Hardware triggered, continuous video acquisition with Basler GigE camera

I am using a Basler acA1300-60gm camera. I am able to acquire video using the matlab gigE drivers either with imaqtool, or directly through matlab. I can trigger the acquisition of a single frame with an external hardware trigger, but my problem is that I need to acquire multiple frames per hardware trigger, and am unable to do this.

The Basler proprietary drivers (which are now uninstalled, as per matlab gigE installation instructions) have an "AcquisitionMode" setting to switch between single frame and continuous mode. However, this property does not appear on the Imaqtool device properties, which I understood to mean that I cannot access it via matlab. Setting the vidobj.FramesPerTrigger to a value greater than one does not seem to have any effect. I was understanding this to mean that the camera is fixed in SingleFrame by the GigE controller, and that this overrides Matlab's FramesPerTrigger - could this be?

Below are my current camera settings.

If anyone has experience with continuous, triggered video acquisition through Matlab using a Basler gigE Camera, and has any thoughts/suggestions, they would be much appreciated. Am I missing an obvious way to access the AcquisitionMode parameter?

Many thanks in advance Iris

---------------- src =

   Display Summary for Video Source Object:

      General Settings:
        Parent = [1x1 videoinput]
        Selected = on
        SourceName = input1
        Tag = [0x0 string]
        Type = videosource

      Device Specific Properties:
        AcquisitionFrameRateAbs = 25
        AcquisitionFrameRateEnable = True
        AcquisitionStartTriggerActivation = RisingEdge
        AcquisitionStartTriggerDelayAbs = 0
        AcquisitionStartTriggerMode = On
        AcquisitionStartTriggerSource = Line1
        ActionCommandCount = 1
        ActionDeviceKey = 0
        ActionGroupKey = 0
        ActionGroupMask = 0
        ActionSelector = 1
        AllBlackLevelRaw = 0
        AllGainRaw = 0
        AnalogAllGainRaw = 0
        AOI1AutoFunctionAOIHeight = 1024
        AOI1AutoFunctionAOIOffsetX = 1
        AOI1AutoFunctionAOIOffsetY = 1
        AOI1AutoFunctionAOIUsageIntensity = True
        AOI1AutoFunctionAOIUsageWhiteBalance = False
        AOI1AutoFunctionAOIWidth = 1280
        AOI2AutoFunctionAOIHeight = 1024
        AOI2AutoFunctionAOIOffsetX = 1
        AOI2AutoFunctionAOIOffsetY = 1
        AOI2AutoFunctionAOIUsageIntensity = False
        AOI2AutoFunctionAOIUsageWhiteBalance = True
        AOI2AutoFunctionAOIWidth = 1280
        AutoExposureTimeAbsLowerLimit = 20
        AutoExposureTimeAbsUpperLimit = 350000
        AutoFunctionProfile = GainMinimum
        AutoGainRawLowerLimit = 0
        AutoGainRawUpperLimit = 95
        AutoTargetValue = 128
        BalanceWhiteAdjustmentDampingAbs = 0.97656
        BalanceWhiteAdjustmentDampingRaw = 1000
        BinningHorizontal = 1
        BinningModeHorizontal = Summing
        BinningModeVertical = Summing
        BinningVertical = 1
        CenterX = False
        CenterY = False
        Counter1CounterEventSource = FrameTrigger
        Counter1CounterResetSource = Off
        Counter2CounterEventSource = FrameStart
        Counter2CounterResetSource = Off
        DecimationHorizontal = 1
        DecimationVertical = 1
        DeviceFirmwareVersion = 106200-10;U;acA1300_60g;V3.15-6;0
        DeviceID = 21531505
        DeviceManufacturerInfo = none
        DeviceModelName = acA1300-60gm
        DeviceScanType = Areascan
        DeviceUserID = [0x0 string]
        DeviceVendorName = Basler
        DeviceVersion = 106200-10
        DigitalAllGainRaw = 0
        DigitalShift = 0
        ExpertFeature1_LegacyExpertFeatureAccessKey = 0
        ExpertFeature1_LegacyExpertFeatureEnable = False
        ExpertFeature1ExpertFeatureAccessKey = 0
        ExpertFeature1ExpertFeatureEnable = False
        ExpertFeature2ExpertFeatureAccessKey = 0
        ExpertFeature2ExpertFeatureEnable = False
        ExpertFeature3ExpertFeatureAccessKey = 0
        ExpertFeature3ExpertFeatureEnable = False
        ExpertFeature4ExpertFeatureAccessKey = 0
        ExpertFeature4ExpertFeatureEnable = False
        ExpertFeature5ExpertFeatureAccessKey = 0
        ExpertFeature5ExpertFeatureEnable = False
        ExpertFeature6ExpertFeatureAccessKey = 0
        ExpertFeature6ExpertFeatureEnable = False
        ExpertFeature7ExpertFeatureAccessKey = 0
        ExpertFeature7ExpertFeatureEnable = False
        ExposureAuto = Off
        ExposureMode = Timed
        ExposureTimeAbs = 5000
        ExposureTimeRaw = 5000
        FeatureSet = Full
        FileOpenMode = Read
        FrameStartTriggerActivation = RisingEdge
        FrameStartTriggerDelayAbs = 0
        FrameStartTriggerMode = Off
        FrameStartTriggerSource = Line1
        GainAuto = Off
        GainRemoveLimits = False
        Gamma = 1
        GammaEnable = False
        GammaSelector = User
        GrayValueAdjustmentDampingAbs = 0.68359
        GrayValueAdjustmentDampingRaw = 700
        LastError = InvalidParameter
        Line1LineDebouncerTimeAbs = 10
        Line1LineFormat = OptoCoupled
        Line1LineInverter = False
        Line1LineMode = Input
        Line1LineStatus = False
        Line1MinOutPulseWidthAbs = 0
        LineLogic = Negative
        LineStatusAll = 0
        Out1LineDebouncerTimeAbs = 0
        Out1LineFormat = OptoCoupled
        Out1LineInverter = False
        Out1LineMode = Output
        Out1LineSource = UserOutput
        Out1LineStatus = False
        Out1MinOutPulseWidthAbs = 0
        PacketDelay = 0
        PacketSize = 2000
        PixelColorFilter = None
        PixelDynamicRangeMax = 255
        PixelDynamicRangeMin = 0
        ReadoutTimeAbs = 14762
        ResultingFramePeriodAbs = 19810
        ResultingFrameRateAbs = 50.4796
        ReverseX = False
        SequenceAdvanceMode = Auto
        SequenceCurrentSet = 0
        SequenceEnable = False
        SequenceSetExecutions = 1
        SequenceSetIndex = 0
        SequenceSetTotalNumber = 2
        ShutterMode = Global
        SyncUserOutput1SyncUserOutputValue = False
        SyncUserOutputValueAll = 0
        TestImageSelector = Off
        TimestampTickFrequency = 125000000
        UserOutput1UserOutputValue = False
        UserOutputValueAll = 0
        Value1UserDefinedValue = 0
        Value2UserDefinedValue = 0
        Value3UserDefinedValue = 0
        Value4UserDefinedValue = 0
        Value5UserDefinedValue = 0
        VendorDefectPixelCorr = False

