MV Buffer Access DirectShow Filter
The MontiVision Buffer Access filter
provides direct access to the frame buffer of a RGB video
stream through use of a callback interface. Applications
implement the interface and deliver an interface pointer to the MV
Buffer Access filter. The ProcessBuffer(...) method of the
callback interface is called by the filter for every processed
video frame. This filter is the optimal solution when you are
planning to integrate hardware independent video
processing functionality into an existing application that
needs to access the image data. There are two different callback
interfaces available, IMVBufferAccessCallbackVB is
designed for Visual Basic applications and IMVBufferAccessCallbackC for
C/C++ applications. The IMVBufferAccessCallbackC interface provides
greater performance, simply because the image buffer is accessed
using pointers, whereas the Visual Basic style interface utilizes
the SafeArray type.
This MontiVision DirectShow Filter is used in combination with
the MontiVision
Smart Control in the BufferAccess
Sample Application.
| File: |
BufferAccess.ax |
| CLSID: |
CLSID_MVBufferAccess |
Supported Interfaces
IMVBufferAccess
IMVBufferAccess2
IMVHistogram
IMVHistogram2
IMVHistogram3
IMVAbout
IMVFilterInfo
Supported COM Events
The filter supports following events through the IMVFilterEvents interface.
Look at the filter events page
for more information.
| Event
|
Value
|
Description
|
| MV_ALGORITHM_START_EVENT |
0
|
A filter starts processing a video frame or sample. |
| MV_ALGORITHM_END_EVENT |
1
|
A filter finishes processing a video frame or sample. |
Callback Interfaces Used
IMVBufferAccessCallbackVB
IMVBufferAccessCallbackVBDirect
IMVBufferAccessCallbackC
|