MATLAB/Octave - Thermal Imaging Bricklet

This is the description of the MATLAB/Octave API bindings for the Thermal Imaging Bricklet. General information and technical specifications for the Thermal Imaging Bricklet are summarized in its hardware description.

An installation guide for the MATLAB/Octave API bindings is part of their general description.

Examples

The example code below is Public Domain (CC0 1.0).

Callback (MATLAB)

Download (matlab_example_callback.m)

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function matlab_example_callback()
    import com.tinkerforge.IPConnection;
    import com.tinkerforge.BrickletThermalImaging;

    HOST = 'localhost';
    PORT = 4223;
    UID = 'XYZ'; % Change XYZ to the UID of your Thermal Imaging Bricklet

    ipcon = IPConnection(); % Create IP connection
    ti = handle(BrickletThermalImaging(UID, ipcon), 'CallbackProperties'); % Create device object

    ipcon.connect(HOST, PORT); % Connect to brickd
    % Don't use device before ipcon is connected

    % Register high contrast image callback to function cb_high_contrast_image
    set(ti, 'HighContrastImageCallback', @(h, e) cb_high_contrast_image(e));

    % Enable high contrast image transfer for callback
    ti.setImageTransferConfig(BrickletThermalImaging.IMAGE_TRANSFER_CALLBACK_HIGH_CONTRAST_IMAGE);

    input('Press key to exit\n', 's');
    ipcon.disconnect();
end

% Callback function for high contrast image callback
function cb_high_contrast_image(e)
    % e.image is a array of size 80*60 with 8 bit grey value for each element
end

Create Image (MATLAB)

Download (matlab_example_create_image.m)

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function matlab_example_create_image()
  import java.io.File;
  import javax.imageio.ImageIO;
  import com.tinkerforge.IPConnection;
  import java.awt.image.BufferedImage;
  import com.tinkerforge.BrickletThermalImaging;

  % Takes one thermal image and saves it as PNG

  HOST = 'localhost';
  PORT = 4223;
  UID = 'XYZ'; % Change XYZ to the UID of your Thermal Imaging Bricklet

  WIDTH = 80;
  HEIGHT = 60;
  SCALE = 10;

  % Creates standard thermal image color palette (blue=cold, red=hot)
  paletteR = zeros(1, 255, 'int32');
  paletteG = zeros(1, 255, 'int32');
  paletteB = zeros(1, 255, 'int32');

  function createThermalImageColorPalette()
    for x = 1:1:255
      paletteR(x) = int32(fix(255 * sqrt(x / 255)));
      paletteG(x) = int32(fix(255 * (x / 255)^3));
      paletteB(x) = 0;

      paletteBSine = sin(2 * pi * (x / 255));

      if paletteBSine >= 0
        paletteB(x) = int32(fix(255 * sin(2 * pi * (x / 255))));
      end
    end
  end

  % Helper function for simple buffer resize
  function resizedBufferedImage = resize(sourceBufferedImage, newW, newH)
    import java.awt.Image;
    import java.awt.image.BufferedImage;

    scaledSourceBufferedImage = sourceBufferedImage.getScaledInstance(newW, ...
                                                                      newH, ...
                                                                      Image.SCALE_SMOOTH);
    resizedBufferedImage = BufferedImage(newW, newH, BufferedImage.TYPE_INT_ARGB);

    g2d = resizedBufferedImage.createGraphics();
    g2d.drawImage(scaledSourceBufferedImage, 0, 0, []);
    g2d.dispose();
  end

  ipcon = IPConnection(); % Create IP connection
  ti = handle(BrickletThermalImaging(UID, ipcon), 'CallbackProperties'); % Create device object

  ipcon.connect(HOST, PORT); % Connect to brickd
  % Do not use device before ipcon is connected

  % Enable high contrast image transfer for getter
  ti.setImageTransferConfig(BrickletThermalImaging.IMAGE_TRANSFER_MANUAL_HIGH_CONTRAST_IMAGE);

  createThermalImageColorPalette();

  % If we change between transfer modes we have to wait until one more
  % image is taken after the mode is set and the first image is saved
  % we can call get_high_contrast_image any time.
  pause on;
  pause(0.5);

  image = typecast(ti.getHighContrastImage(), 'int32');

