Is there a secret to image quality vs. file size?

Discussion in 'Apple TV and Home Theater' started by Michael CM1, May 22, 2013.

  1. macrumors 603

    Joined:
    Feb 4, 2008
    #1
    I just ripped a couple of "Chuck" episodes from Season 2 on BD. I tagged them using Meta Z then gave them the HD tag with Subler. I'm transferring them to my external drive and the two files combined are 10.51GB. I checked the "Deadliest Catch" episodes I just bought from iTunes, and they're about 1.75GB for 1080p 44-minute episodes.

    I'm using the AppleTV 3 settings in HandBrake. I also had this problem with Tropic Thunder and Apollo 13 also being about 10GB. Is there a setting I can change that will make these encode somewhere closer to the iTunes size? I don't have petabyte drives hanging around!
     
  2. macrumors 68020

    Joined:
    Mar 27, 2003
    #2
    Try RF 22 instead of the appleTV 3's RF of 20. This will lower the file size quite a bit and as well lower the quality of the video ... *however* realize that the presets rf of 20 is designed to be a compromise over a variety of sources. so for lower quality sources it gives better quality, but imho it is a bit high (low numerically) for a blu ray source. The better the source quality the higher rf you can use and still maintain visual quality. There are a million opinions on this but I might suggest a test of the exact same source with the ATV 3 preset but at rf 22.

    Also, assuming you are using the new 0.9.9 ... you can try adding this to the "Additonal Options" in the video tab:

    Code:
    b-adapt=2:me=umh
    which will probably slow down the encode some but should reduce the file size.
     
  3. macrumors regular

    Joined:
    Aug 2, 2012
    #3
    Anytime you compress anything, it will loose data. Anytime you transcode anything, it will loose data. The trick is figuring out how much AppleTV3 will tolerate. For example, I used Handbrake with the AppleTV3 preset, transcoded a movie, and the picture quality came out OK. Handbrake took a 6.5 gig MKV movie and spit out an almost two gig movie. To me, that seems a little excessive. It showed massive artifacts on my 65in plasma. I took the same movie and ran it through MKV then iVI and the picture quality drastically improved. iVI compressed very little after transcoding. iVI spit out a 5 gig movie and the picture quality was very much improved. Both transcoded and both compressed the MKV file, but iVI had a very excellent picture quality. My AppleTV3 played this huge 5 gig file just fine with proper frame rate. Point I am making is, compression kills picture quality very much. I would just play around with Handbrake and adjust the RF slider till you get around the same size file than the source. Then see how the picture quality is. The only reason I chose to use iVI is the meta-data tagging built-in.
     
  4. macrumors 68020

    Joined:
    Mar 27, 2003
    #4
    Yeah, but as the OP said ... he doesn't have enough room for that many blu ray sized files. Isn't that the point ?
     
  5. thread starter macrumors 603

    Joined:
    Feb 4, 2008
    #5
    Thanks for the tips, guys. I know an mp4 is going to lose *some* quality over a BD. I'm fine with that. I've reserved myself to being fine with the quality of iTunes HD videos because that's what I'm buying now. So basically I'm happy with that quality.

    I'm just not too familiar with all the little settings that will affect quality vs. file size. I obviously want something better than a rip from a DVD, but I'd like to keep a two-hour movie in the ballpark of 5GB, not 10GB. In all the HD movies and TV shows I have bought from iTunes, the only real issues I have noticed are once or twice in pure black spots on the video. But for the most part, I can't tell the difference from 10 feet.

    I'll play around with it and see if I can get better.
     
  6. thread starter macrumors 603

    Joined:
    Feb 4, 2008
    #6
    Thanks for that info. I have to re-encode the first episode of the disc because I forgot that the version I got for free on iTunes is SD. I even ticked the RF to 22.5 to see how that is for quality. Since right now it's at 2:15 for a 44-minute video, I'm going to hold off on the code you put above. I just wish the HandBrake folks didn't put that preset at a point where it makes the hard disk manufacturers extremely happy. 5GB for 45 minutes is nuts!
     
  7. macrumors 601

    Joined:
    May 21, 2009
    #7
    If you look around in torrents "which I don't"

    There are 1080p movies around 2GB on size that look damn good
    How are they doing this ? Which program do they use & what settings
     
  8. macrumors regular

    Joined:
    Nov 20, 2012
    #8
    FWIW -
    I like to do the following to my Blu-Ray's

    Use MakeMKV
    In Handbrake I use AppleTV 2 preset - I know it's only 720p, but I get a very nice rip that measures in at 2 +/- GB.

    The OP is concerned about size - I am too - so this works well for me.

    I can always re-rip to 1080p in the future if I need to.
     
  9. macrumors 601

    HobeSoundDarryl

    Joined:
    Feb 8, 2004
    Location:
    Hobe Sound, FL (20 miles north of Palm Beach)
    #9
    I know the thread is focused on (smaller) file sizes over maximum quality but I'll simply point out that 4TB external drives are well under $200 these days. 4000GB/5GB (per 45 minutes) = 800 episodes of Chuck at "crazy" quality levels, or 36,000 minutes at a quality setting "too high." Hard drives are really cheap. It's not that expensive to have your cake and eat it too. What might be perfectly acceptable now on whatever television hardware you own today may not look so good on the television hardware you buy tomorrow. Encode tons of stuff today at size over quality and you have another big encoding job in the future if you later notice the quality tradeoffs.
     
