MV I/O Textfile Renderer DirectShow Filter

The MontiVision I/O Textfile Renderer Filter is used to save data from a filter into a structured text file.

File:	MVIOTextfileRenderer.ax
CLSID:	CLSID_MVIOTextfileRenderer

Supported Interfaces

IMVIOTextfileRenderer

IMVFilterData

IMVAbout

MV I/O Textfile Property Page

Implements the IMVIOTextfileRenderer configuartion interface.

MontiVision I/O Text File Renderer DirectShow Filter Property Page

Create on run	The filter creates the outputfile every time the graph is started.
Create on every dataset	The filter creates a file for every dataset, received on its input pins.
Name	Path to a template file for the file name.
Folder	Output folder for the text files.
Header	Path to a template file for the file header.
Dataset	Path to a template file for a dataset.
Footer	Path to a template file for the file footer.
Edit	Start notepad with the template file.

Template files

The filter can use template files to customize the text output file. There are four templates available, one for the file name, the file header, a dataset and the file footer. All template files use the same simple syntax:

Text	Output as it is.
Variable	%Variable Name%
%	%%

Template variables

The following table shows all the available fixed variables for template files.

YEAR	4 digit year, e.g. 2003.
SHORT_YEAR	2 digit year, e.g. 03
MONTH	2 digit month, e.g. 01
MONTH_NAME	Name of the month, e.g. January.
DAY	2 digit day, e.g. 29.
DAY_NAME	Week name of the day, e.g. Monday.
WEEK	2 digit week number, e.g. 45.
HOUR	2 digit hour, e.g. 17.
MINUTE	2 digit minute, e.g. 54.
SECOND	2 digit second, e.g. 32.
DS_COUNT	Counter for the datasets since the filter graph was started.
RUN_COUNT	Counter for the run sessions of the filter graph.
FILE_COUNT	Counter for the files created by the filter.

Additionally a template can contain a variable with the name of the input pin, e.g. %Input1%. The filter substitutes the variable with the value from the input pin as a string. If the variable name is not valid the filter inserts no text for the variable.

File Name Template

The file name template describes the file name for the output data. If no file name template is selected, the filter generates no output. If a file name exists the filter overwrites the file without any prompt. You can create unique file names with the FILE_COUNT variable. If the file name template includes the FILE_COUNT variable the filter increments the counter until it finds an unused file name. If an output folder is selected, the path to the output folder is copied in front of the filename. The filter automatically adds the backslash after the folder path.

Example:

%YEAR%-%MONTH%-%DAY%-Result-%FILE_COUNT%.xml

This template would result in filenames like this: 2003-01-27-Result-1.xml

Header, Dataset, Footer Template

The other three template files describes the content of the textfile created by the filter. The header text is inserted at the beginning of the file, when opened. The footer text is written at the end of the file before the file is closed. The dataset template is used to create a text output for every dataset received on the input pins.

Example:

This example shows the template files for the filter graph showing below. It saves the two thresholds from the binary filters into an simple XML file. The binary filter uses different algorithms to calculate the threshold.

Header Template:

Footer Template:

</HEADER>

Dataset Template:

<dataset count="%DS_COUNT%" time="%HOUR%:%MINUTE%:%SECOND%">
<Value alg="Edge Pixels">%Input1%</Value>
<Value alg="Two Peaks">%Input2%</Value>
</dataset>

The example filter graph creates an output file like this: