MPEG-4 - How much compression.

Discussion in 'DivX / XviD' started by gmannel, Nov 3, 2005.

  1. gmannel

    gmannel Member

    Joined:
    Nov 3, 2005
    Messages:
    2
    Likes Received:
    0
    Trophy Points:
    11
    What is the sweet spot for MPEG-4 compression? For example, in the case of having ripped a full length modern movie feature to your HD w/ DVD Decrypter in file mode, and then using say Nero Recode 2(or XviD) to convert to MPEG-4, you are given a choice of final target size anywhere from 1 CD at "video quality" level of 568 Kbps to 867 Kbps for a 1 Gb file to a max of 4 Mbps for say a DVD-5. Playing back on an Oppo DVD player to a standard def 60 inch RPTV, at what "video qulality" point would the difference between the original DVD and the MPEG-4 backup become apparent? If I burn to a single layer DVD-5 then the max quality is no problem but if I want to save many movies to a HD array then it would be advantageous to keep the file size to say 1 or 2 Gb if I don't degrade the image(much). Thanks
     
  2. celtic_d

    celtic_d Regular member

    Joined:
    Jan 23, 2005
    Messages:
    3,352
    Likes Received:
    0
    Trophy Points:
    46
    If you aren't targeting a specific filesize then encode using constant quant mode. The lower the average quant, the higher the quality and the higher the bitrate used. Otherwise 2 pass encoding with the bitrate based on the size of the first pass. Say 60-80% of the first pass (which is Q2 for XviD).
     
  3. gmannel

    gmannel Member

    Joined:
    Nov 3, 2005
    Messages:
    2
    Likes Received:
    0
    Trophy Points:
    11
    Does Nero Recode 2 allow constant quant mode? I guess my question would be more clearly stated as "what is the minimum bitrate I should use for quality playback?"
     

Share This Page