parse_pdf.rb

# gem install pdf-reader
require 'pdf-reader'

class ParsePdf
  def initialize(filename)
    @reader = PDF::Reader.new(filename)
  end

  def process
    result = []
    @reader.pages.each_with_index do |page, index|
      result << parse_lines(page.text.split("\n")) if (index + 1) % 4 == 0
    end
    result
  end

  def parse_lines(lines)
    lines = lines[20..24].map { |line| line.strip.split(/\s{5,}/) }
    lines.map { |line| line.first if line.length > 1 }.compact
  end
end

# Example:
# parse = ParsePdf.new("feeds.pdf")
# p parse.process