MV Recording DirectShow Filter
The MontiVision Recording filter is used to record video.
It can record time lapses and take snapshots. It provides two
outputs, one preview output pin and one recording pin. Therefore
you are able to start and stop the video recording without
rebuilding the filter configuration. It also provides a time
lapse functionality. If the time lapse is activated, a video frame
is sent to the recording output pin periodically, according to
the specified time lapse interval. The third mode (snapshots) uses
a trigger and sends a frame to the recording output for each
trigger event. The snapshot mode can be controlled using either the
IMVRecording or the IMVTrigger interface. The time stamps for the
recording output are set by the recording filter. Therefore
you are able to create video streams from snapshots or time lapse
frames (see the example at the bottom of the page).
This MontiVision DirectShow Filter is used in combination with
the MontiVision
Smart Control in the MotionDetection
Sample Application.
| File: |
MVRecording.ax |
| CLSID: |
CLSID_MVRecording |
Supported Interfaces
IMVRecording
IMVTrigger
IMVFilterData
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. |
| MV_RECORD_START_EVENT |
19
|
The filter started to record video. |
| MV_RECORD_END_EVENT |
20
|
The filter stopped video recording. |
Supported I/O Pins
| I/O Pin
|
Corresponding method
|
Discription
|
Control
[Boolean] |
IMVRecording::StartRecording
IMVRecording::StopRecording
|
Recording mode:
Starts and stops the video recording.
|
|
|
IMVRecording::StartTimeLapse
IMVRecording::StopTimeLapse |
Time lapse mode:
Starts and stops the time lapse. |
|
|
IMVTrigger::Trigger |
Snapshot mode: Starts the capture of a
snapshot, depending on the trigger mode.
Example: If the trigger mode is
MV_TRIGGER_RISING_EDGE, a snapshot is taken after the the Control
I/O pin changes its state from FALSE to TRUE. |
Attention:
I/O Pins are dominat, what means that they have a higher
priority than the corresponding method of the filters
interface!
MV Recording Property Page
Implements the IMVRecording configuration
interface.
| Recording
mode |
Used to select the desired video recording mode. |
| Control |
Used to start and stop the video recording or the time lapse
functionality. If snapshot mode is selected, the start button is
used to take a snapshot. |
| Output video
frame rate |
- Don't modify frame rate
The timing of the
recorded video is not modified. If for example time lapse recording
is activated and the interval is set to 1 second, the resulting
output video frame rate would be 1 frame per second.
- Create video with 25 frames/s
The resulting
video stream on the recording output pin will have a frame
rate of 25 frames per second.
- Custom
Specify a different frame rate for the
recorded output video stream, for example 30 frames per
second.
|
| Set time lapse
interval |
Used to specify the desired time lapse interval. |
Example:
The time lapse mode is activated, the interval is set to 1
second and the recording output is connected to a file writer
filter. The output video stream frame rate is set to 25 frames per
second. After the graph is started a video frame is send to the
recording output every second, but the file created by the
file writer filter will be an AVI file with a frame rate of 25
frames per second. In the example shown below the time lapse
recording is aditionally compressed using a MJPEG codec.
|