.

Application scenario:

  1. When you need to display a lot of images at the same time and the screen can’t fit them all, just set Scale:Show to shrink the images.

  2. Stitched images at 100% scale can be very large, but you can control the dimensions of the individual images by setting Scale:Out.

Parallel zoom

Process Flow:

  1. Click Zoom 🔍️

  1. Mouse pointer will be turned into a crosshair cursor. Now you can make a selection;

  2. To make a selection press and hold the left mouse button, drag mouse to draw a rectangle and then release the button — a magnified area will be displayed;

  3. Click the right mouse button to duplicate the selection.


  1. 🔍️KeepSize — keep the image and the magnified area aspect ratios the same.

  2. 🔍️Scale by default is set to -1,1, which means the scaling factor will be chosen automatically.

  3. Select Vertical, then press Crtl+R to place the magnified area on the right side of the original image.

  4. Use 🔍️Scale to change the magnification factor, but keep in mind that the maximum size will not exceed the original image size. For example, 3,3 means enlargement by a scale factor of 3.

  5. Box:Width is set to 2,3. The line width in the original image is 2, and the line width in the magnified image is 3.

  6. Set Box:Width to 0,0 to hide the selection border.

  7. Box:Width is set in pixels and remains the same in all zoom levels. If the selection border width is suitable when Scale:show is set to 0.1,0.1 and Scale:Out is set to 1,1, then it will probably be much thinner in the output image.

  8. After clicking Zoom 🔍️, select the image by clicking the image with the left mouse button, and then use ctrl + mouse wheel to zoom the image globally.

  9. The scroll wheel zoom function is controlled by a zoom factor. Every time you manually set Scale:Show to 1,1, the zoom factor is cleared to zero.

Adjust the position of the selection:

Note: After selecting SelectBox option you cannot make a new selection by pressing the left mouse button, but you can still duplicate an existing selection by pressing the right mouse button.

  1. Check SelectBox

  2. Position the mouse pointer inside the selection border and click the left mouse button to select it;

  3. Use the keyboard arrow keys to adjust the position of the selection; PS: press shift to change the speed or use the right mouse button to quickly move the position of box.

  4. Uncheck SelectBox.

Clear a box:

Method 1:

  1. Check SelectBox, click the left mouse button on a selection, press Del to clear the chosen selection;

  2. Uncheck SelectBox, press Del to clear all selections.

Method 2:

  1. Uncheck SelectBox

  2. Double-click the left mouse button on the image

  3. Press Ctrl+R to clear all the selections and refresh the view

Manually change the color of the zoom box.

  1. Check SelectBox

  2. Check Box:SelectBox

  3. On the original image, select a box with left click

Left click Color/transparency:Draw and select the color

  1. Do not show box/img

  2. Uncheck Box:InBox, remove the box on the original picture

  3. Uncheck Box:In🔍️, remove the box on the enlarged picture

  4. Uncheck ShowImg, the original picture will not be displayed

Uncheck Show🔍️, the enlarged picture will not be displayed

Automatic window size adjustment

Enable AutoWinSize for automatic window resizing.

Browse images, precise positioning

Move the slider for coarse positioning.

  1. Help->Index table

  2. Find the serial number of the image;

  3. Enter the serial number and press Enter.



  1. After closing Title:Auto, you can customize the display title

  2. In the Sequential input mode, the file name is 01_DSC.jpg, and the Prefix and Suffix are not selected, the file is displayed as DSC. Use numbers to sort image files.


  1. It is recommended to use the installation version _Setup.exe

  2. Copy the font 1_Calibri-Light.ttf to the installation directory C:\Program Files (x86)\MulimgViewer\font\using

  3. The smaller the number in 1_Calibri-Light.ttf, the higher the font order in the GUI

Important information and useful tips

Parallel mode

  1. Make sure that image filenames in all folders/subfolders are the same when using the multi-image modes (Parallel Manual and Parallel Auto).

  2. Subfolder naming is also important. If the names are 0,1,2…10,11, then you should change them to 00,01,02…10,11. Otherwise MulimgViewer will sort them as 0,1,10,11,2…

Recommended file renaming tool:

win10: uTools


  1. purrr.

sudo apt install purrr

  1. Thunar - Bulk Rename Files.

sudo apt install thunar

  1. Regular Expression: perl-rename

  2. find

find /path/to/folder -type f > ./filelist.txt

Multi-image stitching, high resolution images, window size issues

  1. Disable AutoWinSize and maximize the window.

  2. Adjust Scale:Show as needed. For example, 0.2,0.2 to shrink, 2,2 to enlarge images.

  3. Set TruthResolution to resize all the images to the same size for your viewing convenience.