quickie tweet plottin’

#!/usr/bin/env python

import json
import codecs
import Image
from ImageOps import invert
from math import sqrt, pi, sin
from sys import argv
import calendar
import time


latrange = [45, 46]
lonrange = [-123.5, -122]

latgrain = 1/500.0/sqrt(2) # heehee
longrain = 1/500.0

width = int(round((lonrange[1]-lonrange[0]) * 1/longrain))
height = int(round((latrange[1]-latrange[0]) * 1/latgrain))

i = Image.new('RGB', (width, height))
pixels = i.load()

colorincrement = 100


def kz1(v):
    v = v * pi
    r = sin(v)
    g = sin(pi * 2.0/3.0 + v)
    b = sin(pi * 4.0/3.0 + v)
    return (int(r*r*255), int(g*g*255), int(b*b*255))


input = codecs.open(argv[1], 'r', 'utf-8')

for line in input.readlines():
    try: tweet = json.loads(line)
    except: continue

    if tweet['geo']:
        #if tweet['geo']['type'] == 'Point':
        when = calendar.timegm(time.strptime(tweet['created_at'], '%a %b %d %H:%M:%S +0000 %Y'))
        #print when

        ago = time.time() - when

        lat, lon = tweet['geo']['coordinates']
        y = int((lat-latrange[0]) * 1/latgrain)
        x = int((lon-lonrange[0]) * 1/longrain)
        y = height-y

        try:
            pixels[x, y] = kz1(ago/(60*60*24) + 0.5)
            #pixels[x, y] += colorincrement
        except:
            print when, x, y
            #pass

i = invert(i)
i.save(argv[2])