Unified Video Decoder

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The Unified Video Decoder (UVD), previously called Universal Video Decoder is the video decoding unit from AMD to support hardware decode of H.264 and VC-1 video codec standards, and being a part of ATI Avivo HD technology.

Operating system support[edit]



The UVD is based on an ATI Xilleon video processor, incorporated into the same die of the GPU and part of the ATI Avivo HD for hardware decoding videos, along with the Advanced Video Processor (AVP). UVD, as stated by AMD, handles decoding of H.264/AVC, and VC-1 video codecs entirely in hardware. However, video post-processing is passed to Pixel shaders and OpenCL Kernels. MPEG-2 decoding is not performed within UVD, but in the shader processors. The decoder meets the performance and profile requirements of Blu-ray and HD DVD, decoding H.264 bitstreams up to a bitrate of 40 Mbit/s. It has context-adaptive binary arithmetic coding (CABAC) support for H.264/AVC.

Unlike video acceleration blocks in previous generation GPUs, which demanded considerable host-CPU involvement, UVD offloads the entire video-decoder process for VC-1 and H.264 except for video post-processing, which is offloaded to the shaders. MPEG-2 decode is also supported, but the bitstream/entropy decode is not performed for MPEG-2 video in hardware. Previously, neither ATI Radeon R520 series' ATI Avivo nor NVidia Geforce 7 series' PureVideo assisted front-end bitstream/entropy decompression in VC-1 and H.264 - the host CPU performed this work.[4] UVD handles VLC/CAVLC/CABAC, frequency transform, pixel prediction and inloop deblocking, but passes the post processing to the shaders.[5] Post-processing includes denoising, de-interlacing, and scaling/resizing. AMD has also stated that the UVD component being incorporated into the GPU core only occupies 4.7 mm² in area on 65 nm fabrication process node.

A variation on UVD, called UVD+, was introduced with the Radeon HD 3000 series. UVD+ support HDCP for higher resolution video streams.[6] But UVD+ was also being marketed as simply UVD.

UVD 2[edit]

The UVD saw a refresh with the release of the Radeon HD 4000 series products. The UVD 2 features full bitstream decoding of H.264/MPEG-4 AVC, VC-1, as well as iDCT level acceleration of MPEG2 video streams. Performance improvements allow dual video stream decoding and Picture-in-Picture mode. This makes UVD2 full BD-Live compliant.

UVD 2.2[edit]

The UVD 2.2 features a re-designed local memory interface and enhances the compatibility with MPEG2/H.264/VC-1 videos. However, it was marketed under the same alias as "UVD 2 Enhanced" as the "special core-logic, available in RV770 and RV730 series of GPUs, for hardware decoding of MPEG2, H.264 and VC-1 video with dual-stream decoding". The nature of UVD 2.2 being an incremental update to the UVD 2 can be accounted for this move.

UVD 3[edit]

UVD3 adds support for bitstream MPEG2 decoding, DivX and Xvid via MPEG-4 Part 2 decoding and Blu-ray 3D via MVC.[7] along with 120 Hz stereo 3D support,[8] and is optimized to utilize less CPU processing power.


Originally, ATI planned to implement the UVD in its RV550 series GPU aimed at mainstream market, with two different specifications in which one features HDMI and video out support another featuring DVI as well as video-out support, and production was in December 2006, revealed by the slides. However, as of the current date, no information is available about the release of related products. Some suggested the RV550 products were for OEMs, while some speculated the product was cancelled.

Most of the Radeon HD 2000 series video cards implement the UVD for hardware decoding of 1080p high definition contents.[9] However, the Radeon HD 2900 series video cards do not include the UVD (though it is able to provide partial functionality through the use of its shaders), which was incorrectly stated to be present on the product pages and package boxes of the add-in partners' products before the launch of the Radeon HD 2900 XT,[citation needed] either stating the card as featuring ATI Avivo HD or explicitly UVD,[citation needed] which only the former statement of ATI Avivo HD is correct. The exclusion of UVD was also confirmed by AMD officials.[10]

UVD2 is implemented in the Radeon RV7x0 and R7x0 series GPUs. This also includes the RS7x0 series used for the AMD 700 chipset series IGP motherboards.

