CollectPattern

Search for a calibration pattern of the size specified in the global Pattern setting and put it into the global PatternBuffer.

If you set the (DecodeData) parameter to true, the global pattern setting will be ignored and the pattern will be inserted into the global pattern buffer with its decoded size.

In addition to putting them into the global pattern buffer, the command also returns the detected patterns in the Patterns result node. The command will also try to match all patterns detected in the left image with the patterns from the right image. If such a match is found the pattern will also be listed in the (Stereo) result node.

Note

Each pattern’s grid spacing will be stored together with the pattern point coordinates in the global pattern buffer. The grid spacing is either determined by decoding the pattern’s dot centers when specifying DecodedData as true, or by the global GridSpacing parameter.

Note

You should always clear the pattern buffer with DiscardPatterns before collecting a new pattern while tracking a non-static pattern pose.

Note

You cannot detect patterns on images where the camera’s Projector is on, unless you use the (Projector) parameter.

Requirements

  • The contrast of the pattern dots (black dots) has to be sufficient.

  • All pattern dots must be intact.

  • The angle at which the pattern is held towards the camera must not be too steep.

  • The marked corner must be intact to allow pattern orientation detection.

  • The data dots (small white dots inside the pattern dots) must be clearly visible.

  • The data data dots must be intact.

Error Symbols

  • "PatternNotFound": The calibration pattern of the defined size could not be located in both images. Make sure the pattern is clearly and completely visible in both camera images. Replace or clean the pattern if it’s damaged. (See the requirements above for more details.)

  • "PatternNotDecodable": The DecodeData parameter was specified as true but the pattern data could not be read. Ensure that the data dots are visible and not damaged in at least one of the images. Replace or clean the pattern, if the data dots are corrupted. (See the requirements above for more details.)