  % Use palette mapping to create thermal image coloring
  for i = 1:1:4800
    % Because in MATLAB/Octave indexing starts from 1
    if image(i) < 255
      image(i) = image(i) + 1;
    end

    alphaLSH = uint32(bitshift(255, 24));
    redLSH = uint32(bitshift(paletteR(image(i)), 16));
    greenLSH = uint32(bitshift(paletteG(image(i)), 8));
    blueLSH = uint32(bitshift(paletteB(image(i)), 0));

    image(i) = typecast(bitor(bitor(alphaLSH, redLSH), bitor(greenLSH, blueLSH)), ...
                        'int32');
  end

  % Create BufferedImage with data
  bufferedImage = BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_ARGB);
  bufferedImage.setRGB(0, 0, WIDTH, HEIGHT, image, 0, WIDTH);

  % Scale to 800x600 and save thermal image!
  ImageIO.write(resize(bufferedImage, WIDTH*SCALE, HEIGHT*SCALE), 'png', File('thermal_image.png'));

  input('Press key to exit\n', 's');

  ipcon.disconnect();
end

Live Video (MATLAB)

Download (matlab_example_live_video.m)

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function matlab_example_live_video()
  import java.awt.*;
  import javax.swing.*;
  import java.awt.Image;
  import javax.swing.BoxLayout;
  import javax.swing.ImageIcon;
  import java.awt.event.WindowEvent;
  import com.tinkerforge.IPConnection;
  import java.awt.image.BufferedImage;
  import com.tinkerforge.BrickletThermalImaging;

  % Shows live thermal image video in in swing label

  HOST = 'localhost';
  PORT = 4223;
  UID = 'XYZ'; % Change XYZ to the UID of your Thermal Imaging Bricklet

  WIDTH = 80;
  HEIGHT = 60;
  SCALE = 5;

% Creates standard thermal image color palette (blue=cold, red=hot)
  paletteR = zeros(1, 255, 'int32');
  paletteG = zeros(1, 255, 'int32');
  paletteB = zeros(1, 255, 'int32');

  function createThermalImageColorPalette()
    for x = 1:1:255
      paletteR(x) = int32(fix(255 * sqrt(x / 255)));
      paletteG(x) = int32(fix(255 * (x / 255)^3));
      paletteB(x) = 0;

      paletteBSine = sin(2 * pi * (x / 255));

      if paletteBSine >= 0
        paletteB(x) = int32(fix(255 * sin(2 * pi * (x / 255))));
      end
    end
  end

  % Function to handle example exit
  function end_example()
      ipcon.disconnect();
      frameExample.hide();
  end

  ipcon = IPConnection(); % Create IP connection
  ti = handle(BrickletThermalImaging(UID, ipcon), 'CallbackProperties'); % Create device object

  ipcon.connect(HOST, PORT); % Connect to brickd
  % Do not use device before ipcon is connected

  % Enable high contrast image transfer for callback
  ti.setImageTransferConfig(BrickletThermalImaging.IMAGE_TRANSFER_CALLBACK_HIGH_CONTRAST_IMAGE);

  createThermalImageColorPalette();

  % If we change between transfer modes we have to wait until one more
  % image is taken after the mode is set and the first image is saved
  % we can call get_high_contrast_image any time.
  pause on;
  pause(0.5);

  % Prepare the JPanel and the JFrame
  panelExample = JPanel();
  frameExample = JFrame('Example Live Video');

  set(frameExample, 'WindowClosingCallback', @(h, e) end_example());
  frameExample.setSize(WIDTH*SCALE, HEIGHT*SCALE);
  panelExample.setLayout(BoxLayout(panelExample, BoxLayout.Y_AXIS));

  % Prepare JLabel
  bufferedImage = BufferedImage(80, 60, BufferedImage.TYPE_INT_ARGB);

  newW = WIDTH*SCALE;
  newH = HEIGHT*SCALE;
  scaledSourceBufferedImage = bufferedImage.getScaledInstance(newW, ...
                                                              newH, ...
                                                              Image.SCALE_SMOOTH);
  resizedBufferedImage = BufferedImage(newW, newH, BufferedImage.TYPE_INT_ARGB);
  g2d = resizedBufferedImage.createGraphics();
  g2d.drawImage(scaledSourceBufferedImage, 0, 0, []);
  g2d.dispose();

  labelExample = JLabel(ImageIcon(resizedBufferedImage));
  labelExample.setAlignmentX(Component.CENTER_ALIGNMENT);

