Fotocx    24.40

Fotocx is a free open source Linux program for photo/image editing and collection management. The goal is to meet the needs of serious photographers while remaining fast and easy to use.

Click the image above to see a full-size image.

Short Overview
Navigate a large image collection using a thumbnail browser, click on an image to view or edit. A rich set of edit and retouch functions is available. Import RAW files and edit with deep color. Save revised images as JPEG, PNG (8/16 bits/color), or TIFF (8/16). Select an object or area within an image (freehand draw, follow edges, flood matching tones...), apply edit functions, copy and paste, resize, blend, warp, etc. without using layers. Edit functions have fast feedback using the full image or selected zoom-in area. Edit image metadata (tags, geotags, dates, ratings, captions...). Search images using any combination of metadata and file and folder names or partial names. Click a marker on a scalable world map to view all photos from that location. Batch functions are available to rename, add/revise metadata, copy/move, resize, convert format. Fotocx uses your image files wherever they are and maintains a separate index for fast searching. Fotocx is standards compliant and can be used with other photo programs (no lock-in). Fotocx is easy to use but unconventional, so read the user guide (at least the first few pages) before jumping in. Fotocx has deep functionality. Do not expect to master it in a few minutes.

A more detailed description and list of capabilities can be found at the end of this document:
Fotocx Long Overview
Fotocx Demo (YouTube video)
A basic overview of Fotocx.

Fotocx Sample Images (YouTube video)
A collection of before/after images edited with Fotocx.
The latest release can be obtained here: downloads.
Packages for many Linux flavors can be found HERE and HERE.

Fotocx works best on a strong computer (4+ CPU cores, 8+ GB memory). 64-bit Linux is required. Lesser computers may be slow or may fail to edit large images. The monitor should be at least HD (1920x1080) and have accurate color.
Performance and Limitations
Most image edit functions respond within 1 second for images up to 20 megapixels on a strong computer. 200 megapixel images can be edited on a computer with 16 GB RAM. Composite functions (panorama, HDR ...) may need a minute or more when combining many large images. Image search time is generally below 1 second for collections up to 300K images.

Usage Examples
Click on the small images to see a full-size image.

View a large collection of image files using a thumbnail gallery. Click on a thumbnail to view or edit a full-size image. Move around within gallery pages and navigate to other pages. A gallery may be a folder of image files, the output of an image search, or an album (ordered set of images). The thumbnails can be large or small and can be zoomed out to any scale with the mouse wheel. Images can have geotags (via camera GPS or manually added). A scalable world map shows image location markers. Click on a marker to get a gallery of images.

RAW file import
The first image is the JPEG produced by the camera. The 2nd image is the RAW file from the camera, converted to TIFF-16. The 3rd image is the edited TIFF file saved as a JPEG file. The dark areas were lightened and color was slightly increased.

RAW files can be directly opened and edited, or you can use a batch function to select and convert many RAW files at once. The speed is 2-4 seconds per file on a strong PC. The converted files can be JPEG, TIFF (8 or 16 bits per RGB color), or PNG (8 or 16 bits). All internal editing is done with 24 bits per color.

Search Images
Add tags (keywords), geotags, titles, captions, dates, and ratings to images. Search images using these criteria as well as image file and folder names. Partial matching also works. Matching images are shown in a thumbnail gallery. Click a thumbnail to view or edit, or step through sequentially. Search speed is nearly instantaneous.

Tags, etc. are stored inside the images using EXIF and IPTC standards. They can be shared with other standards-compliant photo programs.

Search Metadata
Find images with any desired metadata, show thumbnail images with metadata text. Click a thumbnail to view full-size. There are also functions to view the key metadata for an image, view all available metadata, or edit any metadata.

The search speed is almost instantaneous for 'main' (indexed) metadata. The speed is slower (up to 2000 images / second) for metadata that is not indexed and must be read from the image files.

You can optionally add metadata items to the index for fast searching.

Cameras with GPS receivers can add geotags (location name and earth coordinates) to images automatically. Fotocx also has a function to find the earth coordinates for a given location (city, park, monument ...) and add geotags to a bunch of images at once. If many photos made in one location are located together in your collection, you can quickly process all of them. If this work has been done, you can use the following geotag functions to find and display images from a given location as a gallery of clickable thumbnails.

Search Images Using Geotags

List image locations: group by country, country/location, or country/location/date. Click on a list entry to see all the images in that group as a gallery of thumbnails. The example here shows 28 photos made in Jan. 2012 at Achensee, Austria. If listing by dates, you can consolidate dates that are separated by less than a given number of days.

