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Halcon

HALCON 9.0 Image Acquisition Interface for Crevis USB 2.0 Cameras

This page provides the documentation of the HALCON Crevis image acquisition interface for accessing the USB 2.0 cameras from Crevis corporation. Registered customers can download the latest revision of this interface from the MVTec WWW server.

Revision: 4.0

System Requirements

  • Intel compatible PC with Windows 2000/XP/Vista and USB 2.0 interface.
  • Installed MCamU_Basic SDK and driver (version 1.0.0.9 or higher) from Crevis. Typically, these files reside in the directory %CREVIS_CAM_ROOT%.
  • HALCON image acquisition interface hAcqCrevis.dll or hAcqCrevisxl.dll, respectively.
    If you have properly installed the interface, both DLLs should reside in bin\%HALCONARCH% within the HALCON base directory %HALCONROOT% you have chosen during the installation of HALCON.

Features

  • Multiple cameras.
  • Synchronous and asynchronous grabbing.
  • HRS and binning mode.
  • External trigger with adjustable trigger delay.
  • Software control of exposure and gain.
  • Software control of the strobe parameters.

Limitations

  • grab_data and grab_data_async are not supported.
  • No LUTs.

Using Multiple Cameras

When using multiple Crevis cameras, please make sure that each cameras has an unique Device ID. You can manually set these Device IDs using the auxiliary program AdjCam.exe which is part of the Crevis installation S/W.

Description

Parameters for open_framegrabber():

Name 'Crevis' The name of the HALCON image acquisition interface.
HorizontalResolution 1 The desired horizontal image resolution. Use only 1 for full resolution. Default: 1.
VerticalResolution 1, 2, 3, 4, 17, 18, 19, 20 The desired vertical image resolution. Use 1 for full resolution, or 2~4 for HRS, 17 for binning, and 18~20 for binning with HRS. Default: 1.
ImageWidth --- Ignored.
ImageHeight --- Ignored.
StartRow --- Ignored.
StartColumn --- Ignored.
Field --- Ignored.
BitsPerChannel 8, 10 Number of bits per image channel. Please note that this parameter must correspond to the PixelFormat setting in the camera, e.g., use 8 in case of PixelFormat=Mono8 and 10 for PixelFormat=Mono16. To change the value in the camera, specify PixelFormat to Mono8 or Mono16 by using AdjCam.exe and re-start the camera. Default: 8.
ColorSpace 'gray', 'rgb', 'bayer' Specifies the desired color space and thus the number of image channels of the resulting HALCON image. Default: 'gray'.
Generic --- Ignored.
ExternalTrigger 'true', 'false' Activate/deactivate external triggering. Default: 'false'.
CameraType 'default',
'MV-BS20U',
'MV-BX30U',
'MV-BV20U',
'MV-BV30U'
The camera type will be detected automatically ('default'). Default: 'default'.
Device '-1', DeviceId (string) The ID of the desired camera, see also 'Using Multiple Cameras' above. Default: '-1' (searches for the first unused camera).
Port --- Ignored.
LineIn --- Ignored.

Parameters for set_framegrabber_param():

