H.265 or NGVC (Next-generation Video Coding) is a hypothetical future ITU-T recommendation for video compression coding under study for potential development by the ITU-T Video Coding Experts Group (VCEG). The study of potential technology advances which will enable creation of H.265 is a major part of the current work of VCEG.
H.265 was initially foreseen as an entirely new standard and not an extension of H.264 like HVC by the ISO/IEC Moving Picture Experts Group (MPEG). Although some agreements about the goals of an H.265 project have been reached, e.g. computational efficiency and high compression performance,[1][2] the current state of technology does not yet seem mature for creation of an entirely new H.265 standard, and all contributions are modifications to KTA JM11, a reference H.264 encoder by the MPEG/VCEG Joint Video Team. In April 2009, the scope of the project was changed to NGVC, with a H.264+ standard being the most likely outcome; in July 2009, a joint meeting of MPEG and VCEG discussed future collaboration on NGVC and HVC, similar to the Joint Video Team effort.
The preliminary requirements for NGVC are bit rate reduction of 50% at the same subjective image quality and computational complexity comparing to H.264 High profile, with computational complexity ranging from 1/2 to 3 times as that of H.264. NGVC should be able to provide 25% bit rate reduction along with 50% reduction in complexity at the same perceived video quality as H.264 High profile.
Contents |
Features
Many new features are proposed to meet the requirements:
- 2-D non-separable adaptive interpolation filter (AIF)
- Separable AIF
- Directional AIF
- Motion compensation with 1/8-pel motion vectors
- Adaptive prediction error coding (APEC) in spatial and frequency domain
- Adaptive quantization matrix selection (AQMS)
- Competition-based scheme for motion vector selection and coding
- Mode-dependent transform customization for intra coding
It is speculated that these techniques are most beneficial with multi-pass encoding.[3]
See also
References
External links
- Draft meeting report for 31st VCEG Meeting (Marrakech, MA, 15–16 January 2007)
- Video Coding Experts Group (VCEG)
- H265.net
|
|||||||||||||||||||||||||||||||||||||||||||
This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)
