Advanced Property Support

The Image Acquisition Toolbox™ has added GenICam™ property enhancements for the GigE Vision^®(gige) and GenICam GenTL (gentl) adaptors used with thevideoinputobject in R2016a. These features were already included in thegigecamobject.

Change Properties While the Acquisition Is Running

This ability is useful for properties that you want to change dynamically, such as exposure time. For example, you can now do this:

% Create the videoinput object using the GigE adaptor vid = videoinput('gige') % Get the video source src = getselectedsource(vid); % Set the frames per trigger on the source vid.FramesPerTrigger = Inf; % Start acquiring frames start(vid) % Change the exposure time during the acquisition src.ExposureTime = 4;

以前,改变曝光时间后开始ing the acquisition resulted in an error.

Dynamic Accessibility and Readability

Device-specific properties, or camera GenICam properties, are now dynamically accessible. In previous releases, camera GenICam properties that were not accessible were hidden. If you display the device-specific properties using thedisp,getorpropinfofunctions, properties that previously did not show up now show up with labels.

Thepropinfofunction includes a new field calledAccessible, which is a read-only boolean property. Adispon a property that hasAccessibleset to0results in “Currently not accessible.” To enable accessibility, setAccessibleto1. For example, if you have theReverseYproperty set toAccessible, the following:

propinfo(src,'ReverseY')

would result in a disp showing:

Accessible: 1

The same is true for theReadOnlyproperty. Readability is now dynamic and thepropinfofunction shows aReadOnlyproperty as either'notCurrently', if it is writable, or'currently', if it is read-only. The example in the Dynamic Constraints section demonstrates the dynamic use of this property.

You can view the source properties to see if any properties are currently not accessible. In this example, for the part of the disp shown below,AcquisitionFrameCountandBalanceRatioRaware currently not accessible.

>> src = vid.Source src = Display Summary for Video Source Object: General Settings: Parent = [1x1 videoinput] Selected = on SourceName = input1 Tag = [0x0 character vector] Type = videosource Device Specific Properties: AcquisitionFrameCount = (Currently not accessible) AcquisitionFrameRate = 4.5 AcquisitionFrameRateAuto = Off AcquisitionFrameRateEnabled = True BalanceRatioRaw = (Currently not accessible) BinningHorizontal = 1 BinningVertical = 1 BlackLevel = 1.001 ...

Dynamic Constraints

If you change a property that results in a change of possible values, or constraint change, for another property, the other property’s constraint values are updated dynamically. Consider a camera that has an automatic sharpness setting that you can set toContinuousto automatically adjust the sharpness or set toOff. The automatic sharpness property then affects the relatedSharpnessproperty. In this example, whenSharpnessAutois set toContinuous, a disp of theSharpnessproperty shows the constrained values and that it is not able to be set.

>> propinfo(src, 'SharpnessAuto') ans = Type: 'character vector' Constraint: 'enum' ConstraintValue: {'Continuous' 'Off'} DefaultValue: 'Continuous' ReadOnly: 'notCurrently' DeviceSpecific: 1 Accessible: 1 >> propinfo(src, 'Sharpness') ans = Type: 'integer' Constraint: 'bounded' ConstraintValue: [1532 1532] DefaultValue: 1532 ReadOnly: 'currently' DeviceSpecific: 1 Accessible: 1

If you then set theSharpnessAutoproperty toOff, a second disp of theSharpnessproperty shows that the constrained values have dynamically updated, and that it is now able to be set (no longer read-only).

>> src.SharpnessAuto = 'Off' >> propinfo(src, 'Sharpness') ans = Type: 'integer' Constraint: 'bounded' ConstraintValue: [0 4095] DefaultValue: 1532 ReadOnly: 'notCurrently' DeviceSpecific: 1 Accessible: 1

Grouped Selector Properties

In both theImage Acquisition Explorerand the command line, selector properties are now grouped. In the tool, you can see the groupings in theDevice Propertiestab. In the property display on the command line, the related properties are grouped – the selector property is listed, with its possible values appearing below it.

For example, in previous versions of the toolbox, for aGainSelectorwith possible values ofRed,Blue, andGreenand aGainproperty, the gain properties displayed as follows:

>> vid = videoinput('gige') >> src = getselectedsource(vid) ... ... RedGain = 0.4 BlueGain = 0.2 GreenGain = 0.1 ...

They now display as separate values on one selector property instead:

>> vid = videoinput('gige') >> src = getselectedsource(vid) ... ... GainSelector = 'Red' Gain = 0.2 ...

Compatibility Considerations

The grouping of selector properties results in a compatibility consideration starting in R2016a because of the change in how selector properties are displayed, read, or written. There are now fewer properties since some are shown as a single selector property with separate values, whereas they used to be separate properties.

If you have any MATLAB^®code written prior to R2016a which references the previous, separate properties, you need to change the code to reflect them as values on the selector property. Setting and getting properties that belong to a selector using the previous composite-name style is no longer supported. For example,RedGainno longer works. Instead useGainSelectorset toRed, as shown in the example.

To set a property value, first set the selector value, then set the property value:

src.GainSelector = 'Green'; src.Gain = 0.1;