Strange File Sizes Handbrake

Discussion in 'Apple TV and Home Theater' started by Rmafive, Feb 17, 2012.

  1. macrumors 6502

    Joined:
    Jul 25, 2008
    Location:
    Richmond, Virginia
    #1
    Hey guys,

    I recently switched the way I convert my blu ray movies from a target size of 12 gb to a constant quality of 17.75. I get some very strange results (for example, with a 35 gb mkv source Handrake returns a 29gb file, while a 19 gb source returns a 6gb file). Is this normal and am I getting the best possible quality by using the constant quality setting vs the target size setting? I have plenty of storage for the movies, so size is not an issue!
     
  2. macrumors 6502

    Joined:
    Jun 14, 2010
    #2
    It's normal to get a large variation in output sizes because different movies compress more or less efficiently. Many would say that 17.75 is unnecessarily high for a Blu-ray CQ and you could bump it a couple of points, get smaller average file sizes and not notice any difference.
     
  3. macrumors regular

    Joined:
    Aug 24, 2009
    #3
    That amount of variance is to be expected with constant quality mode, due to the variable amount of detail in the source video.

    17.75 is really way too high for HD sources though. 22 +/- 1 is recommended, so anything above 20 will likely be a complete waste.

    If size really isn't an issue, why not keep the original videos? Compressing them will always reduce the quality very slightly.
     
  4. thread starter macrumors 6502

    Joined:
    Jul 25, 2008
    Location:
    Richmond, Virginia
    #4
    I am trying to get the settings to where I can convert the movies to a more usable format and get the movies down to a reasonable size with very minimal quality loss. I thought a constant quality of about 18 would do that, but I guess that is too high. Would I notice a drop in quality if I move to around 20?
     
  5. obsidian1200, Feb 20, 2012
    Last edited: Feb 20, 2012

    macrumors 6502

    obsidian1200

    Joined:
    Jun 19, 2010
    Location:
    Albuquerque, NM
    #5
    Depends on the films, tbh. I've noticed that, using the ATV2 preset, a constant quality of around 20 causes some HD sources to exhibit artifacting in the encoded product, while bumping it up to 19.5 removes those artifacts (even 19.75 wasn't high enough). Of course, the artifacts you'll experience will vary on the type of movie (animation, action, etc.), I'd rather just have an overall preset that can handle all the blu-rays and DVDs I throw at it and produce reasonably sized files in return.
     
  6. macrumors regular

    Joined:
    Aug 24, 2009
    #6
    Unless you are looking for artifacts, I doubt you'd notice them at 20.

    Personally, I use 19, which is a little higher than it needs to be (I can't see a difference at anything higher than 19.75 unless I freeze playback and spend 5 minutes+ comparing), but it allows a single preset of DVD and blu-ray sources.
     
  7. macrumors 68000

    Joined:
    Jan 26, 2006
    Location:
    Whitehouse, OH
    #7
    I encode everything (DVDs, HDDVDs, Blurays) with one preset @ RF 20. My settings are a variation on the High Profile preset with some of the x264 tuning options. I also use custom anamorphic to increase horizontal resolution to 1280x720 ("future proofing").

    Can't say I've been disappointed with the quality of any of my encodes. They vary in size from 1-7GB in size, depending on source.
     
  8. thread starter macrumors 6502

    Joined:
    Jul 25, 2008
    Location:
    Richmond, Virginia
    #8
    It sounds like the best constant quality is around 19, so I think I'll bump up my setting to something closer to that. I guess there is not much of a quality difference between 17.75 and 19. At least I hope there isn't!
     
  9. macrumors 6502

    obsidian1200

    Joined:
    Jun 19, 2010
    Location:
    Albuquerque, NM
    #9
    I wouldn't recommend messing with the aspect ratio by forcing all your material to fit the 1280x720 window. Granted media with an aspect ratio of 1.78:1 (mostly TV shows) will fit perfectly in that window without distorting the image, you'll be distorting the image of everything else outside that ratio. If you don't mind that, it's not really a problem, but others will probably notice something is "off" about the video if you invite others to watch a movie or two. Plus, in cases where the material isn't 720 pixels high when you crop the blank space out of it, you're increasing the overall file size of the final encode by forcing it to occupy those extra pixels.

