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deleteFile

Delete file on target hardware

Description

example

deleteFile(mypi,filename) deletes the specified file from the target hardware.

Examples

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You can delete a file on the Raspberry Pi® hardware.

deleteFile(mypi,'/home/pi/cap.jpg')

You can delete multiple files on the Raspberry Pi hardware using a wildcard character, *.

deleteFile(mypi,'/home/pi/*.jpg') 

You can delete files on the Raspberry Pi hardware when connected to it from MATLAB® Online™. To use your hardware from MATLAB Online, follow the instructions in Connect to Raspberry Pi Hardware Board in MATLAB Online.

When connected to your hardware from MATLAB Online, the default working directory is /home/matlabrpi, instead of /home/pi. This is the only directory you can delete files from. Delete a file in /home/matlabrpi by using the file name as an input argument.

deleteFile(mypi,'myvideo.h264')

Create a connection from the MATLAB to the Raspberry Pi board. If you encounter errors after running the above command, try using additional arguments (as listed in raspi) or refer to Troubleshoot Connecting Issues to Raspberry Pi Hardware.

mypi = raspi;

Create a connection, mycam, from the MATLAB software to the camera board on the Raspberry Pi hardware, and set the image resolution. The connection displays the camera board properties.

mycam = cameraboard(mypi,"Resolution","1280x720")
mycam = 

Cameraboard with Properties:

                    Name: Camera Board   
              Resolution: "1280x720"       (View available resolutions)
                 Quality: 10              (1 to 100)
                Rotation: 0               (0, 90, 180 or 270)
          HorizontalFlip: 0              
            VerticalFlip: 0              
               FrameRate: 30              (2 to 30)
               Recording: 0              

   Picture Settings
              Brightness: 50              (0 to 100)
                Contrast: 0               (-100 to 100)
              Saturation: 0               (-100 to 100)
               Sharpness: 0               (-100 to 100)

   Exposure and AWB
            ExposureMode: "auto"          (View available exposure modes)
    ExposureCompensation: 0               (-10 to 10)
                 AWBMode: "auto"          (View available AWB modes)
            MeteringMode: "average"       (View available metering modes)

   Effects
             ImageEffect: "none"          (View available image effects)
      VideoStabilization: "off"          
                     ROI: [0.00 0.00 1.00 1.00] (0.0 to 1.0 [top, left, width, height])

Capture and display a sequence of 10 snapshots on your computer.

for ii = 1:10
img = snapshot(mycam);
    imagesc(img)
    drawnow
end

Each of the 10 snapshots is the latest image captured by the camera.

If the image is upside down, change its orientation.

mycam.Rotation = 180

You can use the same approach to change the values of other cameraboard properties.

Record a 60 second video.

record(mycam,"myvideo.h264",60)

Stop the recording immediately.

stop(mycam)

Copy the video from the board to your computer.

getFile(mypi,"myvideo.h264","C:\MATLAB")

Delete the video file from the hardware to free up space.

deleteFile(mypi,"myvideo.h264")

Input Arguments

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Connection to the Raspberry Pi hardware board, specified as a raspi object.

File to delete, specified as a string. You can delete a file on the Raspberry Pi hardware. When you specify the file name, you can use path information and wildcards. In MATLAB Online, you can only delete files in the default working directory, /home/matlabrpi.

Example: '/home/pi/cap.jpg'

Example: '/home/pi/*.jpg'

Example: 'myvideo.h264'

Data Types: cell