  % Populate the layout
  panelExample.add(labelExample);

  frameExample.getContentPane().add(panelExample);
  frameExample.pack();
  frameExample.show();

  % Register high contrast image callback to function cb_high_contrast_image
  set(ti, 'HighContrastImageCallback', @(h, e) cb_high_contrast_image(e, ...
                                                                      paletteR, ...
                                                                      paletteG, ...
                                                                      paletteB, ...
                                                                      WIDTH, ...
                                                                      HEIGHT, ...
                                                                      SCALE, ...
                                                                      labelExample));
end

% Callback function for high contrast image callback
function cb_high_contrast_image(e, ...
                                paletteR, ...
                                paletteG, ...
                                paletteB, ...
                                WIDTH, ...
                                HEIGHT, ...
                                SCALE, ...
                                labelExample)
    import java.awt.Image;
    import javax.swing.JLabel;
    import javax.swing.ImageIcon;
    import java.awt.image.BufferedImage;

    image = typecast(e.image, 'int32');

    % Use palette mapping to create thermal image coloring
    for i = 1:1:4800
      % Because in MATLAB/Octave indexing starts from 1
      if image(i) < 255
        image(i) = image(i) + 1;
      end

      alphaLSH = uint32(bitshift(255, 24));
      redLSH = uint32(bitshift(paletteR(image(i)), 16));
      greenLSH = uint32(bitshift(paletteG(image(i)), 8));
      blueLSH = uint32(bitshift(paletteB(image(i)), 0));

      image(i) = typecast(bitor(bitor(alphaLSH, redLSH), bitor(greenLSH, blueLSH)), ...
                          'int32');
    end

    % Create BufferedImage with data
    bufferedImage = BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_ARGB);
    bufferedImage.setRGB(0, 0, WIDTH, HEIGHT, image, 0, WIDTH);

    % Simple buffer resize
    newW = WIDTH*SCALE;
    newH = HEIGHT*SCALE;
    scaledSourceBufferedImage = bufferedImage.getScaledInstance(newW, ...
                                                                newH, ...
                                                                Image.SCALE_SMOOTH);
    resizedBufferedImage = BufferedImage(newW, newH, BufferedImage.TYPE_INT_ARGB);
    g2d = resizedBufferedImage.createGraphics();
    g2d.drawImage(scaledSourceBufferedImage, 0, 0, []);
    g2d.dispose();

    % Set resized buffered image as icon of label. Change SCALE to change the
    % size of the video
    labelExample.setIcon(ImageIcon(resizedBufferedImage));
end

Callback (Octave)

Download (octave_example_callback.m)

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function octave_example_callback()
    more off;

    HOST = "localhost";
    PORT = 4223;
    UID = "XYZ"; % Change XYZ to the UID of your Thermal Imaging Bricklet

    ipcon = javaObject("com.tinkerforge.IPConnection"); % Create IP connection
    ti = javaObject("com.tinkerforge.BrickletThermalImaging", UID, ipcon); % Create device object

    ipcon.connect(HOST, PORT); % Connect to brickd
    % Don't use device before ipcon is connected

    % Register high contrast image callback to function cb_high_contrast_image
    ti.addHighContrastImageCallback(@cb_high_contrast_image);

    % Enable high contrast image transfer for callback
    ti.setImageTransferConfig(ti.IMAGE_TRANSFER_CALLBACK_HIGH_CONTRAST_IMAGE);

    input("Press key to exit\n", "s");
    ipcon.disconnect();
end

% Callback function for high contrast image callback
function cb_high_contrast_image(e)
    % e.image is a array of size 80*60 with 8 bit grey value for each element
end

Create Image (Octave)

Download (octave_example_create_image.m)

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function octave_example_create_image()
  more off;

  % Takes one thermal image and saves it as PNG

  HOST = "localhost";
  PORT = 4223;
  UID = "XYZ"; % Change XYZ to the UID of your Thermal Imaging Bricklet

  WIDTH = 80;
  HEIGHT = 60;
  SCALE = 10;

  ipcon = javaObject("com.tinkerforge.IPConnection"); % Create IP connection
  ti = javaObject("com.tinkerforge.BrickletThermalImaging", UID, ipcon); % Create device object

