H.262/MPEG-2 Part 2
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H.262[1] or MPEG-2 Part 2 (formally known as ISO/IEC 13818-2[2], also known as MPEG-2 Video) is a digital video compression and encoding standard developed and maintained jointly by ITU-T Video Coding Experts Group (VCEG) and ISO/IEC Moving Picture Experts Group (MPEG). It is the second part of the ISO/IEC MPEG-2 standard. The ITU-T Recommendation H.262 and ISO/IEC 13818-2 documents are identical. The standard is available for a fee from the ITU-T[1] and ISO.
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[edit] Overview
MPEG-2 Video is similar to MPEG-1, but also provides support for interlaced video (the format used by analog broadcast TV systems). MPEG-2 video is not optimized for low bit-rates (less than 1 Mbit/s), but outperforms MPEG-1 at 3 Mbit/s and above. All standards-conforming MPEG-2 Video decoders are fully capable of playing back MPEG-1 Video streams.[3]
[edit] History
The ISO/IEC approval process was completed in November 1994.[4] The first edition was approved in July 1995[5] and published by ITU-T[1] and ISO/IEC in 1996.[6].
In 1996 it was extended by two amendments to include the Registration of Copyright Identifiers and the 4:2:2 Profile.[7][1] ITU-T published these amendments in 1996 and ISO in 1997.[6]
There are also other amendments published later by ITU-T and ISO.[1][2][8]
[edit] Editions
Edition | Release date | Latest amendment | ISO/IEC standard | ITU-T Recommendation | Description |
---|---|---|---|---|---|
First edition | 1995 | 2000 | ISO/IEC 13818-2:1996[6] | H.262 (07/95) | |
Second edition | 2000 | 2009[1][2][9] | ISO/IEC 13818-2:2000[2] | H.262 (02/00) |
[edit] Profiles and Levels
Abbr. | Name | Frames | YCbCr | Streams | Comment |
---|---|---|---|---|---|
SP | Simple Profile | P, I | 4:2:0 | 1 | no interlacing |
MP | Main Profile | P, I, B | 4:2:0 | 1 | |
422P | 4:2:2 Profile | P, I, B | 4:2:2 | 1 | |
SNR | SNR Scalable Profile | P, I, B | 4:2:0 | 1-2 | SNR: Signal to Noise Ratio |
SP | Spatial Scalable Profile | P, I, B | 4:2:0 | 1-3 | low, normal and high quality decoding |
HP | High Profile | P, I, B | 4:2:2 | 1-3 |
Abbr. | Name | Pixel/line | Lines | Framerate (Hz) | Bitrate (Mbit/s) |
---|---|---|---|---|---|
LL | Low Level | 352 | 288 | 30 | 4 |
ML | Main Level | 720 | 576 | 30 | 15 |
H-14 | High 1440 | 1440 | 1152 | 30 | 60 |
HL | High Level | 1920 | 1152 | 30 | 80 |
Profile @ Level | Resolution (px) | Framerate max. (Hz) | Sampling | Bitrate (Mbit/s) | Example Application |
---|---|---|---|---|---|
SP@LL | 176 × 144 | 15 | 4:2:0 | 0.096 | Wireless handsets |
SP@ML | 352 × 288 | 15 | 4:2:0 | 0.384 | PDAs |
320 × 240 | 24 | ||||
MP@LL | 352 × 288 | 30 | 4:2:0 | 4 | Set-top boxes (STB) |
MP@ML | 720 × 480 | 30 | 4:2:0 | 15 (DVD: 9.8) | DVD, SD-DVB |
720 × 576 | 25 | ||||
MP@H-14 | 1440 × 1080 | 30 | 4:2:0 | 60 (HDV: 25) | HDV |
1280 × 720 | 30 | ||||
MP@HL | 1920 × 1080 | 30 | 4:2:0 | 80 | ATSC 1080i, 720p60, HD-DVB (HDTV).
