SLOW pattern matching in VB, FAST in VisionBuilder?????
I've built several vision aquisition and analysis apps with VB and CWIMAQ. Now, I'd like to do a pattern matching application, however, I can't seem to get the same functionality and speed with the VB component as I can using VisionBuilder! Attached is a grayscale image of a microtiterplate, and a "pattern" of a well or "hole". Using pattern matching in visionbuilder there are about 96 matches, which is perfect, dang near a match for every well. However, if I try to reverse engineer the VB "FeatureFind" example and use the attached picture and pattern, the "Correlation" takes a VERY long time (14 seconds for VB featurefind app, instant for VisionBuilder), and it doesn't even match!
Even though I can't use
visionbuilder in my final application, it works almost perfectly when I use the attached image and pattern while setting the minimum score to 50. I wish I could implement the same thing in VB, that is, if NatInst could tell me the CWIMAQ components function calls used to implement it :-0)
Any Ideas? Thanks
Attachments:
bw.tif 301 KB
test_patt.png 57 KB
I am not familiar with the VB commands you want to use since I use LabVIEW. However, I think you might be using the wrong function. It sounds like the example you tried to modify uses correlation, which is different from pattern matching. As you have seen, pattern matching is much faster and gives better results.
I would assume that the manual for CWIMAQ would give you the information you need.
Bruce
Bruce Ammons
Ammons Engineering
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Color pattern matching is very slow
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I tried this code creating one vi application.
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the color pattern matching is not as fast as 8-bit matching, but should still be fast.
For example, I am attaching a VI for color pattern matching where you load the image, create the template and search do the matching.
In my example I tried color pattern matching on color image of size 4288x2848 pixels and the matching is performed in ~140 ms (~7Hz). So, for a smaller image, I think the real-time processing is quite achievable (I consider real-time 20 Hz or more). The only problem is the template learning, which in my case takes around 10 seconds. But you should learn the template only once in the initialization stage.
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the requirement is that I have to match the columns of B in A. If there is a value with * sign, this must be present in A like 'CZ4' should exit in string A.
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, 1
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Attachments:
problem in matching while object moves far.png 515 KBHello,
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3. Before the detection fails -> rough object detection with some padded bounding rectangle (new ROI),
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You should set up the appropriate illumination first. The resolution is also important, since your object is moved back and forth (but the resolution will have a direct impact on the template learning time).
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https://decibel.ni.com/content/blogs/kl3m3n
"Kudos: Users may give one another Kudos on the forums for posts that they found particularly helpful or insightful." -
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Solved!
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you can use the VI "IMAQ Is Vision Info Present 2 VI" to reice the information:
IMAQ Is Vision Info Present 2 VI - NI Vision 2011 for LabVIEW Help - National Instruments
http://zone.ni.com/reference/en-XX/help/370281P-01/imaqvision/imaq_is_vision_info_present_2/
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Attachments:
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I have an regex i.e. Pattern.compile("([0-9])D([0-9])'?(?:([0-9]+)\")?([NSEW])").{code}
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I missed the '+' in my original regex Pattern.compile("([0-9]+)D([0-9]+)'?(?:([0-9]+)\")?([NSEW])"){code}.