  10. macrumors 68000

    phrehdd

    Joined:
    Oct 25, 2008
    #10
    Really a very good point you make on how cheap it is to add a drive and avoid the situation of over compressed movies and at times the tremendous amount of time it takes to compress the movies.

    Compressing BD level material to 2 gigs from 10-25 gig originals is in my estimates a huge hit on quality. One might as well use DVD quality instead if they wish to compress and get similar result, less artifacts, less time taken to compress and then some.

    If people are happy with the results of such extreme compression then go for it. If you have a larger screen size, it will be readily apparent that the image is far less than the original.

    Going back to the quoted post - why not get a large external drive and avoid the headaches?
     
  11. thread starter macrumors 603

    Joined:
    Feb 4, 2008
    #11
    I agree with you in theory. But I'm basing this on a 46" Samsung LED TV I bought just over 2 years ago. Plus I can tell some shows, such as Chuck and The Big Bang Theory, didn't exact make the BDs as sharp as you really could. Both are squeezing the same amount of show (6 Chuck episodes, 12 TBBT episodes) per disc. Meanwhile, you go check out the Lost discs and most of them are three or four episodes and look MUCH BETTER.

    I've begun buying my movies from iTunes because I'm honestly getting sick of storing discs everywhere, I'm finding some pretty good sales (all the Die Hard flicks for $40, Star Trek for $1). I know that I'm missing out on the top video quality most of us can get (I'm not counting 4K), but 99 percent of the time I can't tell. I know I'm also missing all the audio formats on BD, but I'm really surprised at Dolby Digital's quality at times.

    I'm also hoping that at some point Apple will adopt h.265/mpeg-5 and we can get those files upgraded either for free or for some small upgrade charge. Maybe the h.265 standard will include DTS-HD on some future Apple TV. But for now, it's really good enough.
     
  12. HobeSoundDarryl, May 27, 2013
    Last edited: May 27, 2013

    macrumors 601

    HobeSoundDarryl

    Joined:
    Feb 8, 2004
    Location:
    Hobe Sound, FL (20 miles north of Palm Beach)
    #12
    Understood. I'm not really trying to make you change your mind... just point out that you can- for relatively cheap. It's not just about picture quality, there's also sound (iTunes seems married to 1992's Dolby Digital at best while BD uses much more modern audio formats).

    And I appreciate the concept of the conveniences of "buying" from iTunes. Of course, the issue there is that you don't own the movie- just a lifetime lease. You can't sell it, give it away, will it to anyone, easily loan it to a friend, etc. If you own the BD and make your copy from there, you actually own the movie or show and you have full control over the quality of both picture & sound.

    There's also the scenario of deciding to just trust the iTunes storage in the cloud (not having a locally-stored version of the movie) and then losing the movie because the Studio pulled it from iTunes for some reason. This happens regularly- look it up.

    Lastly, you make an assumption that Apple will offer an upgrade to H.265 for cheap or free but there's no obligation for them to do so. And certainly their Studio partners- who would actually make this decision- have a long history of wanting to resell the same stuff to us over and over at full price rather than upgrade the quality for cheap or free. I wouldn't bank on the cheap or free upgrade myself.

    If you own the BD, you could make your own h.265 version and again pick your quality & sound levels. If there is an h.266, you could do it again there too. Each iteration would not come at a cheap (or not cheap) upgrade fee.

    Again, I'm not trying to make you go one way or the other- just pointing out that it's pretty cheap to have much more control over what you want (with no dependencies on Apple or the Studios, no being at the mercy of potential future upgrade prices, no being locked into iTunes, etc). Chuck may not be the pinnacle of BD video viewing experience but someone who is archiving Chuck is probably going to archive at least a few great movies too. 4TB external is much cheaper than $200 right now.
     
  13. thread starter macrumors 603

    Joined:
    Feb 4, 2008
    #13
    I can't disagree with anything you said. I hate the lifetime rental stuff about digital purchases. I'm probably stupid for hoping that in the next few years either laws or contracts will change and the stuff will be ours. All it should take is the wrong person losing his dad's music library that totaled thousands of dollars of songs. That guy gets elected to Congress and is pissed.

    Thanks for all the info. It's a trade off either way. I think I just got sick of discs stacking up on every corner of the house.
     
  14. macrumors 68020

    Joined:
    Mar 15, 2012
    #14
    As someone who has transcoded hundreds of discs to "keep", I bet there is only 10-20 that I consider really worth keeping longterm, so that I can re-watch them. Almost all of them are watch once and move on type entertainment. For that reason, I have started renting (not buying) from iTunes. And I have been very very happy with that new approach. For those things I really feel are worth owning, I will buy and either download or buy from a store.
     
  15. macrumors 6502

    Joined:
    Mar 14, 2004
    #15
    I've always wondered how the scene groups get such high quality in such small file sizes. I converted some of my DVDs using Handbrake and then compared them with DVD rips from torrent sites, and the size of my own rips were nearly twice the size of the scene rips at the same apparent visual quality. If I tried to reduce the size by using the RF slider so it matched the file size of the scene group rips, the image quality of my rips were noticeably worse.

    I don't know how they do it. What's their secret?

     
  16. macrumors 6502

    Joined:
    Apr 5, 2012
    #16
    lol@scene groups having good quality. If you want to do your own high quality rips use x264, preset slower/placebo, and crf 18-20. If the file size is too big for you then there is nothing I can recommend. You either care about quality or you don't. Some movies/shows will need to have a higher bitrate to keep a good quality and that's just the way it is.
     

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