@GPU 暂时没时间，你自己调整调整呗。我贴个新版的

require 'net/http'
require "cairo"

def get_url time, x, y
str = "http://himawari8-dl.nict.go.jp/himawari8/img/D531106/20d/550/#{time}00_#{x}_#{y}.png"
end

def merge time
puts "Start image process"
w = 1
h = 20
partial_width = 550
surface = Cairo::ImageSurface.new(w * partial_width, h * partial_width)
cr = Cairo::Context.new(surface)

arr = []
w.times do |x|
h.times do |y|
name = "himawari_#{x}_#{y}.png"
arr.push name
puts name
png = Cairo::ImageSurface.from_png(name)
cr.set_source(*png)
cr.matrix = Cairo::Matrix.identity
cr.translate(x * partial_width, y * partial_width)
cr.paint()
end
end

cr.target.write_to_png("#{time.split("/").join("_")}.png")
cr.destroy
surface.destroy
arr.each do |file|
# File.delete file
end
end

def run time
merge_name = time.split("/").join("_") + ".png"
unless File.exists? merge_name
ts = []
1.times do |x|
thread = Thread.new do
20.times do |y|
name = "himawari_#{x}_#{y}.png"
unless File.exists? name
url = get_url time, x, y
uri = URI.parse(url)
req = Net::HTTP::Get.new uri.path
res = Net::HTTP.start(uri.host, uri.port, use_ssl: false) do |http|
http.request req
end

file = File.open(name, "w+")
file.write(res.body)
file.close
end
end
end
ts.push thread
end
ts.map(&:join)
sleep 30
end

unless File.exists? merge_name
merge time
end
end

# 24.times do |hour|
# hour = hour.to_s
# if hour.length < 2
# hour = "0" + hour
# end
# 6.times do |minute|
# minute = (minute * 10).to_s
# if minute.length < 2
# minute = "0" + minute
# end
# str = "2015/12/01/" + hour + minute
# puts str
# run str
# end
# end

run "2015/12/01/0000"