Getting info about DVDs

Discussion in 'Apple TV and Home Theater' started by Steven Jackson, May 6, 2007.

  1. Steven Jackson macrumors 6502

    Joined:
    Dec 8, 2006
    Location:
    Lincoln, U.K.
    #1
    Hi,

    I have DVDs from several different regions and one thing they have in common is that the technical specifications on the packaging are often inaccurate.

    I am in the process of ripping for AppleTV, but would like accurate info about my DVDs before I start so that I can decide which to rip and which to leave on DVD. Basically, the lower quality stuff will be ripped while the better stuff will stay on disc.

    So...

    1) How do I tell whether a disc is natively interlaced or progressive? This will help me to know whether to use the deinterlace button in Handbrake.

    2) How do I tell whether a disc is anamorphic or letterboxed?

    3) How do I find the frame rate of the main feature?

    Any help much appreciated.

    Steve.
     
  2. Steven Jackson thread starter macrumors 6502

    Joined:
    Dec 8, 2006
    Location:
    Lincoln, U.K.
    #2
    By the way, I know from a previous post that I can use Apple's DVD Player to easily determine whether or not a disc is presented in anamorphic or letterboxed widescreen... However, as my discs come from multiple regions, this is not practical (I don't want to change the region of my drive...)

    Is there a way to determine this using a bog-standard DVD player?

    Steve
     
  3. eddyg macrumors 6502

    Joined:
    Sep 5, 2003
    Location:
    Christchurch, New Zealand
    #3
    You could use Mac The Ripper, and then use VLC to view the DVD from the HD , that's what I do if not sure about the aspect ratio.

    However in general I always leave anamorphic enabled, then every morning I check what the films look like (I do about 10 every night). If they look wonky I reencode them manually with different settings.

    I think that Handbrake is pretty good at figuring out when to auto-disable it.

    I also look for the trademark interlace lines, if I see those then I put that title in for manual encoding.

    I have a process whereby I use a Unix script every night that scans a directory "Encode" and converts all DVDs in that directory using HandbrakeCLI. It then moves that title to an "Encode Verify" directory.

    I notice that HandbrakeCLI sometimes chooses the wrong main feature or the wrong audio track (which Handbrake doesn't - not sure why the difference).

    BTW. Performance of the latest Handbrake SVN is awesome, now get 60fps on my Ma Pro 2.66. About 30min - 40min per DVD.
     
  4. killmoms macrumors 68040

    killmoms

    Joined:
    Jun 23, 2003
    Location:
    Washington, DC
    #4
    As a general rule, DVDs that are of movies shown in theaters (or television shows shot on film, mostly dramas like Lost or House) are progressive, so they do not need to be deinterlaced.

    If you open it in DVD Player and it has black bars in the viewer window, it's letterboxed. If the window gets wide and the image fills the whole window, it's anamorphic.

    The frame rate of the main feature will be 23.976 for film sources and 29.97 for television material.

    Beware, these are only general rules of thumb. Sometimes there are badly authored discs that have a telecine cadence encoded into the video which requires IVTC, but those are few and far between).
     
  5. ezekielrage_99 macrumors 68040

    ezekielrage_99

    Joined:
    Oct 12, 2005
    #5
    1) NSTC is progressive scan.
    PAL is usually interlaced (depending which PAL standard is used).
    Use the "deinterlace" option for all PAL movies because it will reduce screen ripping.

    2) Most movies now are 16X9 Letterbox, I don't know too many anamorphic DVD out there anymore. Plus ananmorphic looks god awful......

    3) NTSC is 29.97 FPS.
    PAL is usually 24 FPS to 25 FPS depending on the type of PAL format being used. If PAL is Field Rendered the frame rate is 50 FPS for smoother animation, this is more for broadcast not home use.

    Check out here for more information on formats.


    Have fun with Handbrake :cool:
     
  6. killmoms macrumors 68040

    killmoms

    Joined:
    Jun 23, 2003
    Location:
    Washington, DC
    #6
    Wow, there's so much wrong stuff in your post I don't know where to begin.

    No, you are wrong. The NTSC and PAL standards are BOTH interlaced, NTSC at 60 fields per second (59.94 technically), PAL at 50. Now, for film transfers the rules are a little different, and for DVD, the rules are different again.

    On NTSC DVDs, most film encodes are progressive 23.976 frames per second (and introducing the 3:2 cadence to correctly display on a standard def television is done by the player). On PAL DVDs, films are simply SPED UP from 24fps to 25fps progressive, and then have the audio pitch corrected (or don't, I've noticed the difference before).

    You have this completely backwards. MOST movies are encoded 16:9 anamorphic. In fact, most very widescreen movies (Cinemascope 2.35:1 ratio) are actually shot and projected anamorphic. This looks BETTER than 16:9 letterbox and has several advantages.

    First, the human eye perceives a loss in vertical resolution more readily than a loss in horizontal resolution. Thus, encoding anamorphically (with the picture squeezed horizontally) allows for full vertical resolution on a 16:9 frame.

    Second, this allows a 16:9 anamorphic encode to be stretched horizontally to fill the screen of a widescreen television (and if it's shown on a 4:3 television, it can be easily letterboxed by the DVD player). A letterboxed 4:3 encode of a 16:9 frame squeezes the entire thing into a 4:3 box, so it'll look fine on a 4:3 TV but will be windowed in the center of a 16:9 TV and will have significantly less vertical resolution—not good.

    You have the first part mostly right. NTSC is actually 59.94 interlaced fields per second. However, PAL is never anything but 50 fields per second, or 25 frames per second.
     
  7. ezekielrage_99 macrumors 68040

    ezekielrage_99

    Joined:
    Oct 12, 2005
    #7
    I wasn't talking about Field Rendering and Scan Lines I was talking about (FPS - Frames Per Second) and yes I am aware they render even then odd fields or odd then even fields depending on the system.

    Whoops my bad about the Letteboxing thing... I was half a sleep while writing the post. I wasn't talking about the different types of aspect ratios (2.35:1, 2.66:1, 2:55:1 , etc) what I meant to type is that most DVDs out there are produced for pure 16:9 standards, which I do know fall under different ration/name standards (there are plenty, I wont list them but it can be found on Wikipedia).

    Most DVD I have in my collection are letterboxed, which makes things fun when I'm ripping a DVD with Handbrake (stupid black bars).

    Again I wasn't talking about fields I was talking FPS (Frames Per Second) not pure Field Renders or Scan Lines.
     
  8. killmoms macrumors 68040

    killmoms

    Joined:
    Jun 23, 2003
    Location:
    Washington, DC
    #8
    To be fair, they are anamorphic and matted, since DVD only specifies an anamorphic mode for 16:9. Interestingly enough, HD DVD and Blu-ray have native 16:9 frame sizes, but don't use an anamorphic mode for 2.35:1 encoding, they just leave in black-bar hard-mattes. I guess they figure we'll never have TVs that wide.
     
  9. Steven Jackson thread starter macrumors 6502

    Joined:
    Dec 8, 2006
    Location:
    Lincoln, U.K.
  10. Steven Jackson thread starter macrumors 6502

    Joined:
    Dec 8, 2006
    Location:
    Lincoln, U.K.
    #10
    HOW? How do you do this. Most of my DVDs take almost an hour to be ripped by Mac The Ripper and take double the length of the film to encode in Handbrake? How come you are ripping so fast?

    iMac 20" -- 2GB RAM -- 2.33 GHz
    Handbrake -- 2 pass -- 2500kbps -- h.264 -- 48/160

    Steve.
     

Share This Page