Adds new photometer class for X-Rite i1Pro colorimeter

hrl/hrl.py

@@ -209,6 +209,10 @@ def __init__(
         elif photometer == "minolta":
             from .photometer.minolta import Minolta
             self.photometer = Minolta("/dev/ttyUSB0")
+
+        elif photometer == "i1pro":
+            from .photometer.i1pro import i1Pro
+            self.photometer = i1Pro("/dev/ttyUSB0")
 
         else:
             self.photometer = None

hrl/photometer/i1pro.py

@@ -0,0 +1,84 @@
+""" Class to read luminance values with X-Rite i1Pro.
+
+It relies on the pypixxlib library from VPixx 
+
+"""
+
+from .photometer import Photometer
+from pypixxlib.i1 import I1Pro
+import pygame
+import numpy as np
+
+def wait_any_button(timeout=0):
+    t0 = pygame.time.get_ticks()
+    btn = None
+    while (timeout == 0) or (pygame.time.get_ticks() - t0 < timeout):
+        event = pygame.event.wait(1)  # waits for only 1 ms
+        if event.type == pygame.KEYDOWN:
+            break
+
+
+class i1Pro(Photometer):
+    def __init__(self, timeout=5):
+        super(i1Pro, self).__init__()
+        self.phtm = I1Pro()
+
+        print("i1Pro device connected")
+        print(f"revision: {self.phtm.revision} - serial number: {self.phtm.serial_number}")
+        self.phtm.setColorSpace("CIEXYZ")
+
+        # check if calibration is necessary
+        self.calibrate()
+
+
+    def calibrate(self):
+        print('****************************************************')
+        print("Calibrating device, put the device on its nest and push the side button")
+        self.phtm.calibrate("Emission")
+
+        print(f"Current color space is {self.phtm.getColorSpace()}")
+        print(f"Current measurement mode is {self.phtm.getMeasurementMode()}")
+        print(f"Current illumination mode is {self.phtm.getIlluminationMode()}")
+        print("... Calibration done.")
+        print('****************************************************')
+        print('')
+        print('Put the device on the screen to be measured and press any key to start / continue the measurements')
+        wait_any_button(timeout=0)
+
+
+    def readTristimulus(self, n=3, slp=1, verbose=False):
+
+        # check if calibration is needed
+        if self.phtm.isCalibrationExpired():
+            self.calibrate()
+
+        # do measurements
+        for i in range(n):
+            try:
+                pygame.time.delay(slp)
+
+                # measure the XYZ tristimulus values
+                self.phtm.runMeasurement()
+                X, Y, Z = self.phtm.getLatestTriStimulusMeasurements()
+                if verbose:
+                    print('Tristimulus values:')
+                    print(f"X: {X}, Y: {Y}, Z:{Z}")
+
+
+                return X, Y, Z
+            except:
+                print("Error in reading from instrument")
+        # if no try was successful
+        return np.nan
+
+
+    def readLuminance(self, n=3, slp=1, verbose=False):
+
+        # reads tristimulus values X, Y, Z.
+        _, lum, _ = self.readTristimulus(n=n, slp=slp, verbose=verbose)
+
+        # returns Y, which is luminance by definition.    
+        return lum       
+
+
+

tests/test_i1pro.py

@@ -0,0 +1,16 @@
+import pytest
+
+pytestmark = [pytest.mark.photometer]
+
+
+def test_initialization(photometer_dev):
+    from hrl.photometer.i1pro import i1Pro
+
+    i1Pro()
+
+
+def test_read_luminance(photometer_dev):
+    from hrl.photometer.i1pro import i1Pro
+
+    device = i1Pro()
+    device.readLuminance(n=1, slp=5)