Search Images by Clicking on a Map
Click on a map location to instantly see all the photos made in or around that location. Location names pop up as you move the mouse over the map. In this case, "Leipzig" was clicked to retrieve 25 photos of Leipzig.
Search Images Using a Calendar

The calendar report shows image counts by year and month. Click on any month to get an instant gallery of images for that month.

Edit Selected Object or Area

Little Mermaid was back-lighted. The fix was to select her and flatten (spread out) her brightness distribution. Areas are selected using the mouse: freehand draw, follow edges, or spread into matching tones from the mouse position outwards. Edge effects can be automatically blended out.
Copy and Paste Selected Areas

Drag into position, resize,
edit colors, etc.

Select Complex Edges
Hair and other irregular shapes can be accurately selected. Drag over the area with the mouse, clicking as needed on colors to be selected or suppressed. This can be tedious if the background contrast is weak. This example is about a 10 minute project for an experienced user. Novices will need time to get the feel of this tool.

Flatten Brightness Distribution
This tool is an easy way to improve detail in areas that lack contrast. Uses a single sliding control with live feedback. Sometimes works miracles and sometimes not very effective. Good for fog/haze removal.

Other tools to auto-improve images:
Local Contrast: bring out detail in low contrast areas
Gradients: increase low brightness gradients only

Use within selected areas for local optimizations.
Global and Zonal Retinex

This tool can be used to restore the full color range for a badly faded photo or one with an extreme color caste. It can also be used to add flair to any image. The original and modified images can be blended in any ratio.

View 360°Panorama Image
This tool is used to view a 360°panorama image. Use the mouse to rotate the viewpoint through the full 360°. The view window is 90°(right image) and can be zoomed-in for a larger/narrower view.
Sharpen Image

Comparison of different sharpening methods on a blurred image.

The 'gradient' method increases sharpness about as well as the classic 'unsharp mask' method, but with less "halo" effect around high-contrast edges. 'Kuwahara' produces excellent sharpness but small details are lost.

Noise Suppression

Reduce noise in photos made under low-light conditions.

Which method works best depends on
image and noise characteristics.

Measure image noise

Noise can be measured and noise suppression
can be quantitatively evaluated.

Watermark an Image

Add embedded text with various styles.

Revise Brightness by Editing a Curve

Edit a brightness curve while watching the live output image.


Remove fog and haze with Defog tool.


Compensate for radial brightness loss (vignetting), or highlight some part of the image. Response curve can be customized, saved and reused. Use the mouse to set the center for the response curve. Image can be brightened or darkened, or a color-caste can be added or removed.

Smart Erase
The power lines and poles were erased. Select an object to erase using the mouse like a paintbrush. Click to erase. Neighboring pixels replace the erased area. This usually works well for small or narrow areas, or even larger areas when surrounded with fairly uniform background, like sky or grass. Selecting long thin objects like power lines is done by clicking positions along the length.

Remove Dust

Remove the dust spots from images made from dusty scanned slides or old photo prints.
Remove Chromatic Aberration (color fringes)
Click to enlarge and view carefully. The left image is a cutout of the top right corner of a much larger image. Chromatic aberration is apparent as red and green fringes on dark-bright feature edges. The right image is a cutout of the same area from the corrected image. The correction is not 100%, but close. The original image is 18 megapixels. The correction needed about 4 seconds on a 3 GHz computer.

Increase contrast where it is weak without changing overall contrast.
Watch the image change as you move a curve or slider.

This one was taken to extremes, giving the impression of an illustration.

Tools for Brightness and Contrast

5 methods to change brightness and contrast
Remove Motion Blur
Compensate camera or subject motion.
The camera was panned during the exposure to create motion blur. This was mostly removed using the Richardson-Lucy method. Drag the mouse to indicate the blur angle and input an estimated blur span. Vary inputs to optimize result. For subject motion, use Select Area to isolate the blurred subject from the sharp background.
HDR - High Dynamic Range Image
The lower image is a composite of the upper ones. Brighter areas were taken mostly from the darker image, and darker areas from the brighter image. Optionally use editable curves to adjust the contribution of each image for each brightness level.

Gradients tool was used after the images were combined.

The camera was hand-held. The automatic alignment works well unless the camera is shifted significantly between shots. The people moved between the photos, so ghosting can be seen.

