Integrating Intel^® EMGD DirectX DirectShow Codecs

Intel^® EMGD DirectShow Codecs Overview

Microsoft's DirectX DirectShow infrastructure provides a standardized interface for middleware audio-video codec software libraries to expose features for accelerating video and audio processing. This infrastructure does not differentiate between hardware and software acceleration but the middleware codec libraries have the choice of employing either method. For the purpose of enabling hardware accelerated video decode on Windows Embedded Compact 7, the Intel^® EMGD Windows Embedded Compact 7 DirectShow filters are provided in the form of middleware codec libraries (DLLs) that will interface with the Intel^® EMGD Windows Embedded Compact 7 driver to operate.

The Intel^® EMGD DirectShow package includes the following Windows Embedded Compact 7 codecs that are DirectShow transform filters in .dll binary form:

• mpeg2_dec_filter.dll

• mpeg2_spl_filter.dll

• mpeg4_dec_filter.dll

• mp3_dec_filter.dll

• mpeg4_spl_filter.dll

• h264_dec_filter.dll

• aac_dec_filter.dll

• ac3_dec_filter.dll

The codecs with “spl” are splitter codecs.

Notes: Intel^® EMGD DirectShow codecs are supported only on the Windows Embedded Compact 7 operating system.

Intel^® EMGD splitter filters can connect with most source filters but have been verified to connect only with Intel^® EMGD transform filters on its downstream pins. The same case is true with respect to Intel^® EMGD transform filter connection with upstream splitter filters.

Important: Intel^® EMGD audio and video codec filters work only with Intel^® EMGD splitter filters. If these codecs are installed properly into the Windows Embedded Compact 7 OS image (via registry changes), the vplayer.exe is able to load and use Intel^® EMGD codecs without any help.

Installing Intel^® EMGD DirectShow Codecs

Prerequisites:

• At least 512 MB RAM for the target system. The hardware video decode performance depends on what other processes are being run on the system.

• The target system must contain the chipset or processor that supports the video engine.

• Include Intel^® EMGD Graphics Driver in the Windows Embedded Compact 7 OS image per the appropriate installation instructions in Installation and Setup.

For the latest EVALUATION ONLY versions of the Intel^® EMGD DirectShow codecs, contact your Intel FAE or open a QuAD case and request the codecs.

After you have the codec package, follow these steps to set up the Intel^® EMGD DirectShow codecs:

1. Ensure that the Intel^® EMGD DirectShow codecs are included in the Windows Embedded Compact 7 OS image. You do this by including it into either the platform.bib or project.bib file. See Installation and Setup, step 13. for an example.

2. Ensure that the emgd_filters.reg file is included into the image registry. You do this by including it into either the platform.reg or project.reg file. See Installation and Setup, end of step 12. for an example.

3. Set the backbuffers required for Intel^® EMGD Codecs on the Microsoft video renderer filter for smoother performance by changing the following registry key:

[HKEY_LOCAL_MACHINE\Software\Microsoft\DirectX\DirectShow\Video Renderer]

“MaxBackBuffers”=dword:X

where X is the current value that you need to change to equal to or greater than 5.

4. For smoother playback and lower CPU utilization, ensure you use interrupts with Intel^® EMGD if available. See Installation and Setup for details.