'acquisition_invalid_time' min ... max (long) Used to check the validity of grabbed image. If the time difference between the grabbed image and "grab command" is less than this time, it means that the grabbed image is not newer than the old image before calling "grab command". Default: One frame time (milliseconds).
'black_level' 0 ... 255 (long) Controls the analog black level as a raw integer value. This represents a DC offset applied to the video signal.
'continuous_grabbing' 'disable', 'enable' Used for special acquisition mode of real-time performance.
  • 'disable': "One frame time" is more than acquisition_invalid_time.
  • 'enable': acquisition_invalid_time is ignored.
'default_parameter_set' 'factory', 'user_set1' Selects the kind of page of parameters to be loaded when camera is reset.
  • 'factory': Select the factory setting page.
  • 'user_set1': Select the 'user_set1' page.
'do_abort_grab' --- Aborts the current grab.
'do_save_parameter' --- Save the parameters to selected page by 'save_parameter_set'.
'do_strobe_out' --- Generates a strobe signal in applications by setting 'strobe_source' to 'strobe_software'. Strobe level is defined by the 'strobe_signal'.
'do_force_trigger' --- Forces an event trigger in applications by setting 'external_trigger' to 'true' and 'trigger_source' to 'software'.
'exposure_time' min ... max (float) Sets the exposure time in milliseconds.
'external_trigger' 'true', 'false' Enables/disables the trigger mode.
'gain' 0 ... 100 (long) Controls the gain as raw integer value. This is an amplification factor applied to the video signal.
'grab_timeout' 1 ... 32768 (long) Specifies the desired timeout for aborting a pending grab in milliseconds. Default : 5000.
'save_parameter_set' 'user_set1' Selects the kind of page to save the current parameter.
  • 'user_set1': Select the 'user_set1' page.
'start_async_after_grab_async' 'disable' , 'enable' By default, at the end of grab_image_async a new asynchronous grab command is automatically executed. If the parameter 'start_async_after_grab_async' is set to 'disable' this new grab command is omitted. Default: 'enable'.
'strobe_delay' 0.0 ... 9.174 (float) Used to delay the strobe signal in milliseconds.
'strobe_mode' 'off', 'timed', 'exposure_width' Specifies the operation mode of the strobe.
  • 'off': Disables the strobe.
  • 'timed': The strobe duration time is set using the 'strobe_time'.
  • 'exposure_width': The strobe duration time is set by the width of current frame or exposure pulse.
'strobe_signal' 'level_low', 'level_high' Specifies the activation mode of the strobe.
  • 'level_low': strobe signal is activated as low.
  • 'level_high': strobe signal is activated as high.
'strobe_source' 'strobe_out', 'strobe_software' Specifies the kind of source of strobe signal.
  • 'strobe_out': The strobe signal is generated by the 'strobe_mode'.
  • 'strobe_software': The strobe signal is generated by the software using 'do_strobe_out' function.
'strobe_time' 0.0 ... 9.174 (float) Sets the duration time of strobe signal in milliseconds when 'strobe_mode' is set as 'timed'.
'test_image' 'off', 'test_pattern' Specifies the type of image that is output by the camera.
  • 'off': Image is real and grabbed from the sensor.
  • 'test_pattern': Image is artificial pattern data, varying gradually from dark to bright.
'trigger_delay' 0.001 ... 1174.405 (float) Used to set the trigger delay time in microseconds. Received trigger is activated after this amount of delay.
'trigger_signal' 'falling', 'rising', 'level_low', 'level_high' Specifies the activation mode of the trigger.
  • 'falling': Trigger is considered as valid on the falling edge of the source signal.
  • 'rising': Trigger is considered as valid on the rising edge of the source signal.
  • 'level_low': Trigger is considered as valid as long as the level of the source signal is low.
  • 'level_high': Trigger is considered as valid as long as the level of the source signal is high.
'trigger_source' 'line1', 'software' Specifies the type of the trigger source when external_trigger is true.
  • 'line1': Trigger source will be physical line (or pin).
  • 'software': Trigger source will be the software using the 'do_software_trigger' function.
'volatile' 'enable', 'disable' Grayscale only. In the volatile mode the two image acquisition interface buffers are used directly to store HALCON images. This is the fastest mode to avoid copying raw images in memory. However, be aware that older images are overwritten again and again as a side-effect. Thus, you can only process one image while you grab another image. Older images are invalid! Default: 'disable'.

Parameters for get_framegrabber_param():

Additional parameters supported by get_framegrabber_param only. Note that all parameters supported by set_framegrabber_param can also be accessed by get_framegrabber_param. Furthermore, corresponding to the parameters supported by set_framegrabber_param, there may exist additional read-only parameters with the following postfixes:

  • '_description': These parameters provide the tooltip of the corresponding parameter as a string.
  • '_range': These parameters provide the minimum, maximum, stepwidth, and default values for the corresponding integer or float parameter as a tuple with 4 elements, e.g., get_framegrabber_param(..,'exposure_time_range',..) will return the output tuple [min,max,step,default]. Optionally, this tuple can also contain additional valid string values like 'auto' or 'manual'.
  • '_values': These parameters provide the valid value list for the corresponding parameter as a tuple, e.g., get_framegrabber_param(..,'volatile_values',..) will return the output tuple ['enable','disable'].
All these postfixed parameter names are not returned when calling info_framegrabber(..,'parameters',..) and are used to enable the easy parameterization via a generic graphical user interface, particularly the HDevelop Image Acquisition Assistant.

'device_firmware_version' firmware_version (string) Provides the version of the firmware in the camera.
'device_unique_id' device_full_id (string) Specifies the model name and serial number of the camera.
'image_available' 0, 1 (long) Used to check the status of last asycnhornous grab command. A value of '1' means that the image is already acquired.
'revision' revision (string) The revision number of the HALCON Crevis interface.
'sensor_type' sensor_type (string) Specifies the scan type of the sensor.

Release Notes

  • Revision 4.0 (May 27, 2009):
    • First official release.
    • Bugfixes in parameters 'exposure_time', 'strobe_delay', 'strobe_time', and 'trigger_delay'.
    • Renamed the parameters to keep the HALCON naming convention.
    • Add new parameters 'acquisition_invalid_time', 'continuous_grabbing', 'save_parameter_set', 'do_abort_grab', and 'start_async_after_grab_async'.
    • Added parameters with postfix '_description', '_range', and '_values' to enable the easy parameterization via a generic graphical user interface.

  • Revision 3.1 (Mar 02, 2009):
    • Bugfix in 'exposure_time' function, the exposure time value was not applied correctly (fixed in MCamU_Basic_V1.0.0.8).

  • Revision 3.0 (Feb 09, 2009):
    • First release.

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