Answer 1

[Hanshin]

Hello Iris,

I recently started using the MATLAB Image acquisition toolbox and encountered a (I think) similar issue as yours. I use a AVT Gige camera and their SDK library has a C function to set the acquisition mode to 'continuous' like what you had in your camera. So, it is possible to let the camera stream continuously while I can pick most recent frame to display or process. I believe that the SDK automatically recycles image buffers so that the camera memory can be used efficiently. As you said, it appears that MATLAB's toolbox does not provide this functionality. Hope they do in the future. However MATLAB doesn't seem touching this parameter. It seems like MATLAB does not care about this parameter (perhaps overiding is the right term as you said).

For me, one way to get around this problem is to basically keep empty buffer(s) in the camera (or computer in case MATLAB?) memory by reading out image(s) from the buffer as soon as a frame is acquired. This is sort of like what the AVT SDK provided. A continuous acquisition is what I need to do anyway. So, what I did was to set up a 'FramesAcquiredFcn' call back function where it does 'getdata(obj,1)'. In this case, I needed to read out only the last frame (1) so that the total FramesAvailable is always 1 frame less than whatever maximum your memory allows (at which MATLAB flags an error). It appears that 'FramesAvailable' indicates how many frames are stored in the camera (or assigned computer) memory. With my current setting, MATLAB flags an error after reaching about 250 frames. In reality, I never got to the maximum frames even if I set 'FramesPerTrigger' to 'Inf'. Once 'start' is issued, the acquisition never stops until you issue 'stop' or the process is forced to stop for some reason. After stopping a continuous acquisition for about 4 min with the maximum frame rate of 17fps (~ 4000 frames), 'FramesAvailable' remained 0 (or 1 if stop happens before reading out) as expected (at least in my case).

Hopefully this is helpful for you.

Good luck! Hanshin

Answer 2

[Andrei]

AcquisitionFrameCount camera property value plays a role when using a hardware trigger configuration. It's likely this is set by default to 1 when the camera is powered on.

In more recent MATLAB releases (since R2016a), you can set the AcquisitionFrameCount property to a desired value.