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hasNextMessage

Check if Ibeo Data Container (IDC) file selection has next message

Description

example

flag = hasNextMessage(msgReader) checks if the IDC file selection has a subsequent message to read. This object function returns true if there is a next message available to read from the ibeoMessageReader object, msgReader. Otherwise, it returns false.

Examples

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Create an ibeoFileReader object, ibeoReader, to read the message headers from the IDC file. Replace the placeholder argument sample_data.idc with the name of your IDC file as sample_data.idc file is not provided with the toolbox.

ibeoReader = ibeoFileReader('sample_data.idc')
ibeoReader =
 
  ibeoFileReader with properties:
 
       FileName: "C:/Documents/MATLAB/ibeo_data/sample_data.idc"
      StartTime: 15-Mar-2020 11:21:04.999434999
        EndTime: 15-Mar-2020 11:25:35.030095000
       Duration: 00:04:30
    FileSummary: CAN             53    msgs [0x1002]
                 scan            53    msgs [0x2205]
                 object          106   msgs [0x2281]
                 image           53    msgs [0x2403]
                 vehicleState    53    msgs [0x2808]
                 measurementList 53    msgs [0x2821]
                 pointCloudPlane 53    msgs [0x7510]
                 unsupported     53    msgs [0x6120]
                 unsupported     53    msgs [0x6970]

Create an ibeoMessageReader object, imgReader, to read all images in the first 2 minutes, by using the select function with appropriate message type and time range values.

timeRange = [0, minutes(2)];
imgReader = select(ibeoReader, 'image', timeRange);

Visualize the message data by reading the messages one at a time to a video player object. First, create a vision.VideoPlayer object. Then, use the hasNextMessage function to check whether imgReader contains a message after the current one. If it does, use readNextMessage function to read the images into the workspace.

videoPlayer = vision.VideoPlayer;
while hasNextMessage(imgReader)
    img = readNextMessage(imgReader);
    step(videoPlayer,img);
end
release(videoPlayer);
     

Reset the ibeoMessageReader object, imgReader, to the first message in the selection, using the reset function.

 reset(imgReader);

Input Arguments

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Message reader, specified as a ibeoMessageReader object.

Output Arguments

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File selection has subsequent message to read, returned as a logical true or false.

Version History

Introduced in R2021a