Live Entropy

This is live entropy from the Photonic Instrument. Press F5 or click your refresh button to er, refresh. The three lines represent the red, green and blue pixel values (0-255) of a continuous strip across the middle of the webcam’s sensor. There are 500 data points on this graph, containing a true entropy of ~11 bits. That’s ~0.05% of the total entropy available from a single frame. This is based on a conservative entropy assessment of 1 bit/jpg byte along files approximately 20kB in size.

Note 1: This is simply the output of the JPEG algorithm, and is therefore only representative of the entropy generated by the Photonic Instrument’s webcam sensor. It’s really a product of discrete cosine transforms, quantization and Huffman decoding. You can think of these lines as pseudo-random entropy. The true entropy is the source JPG file itself.

Note 2: We endeavour to maintain this entropy source on-line at all times, but that’s not always possible. Sometimes maintenance is required, and it goes off-line when the instrument needs greasing. Most Bank holidays are out too. There will be a big red error box and a “Network error:Resource not found…” message during the off times. Apologies.