    Again, if you don't mind it, it's a nonissue since what matters at the end of the day is how satisfied you are with the final encode :)

    There shouldn't be, but if there is, you can always try adjusting some of the settings under the advanced tab, such as the reference frames, maximum b-frames, adaptive b-frames, etc. Just hover your cursor over each option for a brief explanation and handbrake's recommendation for "sane" values. For trial and error, in the event you find you want to tweak your settings, don't encode the entire file, but just a section where you notice heavy artifacting.
     
  10. macrumors 68020

    Joined:
    Mar 27, 2003
    #10
    Its worth noting that when using constant quality encoding *most* advanced options (such as bframes) will only affect the file size / bitrate that the same quality can be achieved at. Meaning same quality at a higher file size / bitrate.

    There are a few like subme (subq) that will affect quality even at the same rf value (typically at a reduced encoding speed). but not in a major way.
     
  11. NightStorm, Feb 20, 2012
    Last edited: Feb 20, 2012

    macrumors 68000

    Joined:
    Jan 26, 2006
    Location:
    Whitehouse, OH
    #11
    Using custom anamorphic, I'm not adjusting the aspect ratio of the image, I'm changing the aspect ratio of the pixels (square vs. non-square). The only caveat here is that the player software needs to be able to understand this in order to playback the image correctly.

    I should have also noted that this method does not offer any improvement on the current AppleTV, but does help when viewing encodes on my iMac or potentially future hardware (ex. iPad 3 w/ retina display, AppleTV v3, etc). Also, it is really only useful for content that is wider than 1.78:1.
     
  12. macrumors 68020

    Joined:
    Mar 27, 2003
    #12
    Sidenote: NightStorm ... wtf ya been ? :p
     
  13. macrumors 68000

    Joined:
    Jan 26, 2006
    Location:
    Whitehouse, OH
    #13
    Hey dynaflash, good to hear from you again... real life has been keeping me busy. I've stopped by the HB IRC channel a few times, but it was pretty quiet. I'll stop in again soon to see how things are going and catch up.
     
  14. macrumors 6502a

    Joined:
    Dec 20, 2010
    #14
    I have found the sweet spot, for me anyway, when ripping BR, is 18.
     
  15. macrumors regular

    Joined:
    Aug 24, 2009
    #15
    He's using a custom anamorphic encode, so that more detail can be retained whilst staying within the 1280x720 window. It's the same way most 1.78:1 content is encoded on DVD.

    Rather than encoding at ~1280x544 for 2:35:1 content, he is filling the entire 1280x720 frame and then scaling it to the correct ratio on playback. If you start from a 1920x1080 source, it offers a reasonable increase in quality.
     
  16. macrumors 6502

    obsidian1200

    Joined:
    Jun 19, 2010
    Location:
    Albuquerque, NM
    #16
    Of course, to scale it to the correct ratio, that requires the playback software to be able to scale it. If it's not, then you'll have to watch the movie in the 1280x720 window without adjustments to the aspect ratio. So, if you watch movies through Quicktime, iTunes, or on a PS3 or Xbox, you will be watching a distorted image.

    As I said, if it works for Nightstorm (and others), good for him, but generally I wouldn't recommend that method since it's not universally compatible with devices people on this forum may or may not own.
     
  17. macrumors 68000

    Joined:
    Jan 26, 2006
    Location:
    Whitehouse, OH
    #17
    I have no problem with distorted images with any Apple product (iTunes, QT, AppleTV, iDevices, etc)... but that is a good point, some devices don't play nicely with it.
     
  18. macrumors 6502

    obsidian1200

    Joined:
    Jun 19, 2010
    Location:
    Albuquerque, NM
    #18
    That's odd, I've tried the method you've suggested in the past, and iTunes and Quicktime would always playback the image in the original window (be it 720x480, or 1920x1080), regardless of the aspect ratio. And this was semi-recently, too.
     
  19. macrumors regular

    Joined:
    Aug 24, 2009
    #19
    It's not universal, but most of my DVD rips are anamorphic (it's the default setting on most of the Handbrake presets) and all of my Apple devices (including iTunes etc.) handle it fine.
     

Share This Page