  % Creates standard thermal image color palette (blue=cold, red=hot)
  paletteR = zeros(1, 255, "int32");
  paletteG = zeros(1, 255, "int32");
  paletteB = zeros(1, 255, "int32");

  function createThermalImageColorPalette()
    for x = 1:1:255
      paletteR(x) = int32(fix(255 * sqrt(x / 255)));
      paletteG(x) = int32(fix(255 * (x / 255)^3));
      paletteB(x) = 0;

      paletteBSine = sin(2 * pi * (x / 255));

      if paletteBSine >= 0
        paletteB(x) = int32(fix(255 * sin(2 * pi * (x / 255))));
      end
    end
  end

  % Helper function for simple buffer resize
  function resizedBufferedImage = resize(sourceBufferedImage, newW, newH)
    scaledSourceBufferedImage = sourceBufferedImage.getScaledInstance(newW, ...
                                                                      newH, ...
                                                                      java_get("java.awt.Image", "SCALE_SMOOTH"));
    resizedBufferedImage = javaObject("java.awt.image.BufferedImage", ...
                                      newW, ...
                                      newH, ...
                                      java_get("java.awt.image.BufferedImage", "TYPE_INT_ARGB"));
    g2d = resizedBufferedImage.createGraphics();
    g2d.drawImage(scaledSourceBufferedImage, 0, 0, []);
    g2d.dispose();
  end

  ipcon.connect(HOST, PORT); % Connect to brickd
  % Do not use device before ipcon is connected

  % Enable high contrast image transfer for getter
  ti.setImageTransferConfig(java_get("com.tinkerforge.BrickletThermalImaging", ...
                                     "IMAGE_TRANSFER_MANUAL_HIGH_CONTRAST_IMAGE"));

  createThermalImageColorPalette();

  % If we change between transfer modes we have to wait until one more
  % image is taken after the mode is set and the first image is saved
  % we can call get_high_contrast_image any time.
  pause(0.5);

  image = typecast(ti.getHighContrastImage(), "int32");

  % Use palette mapping to create thermal image coloring
  for i = 1:1:4800
    % Because in MATLAB/Octave indexing starts from 1
    if image(i) < 255
      image(i) = image(i) + 1;
    end

    alphaLSH = uint32(bitshift(255, 24));
    redLSH = uint32(bitshift(paletteR(image(i)), 16));
    greenLSH = uint32(bitshift(paletteG(image(i)), 8));
    blueLSH = uint32(bitshift(paletteB(image(i)), 0));

    image(i) = typecast(bitor(bitor(alphaLSH, redLSH), bitor(greenLSH, blueLSH)), ...
                        "int32");
  end

  % Create BufferedImage with data
  bufferedImage = javaObject("java.awt.image.BufferedImage", ...
                             WIDTH, ...
                             HEIGHT, ...
                             java_get("java.awt.image.BufferedImage", "TYPE_INT_ARGB"));

  bufferedImage.setRGB(0, 0, WIDTH, HEIGHT, image, 0, WIDTH);

  % Scale to 800x600 and save thermal image!
  javaMethod("write", ...
             "javax.imageio.ImageIO", ...
             resize(bufferedImage, WIDTH*SCALE, HEIGHT*SCALE), ...
             "png", ...
             javaObject("java.io.File", "thermal_image.png"));

  input("Press key to exit\n", "s");

  ipcon.disconnect();
end

API

Generally, every method of the MATLAB bindings that returns a value can throw a TimeoutException. This exception gets thrown if the device did not respond. If a cable based connection is used, it is unlikely that this exception gets thrown (assuming nobody unplugs the device). However, if a wireless connection is used, timeouts will occur if the distance to the device gets too big.

Beside the TimeoutException there is also a NotConnectedException that is thrown if a method needs to communicate with the device while the IP Connection is not connected.

Since the MATLAB bindings are based on Java and Java does not support multiple return values and return by reference is not possible for primitive types, we use small classes that only consist of member variables. The member variables of the returned objects are described in the corresponding method descriptions.

The package for all Brick/Bricklet bindings and the IP Connection is com.tinkerforge.*

All methods listed below are thread-safe.

Basic Functions

public class BrickletThermalImaging(String uid, IPConnection ipcon)

Creates an object with the unique device ID uid.

