russss

Now moved to my blog

russss

NOTE: this is a work-in-progress draft, please don't implement anything based on this yet. It's also missing a name. Suggestions very much appreciated.

Introduction to UHF RFID

UHF RFID tags (also known as "Gen 2" or "RAIN") are the lesser-known third type of RFID. Operating in the unlicensed 868MHz (EU)/900MHz (US) bands, they have a read range of up to 10m with a relatively low-cost, passive tag.

These tags are used by large retailers, including Decathlon and Uniqlo, for inventory control, barcodeless checkout, and theft prevention. (If you buy anything from Decathlon, make sure you cut the sewn-in tag out or your products will be uniquely trackable.)

UHF RFID tags include a unique identifier which usually either follows the GS1 Electronic Product Code standard or ISO/IEC 15961-1. Unfortunately, for both of these, you have to pay a hefty annual fee to get a prefix. To GS1's credit, all their specifications are freely available.

russss

import proj4 from 'proj4'

proj4.defs([
    [
        'CCCAMP2019',
        '+proj=tmerc +ellps=GRS80 +lat_0=0 +lon_0=15 +k=0.9996 +x_0=114350 +y_0=-5877600 +units=m +no_defs',
    ],
])

type CoordsLike = [number, number] | maplibregl.LngLat

russss

import cv2
import numpy as np

def deskew(im, max_skew=10):
    height, width = im.shape

    # Create a grayscale image and denoise it
    im_gs = cv2.cvtColor(im, cv2.COLOR_BGR2GRAY)
    im_gs = cv2.fastNlMeansDenoising(im_gs, h=3)

russss

# coding=utf-8
from __future__ import division, absolute_import, print_function, unicode_literals
import csv
import boto3
from zipfile import ZipFile
import io
import tempfile
from decimal import Decimal
import datetime
from collections import defaultdict

russss

• Sexist, homophobic, racist, transphobic, ableist, sexist or otherwise offensive remarks are not allowed. (Swearing is allowed, but never targeting another user, and never in a hateful or sexually explicit manner.)
• Remarks that make any of the ops go “Hm, that’s inappropriate”, whether on the above list or not: also not allowed.
• You get a warning.
• If the warning is not taken seriously, you might get a second sterner warning in PM, if you’re lucky, and the op is feeling generous, and this is the first time. But don’t count on that.
• If the warning is unheeded, you get kicked.
• If you come back and continue to make trouble, you get banned.
• If you contact the offended party, and are truly apologetic, and it was the first offense, and the op who banned you feels it’s appropriate, then you may get un-banned.
• If an op bans you, I’m definitely not going to unban you unless they agree it’s a good idea.
• If an op bans someone, and you think it was unjustified, take it up with that op, or with a differe

russss

define command {
    command_name     notify-host-by-irccat
    command_line     /usr/local/share/nagios-plugins/icinga-irccat.py $HOSTNAME$ $HOSTSTATE$ | /bin/nc -q0 irccat-host 12345
}

define command {
    command_name     notify-service-by-irccat
    command_line     /usr/local/share/nagios-plugins/icinga-irccat.py -s "$SERVICEDESC$" -o "$SERVICEOUTPUT$" $HOSTNAME$ $SERVICESTATE$ | /bin/nc -q0 irccat-host 12345
}

russss

### Keybase proof

I hereby claim:

  * I am russss on github.
  * I am russss (https://keybase.io/russss) on keybase.
  * I have a public key whose fingerprint is BE75 264B 665E D97E A5DB  EFD5 F52F C56D D906 FEB1

To claim this, I am signing this object:

russss

set nonumber
syntax on
filetype plugin indent on

augroup myfiletypes
  autocmd!
  autocmd BufNewFile,BufRead *.jinja        set filetype=jinja
  autocmd BufNewFile,BufRead *.sql          set filetype=psql
  autocmd BufNewFile,BufRead *.migration    set filetype=psql
  autocmd BufNewFile,BufRead *.vcl          set filetype=vcl

russss

# Listen to a CurrentCost monitor on the serial port and forward data to Graphite
import serial
import socket
import time
from lxml import etree

ser = serial.Serial('/dev/ttyUSB0', 57600)

def send_metric(value):
    sock = socket.socket()