imgcreate

imgcreate

imgcreate creates PNG, BMP, TGA, and JPEG images from pixels. It returns the images as strings, so it's the callers responsibility's to write it to disk. Pixels are sampled via a callback function.

Bulding

It's just one file, either add it to your project or build a loadable Lua module with:

$ gcc -std=c99 -O2 -Werror -Wall -Wpedantic -Wno-unused-function -shared -fPIC -o imgcreate.so imgcreate.c

Usage

imgcreate.png

imgcreate.png creates a PNG image. Its arguments are:

1. Width of the image
2. Height of the image
3. Number of components

• 1 for images with only the Y (brightness) component
• 2 for YA images (Y + alpha)
• 3 for RGB images (red, green, and blue)
• 4 for RGBA images (RGB + alpha)

1. The callback function used to sample pixels

• This function will be called for every pixel of the image, and must return 1 to 4 values depending on the number of components passed in the previous argument

Example:

local imgcreate = require 'imgcreate'

local png = imgcreate.png(256, 256, 3, function(x, y)
    return x, 0, y
end)

io.open('test.png', 'wb'):write(png):close()

imgcreate.bmp, imgcreate.tga and imgcreate.jpeg

These functions work exactly the same way as imgcreate.png, but generate their respective formats. imgcreate.jpeg has an additional parameter before the callback function that specifies the desired quality, between 1 and 100.

Changelog

• 1.0.0
  • First public release

License

MIT, enjoy.