Lossy Coding

Member’s Name

Usaid Syawahidul Chaq 5113100089 Muhammad Ghulam Fajri 5113100094 Hanif Sudira 5113100184

Multimedia Network Definition What is ? In information technology, lossy compression is the class of data encoding methods that uses inexact approximations or partial data discarding to represent the content. These techniques are used to reduced data size for storage, handling, and transmitting content. 1. JPEG JPEG(Joint Photographic Experts Group) is a commonly used method of lossy compression for digital images, particularly for those images produced by . The degree of compression can be adjusted, allowing a selectable tradeoff between storage size and image quality. JPEG typically achieves 10:1 compression with little perceptible loss in image quality. [citation needed]

JPEG compression is used in a number of image file formats. JPEG/ is the most common image format used by digital cameras and other photographic image capture devices; along with JPEG/JFIF, it is the most common format for storing and transmitting photographic images on the World Wide Web. [citation needed] These format variations are often not distinguished, and are simply called JPEG.

The term "JPEG" is an acronym for the Joint Photographic Experts Group, which created the standard. The MIME media type for JPEG is image/, except in older Internet Explorer versions, which provides a MIME type of image/pjpeg when uploading JPEG images.[2] JPEG files usually have a of .jpg or .jpeg.

JPEG/JFIF supports a maximum image size of 65535×65535 pixels,[3] hence up to 4 gigapixels (for an aspect ratio of 1:1).JPEG 2000 JPEG 2000 is an image coding system that uses state-of-the-art compression techniques based on wavelet technology. Its architecture lends itself to a wide range of uses from portable digital cameras through to advanced pre-press, medical imaging and other key sectors. 2. JPEG 2000 is an standard and coding system. It was created by the Joint Photographic Experts Group committee in 2000 with the intention of superseding their original discrete cosine transform-based JPEG standard (created in 1992) with a newly designed, wavelet-based method. The standardized filename extension is .jp2 for ISO/IEC 15444-1 conforming files and .jpx for the extended part-2 specifications, published as ISO/IEC 15444-2. The registered MIME types are defined in RFC 3745. For ISO/IEC 15444-1 it is image/jp2.

JPEG 2000 code streams are regions of interest that offer several mechanisms to support spatial random access or region of interest access at varying degrees of granularity. It is possible to store different parts of the same picture using different quality. 3. WebP WebP is a new image format that provides lossless and lossy compression for images on the web. WebP lossless images are 26% smaller in size compared to PNGs. WebP lossy images are 25-34% smaller in size compared to JPEG images at equivalent SSIM index. WebP supports lossless (also known as alpha channel) with just 22% additional bytes. Transparency is also supported with lossy compression and typically provides 3x smaller file sizes compared to PNG when lossy compression is acceptable for the red/green/blue color channels. 4. PCM Pulse-code modulation (PCM) is a method used to digitally represent sampled analog signals. It is the standard form of digital audio in computers, Compact Discs, digital telephony and other digital audio applications. In a PCM stream, the amplitude of the analog signal is sampled regularly at uniform intervals, and each sample is quantized to the nearest value within a range of digital steps. 5. LPCM Linear pulse-code modulation (LPCM) is a specific type of PCM where the quantization levels are linearly uniform.[5] This is in contrast to PCM encodings where quantization levels vary as a function of amplitude (as with the A-law algorithm or the μ-law algorithm). Though PCM is a more general term, it is often used to describe data encoded as LPCM. 6. TIFF TIFF (Tag Image ) is a common format for exchanging () images between application programs, including those used for scanner images. A TIFF file can be identified as a file with a "." or ".tif" file name suffix. The TIFF format was developed in 1986 by an industry committee chaired by the Aldus Corporation (now part of Adobe Software). Microsoft and Hewlett-Packard were among the contributors to the format. One of the most common graphic image formats, TIFF files are commonly used in desktop publishing, faxing, 3-D applications, and medical imaging applications.