Compression Types
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| Baseline JPEG |
| Other names |
Discrete Cosine Transform, DCT, JPEG |
| Identifier(s) |
PUID:
x-cmp/11
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| Family |
|
| Description |
The JPEG compression algorithm was developed in 1990 by the Joint Photographic Experts Group of ISO and CCITT, for the transmission of colour and greyscale images. It is a lossy technique which provides best compression rates with complex 24-bit (True Colour) images. It achieves its effect by discarding image data which is imperceptible to the human eye, using a technique called Discrete Cosine Transform (DCT). It then applies Huffman encoding to achieve further compression. The JPEG specification allows users to set the degree of compression, using an abstract Quality Setting. This provides a trade-off between compression rate and image quality. It is important to note that the Quality Setting is not an absolute value, with different JPEG encoders use different scales, and that even the maximum quality setting for baseline JPEG involves some loss. JPEG compression is most commonly used in the JPEG File Interchange Format (JFIF), SPIFF and TIFF. |
| Lossiness |
Lossy |
| Released |
01 Jan 1994 |
| Withdrawn |
|
| Developed by |
 International Standards Organisation
|
| Supported by |
|
| Documentation |
ISO/IEC 10918-1: 1994, Information technology - Digital compression and coding of continuous-tone still images: Requirements and guidelines |
| Rights |
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| Note |
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Details: File format summary
: detailed report on file format 
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