himawari.rb

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 = 20
  h = 20
  partial_width = 550
  surface = Cairo::ImageSurface.new(w * partial_width, h * partial_width)
  cr = Cairo::Context.new(surface)

  arr = []
  need_stop = false
  w.times do |x|
    h.times do |y|
      name = "himawari_#{x}_#{y}.png"
      arr.push name
      puts name
      png = Cairo::ImageSurface.from_png(name) rescue nil
      if png.nil?
        need_stop = true
        File.delete name
        break
      end
      cr.matrix = Cairo::Matrix.new(1,0,0,1, x * partial_width, y * partial_width)
      cr.set_source(*png)
      cr.paint()
      png.destroy
    end
    
    if need_stop
      break
    end
  end
  
  if need_stop
    surface.destroy
    cr.destroy
    start
  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 = []
    need_break = false
    20.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 rescue nil
            
            if res.nil?
              need_break = true
            end
            
            unless need_break
              file = File.open(name, "w+")
              file.write(res.body)
              file.close
            end
          end
        end
      end
      ts.push thread
    end
    ts.map(&:join)
    if need_break
      start
      return
    end
    sleep 5
  end
  
  unless File.exists? merge_name
    merge time
  end
end

def start
  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
end

start

@pepsin 太感谢了! 看起来没问题了. 你下载拼接花了多长时间? 直连的么?

@old-woman 两三个小时吧