UVD-enabled GPUs[edit]

Engineering Name Marketing Name UVD Version
Cayman Radeоn HD 6900 Series UVD 3
Barts Radeоn HD 6800 Series UVD 3
Turks Radeоn HD 6600 Series UVD 3
Sumo Radeоn HD 6500 Series UVD 3
Caicos Radeоn HD 6400 Series UVD 3
Palm Radeоn HD 6300 Series UVD 3[11]
- Radeоn HD 6200 Series UVD 3[11]
Radeоn HD 5900 Series
Radeon HD 5800 Series
UVD 2.2
Juniper Radeоn HD 5700/6700 Series UVD 2.2
Redwood Radeоn HD 5600/5500 Series UVD 2.2
Cedar Radeоn HD 5400 Series UVD 2.2
RV790 Radeon HD 4890 Series UVD 2[12]
Radeon HD 4800 X2 Series
Radeon HD 4800 Series
RV740 Radeon HD 4700 Series UVD 2.2
RV730 Radeon HD 4600 Series UVD 2.2
RV710 Radeon HD 4300/4500 Series UVD 2.2
RV670 Radeon HD 3800 Series UVD+
RV635 Radeon HD 3600 Series UVD+
RV620 Radeon HD 3400 Series UVD+
RV630 Radeon HD 2600 Series UVD
RV610 Radeon HD 2400 Series UVD
RS880 Radeon HD 4200/AMD 785G Chipset UVD 2
Radeon HD 3200/AMD 780G Chipset
Radeon HD 3300 IGP/AMD 790GX Chipset
UVD [13]
M98 Mobility Radeon HD 4800 Series UVD 2
M96 Mobility Radeon HD 4600 Series UVD 2
M92 Mobility Radeon HD 4300/4500 Series UVD 2.2
M88 Mobility Radeon HD 3800 Series UVD+
M86 Mobility Radeon HD 3600 Series UVD+
M82 Mobility Radeon HD 3400 Series UVD+
M76 Mobility Radeon HD 2600 Series UVD
M72 Mobility Radeon HD 2400 Series UVD
M71 Mobility Radeon HD 2300 Series UVD
RV550 Unknown


  • NB1: Dual-GPU variants with 2 of the latter GPUs.
  • NB2: Driver version 8.371 or later must be used if the GPU is "Mobility Radeon HD 2300" for enabling UVD functions for H.264 videos, or system may crash.

See also[edit]


  1. ^ Phoronix
  2. ^ AMD's X-Video Bitstream Acceleration
  3. ^ AMD Releases Open-Source UVD Video Support
  4. ^ (Chinese)HardSpell review
  5. ^ Smith, Ryan (February 24, 2010). "AMD’s Radeon HD 5450: The Next Step In HTPC Video Cards". AnandTech. AnandTech, Inc. p. 4. Retrieved April 7, 2010. "Since deinterlacing and other AVIVO post-processing actions are done by the shader hardware, the limited shading capabilities of these cards meant that AMD couldn’t offer the full suite of AVIVO abilities at once." 
  6. ^ (Chinese) PC-DVD discussion thread, retrieved August 23, 2008
  7. ^ http://www.dailytech.com/Radeon+6800+Series+Launches+Targets+GeForce+GTX+460/article19928.htm by Jansen Ng, 10/21/2010 DailyTech
  8. ^ "AMD A6-3650 Llano APU Review - Page 5". Hardwarecanucks.com. Retrieved 2014-04-17. 
  9. ^ HKEPC report
  10. ^ DailyTech report
  11. ^ a b [1][dead link]
  12. ^ "Google Translate". Translate.google.com. Retrieved 2014-04-17. 
  13. ^ Don Woligroski (2009-08-03). "Features For The Home-Theater Crowd - Updated: AMD 785G: The Venerable 780G, Evolved". Tomshardware.com. Retrieved 2014-04-17. 

External links[edit]