Unified Video Decoder

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Unified Video Decoder (UVD), previously called Universal Video Decoder, is the AMD's hardware SIP core that performs video decoding. UVD is integrated into some of the AMD GPUs and APUs, and it supports hardware decoding of H.264 and VC-1 video codec standards. UVD occupies a considerable amount of the die surface[1] and is not to be confused with AMD's Video Codec Engine (VCE).

Operating system support[edit]

The UVD SIP core needs to be supported by the device driver, which provides one or more interfaces such as VDPAU, VAAPI or DXVA. One of these interfaces is then used by end-user software, for example VLC media player or GStreamer, to access the UVD hardware and make use of it.

AMD Catalyst, AMD's proprietary graphics device driver that supports UVD, is available for Microsoft Windows and some Linux distributions. Additionally, a free device driver is available, which also supports the UVD hardware.


Linux support for the UVD ASIC is provided by the Linux kernel device driver amdgpu.[2]

Support for UVD has been available in AMD's proprietary driver Catalyst version 8.10 since October 2008 through X-Video Motion Compensation (XvMC) or X-Video Bitstream Acceleration (XvBA).[3][4] Since April 2013,[5] UVD is supported by the free and open-source "radeon" device driver through Video Decode and Presentation API for Unix (VDPAU). An implementation of VDPAU is available as Gallium3D state tracker in Mesa 3D.

On 28 June 2014, Phoronix published some benchmarks on using Unified Video Decoder through the VDPAU interface running MPlayer on Ubuntu 14.04 with version 10.3-testing of Mesa 3D.[6]


Windows supported UVD since it was launched. UVD currently only supports DXVA (DirectX Video Acceleration) API specification for the Microsoft Windows and Xbox 360 platforms to allow video decoding to be hardware accelerated, thus the media player software also has to support DXVA to be able to utilize UVD hardware acceleration.


Support for running custom FreeRTOS-based firmware on the Radeon HD 2400's UVD core (based on an Xtensa CPU), interfaced with a STM32 ARM-based board via I2C, was attempted as of January 2012.[7]



The UVD is based on an ATI Xilleon video processor, incorporated into the same die as the GPU and part of the ATI Avivo HD for hardware video decoding, 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. The UVD technology is based on Xtensa processor from Tensilica, Inc. (later Cadence Design Systems, Inc.),[8][9][10] which was originally licensed by ATI Technologies Inc. in 2004.[11] 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.[12] UVD handles VLC/CAVLC/CABAC, frequency transform, pixel prediction and inloop deblocking, but passes the post processing to the shaders.[13] 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.[14] 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.

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]

UVD 3 adds support for additional hardware MPEG2 decoding (entropy decode), DivX and Xvid via MPEG-4 Part 2 decoding (entropy decode, inverse transform, motion compensation) and Blu-ray 3D via MVC (entropy decode, inverse transform, motion compensation, in-loop deblocking).[15][16] along with 120 Hz stereo 3D support,[17] and is optimized to utilize less CPU processing power.

UVD 3 also adds support for Blu-ray 3D stereoscopic displays.[citation needed]

UVD 4[edit]

UVD 4 includes improved frame interpolation with H.264 decoder.[18] UVD 4.2 was introduced with the AMD Radeon Rx 200 series and Kaveri APU.[citation needed]

UVD 5[edit]

UVD 5 was introduced with the AMD Radeon R9 285.[citation needed]


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.[19] 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.[20]

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.

Feature overview[edit]

The entire AMD Accelerated Processing Unit lines and some of their features
Brand Brazos
(low power)
Llano Trinity & Richland Kabini & Temash
(low power)
Kaveri Beema & Mullins
(low power)
Carrizo Carrizo-L
(low power)
Released Jan 2011 Aug 2011 Oct 2012 May 2013 Jan 2014 Q2 2014 2015 2015
Fab (nm) TSMC 40 nm GlobalFoundries 32 nm SOI 28 28 28 TBA TBA
Socket Socket FT1 Socket FM1
Socket FS1
Socket FM2
Socket FS1r2
Socket FP2
Socket AM1
Socket FT3
Socket FM2+
Socket FP3
Socket FT3b TBA TBA
CPU cores Bobcat K10 Piledriver Jaguar Steamroller Puma Excavator Puma+[21]
3D engine block "Cedar" (VLIW5) "Northern Islands" (VLIW4) "Sea Islands" "Volcanic Islands"
FYI TeraScale Graphics Core Next (Mantle, HSA)
Unified shader model
Unified Video Decoder UVD 3 UVD 4 UVD 4.2 TBA TBA
Video Codec Engine N/A VCE 1.0 VCE 2.0 TBA TBA
TrueAudio N/A Yes[22] N/A[23] TBA TBA
Max. № of displays1 2 2–3 2–4 2 2–4 2–_ TBA TBA
Linux DRM/KMS driver[24][25] Yes WiP[26] WiP[27]
Mesa 3D driver[25] Yes N/A N/A
AMD Catalyst Yes N/A N/A
  • 1 maximum of two non-DisplayPort monitors, and a maximum of second number of DisplayPort monitors, but maximum of six!

