Ruby - Thermal Imaging Bricklet

This is the description of the Ruby 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 Ruby API bindings is part of their general description.

Examples

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

Callback

Download (example_callback.rb)

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#!/usr/bin/env ruby
# -*- ruby encoding: utf-8 -*-

require 'tinkerforge/ip_connection'
require 'tinkerforge/bricklet_thermal_imaging'

include Tinkerforge

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

ipcon = IPConnection.new # Create IP connection
ti = BrickletThermalImaging.new 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
ti.register_callback(BrickletThermalImaging::CALLBACK_HIGH_CONTRAST_IMAGE) do |image|
    # image is a array of size 80*60 with 8 bit grey value for each element
end

# Enable high contrast image transfer for callback
ti.set_image_transfer_config BrickletThermalImaging::IMAGE_TRANSFER_CALLBACK_HIGH_CONTRAST_IMAGE

puts 'Press key to exit'
$stdin.gets
ipcon.disconnect

API

All methods listed below are thread-safe.

Basic Functions

BrickletThermalImaging::new(uid, ipcon) → thermal_imaging
Parameters:
  • uid -- str
  • ipcon -- IPConnection

Creates an object with the unique device ID uid:

thermal_imaging = BrickletThermalImaging.new 'YOUR_DEVICE_UID', ipcon

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

BrickletThermalImaging#get_high_contrast_image → [int, int, ..4797x.., int]

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 #set_image_transfer_config.

BrickletThermalImaging#get_temperature_image → [int, int, ..4797x.., int]

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:rb:func:#set_resolution <BrickletThermalImaging#set_resolution>).

Before you can use this function you have to enable it with #set_image_transfer_config.

BrickletThermalImaging#get_statistics → [[int, int, int, int], [int, int, int, int], int, int, [bool, bool]]

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 array has the values spotmeter_statistics, temperatures, resolution, ffc_status and temperature_warning.

BrickletThermalImaging#set_resolution(resolution) → nil
Parameters:resolution -- int

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
BrickletThermalImaging#get_resolution → int

Returns the resolution as set by #set_resolution.

The following constants are available for this function:

  • BrickletThermalImaging::RESOLUTION_0_TO_6553_KELVIN = 0
  • BrickletThermalImaging::RESOLUTION_0_TO_655_KELVIN = 1
BrickletThermalImaging#set_spotmeter_config(region_of_interest) → nil
Parameters:region_of_interest -- [int, int, int, int]

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 #get_statistics.

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

BrickletThermalImaging#get_spotmeter_config → [int, int, int, int]

Returns the spotmeter config as set by #set_spotmeter_config.

BrickletThermalImaging#set_high_contrast_config(region_of_interest, dampening_factor, clip_limit, empty_counts) → nil
Parameters:
  • region_of_interest -- [int, int, int, int]
  • dampening_factor -- int
  • clip_limit -- [int, int]
  • empty_counts -- int

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

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.
BrickletThermalImaging#get_high_contrast_config → [[int, int, int, int], int, [int, int], int]

Returns the high contrast config as set by #set_high_contrast_config.

The returned array has the values region_of_interest, dampening_factor, clip_limit and empty_counts.

Advanced Functions

BrickletThermalImaging#get_api_version → [int, int, int]

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.

BrickletThermalImaging#get_response_expected(function_id) → bool
Parameters:function_id -- int

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 #set_response_expected. 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 #set_response_expected for the list of function ID constants available for this function.

BrickletThermalImaging#set_response_expected(function_id, response_expected) → nil
Parameters:
  • function_id -- int
  • response_expected -- bool

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
BrickletThermalImaging#set_response_expected_all(response_expected) → nil
Parameters:response_expected -- bool

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

BrickletThermalImaging#get_spitfp_error_count → [int, int, int, int]

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 array has the values error_count_ack_checksum, error_count_message_checksum, error_count_frame and error_count_overflow.

BrickletThermalImaging#set_bootloader_mode(mode) → int
Parameters:mode -- int

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
BrickletThermalImaging#get_bootloader_mode → int

Returns the current bootloader mode, see #set_bootloader_mode.

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#set_write_firmware_pointer(pointer) → nil
Parameters:pointer -- int

Sets the firmware pointer for #write_firmware. 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.

BrickletThermalImaging#write_firmware(data) → int
Parameters:data -- [int, int, ..61x.., int]

Writes 64 Bytes of firmware at the position as written by #set_write_firmware_pointer 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.

BrickletThermalImaging#set_status_led_config(config) → nil
Parameters:config -- int

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
BrickletThermalImaging#get_status_led_config → int

Returns the configuration as set by #set_status_led_config

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
BrickletThermalImaging#get_chip_temperature → int

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.

BrickletThermalImaging#reset → nil

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!

BrickletThermalImaging#write_uid(uid) → nil
Parameters:uid -- int

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.

BrickletThermalImaging#read_uid → int

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

BrickletThermalImaging#get_identity → [str, str, str, [int, int, int], [int, int, int], int]

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 array has the values uid, connected_uid, position, hardware_version, firmware_version and device_identifier.

Callback Configuration Functions

BrickletThermalImaging#register_callback(callback_id) { |param [, ...]| block } → nil
Parameters:callback_id -- int

Registers the given block with the given callback_id.

The available callback IDs with corresponding function signatures are listed below.

BrickletThermalImaging#set_image_transfer_config(config) → nil
Parameters:config -- int

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
BrickletThermalImaging#get_image_transfer_config → int

Returns the image transfer config, as set by #set_image_transfer_config.

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 the #register_callback function of the device object. The first parameter is the callback ID and the second parameter is a block:

thermal_imaging.register_callback BrickletThermalImaging::CALLBACK_EXAMPLE, do |param|
  puts "#{param}"
end

The available constants with inherent number and type of parameters 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.

BrickletThermalImaging::CALLBACK_HIGH_CONTRAST_IMAGE
Parameters:image -- [int, int, ..4797x.., int]

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

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.

BrickletThermalImaging::CALLBACK_TEMPERATURE_IMAGE
Parameters:image -- [int, int, ..4797x.., int]

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

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 #set_resolution).

Constants

BrickletThermalImaging::DEVICE_IDENTIFIER

This constant is used to identify a Thermal Imaging Bricklet.

The #get_identity() function and the ::CALLBACK_ENUMERATE callback of the IP Connection have a device_identifier parameter to specify the Brick's or Bricklet's type.

BrickletThermalImaging::DEVICE_DISPLAY_NAME

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