Change the default Video Decoder for wmp12 in Windows 7

Recently, some foreign users reported that there were many problems when using Windows 7 RC Windows Media Player (wmp12) to play HD videos in the MKV format. The playback was not smooth and subtitles could not be loaded, cannot be regressed. So the user gave feedback to the Windows 7 Development Team, and soon he got a reply: Microsoft said this problem may be caused by poor compatibility between the decoder and Windows 7, we recommend that you change the decoder and try again.

This user used graphedit to check and found that the decoder used was Microsoft DTV/DVD decoder that came with Windows 7. According to the reply provided by Microsoft, the problem should be the decoder that comes with Windows 7 RC.

The problem is found, and the solution is simply to replace the built-in decoder with other decoder. However, it is easy to say that the actual operation still takes some effort. According to the solution provided by a foreign website named hacking Windows 7 media center, this operation can be implemented only by modifying the registry.

Follow these steps: (we recommend that you back up the Registry first, just in case)

1. Start the Registry Editor and Navigate to HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ DirectShow \ preferred.

2. Right-click "preferred" and select "Permissions )"

3. click "advanced" in the lower-right corner of the window, go to the "owner" tab, and select "Administrators" in the "change owner" box ", check "replace owner on subcontainers and objects" at the bottom and click "OK" to make the operation take effect.

4. Return to the "Permissions" window, select "Administrators" in the "Security" box above, and select "allow" with full control in "permissions of Administrators" below ". In this way, you can modify the Registry's preferred item.

5. Find the two items in the content box on the right:

{E06d8026-db46-11cf-b4d1-00805f6cbbea}

{31435641-0000-0010-8000-00aa00389b71}

Double-click them, and the "Edit string" dialog box is displayed. Fill in the data value with the decoder CLSID (Class Identifier) You want to use ).

The clsid of some common decoder is as follows:
Ffdshow-{04fe9017-f873-450e-871e-ab91661a4ef7}
Mpcvideodecoder-{008bac12-fbaf-497b-9670-bc6f6fbae2c4}
Coreavc-{09571a4b-f1fe-4c60-9760-de6d310c7c31}

After that, restart the computer.

The preceding operations only use a third-party decoder for wmp12 to play a local video file.