In MATLAB:

import com.tinkerforge.BrickletThermalImaging;

thermalImaging = BrickletThermalImaging('YOUR_DEVICE_UID', ipcon);

In Octave:

thermalImaging = java_new("com.tinkerforge.BrickletThermalImaging", "YOUR_DEVICE_UID", ipcon);

This object can then be used after the IP Connection is connected (see examples above).

public int[] getHighContrastImage()

Returns the current high contrast image. See here for the difference between High Contrast and Temperature Image. If you don't know what to use the High Contrast Image is probably right for you.

The data is organized as a 8-bit value 80x60 pixel matrix linearized in a one-dimensional array. The data is arranged line by line from top left to bottom right.

Each 8-bit value represents one gray-scale image pixel that can directly be shown to a user on a display.

Before you can use this function you have to enable it with setImageTransferConfig().

public int[] getTemperatureImage()

Returns the current temperature image. See here for the difference between High Contrast and Temperature Image. If you don't know what to use the High Contrast Image is probably right for you.

The data is organized as a 16-bit value 80x60 pixel matrix linearized in a one-dimensional array. The data is arranged line by line from top left to bottom right.

Each 16-bit value represents one temperature measurement in either Kelvin/10 or Kelvin/100 (depending on the resolution set with:matlab:func:setResolution() <BrickletThermalImaging::setResolution>).

Before you can use this function you have to enable it with setImageTransferConfig().

public BrickletThermalImaging.Statistics getStatistics()

Returns the spotmeter statistics, various temperatures, current resolution and status bits.

The spotmeter statistics are:

  • Index 0: Mean Temperature.
  • Index 1: Maximum Temperature.
  • Index 2: Minimum Temperature.
  • Index 3: Pixel Count of spotmeter region of interest.

The temperatures are:

  • Index 0: Focal Plain Array temperature.
  • Index 1: Focal Plain Array temperature at last FFC (Flat Field Correction).
  • Index 2: Housing temperature.
  • Index 3: Housing temperature at last FFC.

The resolution is either 0 to 6553 Kelvin or 0 to 655 Kelvin. If the resolution is the former, the temperatures are in Kelvin/10, if it is the latter the temperatures are in Kelvin/100.

FFC (Flat Field Correction) Status:

  • FFC Never Commanded: Only seen on startup before first FFC.
  • FFC Imminent: This state is entered 2 seconds prior to initiating FFC.
  • FFC In Progress: Flat field correction is started (shutter moves in front of lens and back). Takes about 1 second.
  • FFC Complete: Shutter is in waiting position again, FFC done.

Temperature warning bits:

  • Index 0: Shutter lockout (if true shutter is locked out because temperature is outside -10°C to +65°C)
  • Index 1: Overtemperature shut down imminent (goes true 10 seconds before shutdown)

The following constants are available for this function:

  • BrickletThermalImaging.RESOLUTION_0_TO_6553_KELVIN = 0
  • BrickletThermalImaging.RESOLUTION_0_TO_655_KELVIN = 1
  • BrickletThermalImaging.FFC_STATUS_NEVER_COMMANDED = 0
  • BrickletThermalImaging.FFC_STATUS_IMMINENT = 1
  • BrickletThermalImaging.FFC_STATUS_IN_PROGRESS = 2
  • BrickletThermalImaging.FFC_STATUS_COMPLETE = 3

The returned object has the public member variables int[] spotmeterStatistics, int[] temperatures, int resolution, int ffcStatus and boolean[] temperatureWarning.

public void setResolution(int resolution)

Sets the resolution. The Thermal Imaging Bricklet can either measure

  • from 0 to 6553 Kelvin (-273.15°C to +6279.85°C) with 0.1°C resolution or
  • from 0 to 655 Kelvin (-273.15°C to +381.85°C) with 0.01°C resolution.

The accuracy is specified for -10°C to 450°C in the first range and -10°C and 140°C in the second range.

The default value is 0 to 655 Kelvin.

The following constants are available for this function:

  • BrickletThermalImaging.RESOLUTION_0_TO_6553_KELVIN = 0
  • BrickletThermalImaging.RESOLUTION_0_TO_655_KELVIN = 1
public int getResolution()

Returns the resolution as set by setResolution().