HDR made from photos having significant camera movement and rotation.
Minor changes in image scale are compensated.
HDF - High Depth of Field
Combine multiple photos of the same subject, each having a different focus distance. The combined image has a depth of field spanning all the input images. This function is very sensitive to changes in camera position or aiming point - these cause parallax errors and changes in image scale that cannot be fixed with simple translation and rotation. The software compensates for small errors in scale. If you are careful not to move the camera too much, you can get good results. All photos here were hand-held.
This HDF required several minutes of manual work to choose which input image to use for each area in the output image. This is done by choosing an image and "painting" with the mouse. This can take time if there are lots of adjacent near and far areas which must be painted separately using different underlying images.

This one was easy because there are no adjacent near and far areas.

Stack - Noise Suppression
9 photos were made at ISO 1600 in a darkened room with a hand-held camera. My strong computer needed 31 seconds to align and combine them into one low-noise image. This is part of a 4 megapixel image shown at full size.

Stack - Paint
The two images were taken a few seconds apart, during which time the cyclist (left image) moved out and the red car (right image, left side) moved in. The images were combined, and the car and cyclist were removed by choosing one image or the other and "painting" with the mouse.
Four photos made in quick succession.
Stack - Paint can be used to make transient objects disappear or make them appear multiple times.

Combine up to six images to make wide-angle images. Rough alignment is done with the mouse and fine alignment is automatic. All photos here were hand-held.

Indoor scene (house pet was pasted in).

3 images with poor camera handling. The final image was straightened and retouched for brightness and color.

6 photo panorama.


Photo montage. Add images and text to a background layout of arbitrary size. Images and text can be moved around using the mouse, resized, rotated, and made party or wholly transparent. Transparency can be painted gradually or fully. Text can have any font, size, and angle. Background, outline and shadow can be added to text, with adjustable color and transparency for all of these.

Magnify Image

Move around over an image with a simulated magnifying glass.
Diameter and magnification are adjustable.


Sometimes panorama images must be straightened.
Adjust while watching a live output image.

Fix Perspective

Fix images photographed from an angle, e.g. paintings, buildings, etc.
Select the 4 corners and transform into a rectangle.

Fix Barrel Distortion

RAW files can have lens distortion if the raw converter has no correction data for the camera and lens combination. This can be easily fixed using only eyeball judgement.

Flatten photo of a curved surface
Flatten the page edges and stretch the squeezed text where the page curves down at the center binding. Mark the page top and bottom edges at several points using the mouse. The rest is automatic. Use for any curved image, e.g. a poster on a round column.

Mouse Painting

Use for retouching. Pick a color from the image or from a palette. Variable brush size and transparency allow gradual change without edge effects.

Warp Image, 4 variations

Pull the image with the mouse.
The image behaves like sheet rubber.

Unwarp Close-up Photo (selfie)
Close-up portraits exhibit a "balloon face" distortion.
There is a special function just for this problem.

Improve Botticelli

Straighten her eyes and smooth her skin.

Make Mosaic Image

Make any image into a mosaic with tiles created from your images. Click on a tile to get a larger popup image which you can resize and drag. This requires that you have thousands of images in your collection, with an adequate range of available colors.

Click on image to view full size.
Make a Table of Images
Images can be mixed sizes. They are rearranged and resized as needed to make all the columns as even as possible.

You can click on any image to get a larger popup image which can be zoomed to any size, and disappears with another click.
Add Texture to an Image

Combine texture with gradients and embossing to get interesting effects.

Add Background Pattern
A background pattern can be added to an image or selected areas. The pattern is a small image that is repeated to cover a larger area. If the pattern repeats, dimensions are found automatically to make the pattern seamless (left example). The pattern can be a photo of a texture, as in the right sample. Pattern scale and opacity are adjustable.

Write Text

Write text on images. Select font, colors, transparencies, shadow, angle. Watermarks are made by writing faint text and embossing.

Lines, arrows, boxes, and circles/ovals can also be added.

Fix a Lousy Photo

The upper photo had multiple retouches to produce the one below. The functions used were trim/rotate, flatten brightness distribution, increase contrast, increase color saturation, and gradients. These were applied in different areas of the image.

The photo was back-lighted and the Fall colors came out faded. The following steps were made in sequence: select the sky, invert the selection (everything but the sky), increase overall brightness with an upward slope for more contrast, select the foreground vegetation areas, add more contrast, add color saturation, add slight gradients.
Art Effects
Convert a photo into a simulated drawing, painting, embossing, cartoon. These take a few seconds to a few minutes, depending on how long you want to play with the controls to optimize the result.







Your Veteran Coder


Fotocx is a free Linux program for editing photos or other images and managing a large collection. Fotocx has powerful editing tools to correct and enhance photos. Fotocx can instantly find desired images within a huge collection, based on folder and file names or embedded metadata such as dates, tags/keywords, titles, comments, ratings, location, camera data - any metadata.

