Image Acquisitionand Proces

Recommendations

Info

Image Analysis 171 7.1.3 A PRACTICAL EXAMPLE The example in Figure 7.7 uses Interactive Pattern Matching Example.vi (which is on the accompanying CD-ROM) to: • Prompt the user to load an image to be searched. • Interactively deÞne a rectangular ROI (the search template). • Set search parameters. • Perform a pattern matching. Once the source image has been loaded, the user deÞnes a ROI, and then presses the Learn Template button, which calls the code shown in Figure 7.8. As you can see, the ROI’s global rectangle is returned, and its corresponding underlying portion is extracted from the source image — this forms the search template. The next step is to train the system to recognize it, which is achieved by Þrst deÞning the learn pattern parameters using IMAQ Setup Learn Pattern. This VI simply creates a learn pattern parameter string based on one input: learn mode. Learn mode speciÞes the invariance mode to use when learning the pattern. You can choose from values shown in Table 7.2. Once the template is learned, the next step is to search for it. First, deÞne searching criteria with IMAQ Setup Match Pattern. Like IMAQ Setup Learn Pattern, this VI simply constructs a match pattern parameter string based on its inputs (Table 7.3). The actual searching process is executed in IMAQ Match Pattern. Feed the source image, template and match pattern parameters (from IMAQ Setup Match Pattern) into this VI, and it will search the source for the template. Two further methods of increasing the speed of the search include deÞning a rectangle within the source image to be searched (if you know that the object is going to be in a particular area of the source image, then there is no sense in searching the whole image), and deÞning the number of matches requested. If you are sure that the image will only have a maximum number of instances of the search object, once they are found it wastes time looking for further instances (Figure 7.9). The same pattern match could be even faster. Simply rotate the source image and template 180∞ before performing the search, which causes even less of the source
172 Image Acquisition Processing with LabVIEW FIGURE 7.7 Interactive pattern matching example. FIGURE 7.8 Learn template — wiring diagram. image to be searched (the searching routine works from left to right, and then from top to bottom), and the last of the three objects will be closer to the top of the image. Simple pattern matching is achieved using the code shown in Figure 7.10.
Page 3:
IMAGE PROCESSING SERIES Series Edit
Page 6:
Foreword The introduction of LabVIE
Page 9 and 10:
FIGURE 1 Vision 6.1 FIGURE 2 Compan
Page 12 and 13:
Acknowledgments My gratitude goes o
Page 14:
Dedication To Don “old fella” P
Page 18 and 19:
Contents Chapter 1 Image Types and
Page 20 and 21:
Chapter 4 Displaying Images........
Page 22 and 23:
Chapter 7 Image Analysis...........
Page 24 and 25:
1 Image Types and File Management F
Page 26 and 27:
Image Types and File Management 3 F
Page 28 and 29:
Image Types and File Management 5 A
Page 30 and 31:
Image Types and File Management 7 C
Page 32 and 33:
Image Types and File Management 9 p
Page 34 and 35:
Image Types and File Management 11
Page 36 and 37:
Image Types and File Management 13
Page 38 and 39:
2 Setting Up You should never under
Page 40 and 41:
Setting Up 17 FIGURE 2.3 (a) Interl
Page 42 and 43:
Setting Up 19 Linear Aray Light Sou
Page 44 and 45:
Setting Up 21 FIGURE 2.7 National I
Page 46 and 47:
Setting Up 23 2.1.3.2 Control and I
Page 48 and 49:
Setting Up 25 FIGURE 2.11 X-Ray ima
Page 50 and 51:
Setting Up 27 Apple Computer techno
Page 52 and 53:
Setting Up 29 FIGURE 2.17 An inexpe
Page 54 and 55:
Setting Up 31 Although this would b
Page 56 and 57:
Setting Up 33 134 -115 \ Contrast =
Page 58 and 59:
Setting Up 35 resolution printer wi
Page 60 and 61:
Setting Up 37 C A B C Traditional T
Page 62 and 63:
Setting Up 39 Camera Light Source O
Page 64 and 65:
Setting Up 41 Camera Light Source (
Page 66 and 67:
Setting Up 43 FIGURE 2.37 (a) An ob
Page 68:
Setting Up 45 FIGURE 2.41 (a) PCB p
Page 71 and 72:
48 Image Acquisition Processing wit
Page 73 and 74:
Page 75 and 76:
Page 77 and 78:
Page 79 and 80:
Page 81 and 82:
Page 83 and 84:
Page 85 and 86:
Page 87 and 88:
Page 89 and 90:
Page 91 and 92:
Page 93 and 94:
Page 95 and 96:
Page 97 and 98:
Page 99 and 100:
Page 101 and 102:
Page 103 and 104:
Page 105 and 106:
Page 107 and 108:
Page 109 and 110:
Page 111 and 112:
Page 113 and 114:
Page 115 and 116:
Page 117 and 118:
Page 119 and 120:
Page 121 and 122:
Page 123 and 124:
100 Image Acquisition Processing wi
Page 125 and 126:
Page 127 and 128:
Page 129 and 130:
Page 131 and 132:
Page 133 and 134:
Page 135 and 136:
Page 137 and 138:
Page 139 and 140:
Page 141 and 142:
Page 143 and 144: 120 Image Acquisition Processing wi
Page 164 and 165: 6 Morphology When applied to vision
Page 166 and 167: Morphology 143 I Closed { } = Erode
Page 168 and 169: Morphology 145 FIGURE 6.3 Simple mo
Page 170 and 171: Morphology 147 FIGURE 6.5 Custom st
Page 172 and 173: Morphology 149 FIGURE 6.8 Particle
Page 174 and 175: Morphology 151 FIGURE 6.12 Fill hol
Page 176 and 177: Morphology 153 FIGURE 6.17 Danielss
Page 178 and 179: Morphology 155 Detected circles wit
Page 180 and 181: Morphology 157 6.5 CASE STUDY: FIND
Page 182 and 183: Morphology 159 6.6 USER SOLUTION: D
Page 184 and 185: Morphology 161 ULTRASOUND MACHINE (
Page 186: Morphology 163 FIGURE 6.31 The Edit
Page 193: 170 Image Acquisition Processing wi
Page 240 and 241: 8 Machine Vision A generally accept
Page 242 and 243: Machine Vision 219 TABLE 8.1 “IMA
Page 244 and 245:
Machine Vision 221 TABLE 8.3 Input
Page 246 and 247:
Machine Vision 223 packages, includ
Page 248 and 249:
Machine Vision 225 good sense to ad
Page 250 and 251:
Machine Vision 227 TABLE 8.4 “IMA
Page 252 and 253:
Glossary 1-Bit Image An image compr
Page 254 and 255:
Glossary 231 binary display device
Page 256 and 257:
Glossary 233 spatial Þlters, each
Page 258:
Glossary 235 Resolution There are t
Page 261 and 262:
Page 263 and 264:
Page 265 and 266:
Page 267:
show all

Image Acquisitionand Proces

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?