This is documentation of an archived release.
For documentation on the current version, please check Knowledge Base.

Orbit Image File

OIF stands for Orbit Image File and is a native file format developed by Orbit GT for storing images. OIF does not support multiresolution.


OIF can manage single-band raster images, black & white images, and standard RGB or 3-band images.

Reasons to use

  • OIF is native to Orbit GT and stores image data in binary format (serialization) and optimized for fast reading and visualization.
  • OIF is also neutral to images types and platform independent and can be shared among Windows, Linux and Mac.

Create and Update

An OIF can be created via the Tools 2D and 3D :

  • Convert Data : Convert one on one, one Image to one OIF (or other image storage file format)

Options and Compression

OIF uses either lossy or lossless compression: for every individual tile OIF determinates the most effective compression method.

When creating an OIF, flowing options are available to define storage and compression.

Define the number of bits (1, 8, 24 or 32) to be used to store one pixel of (raster or image) resource 1)

Bits/Sample Samples/Pixel Bits/Pixel Image type
1 1 1 Monochrome black-white
8 1 8 Grayscale
8 3 24 RGB (red green blue)
8 4 32 ARGB (alpha/transparency RGB)

Pixelsize 1

A pixel can hold one sample with 2 possible values 0 (black) or 1 (white).

When using pixelsize 1, it will be possible to set a threshold : Light, Medium or Dark.
Applying a threshold is a method to simplify an image to sets of pixels with corresponding values. The result is an image containing contiguous regions of the same value. This technique makes it easier to apply analysis.

  • Light will favor light color values.
  • Dark will aggregate dark color values.

Pixelsize 24

A pixel can hold 3 samples with a value between 0 .. 255.
Using pixelsize 24 enables extra quality parameters. :

  • Lossless “fully recoverable”, no compression
  • Lossy “with losses to quality”
    • Smallest file
    • Standard
    • Quality

Lossy meaning “with losses to quality”. Approximate sample values will be stored with sample value compression rate 5:1 up to 20:1
Examples .jpg, .ecw, .sid

Lossless always returns the original data. Lossless meaning “fully recoverable”. The exact sample values will be stored.
Examples : .gif, .png, .bmp

It is advised to save images with a wide variety of colors (photos) with lossy compression (jpg).
Images with a limited variety (computer graphics, icons) should be saved lossless (png).

Pixelsize 8 and 32 have no extra format options.

Legend and Georeference

Optionally an OMI can be accompanied by an Orbit Legend and Orbit Resource Descriptor in Orbit. OIF contains georeference information in its header.

Do not use OIF for multiresolution images or huge file sizes. Use OMI instead.
Raster / Image resources : Spatial information stored as numeric values (samples) organized in a cell matrix or grid (pixels), These pixel values represent a color. Each pixel has one or more samples (e.g. red, green and blue).
Last modified:: 2019/03/25 11:36