The following constants are available for this function:

  • BrickletThermalImaging.RESOLUTION_0_TO_6553_KELVIN = 0
  • BrickletThermalImaging.RESOLUTION_0_TO_655_KELVIN = 1
public void setSpotmeterConfig(int[] regionOfInterest)

Sets the spotmeter region of interest. The 4 values are

  • Index 0: Column start (has to be smaller then Column end).
  • Index 1: Row start (has to be smaller then Row end).
  • Index 2: Column end (has to be smaller then 80).
  • Index 3: Row end (has to be smaller then 60).

The spotmeter statistics can be read out with getStatistics().

The default region of interest is (39, 29, 40, 30).

public int[] getSpotmeterConfig()

Returns the spotmeter config as set by setSpotmeterConfig().

public void setHighContrastConfig(int[] regionOfInterest, int dampeningFactor, int[] clipLimit, int emptyCounts)

Sets the high contrast region of interest, dampening factor, clip limit and empty counts. This config is only used in high contrast mode (see setImageTransferConfig()).

The high contrast region of interest consists of four values:

  • Index 0: Column start (has to be smaller or equal then Column end).
  • Index 1: Row start (has to be smaller then Row end).
  • Index 2: Column end (has to be smaller then 80).
  • Index 3: Row end (has to be smaller then 60).

The algorithm to generate the high contrast image is applied to this region.

Dampening Factor: This parameter is the amount of temporal dampening applied to the HEQ (history equalization) transformation function. An IIR filter of the form:

(N / 256) * previous + ((256 - N) / 256) * current

is applied, and the HEQ dampening factor represents the value N in the equation, i.e., a value that applies to the amount of influence the previous HEQ transformation function has on the current function. The lower the value of N the higher the influence of the current video frame whereas the higher the value of N the more influence the previous damped transfer function has.

Clip Limit Index 0 (AGC HEQ Clip Limit Low): This parameter defines an artificial population that is added to every non-empty histogram bin. In other words, if the Clip Limit Low is set to L, a bin with an actual population of X will have an effective population of L + X. Any empty bin that is nearby a populated bin will be given an artificial population of L. The effect of higher values is to provide a more linear transfer function; lower values provide a more non-linear (equalized) transfer function.

Clip Limit Index 1 (AGC HEQ Clip Limit High): This parameter defines the maximum number of pixels allowed to accumulate in any given histogram bin. Any additional pixels in a given bin are clipped. The effect of this parameter is to limit the influence of highly-populated bins on the resulting HEQ transformation function.

Empty Counts: This parameter specifies the maximum number of pixels in a bin that will be interpreted as an empty bin. Histogram bins with this number of pixels or less will be processed as an empty bin.

The default values are

  • Region Of Interest = (0, 0, 79, 59),
  • Dampening Factor = 64,
  • Clip Limit = (4800, 512) and
  • Empty Counts = 2.
public BrickletThermalImaging.HighContrastConfig getHighContrastConfig()

Returns the high contrast config as set by setHighContrastConfig().

The returned object has the public member variables int[] regionOfInterest, int dampeningFactor, int[] clipLimit and int emptyCounts.

Advanced Functions

public int[] getAPIVersion()

Returns the version of the API definition (major, minor, revision) implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.

public boolean getResponseExpected(int functionId)

Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.

For getter functions this is enabled by default and cannot be disabled, because those functions will always send a response. For callback configuration functions it is enabled by default too, but can be disabled by setResponseExpected(). For setter functions it is disabled by default and can be enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

See setResponseExpected() for the list of function ID constants available for this function.

public void setResponseExpected(int functionId, boolean responseExpected)

Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and callback configuration functions (default value: true). For getter functions it is always enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

The following function ID constants are available for this function:

  • BrickletThermalImaging.FUNCTION_SET_RESOLUTION = 4
  • BrickletThermalImaging.FUNCTION_SET_SPOTMETER_CONFIG = 6
  • BrickletThermalImaging.FUNCTION_SET_HIGH_CONTRAST_CONFIG = 8
  • BrickletThermalImaging.FUNCTION_SET_IMAGE_TRANSFER_CONFIG = 10
  • BrickletThermalImaging.FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • BrickletThermalImaging.FUNCTION_SET_STATUS_LED_CONFIG = 239
  • BrickletThermalImaging.FUNCTION_RESET = 243
  • BrickletThermalImaging.FUNCTION_WRITE_UID = 248
public void setResponseExpectedAll(boolean responseExpected)

Changes the response expected flag for all setter and callback configuration functions of this device at once.

public BrickletThermalImaging.SPITFPErrorCount getSPITFPErrorCount()

Returns the error count for the communication between Brick and Bricklet.

