module PDFToImage

Constants

VERSION: pdftoimage version

Public Class Methods

exec(cmd, error = nil) click to toggle source

Executes the specified command, returning the output.

@param cmd [String] The command to run @return [String] The output of the command

# File lib/pdftoimage.rb, line 60
def exec(cmd, error = nil)
    output = `#{cmd}`
    if $? != 0
        if error == nil
            raise PDFError, "Error executing command: #{cmd}"
        else
            raise PDFError, error
        end
    end

    return output
end

open(filename, &block) click to toggle source

Opens a PDF document and prepares it for splitting into images.

@param filename [String] The filename of the PDF to open

@return [Array] An array of images

# File lib/pdftoimage.rb, line 35
def open(filename, &block)
    if not File.exists?(filename)
        raise PDFError, "File '#{filename}' not found."
    end

    pages = page_count(filename)

    # Array of images
    images = []

    1.upto(pages) { |n|
        dimensions = page_size(filename, n)
        image = Image.new(filename, random_filename, n, dimensions, pages)
        images << image
    }

    images.each(&block) if block_given?

    return images
end

Private Class Methods

page_count(filename) click to toggle source

# File lib/pdftoimage.rb, line 93
def page_count(filename)
    cmd = "pdfinfo #{filename} | grep Pages"
    output = exec(cmd)
    matches = /^Pages:.*?(\d+)$/.match(output)
    if matches.nil?
        raise PDFError, "Error determining page count."
    end

    return matches[1].to_i
end

page_size(filename, page) click to toggle source

# File lib/pdftoimage.rb, line 75
def page_size(filename, page)
    cmd = "pdfinfo -f #{page} -l #{page} #{filename} | grep Page"
    output = exec(cmd)

    matches = /^Page.*?size:.*?(\d+).*?(\d+)/.match(output)
    if matches.nil?
        raise PDFError, "Unable to determine page size."
    end

    scale = 2.08333333333333333
    dimension = {
        width: (matches[1].to_i * scale).to_i,
        height: (matches[2].to_i * scale).to_i
    }

    dimension
end

random_filename() click to toggle source

Generate a random file name in the system's tmp folder

# File lib/pdftoimage.rb, line 105
def random_filename
    File.join(@@pdf_temp_dir, random_name)
end

random_name(length = 15) click to toggle source

Generate a random name of {#length} characters.

# File lib/pdftoimage.rb, line 110
def random_name(length = 15)
    @@chars ||= ("a".."z").to_a + ("A".."Z").to_a + ("1".."9").to_a
    return 'pdftoimage-' + Array.new(length, '').collect { @@chars[rand(@@chars.size)] }.join
end