标题: NVIDIA CUDA加速的VC-2候选视频编解码器[Dirac Video Codec] [打印本页] 作者: Edison 时间: 2008-5-17 23:54 标题: NVIDIA CUDA加速的VC-2候选视频编解码器[Dirac Video Codec] AbstractWith the introduction of high definition video formats (HDTV), it has become necessary to develop efficient methods and algorithms which achieve better compression rates and real-time decompression for streaming over low-bandwidth networks. In this work we focus on accelerating a modern, wavelet-based video codec, the Dirac Video Codec (DVC), by mapping most computations involved to graphics hardware. We show that these computations can be performed efficiently on modern, programmable GPUs, regarded as massively parallel co-processors through NVidia's CUDA compute paradigm. We implemented a number of widely useful CUDA computational kernels such as: overlapped block motion compensation, wavelet transforms based on the lifting scheme, and frame arithmetic. Our efficient motion compensation and frame arithmetic implementations can be used to accelerate other video codecs as well. Additionally, wavelet lifting has a wide range of applications ranging from image denoising to volume rendering. By implementing all these steps of the DVC decompressor, we achieved considerable speed-up compared to an optimized CPU implementation.
PaperA paper that explains the methods we came up with in detail has been submitted. As soon as it is accepted, the link will be put here.
Features
Large speedup in Dirac video decoding: allows for smooth, high-definition video decoding on systems that were incapable of this before
DownloadDownload the source tarball here.
Version: 4 (latest) (based on schrodinger SVN revision 512)
GITYou can always get the latest, cutting-edge version using the GIT version management system:
git clone git://diracvideo.schleef.org/git/schroedinger.gitgit checkout cudaLinks
The Dirac Specification is now essentially complete. The bitstream is deemed to be frozen except for bug fixes and constraints due to levels and profiles (to be added over time). Two versions of the specification exist: Version 1 (Dirac Pro) and Version 2 (Full Dirac).
Dirac Pro is an intra-only version of Dirac and has been proposed to the Society of Motion Picture and Television Engineers (SMPTE) for standardisation as VC-2. It's suitable for professional applications e.g. in television studios or post-production. Version 1.0 is available here:
Dirac Specification Version 1.1.0 (Dirac Pro or VC-2)
pdf
(Note that this is converted from Word 2003 as this is the SMPTE format of choice, and may have some minor conversion errors. The Word version is available here.)
The full Dirac specification has reached version 2.2 and is the same as Dirac Pro version 1 except that it also includes motion compensation so that it is suitable for distribution applications (broadcasting and streaming) also. It is available here:
Dirac Specification Version 2.2.0
pdf
In both cases, the specification covers the stream syntax, stream parsing operations and decoding processes. It specifies both the core syntax for general operation and a "low delay" syntax for professional use.作者: bigpao007 时间: 2008-5-18 00:47