You’ll find in this page information about how to configure DarkFlow to get the most of it. Make sure to check at least the resources and path preferences in order to prevent from falling into nasty traps.

Resources preferences

This settings tab tells Darkflow how and how much of your computer resources it will be allowed to use.

Resources preferences

Memory managment

DarkFlow uses ImageMagick as a backing store for pixels. Here are the parameters of the ImageMagick architecture. For a detailed explanation, take a look at the ImageMagick: Architecture page.

Highly recommanded values are indicated in the corresponding tables.


Maximum area in bytes of any one image that can reside in the pixel cache memory. If this limit is exceeded, the image is automagically cached to disk and optionally memory-mapped.

32-bit 64-bit unit
1 1 GiB


Maximum amount of memory in bytes to allocate for the pixel cache from the heap.

32-bit 64-bit unit
0 0 GiB


Maximum amount of memory map in bytes to allocate for the pixel cache.

32-bit 64-bit unit
0 2 times your RAM, or more GiB


Maximum amount of disk space in bytes permitted for use by the pixel cache. If this limit is exceeded, the pixel cache is not created and a fatal exception is thrown.

32-bit and 64-bit unit
The more, the better, but not less than the Map parameter GiB

The Disk parameters includes the quantity set with the Map parameter, hence should be the greater of both.

The difference between both parameter is the data access method:

  • Map uses virtual memory and let the operating system manage data freshness on the behalf of the application. This access method permits parallelism in the image processing.
  • Disk uses conventionnal file access to read and write image data to disk and will benefit of the buffer cache of your operating system. This access method does not permit parallelism in the image processing.
Memory and Map parameters on 32-bit systems

Be aware of that Darkflow will consume all the memory you permit the use and it will exhaust the address space of your 32-bit system pretty quickly. So, it is important to set these parameters to 0!

Memory parameter on 64-bit systems

Note that even on 64-bit systems, this parameter should be set to 0 because of the ImageMagick architecture that doesn't recycle memory used by already allocated images for newer instances. And keeping images stuck in memory is not really what you want. A better usage of this memory is to let your operating system manage it by setting the Map parameter to a higher value

Prefer the Map parameter

In order to not waste memory and to have good parallelism in the image processing



This is the number of operators allowed to run in parallel will playing the whole process. Operators are connected to each others and form some sort of dependency graph.

A safe default is 1. If your system has plenty of bandwidth you may increase this parameter to 2. A greater value may not give better performances.

ImageMagick Threads

This is the maximum number of threads that are permitted to run in parallel within the ImageMagick builtin operations.

Should be set to the number of cores of your system, or the double if hyperthreading is enabled

Do not exceed the default number of threads

There is a limitation in the way ImageMagick handles threading and DarkFlow will die stupidly if the thread number exceed the number of cores in your system.

DarkFlow Threads

This is the maximum number of threads that are permitted to run in parallel within the DarkFlow builtin operations.

Should be set to the number of cores of your system, or the double if hyperthreading is enabled

Pixels preferences

This settings tab is related to various pixels settings. Default values are OK in most cases.

Pixels preferences

Display target

This parameter sets the default rendering transfer function of the colors of linear space images. This is used by the Visualization window to set the initial value when and is used for all but non-linear pixel formats. It only affects on screen display and it does not affect how images are processed. The default sRGB value is probably what you what here and will render images in concordance with your perception of light.

Incompatible scale

Some operators do not support (HDR color scaling)[/docs/philosophy.en/#hdr] and this parameter define the behavior of operator when facing an incompatible color scale.

  • Ignore and convert the operator will convert silently the color scale of the image to something that it can handle.
  • Warning and convert the operator will convert the color scale of the image to something that it can handle and it will issue a warning message in the console.
  • Error the operator will refuse to process the image and it will issue an error message in the console. It will also mark the Image as being in error.

Lab selection size

This parameter is used by the CIE LAB color selector. It defines the width and the height of the color gamut view. The greater, the slower to interact with.

The CIE LAB color selector is used by the Selective Lab Filter

Path preferences

Path preferences

Base Directory

This directory defines the default place in your computer from where DarkFlow starts when the project does not define a base directory.

Keep things all together

Give DarkFlow a default base folder, then create sub directories in this base folder for each project. And finally create sub directories within the project for your lights, darks, flats and artifacts photos. This will permit you to move your projects from a computer to another without pain

Temporary Directory

DarkFlow will use this directory to store transcient files. These files are actual pixels stored to vacate the memory of your computer. The amount per instance of DarkFlow will not exceed the Disk parameter.

Keep an eye on the temporary directory

You may want to put this directory within the base folder to check from time to time if leaks occured. In this case you can remove all the magick-* (only if DarkFlow is not running).

Logging preferences

This settings tab defines how DarkFlow logs messages and when the messages console is raised.

Logging preferences

Log Level

This parameter permit to select the type of messages which are logged into the console. Debug being the more verbose option.

Raise console on

This parameter tells DarkFlow to raise the console in the event of a message with a priority higher or equal to the value defined with this option.

Trap on (debug)

For developers only. This permit to set break points in the code when a message of a certain class is issued. DarkFlow must run within a debugger, otherwise it will die abruptly.

Style preferences

Want to change the appearence of DarkFlow? Here you can tune the colors of the interface and the workspace.

Style preferences

Workspace only

If this option is checked, the color theme will only be applied on the workspace. All other components of the program will inherit there style from the system.


Color theme is defined with Hex triplets, the same as used through the web and defined with the #RRGGBB syntax. Three-digit shorthand triplets like #RGB may be used.