The errors are divided into

  • ACK checksum errors,
  • message checksum errors,
  • framing errors and
  • overflow errors.

The errors counts are for errors that occur on the Bricklet side. All Bricks have a similar function that returns the errors on the Brick side.

The returned object has the public member variables long errorCountAckChecksum, long errorCountMessageChecksum, long errorCountFrame and long errorCountOverflow.

public int setBootloaderMode(int mode)

Sets the bootloader mode and returns the status after the requested mode change was instigated.

You can change from bootloader mode to firmware mode and vice versa. A change from bootloader mode to firmware mode will only take place if the entry function, device identifier and CRC are present and correct.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

The following constants are available for this function:

  • BrickletThermalImaging.BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletThermalImaging.BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletThermalImaging.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletThermalImaging.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletThermalImaging.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
  • BrickletThermalImaging.BOOTLOADER_STATUS_OK = 0
  • BrickletThermalImaging.BOOTLOADER_STATUS_INVALID_MODE = 1
  • BrickletThermalImaging.BOOTLOADER_STATUS_NO_CHANGE = 2
  • BrickletThermalImaging.BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
  • BrickletThermalImaging.BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
  • BrickletThermalImaging.BOOTLOADER_STATUS_CRC_MISMATCH = 5
public int getBootloaderMode()

Returns the current bootloader mode, see setBootloaderMode().

The following constants are available for this function:

  • BrickletThermalImaging.BOOTLOADER_MODE_BOOTLOADER = 0
  • BrickletThermalImaging.BOOTLOADER_MODE_FIRMWARE = 1
  • BrickletThermalImaging.BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • BrickletThermalImaging.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • BrickletThermalImaging.BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
public void setWriteFirmwarePointer(long pointer)

Sets the firmware pointer for writeFirmware(). The pointer has to be increased by chunks of size 64. The data is written to flash every 4 chunks (which equals to one page of size 256).

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

public int writeFirmware(int[] data)

Writes 64 Bytes of firmware at the position as written by setWriteFirmwarePointer() before. The firmware is written to flash every 4 chunks.

You can only write firmware in bootloader mode.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

public void setStatusLEDConfig(int config)

Sets the status LED configuration. By default the LED shows communication traffic between Brick and Bricklet, it flickers once for every 10 received data packets.

You can also turn the LED permanently on/off or show a heartbeat.

If the Bricklet is in bootloader mode, the LED is will show heartbeat by default.

The following constants are available for this function:

  • BrickletThermalImaging.STATUS_LED_CONFIG_OFF = 0
  • BrickletThermalImaging.STATUS_LED_CONFIG_ON = 1
  • BrickletThermalImaging.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletThermalImaging.STATUS_LED_CONFIG_SHOW_STATUS = 3
public int getStatusLEDConfig()

Returns the configuration as set by setStatusLEDConfig()

The following constants are available for this function:

  • BrickletThermalImaging.STATUS_LED_CONFIG_OFF = 0
  • BrickletThermalImaging.STATUS_LED_CONFIG_ON = 1
  • BrickletThermalImaging.STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • BrickletThermalImaging.STATUS_LED_CONFIG_SHOW_STATUS = 3
public int getChipTemperature()

Returns the temperature in °C as measured inside the microcontroller. The value returned is not the ambient temperature!

The temperature is only proportional to the real temperature and it has bad accuracy. Practically it is only useful as an indicator for temperature changes.

public void reset()

Calling this function will reset the Bricklet. All configurations will be lost.

After a reset you have to create new device objects, calling functions on the existing ones will result in undefined behavior!

public void writeUID(long uid)

Writes a new UID into flash. If you want to set a new UID you have to decode the Base58 encoded UID string into an integer first.

We recommend that you use Brick Viewer to change the UID.

public long readUID()

Returns the current UID as an integer. Encode as Base58 to get the usual string version.

public BrickletThermalImaging.Identity getIdentity()

Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.

The position can be 'a', 'b', 'c' or 'd'.

The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.