Image folders can be viewed as a scrolling gallery of thumbnail images. Navigation of folders and subfolders is simple and fast. Click on a thumbnail for a full window view of the image. The image can be zoomed, panned and scrolled using the mouse. Gallery thumbnails can vary from small to huge. Popup windows can be used to view or compare multiple images at any scale. Thumbnail galleries are also used to display image search results and albums. Albums are selected images arranged in a desired order. Fotocx has many editing tools that go beyond the basics. Images with severe problems (underexposed, false colors, blurred, uneven lighting, fog/haze) can be brought back to life. Details lost in shadows or haze can be brought out. Images with distorted perspective (esp. wide-angle views) can be corrected.

Fotocx is standards compliant. Nothing done by Fotocx makes your images less usable with other applications. Fotocx uses your image files wherever they are: they are not moved or duplicated. Fotocx does create an index for fast image searching, and thumbnail images for fast gallery displays. These add typically 2% to overall storage requirements. There is no database to manage - the index manages itself. 

Fotocx can import RAW images and perform all processing in deep color (24 bits per color used internally). Edited images can be saved as JPEG, TIFF (8/16 bits/color), or PNG (8/16 bits). Convert single RAW files (click thumbnail) or selected batches (click thumbnails from gallery pages).

Image edit functions are interactive with rapid visual feedback, using the full image or a chosen zoom-in area. Undo and Redo can be applied serially to all the edits of an image. Intermediate and final results can be saved as new files or as versions of the input file (e.g. filename.v02.jpg).

Objects or areas within an image can be selected and edited separately from the background. Areas can be selected using several methods: drag the mouse to select and flood into matching tones, follow feature edges, or outline an area freehand. Complex feature edges, such as hair or foliage, can be accurately selected. Selected areas can be copied and pasted into the same or other images, resized, rotated, brightened, etc. Layers are not used. Each edit stage can be saved separately as a file 'version'. These can be re-used to make new versions. Prior versions or other image sources can be "mouse painted" onto areas within new versions or images - paint from any source to any destination, with simultaneous rescale if wanted.

Batch functions are available to copy, move, rename, resize, upright, convert format, convert RAW files, and add or revise metadata.

Several tools are available to change size and shape: crop, resize (rescale), rotate, fix perspective, curve/warp the whole image or selected areas within the image. There is a special tool to 'flatten' photos of curved surfaces, e.g. a page from a thick book or a poster on a round column.

Text can be added to an image. Any font and size can be used, any color, any angle. The text can have variable transparency, an outline, a shadow, or an embossed effect - good for a signature or copyright. Other basic markups are available: lines, arrows, box, oval/circle.

Dust spots from old slides or photos can be removed, roadside trash or power lines can be erased. Panoramas can be made by stitching photos together seamlessly, automatically matching brightness and color. Photos with a range of exposure values can be combined into an HDR image with adjustable contributions. Photos with varying focus depths can be combined into an image that is sharp over the combined range. Photos of one scene taken at different moments can be combined to remove passing autos or tourists. Multiple photos made under low light conditions can be combined to reduce noise. Images and text can be combined into a mashup, using the mouse to position and resize the components and adjust overlaps and transparencies.

Fotocx has a batch scripting tool to speed the processing of multiple images requiring the same edits: record the edits made to a base image and then apply these edits automatically to any number of selected images.

Many special effects ('filters') are available to convert a photo into a line drawing, sketch, painting, embossing, cartoon, dithered image, mosaic, or abstract patterns. Background patterns and textures can be added.

Images can be rapidly searched using file and folder names or partial names, dates, assigned tags, ratings, locations, and any other metadata stored in the image. Some data is automatic from the camera (date, location, exposure data), and other data can be manually entered (tags, captions ...). Batch tools are available to load metadata into many images at once. Search criteria can be used in combination; e.g. find Chicago photos for years 2002-2005 containing tags 'Barbara' or 'Barbie'.

Locations (from a camera GPS sensor or entered manually) can also be searched. You can view a map of any region in the world, at any scale, using an internet map service. Images having location data show as markers on these maps. Click a marker to get a gallery of the corresponding images. Local map files of the world, each continent, and some countries are also available, and you can add your own maps at any scale. Local maps have no dependency on the internet. You can jump from a given photo to its position on a world map, where you can find other photos from the same or nearby positions.

Albums can be made using selected images from your collection. The files are not duplicated. Select images by clicking gallery thumbnails. Arrange the images with drag and drop. Albums can be made into slide shows. Choose animated transitions between images, pan and zoom effects, and places to auto-pause for narration.