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<State name="NORTH CAROLINA">
<City name="Asheville AP" Lat="35D26'N" Lon="82D32'W"/>
<City name="Charlotte AP" Lat="35D13'N" Lon="80D56'W"/>
<City name="Durham" Lat="35D52'N" Lon="78D47'W"/>
<City name="Elizabeth City AP" Lat="36D16'N" Lon="76D11'W"/>
<City name="Fayetteville, Pope AFB" Lat="35D10'N" Lon="79D01'W"/>
<City name="Goldsboro,Seymour-Johnson" Lat="35D20'N" Lon="77D58'W"/>
<City name="Greensboro AP (S)" Lat="36D05'N" Lon="79D57'W"/>
<City name="Greenville" Lat="35D37'N" Lon="77D25'W"/>
<City name="Henderson" Lat="36D22'N" Lon="78D25'W"/>
<City name="Hickory" Lat="35D45'N" Lon="81D23'W"/>
<City name="Jacksonville" Lat="34D50'N" Lon="77D37'W"/>
<City name="Lumberton" Lat="34D37'N" Lon="79D04'W"/>
<City name="New Bern AP" Lat="35D05'N" Lon="77D03'W"/>
<City name="Raleigh/Durham AP (S)" Lat="35D52'N" Lon="78D47'W"/>
<City name="Rocky Mount" Lat="35D58'N" Lon="77D48'W"/>
<City name="Wilmington AP" Lat="34D16'N" Lon="77D55'W"/>
<City name="Winston-Salem AP" Lat="36D08'N" Lon="80D13'W"/>
</State>
public final class GeoLine {
/* Enum for the possible directions of longitude and latitude*/
public enum Direction {
N, S, E, W;
public boolean isLongitude() {
return (this == E || this == W);
public boolean isLatitude() {
return (this == N || this == S);
public Direction getCanonicalDirection() {
if (this == S) {
return Direction.N;
} else if (this == W) {
return Direction.E;
} else {
return this;
private final int degree;
private final int minute;
private final int second;
private final Direction dir;
/* Recognizes longitude and latitude values that has degrees, minutes and seconds i.e. "45D15'34"N
* or "45D1534"N. The single-quotes for the minutes is optional. And, for the moment we do not support seconds
* validation although ilog library returns the longitude/latitude with second when NEs and Sub-networks are
* dragged and dropped on the map.*/
private static final Pattern PATTERN = Pattern.compile("([0-9]+)D([0-9]+)'?(?:([0-9]+)\")?([NSEW])");
public GeoLine(int degree, int minute, Direction dir) {
this(degree, minute, 0, dir);
public GeoLine(int degree, int minute, int second, Direction dir) {
Log.logInfo(getClass().getSimpleName(), "PAU degree: " + degree + " minute: " + minute + " second: " + second + " direction: " + dir);
verifyLongitudeLatitude(degree, dir);
verifyMinute(degree, minute, dir);
this.degree = degree;
this.minute = minute;
this.second = second;
if (this.degree == 0 && this.minute == 0 && this.second == 0) {
this.dir = dir.getCanonicalDirection();
} else {
this.dir = dir;
public Direction getDirection() {
return dir;
public int getMinute() {
return minute;
public int getDegree() {
return degree;
public int getSecond() {
return second;
public static GeoLine parseLine(String location) {
* Matcher class will throw java.lang.NullPointerException if a null location
* is passed, null location validation is not needed.
Matcher m = PATTERN.matcher(location);
if(m.matches()) {
int deg;
int min;
int second;
Direction direction;
deg = Integer.parseInt(m.group(1));
min = Integer.parseInt(m.group(2));
if (m.group(3) == null) {
second = 0;
} else {
second = Integer.parseInt(m.group(3));
direction = Direction.valueOf(m.group(4));
return new GeoLine(deg, min, second, direction);
} else {
throw new IllegalArgumentException("Invalid location value. Expected format XXDXX'XX\"[NSEW] " + location);
private void verifyMinute(int deg, int min, Direction direction) {
/* This validation is to make sure that minute does not exceed 0 if maximum value for latitude == 90
* or longitude == 180 is specified */
int maxDeg = direction.isLatitude() ? 90 : 180;
if(min < 0 || min > 59) {
throw new NumberFormatException("Minutes is out of range. Value should be less than 60: " + min);
if (deg == maxDeg && min > 0) {
throw new NumberFormatException("Degree value " + deg + "D" + direction + " cannot have minute exceeding 0: " + min);
private void verifyLongitudeLatitude(int valDeg, Direction valDir) {
int max = valDir.isLatitude() ? 90 : 180;
if(valDeg < 0 || valDeg > max) {
throw new NumberFormatException("Degree " + valDeg + valDir + " is invalid");
public final boolean isLongitude() {
return dir.isLongitude();
public final boolean isLatitude() {
return dir.isLatitude();
@Override
public final String toString(){
if(minute < 10){
return degree + "D0" + minute + dir;
} else {
return degree + "D" + minute + dir;
@Override
public boolean equals(Object obj) {
if (obj instanceof GeoLine) {
GeoLine other = (GeoLine) obj;
return (this.degree == other.degree && this.minute == other.minute && this.second == other.second && this.dir == other.dir);
return false;
@Override
public int hashCode() {
int result = 17;
result = result * 37 + degree;
result = result * 37 + minute;
result = result * 37 + second;
result = result * 37 + dir.hashCode();
return result;
}Thank you again. -
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Target : REHL
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