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LazPaint is an image editor with layers and transparency. It supports the format OpenRaster so it can interoperate with MyPaint, Gimp and Krita.

lazpaint preview.jpg

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The underlying graphic library BGRABitmap was started to provide advanced drawing in Free Pascal with Lazarus. In order to show the capabilities of the library, I started LazPaint. Finally it became real image editor and a source of improvement for the library BGRABitmap.


File formats: read and write a variety of file formats, including layered bitmaps and 3D files.

Selection: select parts of an image with antialiasing and modify the selection as a mask.


How to use it

Useful keys

  • Maintaining Space key down switches temporarily in move mode
  • F6 key hides/shows all tool windows
  • Ctrl key aligns to image pixels and limits possible angles with rotation tool
  • Backspace key erases last point in a polygon or last letter in a text
  • Enter key releases selection

Right mouse button can be used to:

  • Swap drawing colors temporarily
  • Subtract from selection (selection tool)
  • Define light position (shaded text, shaded shapes)
  • Finish a shape (polygon, curve)


Video tutorials are available on Youtube :


Support this project

Binaries can be downloaded on Sourceforge for Windows and Linux.

You can also download the source code and compile it for a specific platform. MacOS version is a bit experimental, to compile it, it is necessary to remove the dependency to LNet package.


Lazpaint curve redim.png


Many common actions can be done with the toolbar. Zoom can be changed with the magnifying glass (+ or -), or by clicking on the 1:1 button to show the image at its original size in pixels, or with the zoom fit button to set the zoom so that the whole image be within the window.

It is possible to undo/redo the 200 last operations. If you have a doubt on what you are drawing, undo back to the beginning, save a copy, and redo the modifications before going further.


The main window allows to draw, and there is also a color circle window and a toolbox. Use the color circle window to select a color, its luminosity and its opacity. The toolbox offers a wide range of drawing tools and selection tools.

Image manipulation

An image can be resampled, flipped horizontally and vertically.

Smart zoom x3 : resize the image x3 and detects borders; this provides a useful zoom with ancient games sprites.

Color manipulation

  • Colorize : set the color of an image while preserving intensities
  • Shift colors : cycle colors and change colorness (saturation)
  • Intensity : make colors lighter or darker without making them white
  • Lightness : make colors lighter or darker by making them whiter
  • Normalize : use the whole range of each color channel and alpha channel
  • Negative : invert colors (with gamma correction)
  • Linear negative : invert colors (without gamma correction)
  • Grayscale : converts colors to grayscale with gamma correction


Filters can be applied to the whole image or to the active selection.

  • Radial blur : non directional blur
  • Motion blur : directional blur
  • Custom blur : blur according to a mask
  • Sharpen : makes contours more accute, complementary to Smooth
  • Smooth : softens whole image, complementary to Sharpen
  • Median : computes the median of colors around each pixel, which softens corners
  • Contour : draws contours on a white background (like a pencil drawing)
  • Emboss : draws contours with shadow
  • Sphere : spherical projection
  • Cylinder : cylinder projection
  • Clouds : add clouds of the current pen color

Command line

General use :

lazpaint inputfile [/command1 [/command2...]] [outputfile]

On Linux, the command prefix is '-'. on Windows, the command prefix can be '-' or '/'.

Line without command

You can omit commands to convert an image to another file format. For example :

lazpaint image.pdn image.png

will flatten and save a Paint.NET image into a PNG.

Line without output file

If you do not specify an output file, the application is opened with the resulting image. For example:

lazpaint image.png /RotateCW

will open the image with a 90┬░ rotation.

Line without input file

You can also create an image out of nothing. For example :

lazpaint /New(800,600) /Gradient(255,255,255,255,0,0,0,255,Linear,0,0,800,600) blackwhite.png

will create an image with a black and white gradient and save it into blackwhite.png.

General commands

Here is the list of supported commands :

  • /HorizontalFlip : flips image horizontally
  • /VerticalFlip : flips image vertically
  • /SwapRedBlue : swaps red and blue channels
  • /RotateCW : rotates image clockwise
  • /RotateCCW : rotates image counterclockwise
  • /Resample(Width,Height: Integer) : resample image to Width x Height
  • /Opacity(Value: Byte) : applies a global factor to opacity
  • /Gradient(red1,green1,blue1,alpha1,red2,green2,blue2,alpha2: Byte; type; x1,y1,x2,y2: Single) : draws a gradient. Type can be Linear, Reflected, Diamond or Radial.
  • /New(Width,Height) : creates a new empty image of Width x Height

For example :

lazpaint bigimage.bmp /Resample(320,200) smallimage.png

will save a small copy of bigimage.bmp into smallimage.png

Filter commands

You can apply filters with default values. Here is the list of filter commands:

Blur filters : BlurPrecise, BlurRadial, BlurFast, BlurCorona, BlurDisk, BlurMotion, BlurCustom

Pixel filters : Sharpen, Smooth, Median, Emboss, Contour, Grayscale, Negative, LinearNegative, Normalize, SmartZoom3

Deformation filters : Sphere, Twirl, Cylinder, Plane

Rendering filters : PerlinNoise, CyclicPerlinNoise, Clouds, CustomWater, Water, Wood, WoodVertical, Plastik, MetalFloor, Camouflage, SnowPrint, Stone, RoundStone, Marble

For example :

lazpaint photo.jpg /Contour /Emboss /Normalize

will transform the image into a carved stone.

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