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 6500/6600/7500/7600 Series UVD 3
Sumo Radeоn HD 6500 Series UVD 3
Caicos Radeоn HD 6400 Series UVD 3
Palm Radeоn HD 6300 Series UVD 3[28]
- Radeоn HD 6200 Series UVD 3[28]
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 2.1[29]
Radeon HD 4800 X2 Series
Radeon HD 4800 Series
UVD 2.1[29]
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 2.0[29]
Radeon HD 3200/AMD 780G Chipset
Radeon HD 3300 IGP/AMD 790GX Chipset
UVD 2.0[29]
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. ^ "AMD A-Series APU block diagram". 2011-06-30. Retrieved 2015-01-22. 
  2. ^ Michael Larabel (October 8, 2014). "The Slides Announcing The New "AMDGPU" Kernel Driver". Phoronix. Retrieved January 22, 2015. 
  3. ^ "UVD Is Enabled For Linux In Catalyst 8.10". Phoronix. 2008-10-15. Retrieved 2015-01-22. 
  4. ^ "AMD's X-Video Bitstream Acceleration". Phoronix. 2008-10-28. Retrieved 2015-01-22. 
  5. ^ "AMD Releases Open-Source UVD Video Support". Phoronix. 2013-04-02. Retrieved 2015-01-22. 
  6. ^ "AMD Radeon VDPAU Video Performance With Gallium3D". Phoronix. 2014-06-28. Retrieved 2015-01-22. 
  7. ^ "Interfacing a PC graphics card (Radeon HD 2400) with a STM32 microcontroller". Edaboard.com. 2012-01-09. Retrieved 2014-04-27. 
  8. ^ Cheung, Ken (2009-01-08). "Consumer Electronics Show Features Tensilica-enabled Products". EDA Geek. Retrieved 2014-05-15. 
  9. ^ "Customer Profiles | Cadence IP". Ip.cadence.com. 2014-04-13. Retrieved 2014-05-15. 
  10. ^ "Tensilica News: Excellent AMD ATI Video with Xtensa". tensilica.com. 2009-10-05. Retrieved 2014-05-15. 
  11. ^ "ATI Licenses Tensilica's Xtensa Configurable Processor". Business Wire. 2004-10-18. Retrieved 2014-05-15. 
  12. ^ (Chinese)HardSpell review
  13. ^ 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. 
  14. ^ (Chinese) PC-DVD discussion thread, retrieved August 23, 2008
  15. ^ White Paper | AMD Unified Video Decoder (UVD)
  16. ^ http://www.dailytech.com/Radeon+6800+Series+Launches+Targets+GeForce+GTX+460/article19928.htm by Jansen Ng, 10/21/2010 DailyTech
  17. ^ "AMD A6-3650 Llano APU Review - Page 5". Hardwarecanucks.com. Retrieved 2014-04-17. 
  18. ^ AMD A10-7850K 'Kaveri' review: AMD's new APU
  19. ^ HKEPC report
  20. ^ DailyTech report
  21. ^ "2015 AMD Mobile Roadmap adds “Carrizo” and “Carrizo-L” SoCs to APU ​". 
  22. ^ "A technical look at AMD’s Kaveri architecture". Semi Accurate. Retrieved 6 July 2014. 
  23. ^ "Mullins and Beema do not support HSA nor TrueAudio". 
  24. ^ Airlie, David (2009-11-26). "DisplayPort supported by KMS driver mainlined into Linux kernel 2.6.33". Retrieved 2014-07-02. 
  25. ^ a b "Radeon feature matrix". freedesktop.org. 
  26. ^ "AMDKFD Driver Does More Prepping For Carrizo / VI APUs". 2015-01-13. Retrieved 2015-01-13. 
  27. ^ "AMDKFD Driver Does More Prepping For Carrizo / VI APUs". 2015-01-13. Retrieved 2015-01-13. 
  28. ^ a b [1][dead link]
  29. ^ a b c d "Phoronix.com Forum". phoronix.com. Retrieved 2014-08-26. 

External links[edit]