Fotocx includes a comprehensive user manual that also serves as interactive help: press F1 while using any function in Fotocx. You should take the time to read the overview pages. The function details can be viewed as needed.

Summary of Fotocx Capabilities
 • Organize and manage a very large photo/image collection.
 • Comprehensive user guide and popup context help via F1 key.
 • Thumbnail browser/navigator with variable thumb size and metadata view.
 • Click thumbnail for full-size view, image zoom in/out and pan/scroll.
 • RAW file conversion, single or batch, output with 8 or 16 bits per color.
 • Large set of functions to edit, repair, refine, and transform images.
 • Internal processing in 24 bits per color (float), output in 8 or 16 bits.
 • Edited files have a version number, originals are retained by default.
 • Fast edit visual feedback using the full image or selected zoom-in area.
 • Undo/Redo button - compare original/edited versions (instant replace).
 • Conventional edit functions: rotate, upright, crop, rescale, add margins,
    retouch: brightness/color/contrast/saturation/temperature/white balance,
    markup: text (decorative features)/lines/arrows/boxes/circles/ellipses,
    edit colors using RGB or HSL, convert B&W/color/negative/positive/sepia.
 • Repair functions: sharpen, blur selected areas, denoise, defog, red eyes,
    smart erase (remove spoilers), remove halos, suppress JPEG artifacts,
    anti-alias (suppress jaggies), remove dust spots, fix chromatic aberration.
 • Refine functions: edit or flatten brightness distribution (enhance detail),
    increase local contrast (enhance detail), match colors to master image,
    add soft focus, steepen brightness gradients, global and local retinex,
    add brightness ramp in any direction, add/remove vignette (via curve edit).
 • Special effect conversions: sketch, outlines, cartoon, emboss, painting,
    tiles, texture, pattern, dither (5 modes), engrave, mosaic, shift colors,
    add noise (hide color bands), set no. of colors (per RGB), alien colors.
 • Warp image: unbend (wide-angle photos, panoramas), warp selected area,
    fix perspective (photo from an angle), warp image (linear/curved/affine),
    unwarp closeup (fix baloon face), add waves, twist image, make sphere,
    turn inside-out, tiny planet, escher spiral, flatten curved horizon,
    flatten photo of curved surface (thick book page, poster on a column).
 • Edit functions can be 'painted' locally and gradually, using the mouse.
 • Copy areas within and across images by mouse painting and blending.
 • Create or maintain transparent image areas while editing.
 • Combine images: HDR (combine bright/dark images, adjust contributions),
    HDF (combine different focus depths), stack/layer combinations by area,
    panorama (2-6 images), make an array or matrix of many images.
 • Mashup: arrange images and text in an arbitrary layout using the mouse.
    (objects can be resized, rotated, overlapped with transparent areas ...)
 • Custom user menu: collect frequently used functions into one menu.
 • Plugins: use Gimp, Imagemagic ... as embedded Fotocx edit functions.
 • Scripts: record image edits, package as an edit function to re-use.
 • Select image objects or areas to edit separately from the background:
    outline by hand, follow feature edges, 'flood' into matching colors ...
 • Complex feature edges can be accurately selected (e.g. hair, foliage).
 • Batch tools: rename, resize, convert, export, add/revise/report metadata,
    convert RAW files, add overlay text, apply custom edit script.
 • Metadata edit and report (tags, dates, titles, geotags ... any metadata).
 • Search images using any metadata and folder/file names or partial names:
    dates, tags, locations, ratings, titles, descriptions, exposure data ...
 • Show a list of images by location and date range, click for image gallery.
 • Show an image calendar, click on year or month for a gallery of images.
 • Scalable internet map, click on marker for gallery of images at location.
 • Add location names and geocoordinates to an image by clicking on the map.
 • View 360 degree panorama image (Google Street View format).
 • Show video files as thumbnails (using any video frame), play video.
 • Show animated GIF files as thumbnails (first frame), play animation.
 • Bookmarks: assign names to folder/file locations, go to name (gallery).
 • Create albums with chosen images arranged by drag & drop. No duplication.
 • Slide show: show album images with animated transitions and pan/zoom.
 • Print an image at any scale. Printer color calibration tool is available.
 • Custom keyboard shortcuts can be assigned to chosen functions.
 • Cycle wallpaper images from a Fotocx album or any folder of image files.
 • Source and binary packages are installable on most recent Linux flavors.
 • Gnu GPL3 license (everything is free to use as you please).