Official blink(1) control library
Official Python library for blink(1) USB RGB LED notification devices https://blink1.thingm.com/
About this library
This is a rewrite of the original Python library. It includes the following modifications:
- 100% test coverage on all library components
- Python 3.x compatible
- Automatic installation via Python Package Index.
- Higher level control over the blink(1).
- Single implementation with cython-hidapi (instead of PyUSB), intended to be installed with admin access or virtualenv.
This library lives at https://github.com/todbot/blink1-python
Originally written by @salimfadhley, at https://github.com/salimfadhley/blink1/tree/master/python/pypi. Moved to this repository and rewritten for cython-hidapi by @todbot.
Use the pip utility to fetch the latest release of this package and any additional components required in a single step:
pip3 install blink1
Having checked out the blink1-python library, cd to it and run the setup script:
git clone https://github.com/todbot/blink1-python cd blink1-python python3 setup.py develop python3 ./blink1_demo/demo1.py
You can now use the blink1 package on your system. To uninstall the development version:
python3 setup.py develop --uninstall
While blink1-python is not OS-specific, the cython-hidapi library it uses does have platform-specific requirements.
You will need to install extra packages, like:
sudo apt-get install python-dev libusb-1.0-0-dev libudev-dev
Mac OS X:
You will need Xcode installed with command-line tools.
You will need “Microsoft Visual C++ Compiler for Python 2.7” http://aka.ms/vcpython27
The simplest way to use this library is via a context manager.
import time from blink1.blink1 import blink1 with blink1() as b1: b1.fade_to_color(100, 'navy') time.sleep(10)
When the blink1() block exits the light is automatically switched off. It is also possible to access the exact same set of functions without the context manager:
import time from blink1.blink1 import Blink1 b1 = Blink1() b1.fade_to_rgb(1000, 64, 64, 64) time.sleep(3) b1.fade_to_rgb(1000, 255, 255, 255)
Unlike the context manager, this demo will leave the blink(1) open at the end of execution. To close it, use the b1.close() method.
To list all connected blink(1) devices:
from blink1.blink1 import Blink1 blink1_serials = Blink1.list() print("blink(1) devices found:", ','.join(blink1_serials))
To open a particular blink(1) device by serial number, pass in its serial number as a Unicode string:
from blink1.blink1 import blink1 blink1 = Blink1(serial_number=u'20002345') blink1.fade_to_rgb(1000, 255,0,255) blink1.close()
There are a number of ways to specify colors in this library:
b1.fade_to_color(1000, '#ffffff') # Hexdecimal RGB as a string b1.fade_to_color(1000, 'green') # Named color - any color name understood by css3 b1.fade_to_color(1000, (22,33,44) # RGB as a tuple. Luminance values are 0 <= lum <= 255
Attempting to select a color outside the plausible range will generate an InvalidColor exception.
The context manager supports a ‘’gamma’’ argument which allows you to supply a per-channel gamma correction value.
from blink1.blink1 import blink1 with blink1(gamma=(2, 2, 2)) as b1: b1.fade_to_color(100, 'pink') time.sleep(10)
This example provides a gamma correction of 2 to each of the three colour channels.
Higher values of gamma make the blink(1) appear more colorful but decrease the brightness of colours.
White point correction
The human eye’s perception of color can be influenced by ambient lighting. In some circumstances it may be desirable to apply a small colour correction in order to make colors appear more accurate. For example, if we were operating the blink(1) in a room lit predimenantly by candle-light:
with blink1(white_point='candle', switch_off) as b1: b1.fade_to_color(100, 'white')
Viewed in daylight this would make the Blink(1) appear yellowish, hoever in a candle-lit room this would be perceived as a more natural white. If we did not apply this kind of color correction the Blink(1) would appear blueish.
The following values are acceptable white-points:
- Any triple of (r,g,b). Each 0 <= luminance <= 255
- Any color_temperature expressed as an integer or float in Kelvin
- A color temperature name.
The library supports the following temperature names: