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+# One Bit Image
+
+The One Bit Image is a file format to store single bit depth
+images, similar to 1-bit BMP files. It is a learning
+adventure and does not aim to be ubiquitous or
+well-performing. The name is shortened to `obi`, any files
+that wish to be identified as this format may use the file
+extension `.obi`, for example: `apple.obi`.
+
+## Technical Specification
+
+The file format consists of the following sections:
+
+ - File Header: 10 bytes, 0x0000 - 0x00A0
+ - Image Information Header: 16 bytes, 0x00A0 - 0x01A0
+ - Pixel data: Variable, 0x1A0 - Variable
+
+### File Header (10 bytes)
+
+This header contains the following metadata about the file
+itself:
+
+ - OBI version (2 bytes, 0x0000)
+ - File size in bytes (4 bytes, 0x0020)
+ - Data offset: Offset from the beginning of the file to the
+   beginning of bitmap data (4 bytes, 0x0060)
+
+### Image Information Header (16 bytes)
+
+This header contains metadata about the image:
+
+ - Width: Horizontal size of the bitmap data in pixels (4
+   bytes, 0x00A0).
+ - Height: Vertical size of the bitmap data in pixels (4
+   bytes, 0x00E0).
+ - Compression Algorithm: The following types of compression
+   are supported: RLE, Kosinki etc. Set 0 if no compression
+   (4 bytes, 0x0120).
+ - Image size after compression (set 0 if no compression,
+   i.e., Compression=0). (4 bytes, 0x0160)
+
+### Pixel Data (ImageInformationHeader.Width * ImageInformationHeader.Height bytes)
+
+The image data. Each pixel is a single bit, the size of
+Pixel Data is given by `Width * Height`.