编辑“︁DxVA”︁（章节）

==功能==
硬件上支援DXVA规范的显卡芯片，并不代表实现了DXVA的所有功能。DXVA制定硬件加速解码可分四级：
*VLD：控制BitStream
*IDCT（反餘弦變換）：IDCT级别的解码包含MoComp和PostProc
*MoComp，运动补偿，Pixel Prediction
*PostProc
其中以VLD加速等级最高，老舊的显卡如Geforce3只支持MC加速，GeForce 8000和Radeon HD 2000都可以支援VLD。[[PowerDVD]]分别可以对H.264、VC-1、MPEG2、X264、XVID、DVIX等格式进行解压。此外DXVA還定義了一組可以讓圖形驅動實現運算加速的硬件驅動接口（Device Driver Interfaces/DDIs）。

DXVA定義了運動補償DDI，屬於[[Inverse discrete cosine transform|iDCT]]動作介面，包括[[霍夫曼编码]]，[[運動補償]]、[[alpha blending]]、inverse {{link-en|quantization|Quantization (image processing)}}、[[色彩管理|色彩空间转换]]以及幀率的變化動作等。<ref name="intro">{{cite web | url = http://msdn2.microsoft.com/en-us/library/ms799545.aspx | title = Introduction to DirectX VA | accessdate = 2007-10-24 | deadurl = yes | archiveurl = https://www.webcitation.org/678aLnI2l?url=http://msdn.microsoft.com/en-us/library/ms799545.aspx | archivedate = 2012-04-23 | df =  }}</ref><ref>{{cite web | url = http://forum.videolan.org/viewtopic.php?t=9421 | title = Microsoft DirectX Video Acceleration (DirectX VA) support | accessdate = 2007-10-24 | archive-date = 2012-04-23 | archive-url = https://www.webcitation.org/678aMSjF5?url=http://forum.videolan.org/viewtopic.php?t=9421 | dead-url = no }}</ref>其本身又有三個小細項：Deinterlacing DDI、COPP DDI以及ProcAmp DDI。<ref>{{cite web | url = http://msdn2.microsoft.com/en-us/library/ms798379.aspx | title = DirectX Video Acceleration | accessdate = 2007-10-24 | deadurl = yes | archiveurl = https://www.webcitation.org/678exRdk0?url=http://msdn.microsoft.com/en-us/library/ms798379.aspx | archivedate = 2012-04-23 | df =  }}</ref>[[deinterlace|Deinterlacing]] DDI定義了針對[[deinterlace|deinterlacing]]動作的回饋. COPP（Certified Output Protection Protocol）DDI允許管道基于[[数字版权管理]]的考虑，定義加密功能。ProcAmp DDI用於加速视频后处理，<!-- The ProcAmp driver module sits between the hardware video renderer and the display driver and provides functions for applying post-processing filters on the decompressed video.-->