The returned object has the public member variables String uid, String connectedUid, char position, int[] hardwareVersion, int[] firmwareVersion and int deviceIdentifier.

Callback Configuration Functions

public void setImageTransferConfig(int config)

The necessary bandwidth of this Bricklet is too high to use getter/callback or high contrast/temperature image at the same time. You have to configure the one you want to use, the Bricklet will optimize the internal configuration accordingly.

Corresponding functions:

The default is Manual High Contrast Image (0).

The following constants are available for this function:

  • BrickletThermalImaging.IMAGE_TRANSFER_MANUAL_HIGH_CONTRAST_IMAGE = 0
  • BrickletThermalImaging.IMAGE_TRANSFER_MANUAL_TEMPERATURE_IMAGE = 1
  • BrickletThermalImaging.IMAGE_TRANSFER_CALLBACK_HIGH_CONTRAST_IMAGE = 2
  • BrickletThermalImaging.IMAGE_TRANSFER_CALLBACK_TEMPERATURE_IMAGE = 3
public int getImageTransferConfig()

Returns the image transfer config, as set by setImageTransferConfig().

The following constants are available for this function:

  • BrickletThermalImaging.IMAGE_TRANSFER_MANUAL_HIGH_CONTRAST_IMAGE = 0
  • BrickletThermalImaging.IMAGE_TRANSFER_MANUAL_TEMPERATURE_IMAGE = 1
  • BrickletThermalImaging.IMAGE_TRANSFER_CALLBACK_HIGH_CONTRAST_IMAGE = 2
  • BrickletThermalImaging.IMAGE_TRANSFER_CALLBACK_TEMPERATURE_IMAGE = 3

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with "set" function of MATLAB. The parameters consist of the IP Connection object, the callback name and the callback function. For example, it looks like this in MATLAB:

function my_callback(e)
    fprintf('Parameter: %s\n', e.param);
end

set(device, 'ExampleCallback', @(h, e) my_callback(e));

Due to a difference in the Octave Java support the "set" function cannot be used in Octave. The registration is done with "add*Callback" functions of the device object. It looks like this in Octave:

function my_callback(e)
    fprintf("Parameter: %s\n", e.param);
end

device.addExampleCallback(@my_callback);

It is possible to add several callbacks and to remove them with the corresponding "remove*Callback" function.

The parameters of the callback are passed to the callback function as fields of the structure e, which is derived from the java.util.EventObject class. The available callback names with corresponding structure fields are described below.

Note

Using callbacks for recurring events is always preferred compared to using getters. It will use less USB bandwidth and the latency will be a lot better, since there is no round trip time.

public callback BrickletThermalImaging.HighContrastImageCallback
Parameters:image -- int[]

This callback is triggered with every new high contrast image if the transfer image config is configured for high contrast callback (see setImageTransferConfig()).

The data is organized as a 8-bit value 80x60 pixel matrix linearized in a one-dimensional array. The data is arranged line by line from top left to bottom right.

Each 8-bit value represents one gray-scale image pixel that can directly be shown to a user on a display.

In MATLAB the set() function can be used to register a callback function to this callback.

In Octave a callback function can be added to this callback using the addHighContrastImageCallback() function. An added callback function can be removed with the removeHighContrastImageCallback() function.

public callback BrickletThermalImaging.TemperatureImageCallback
Parameters:image -- int[]

This callback is triggered with every new temperature image if the transfer image config is configured for temperature callback (see setImageTransferConfig()).

The data is organized as a 16-bit value 80x60 pixel matrix linearized in a one-dimensional array. The data is arranged line by line from top left to bottom right.

Each 16-bit value represents one temperature measurement in either Kelvin/10 or Kelvin/100 (depending on the resolution set with setResolution()).

In MATLAB the set() function can be used to register a callback function to this callback.

In Octave a callback function can be added to this callback using the addTemperatureImageCallback() function. An added callback function can be removed with the removeTemperatureImageCallback() function.

Constants

public static final int BrickletThermalImaging.DEVICE_IDENTIFIER

This constant is used to identify a Thermal Imaging Bricklet.

The getIdentity() function and the EnumerateCallback callback of the IP Connection have a deviceIdentifier parameter to specify the Brick's or Bricklet's type.

public static final String BrickletThermalImaging.DEVICE_DISPLAY_NAME

This constant represents the human readable name of a Thermal Imaging Bricklet.