How to disable or enable Logitech Video Effects for individual programs

Purpose

There are rare cases where the Logitech Video Effects component interferes with the correct functioning of a program. In most cases this is limited to software using webcam devices although other programs have also been affected in the past.

Prerequisities

This article contains information about changing advanced settings of your Windows system. Good knowledge of the system is required before doing any of the steps in this article. If you do not feel comfortable with any of the steps mentioned please do not follow the instructions as improper usage of the tools described could negatively affect your system, in particular the correct functioning of the Logitech QuickCam software package.

Background

The Logitech Video Effects filter loads a dynamic library into all applications in order to allow any application accessing the webcam to take advantage of the Logitech Video Effects controlled through the QuickCam software.

There are several ways to control the loading of the Logitech Video Effects library into applications. On the one hand there are three blacklists that can be used in cases where LVPrcInj.dll or LVPrcInj01.dll produce unexpected behavior or crashes with certain applications. On the other hand there is a whitelist that can force the library to be loaded into certain processes.

QuickCam versions up until 11.80 load the Logitech Video Effects library into all applications by default unless that application is blacklisted.

Later versions of QuickCam (i.e. versions higher than 11.80) have a different behavior: They only load the Logitech Video Effects library into pre-selected and tested programs that are part of the whitelist.

All these lists can be edited with the Logitech UMVPLReg utility which is introduced in the following section.

Blacklisting applications

There are different criteria based on which a process can be excluded from the Logitech Video Effects library:

• Process name. Processes can be blacklisted by process name, e.g. MyApp.exe.
• Loaded modules. If a process is using a certain DLL, the Logitech Video Effects filter will be disabled for that process. For example, all processes using MyLib.dll can be excluded from the Logitech Video Effects filter if MyLib.dll is known to be incompatible with the latter.
  
• Manufacturer name. Processes whose executables carry the name of a given manufacturer in their file properties are excluded from the Logitech Video Effects filter.

Whitelisting applications

Similar to the process name blacklist the whitelist can contain an unlimited number of process names. If a process is on the whitelist the Logitech Video Effects library is loaded into it.

Blacklist vs. whitelist

Note that the blacklist and whitelist mechanism are exclusive, i.e. either the blacklists are active or the whitelist is. QuickCam applications up until 11.80 only respect the blacklists while QuickCam applications 11.90 and higher only respect the whitelist.

The UMVPLReg tool

When you start the UMVPLReg tool you will be presented with the following window:

There are two areas in the window. The left one shows the different blacklists and the whitelist while the right one allows selecting currently running process names, manually entering process and library names, and entering manufacturer strings.

Exclude a given process from the Logitech Video Effects filter (QuickCam 11.80 and earlier only)

1. Determine the name of the process for which the Logitech Video Effects filter causes problems.
2. Launch the UMVPLReg.exe. A window similar to the screenshot above will show up.
   
3. On the left side you can select among four different lists. Choose Unwanted Processes from the drop-down menu.
4. If the process you want to exclude is currently running you can select it from the Process List on the right side. If the process is not currently running enter its name in the Other field. In both cases click the corresponding arrow button to add the process to the list of unwanted processes.
5. Click OK to apply the changes and exit the tool or Apply to apply the changes without exiting UMVPLReg.
6. Restart the computer for the changes to take effect.
   

Exclude processes that load certain modules from the Logitech Video Effects filter (QuickCam 11.80 and earlier only)

1. Determine the name of the module (i.e. DLL) that causes problems when it is loaded into the same process as the Logitech Video Effects library.
2. Launch the UMVPLReg.exe. A window similar to the screenshot above will show up.
   
3. On the left side you can select among four different lists. Choose Unwanted Modules from the drop-down menu.
4. Enter the module name in the Other field and click the arrow button next to it.
5. Click OK to apply the changes and exit the tool or Apply to apply the changes without exiting UMVPLReg.
6. Restart the computer for the changes to take effect.

Exclude processes of certain manufacturers from the Logitech Video Effects filter (QuickCam 11.80 and earlier only)

1. Determine the name of the manufacturer whose applications have problems with the Logitech Video Effects library. You can use one of the following methods to retrieve this name. Note that the list entries are case-insensitive and subject to substring matching (i.e. blacklisting "My Company" also blacklists executables from "My Company Inc." and "The My Company Webcam Group").
   
• In Explorer open the File Properties dialog of the executable in question. The manufacturer can be seen in the Version tab under the Company item.
• Open the executable in question with a resource editor such as the one integrated in Visual Studio. The manufacturer can be seen in the CompanyName property of the version information resource.
2. Launch the UMVPLReg.exe. A window similar to the screenshot above will show up.
   
3. On the left side you can select among four different lists. Choose Unwanted Manufacturers from the drop-down menu.
4. Enter the manufacturer name in the Other field and click the arrow button next to it.
5. Click OK to apply the changes and exit the tool or Apply to apply the changes without exiting UMVPLReg.
6. Restart the computer for the changes to take effect.

Enable the Logitech Video Effects filter for a given process (QuickCam 11.90 and later only)

1. Determine the name of the process for which you want to enable the Logitech Video Effects filter.
2. Launch the UMVPLReg.exe. A window similar to the screenshot above will show up.
   
3. On the left side you can select among four different lists. Choose Wanted Processes from the drop-down menu.
4. If the process you want to include is currently running you can select it from the Process List on the right side. If the process is not currently running enter its name in the Other field. In both cases click the corresponding arrow button to add the process to the list of whitelisted processes.
5. Click OK to apply the changes and exit the tool or Apply to apply the changes without exiting UMVPLReg.
6. Restart the computer for the changes to take effect.

Links

• Logitech Support FAQ: The QuickCam LVPRCINJ.DLL file causes applications to crash