(Bitrate for terrestrial transmission is limited to 19.39Mbit/s) |
1280 × 720 | 60 | ||||
422P@LL | 4:2:2 | ||||
422P@ML | 720 × 480 | 30 | 4:2:2 | 50 | Sony IMX using I-frame only, Broadcast "contribution" video (I&P only) |
720 × 576 | 25 | ||||
422P@H-14 | 1440 × 1080 | 30 | 4:2:2 | 80 | Potential future MPEG-2-based HD products from Sony and Panasonic |
1280 × 720 | 60 | ||||
422P@HL | 1920 × 1080 | 30 | 4:2:2 | 300 | Potential future MPEG-2-based HD products from Panasonic |
1280 × 720 | 60 |
[edit] Applications
[edit] DVD
The DVD standard uses MPEG-2 video, but imposes some restrictions:
- Allowed Resolutions
- 720 × 480, 704 × 480, 352 × 480, 352 × 240 pixel (NTSC)
- 720 × 576, 704 × 576, 352 × 576, 352 × 288 pixel (PAL)
- Allowed Aspect ratio (image) (Display AR)
- 4:3
- 16:9
- (1.85:1 and 2.35:1, among others, are often listed as valid DVD aspect ratios, but are actually just a 16:9 image with the top and bottom of the frame masked in black)
- Allowed Frame rates
- 29.97 frame/s (NTSC)
- 25 frame/s (PAL)
- 23.976 frame/s through use of 3:2 pulldown (FILM)
- Audio+video bitrate
- Video peak 9.8 Mbit/s
- Total peak 10.08 Mbit/s
- Minimum 300 kbit/s
- Y'CbCr 4:2:0
- GOP structure
- Sequence header must be present at the beginning of every GOP
- Maximum frames per GOP: 18 (NTSC) / 15 (PAL), i.e. 0.6 seconds both
- Closed GOP required for multiple-angle DVDs
[edit] HD DVD & Blu-ray
The HD DVD and Blu-ray Standards use MPEG-2 video along with MPEG-4 H.264/AVC and VC1 video standards.[citation needed]
[edit] References
- ^ a b c d e f "H.262 : Information technology - Generic coding of moving pictures and associated audio information: Video". ITU-T Website. International Telecommunication Union - Telecommunication Standardization Sector (ITU-T). February 2000. http://www.itu.int/rec/T-REC-H.262. Retrieved 13 August 2009.
- ^ a b c d ISO. "ISO/IEC 13818-2:2000 - Information technology -- Generic coding of moving pictures and associated audio information: Video". ISO. http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=31539. Retrieved 31 October 2009.
- ^ Jens-Rainer Ohm (2005-07). "Introduction to MPEG-2 Video (13818-2)". http://mpeg.chiariglione.org/technologies/mpeg-2/mp02-vid/index.htm. Retrieved 1 November 2009.
- ^ P.N. Tudor (2005-12). "MPEG-2 Video compression". http://www.bbc.co.uk/rd/pubs/papers/paper_14/paper_14.shtml. Retrieved 1 November 2009.
- ^ (PDF) H.262 (07/95) Information Technology – Generic Coding of Moving Picture and Associated Audio Information: Video, ITU, http://www.itu.int/rec/dologin_pub.asp?lang=e&id=T-REC-H.262-199507-S!!PDF-E&type=items, retrieved 3 November 2009
- ^ a b c ISO. "ISO/IEC 13818-2:1996 - Information technology -- Generic coding of moving pictures and associated audio information: Video". ISO. http://www.iso.org/iso/iso_catalogue/catalogue_ics/catalogue_detail_ics.htm?csnumber=22990. Retrieved 31 October 2009.
- ^ Leonardo Chiariglione - Convenor (2000-10). "Short MPEG-2 description". http://mpeg.chiariglione.org/standards/mpeg-2/mpeg-2.htm. Retrieved 1 November 2009.
- ^ a b MPEG. "MPEG standards - Full list of standards developed or under development". chiariglione.org. http://mpeg.chiariglione.org/standards.htm. Retrieved 31 October 2009.
- ^ ISO. "ISO/IEC 13818-2:2000/Amd 3 - New level for 1080@50p/60p". http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=51746. Retrieved 2 November 2009.
[edit] External links
- Official MPEG web site
- MPEG-2 Video Encoding (H.262) - The Library of Congress
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