MPEG-2 Part 2

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MPEG-2 Part-2 (formally, ISO/IEC 13818-2) or H.262, is a video compression standard developed in a joint partnership between the ITU-T and the ISO/IEC Moving Picture Experts Group organizations. It was approved in 1994 but in 1996 it was extended and was added another profile.

Contents

[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.

[edit] Features

[edit] Profiles and Levels

MPEG-2 Profiles
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
MPEG-2 Levels
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 Standarts use mpeg-2 video along with H.264/AVC and VC1 video standards.