Common DirectShow Filter Functionalities
The following interfaces are commonly used
by all MontiVision DirectShow Filters, even if some filters do not
support all of them.
IMVHistogram
IMVHistogram2
IMVHistogram3
IMVRegionOfInterest (See
ROI Concept)
IMVFilterData
IMVAbout
IMVFilterInfo
Property Pages
MontiVision DirectShow Filters using
the IMVHistogram,
IMVRegionOfInterest, IMVFilterData or IMVAbout interfaces, include a property
page to configure those filters. The following section describes
how to use the MontiVision standard property pages.
Histogram Property
Page
Region Of Interest Property
Page (See ROI Concept)
Filter Data Property
Page
About Property
Page
Histogram Property
Page
The histogram property page uses the
IMVHistogram interface to display
the histogram of the processed image.

Histogram property page
| Update |
Updates the histogram. The update is done
automatically if the pin direction, pin number or colour
channel is changed. |
| Direction |
If input is selected, the histogram of the
image is taken before the image is processed by the image
processing algorithm. Otherwise the histogram is taken after the
image is processed. |
| Pin |
If the filter supports multiple input or
output pins, the desired pin can be selected. |
| Channel |
If RGB images are being processed,
the channel of interest can be chosen. If "All" is chosen, all
channels are added up and displayed in one histogram. |
| Clipping |
Clipping is useful when the processed
image is over or underexposed. If (for example) the image is
overexposed, the histogram value for white pixels (value
255) will be very high. Clipping the white value will result in a
better view of the histogram. |
| Histogram values |
The mouse is used to get the histogram
values. If the mouse is positioned somewhere inside the histogram
window, the value of the histogram index at that position is
displayed. |
Region Of InterestProperty
Page
The ROI property page uses the
IMVRegionOfInterest interface to display and modify the ROIs and
COIs of the processed image. Some MontiVision image processing
filters support different ROIs for the input and the output image.
That can be used to show results of the processed input ROI at
another position in the output image. In the example below, the
input ROI is different from the output ROI and the result of
the process is displayed in the lower left corner of the output
image. NB: If the result has to be shown at its original position,
both ROIs have to be equal. For additional information
please take a look at the ROI concept.

Region Of Interest property page
| Direction |
If input is selected, the ROI of the input
image is modified. Otherwise the ROI of the output image is
modified. |
| Pin |
If the filter supports multiple input or
output pins, the desired pin can be selected. |
| COI |
If RGB images are processed and
channel of interest operations are supported, the channel of
interest can be chosen. If "All" is chosen, all channels are
modified. If a single channel is chosen, the output COI has to be a
single channel too. If for example the input COI is set to "G"
(green) and the output COI is set to "R" (red), the green
colour channel of the input is processed and copied to the red
colour channel of the output image. |
| Origin |
Used to adjust the position of the
lower left corner of the ROI. |
| Dimension |
Used to adjust the dimension of the
ROI. |
| Link ROI's |
Used to adjust input and output
ROI together, useful if the ROIs are set to the same
region. |
| Copy image |
If the control is checked, the original
image is copied from the input to the output. That is useful, if
you process an ROI and want to keep the background of the original
image. The example below shows a ROI processed image with
background image enabled. |
ROI Example (Different
input and output ROIs):

ROI output image
Filter Data
Property Page
The filter data property page uses the
IMVFilterData interface to load and save filter configurations to
the registry. Therefore it uses the filter's standard registry
key.

Load/Save property page
About Property
Page
The about property page uses the IMVAbout
interface to display information about the filter and its
registration. .

About dialog property page
|