Image Compression

Joint Photographic Experts Group (JPEG)

JPEG is a compressed image.

Resources

• https://www.imaging.org/IST/IST/Resources/Tutorials/Inside_JPEG.aspx

The JPEG compression algorithm is a widely used method for reducing the size of images, which makes them easier to store and share.

The JPEG image compression technique consists of 5 functional stages. They are

1. an RGB to YCC color space conversion
2. a spatial subsampling of the chrominance channels in YCC space,
3. the transformation of a blocked representation of the YCC spatial image data to a frequency domain representation using the discrete cosine transform,
4. a quantization of the blocked frequency domain data according to a user-defined quality factor, and finally
5. the coding of the frequency domain data, for storage, using Huffman coding.