解释1：转载自百度问答
　　R5其实就是DVD区码的第5区
　　R5一般大都是俄罗斯5区版，由于北美大片在俄罗斯发行的语种经常配音为俄罗斯语，因此网络上会出现采用R5的视频＋枪版TS的英语原声音频＝合成版本（所以音效差），当然，也经常有未配音过音效好的R5，遇到合成版本，在发布时会特别注明音效．

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解释2：转载自http://hi.baidu.com/webeta/blog/item/ee12251f8a3114c9a686693d.html
　　前几天在VC下载皇家赌场的时候，突然看见电影资源区有人发的文件名包含 R5 Line 字样，当时没在意。后来在学校的BBS讨论时又有人提出了这一问题。于是baidu一下，在CNXP发现了一个关于该问题的解释（地址：http://bbs.cnxp.com/archiver/?tid-946902.html），可惜是英文的，于是我便翻译了一下，希望对大家有帮助。

　　二，正文
　　最近这六个月，大部分电影工作室都提前在俄罗斯发售零售版DVD。他们这样做是为了阻止私人TC版的广泛传播（私人TC版曾经很流行很常见）。但是最近几乎很少有真正的TC版了。你现在所能见到的大部分TC版实际上是R5零售版。R5零售版由电影工作室（匆匆）放出，基本被用来和私人竞争。（由于发布匆忙，）所以电影的后期处理很少有或根本没有。所以R5与TC版本的主要区别是R5是使用专业设备，专业工作室和专业人员。其画质与DVDScr版本很接近。
　　不同版本的质量
　　R1/2 retail > DVDSCR > R5 Retail > Telecine > Telesync > Cam

　　其中带英语音轨的R5标为R5（过去带英语音轨的R5常被错误的标为TC,DVDSCR或者DVDRip）
　　不带英语音轨，后期加入的标为R5.line（过去被标为TC或DVDSCR）

　　英文原文

　　Note on R5/TC's

　　Over the past 6 months the major movie studios have been releasing retail dvds
　　early in Russia. They do this to stop the widespread use of pirated telecines
　　(which were once very common). Lately however there has been very few real
　　telecines, most of the scene telecines you see are actually R5 retails.
　　R5 retail is rushed out by the studio, they are basically competing with
　　pirates, so there is little to no cleanup of the film after the telecine
　　process. So the main difference between telecines put out by the pirates is
　　that the r5's are done using pro equipment, professional studios and
　　professional people. The quality of R5 retail is very similar to dvdscr's,
　　no time is usually spent cleaning up dvdscrs either.

　　The range of quality we now have is like this.
　　R1/2 retail > DVDSCR > R5 Retail > Telecine > Telesync > Cam.

　　Tag: R5
　　Description: Any R5 retail with english audio will be tagged as this.
　　In the past R5 with english audio has been wrong tagged as,
　　TC , DVDSCR and DVDRip
　　We want to cut this bullshit, and just tag as R5, not as dvdrip,
　　just a new category: R5.

　　Tag: R5.LINE
　　Any R5 retail, which hasn't got english audio will be synced to DIRECT
　　english audio and tagged as R5.LINE. In the past these have been
　　tagged as TC (ex: Crank.TC.XviD-ZN) and DVDSCR