MPEG-4 Part 2, MPEG-4 Visual (formally ISO/IEC 14496-2) is a video encoding specification designed by the Moving Picture Experts Group (MPEG). It belongs to the MPEG-4 ISO/IEC family of encoders. It uses block-wise motion compensation and a discrete cosine transform (DCT), similar to previous encoders such as MPEG-1 Part 2 and H.262/MPEG-2 Part 2.

Examples of popular implementations of the encoder specifications include DivX, Xvid and Nero Digital.

MPEG-4 Part 2 is H.263 compatible in the sense that a basic H.263 bitstream is correctly decoded by an MPEG-4 Video decoder. (MPEG-4 Video decoder is natively capable of decoding a basic form of H.263.) In MPEG-4 Visual, there are two types of video object layers: the video object layer that provides full MPEG-4 functionality, and a reduced functionality video object layer, the video object layer with short headers (which provides bitstream compatibility with base-line H.263). MPEG-4 Part 2 is partially based on ITU-T H.263. The first MPEG-4 Video Verification Model (simulation and test model) used ITU-T H.263 coding tools together with shape coding.

History

The MPEG-4 Visual format was developed by the Moving Picture Experts Group (MPEG) committee.

|-

! Edition

! Release date

! Latest amendment

! Standard

! Description

|-

| First edition

| 1999

| 2000

| ISO/IEC 14496-2:1999

|

|-

| Second edition

| 2001

| 2003

| ISO/IEC 14496-2:2001

|

|-

| Third edition

| 2004

| 2009 SStP allows for up to 12-bit bit depth and up to 4:4:4 chroma subsampling, SStP is used by HDCAM SR. One patent related to this technology remains active in Brazil, which is owned by Siemens. The following organizations held patents for MPEG-4 Visual technology, as listed in the patent pool administered by MPEG-LA and later by Via-LA.

<section begin="MP4 patents" />

{| class="wikitable sortable"

! Organization

! Patents

|-

| Mitsubishi Electric

| 255

|-

| Hitachi

| 206

|-

| Panasonic

| 200

|-

| Sun Patent Trust

| 125

|-

| Toshiba

| 96

|-

| Samsung Electronics

| 92

|-

| Sony

| 84

|-

| Philips

| 73

|-

| Sharp Corporation

| 44

|-

| Pantech

| 36

|-

| Robert Bosch GmbH

| 27

|-

| Nippon Telegraph and Telephone

| 24

|-

| GE Technology Development

| 23

|-

| CIF Licensing

| 20

|-

| Dolby

| 19

|-

| Telenor

| 19

|-

| Siemens AG

| 15

|-

| JVC Kenwood

| 14

|-

| Orange S.A.

| 14

|-

| LG Electronics

| 13

|-

| Fujitsu

| 11

|-

| ZTE

| 10

|-

| Google

| 9

|-

| BT Group

| 3

|-

| Calmare Therapeutics

| 2

|-

| Cable Television Laboratories, Inc.

| 1

|-

| Canon Inc.

| 1

|-

| KDDI

| 1

|-

| Microsoft

| 1

|-

| Oki Electric Industry

| 1

|-

| Sanyo

| 1

|} <section end="MP4 patents"/>

Criticisms

MPEG-4 Part 2 has drawn some industry criticism. FFmpeg's maintainer Michael Niedermayer has criticised MPEG-4 for lacking an in-loop deblocking filter, GMC being too computationally intensive, and OBMC being defined but not allowed in any profiles among other things. Microsoft's Ben Waggoner states "Microsoft (well before my time) went down the codec standard route before with MPEG-4 part 2, which turns out to be a profound disappointment across the industry - it didn't offer that much of a compression advantage over MPEG-2, and the protracted license agreement discussions scared off a lot of adoption. I was involved in many digital media projects that wouldn't even touch MPEG-4 in the late 1990s to early 2000s because there was going to be a 'content fee' that hadn't been fully defined yet."

  • 3ivx
  • DivX
  • HDX4
  • libavcodec
  • Nero Digital
  • QuickTime
  • Xvid

See also

  • High Efficiency Video Coding
  • Advanced Video Coding
  • Quantization (image processing)
  • FourCC
  • MP3
  • ISO/IEC JTC 1/SC 29

Notes

  • MPEG-4 Part 2: Visual
  • Official MPEG web site
  • MPEG-4 Visual Patent List (MPEG LA)