LEAD Screen Capture Filter (2.0)

The Screen Capture Filter is a DirectShow source filter that delivers a video stream The portion of the file holding the video data. The video data might be compressed to save disk space. The data has to be decompressed using a video decompressor Also known as a decoder, this is a module or algorithm to decompress data. before you can play (see) it. captured from the screen. This filter can capture from the full screen, a window, or a region. Many options are provided for flexibility and convenience. These are summarized as follows:

Capturing source:

The following options are available for the capturing source:

Option

Description

CAPTURE_FULLSCREEN

The capturing source is the full screen. This can be the whole screen or just some region defined by screen coordinates.

CAPTURE_ACTIVEWINDOW

The capturing source is the active window. This can be the whole active window or just some region defined by window coordinates.

CAPTURE_ACTIVECLIENT

The capturing source is the client area of the active window. This can be the whole client window or just some region defined by window coordinates.

CAPTURE_SELECTEDWINDOW

The capturing source is some chosen window, not necessarily the active window. This can be the whole window area, client and non-client or just some region defined by window coordinates.

 

In case the capturing source is not CAPTURE_FULLSCREEN (neither the whole screen nor a region), the filter provides an option to track the capturing source so that no matter where the source is moved, the captured contents are the same. For more information, refer to the TrackWindow property of the ILMScrCap Interface. When the capture source goes off screen or gets covered partially by another window, the filter can fill the hidden area with some color or just capture whatever contents are in the capture area.

Notification:

The filter provides notification of many events to enable the user to have control over the capturing process and make the right decision. In addition, the filter provides informational notifications. The notification is provided through a callback mechanism where the user should have an object that implements the ILMScrCapUserCallback and ILMScrCapUserEventsCallback Interfaces. For more information, refer to ILMScrCapUserCallback Interface, ILMScrCapUserEventsCallback.

On event action:

The filter can be configured to take specific actions on specific events. For more information, refer to the OnSourceMinimize, OnSourceClose, and OnSourceAreaChange properties of the ILMScrCap Interface.

Tools:

The filter provides tools for region selection and window selection. The user can use these tools programmatically, integrating them with a custom user interface. Many options are provided with these tools for convenience. For more information, refer to SelectRegionTool and SelectWindowTool methods, and the ShowXXXX properties of the ILMScrCap Interface.

Other:

Other options and helper properties are provided for flexibility and convenience. For more information, refer to the properties and methods of the ILMScrCap Interface, the ILMScrCapUserCallback Interface, and the ILMMCommon Interface. All the mentioned functionalities are exposed through both user and programming interfaces.

 

Filter Interface(s)

ILMScrCap, ILMScrCapUserCallbackILMScrCapUserEventsCallback, ILMMCommon

Interface ID

IID_ILMScrCap, IID_ILMScrCapUserCallback, IID_ILMMCommon

Output Media Types

MEDIATYPE_Video
The offered subtype depends on the current screen settings. It should be one of the following:
MEDIASUBTYPE_RGB32,
MEDIASUBTYPE_RGB24,
MEDIASUBTYPE_RGB555,
MEDIASUBTYPE_RGB8,
MEDIASUBTYPE_RGB4, and
MEDIASUBTYPE_RGB1.

Filter CLSID

CLSID_LMScrCap

Property Page(s) CLSID

CLSID_LMScrCapPropertyPage

Filter category

CLSID_VideoInputDeviceCategory

Executable

LMScrCap2.dll, DSKernel2.dll

Header

ILMScrCap2.h

 

LEAD Screen Capture Filter User Interface

You need to unlock the LEAD Screen Capture Filter (2.0) to use the filter in RELEASE mode.

For more information, refer to:

 LEAD DirectShow Modules Evaluation Mechanism.