rails3中的回形针处理器

Question

我正在尝试使用回形针将mp3上传到S3，但是当我尝试使用自定义处理器创建质量较低的音频文件时，我遇到了问题。

它似乎有效，但不是在128k输出整首歌，而是只用前6秒。 （当我尝试在命令行使用ffmpeg时，它工作正常）并且它为两个“样式”而不仅仅是片段样式，原始处理也是我不想要的。

song.rb

class Song < ActiveRecord::Base
  belongs_to :record

  #after_save :create_metadata

  Paperclip.interpolates :record_id  do |attachment, style|
    attachment.instance.record_id
  end

  has_attached_file :mp3,
    :styles => { 
      :snippet => { :processors => [:audio_prehear] } 
    },
    :storage => 's3',
    :s3_credentials => "#{RAILS_ROOT}/config/s3_credentials.yml"....

我的处理器

module Paperclip
  class AudioPrehear < Processor
    attr_accessor :resolution, :whiny
    def initialize(file, options = {}, attachment = nil)
      super
      @file = file
      @whiny = options[:whiny].nil? ? true : options[:whiny]
      @basename = File.basename(@file.path, File.extname(@file.path))
    end
    def make
      target = File.dirname(@file.path) + "/" + @basename + ".mp3"
      convert File.expand_path(file.path), target
      dst = File.open target
    end
    def convert (infile, outfile)
      cmd = "-y -i #{infile} -ab 128k #{outfile}"
      begin
       success = Paperclip.run('ffmpeg', cmd)
      rescue PaperclipCommandLineError
        raise PaperclipError, "There was an error processing the preview for #{@basename}" if whiny
      end
    end
  end
end

登录

[paperclip] ffmpeg -y -i /var/folders/Ue/UehOEbyxHkS9voyeIiUx3++++TI/-Tmp-/stream20101223-93966-18vy7po-0.mp3 -ab 128k /var/folders/Ue/UehOEbyxHkS9voyeIiUx3++++TI/-Tmp-/stream20101223-93966-18vy7po-0.mp3 2>/dev/null
....

[paperclip] Saving attachments.
[paperclip] saving music/7635/snippet/monkey.mp3
[paperclip] saving music/7635/original/monkey.mp3
....