https://github.com/oppiliappan/obi

the 1-bit image format
https://github.com/oppiliappan/obi

Last synced: 2 months ago
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the 1-bit image format

• Host: GitHub
• URL: https://github.com/oppiliappan/obi
• Owner: oppiliappan
• License: mit
• Created: 2021-03-27T07:51:59.000Z (almost 4 years ago)
• Default Branch: master
• Last Pushed: 2021-04-23T11:47:09.000Z (over 3 years ago)
• Last Synced: 2024-10-10T23:41:15.725Z (3 months ago)
• Language: Rust
• Size: 38.1 KB
• Stars: 12
• Watchers: 3
• Forks: 1
• Open Issues: 0
• Metadata Files:
  • Readme: readme.md
  • License: LICENSE

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README

        
# 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`.