Trying to Understand Zoom Diffences

Discussion in 'CloneDVD mobile' started by jpierre, Sep 12, 2007.

  1. jpierre

    jpierre New Member

    Can someone please explain the difference in letterbox zoom and cinemascope zoom to me? I've tried looking for an explaination online with no help. All DVD Mobile mannuals avoid this item.
     
  2. mike20021969

    mike20021969 Well-Known Member

    try popping a widescreen film into your drive then starting clonedvdmobile.then try what i''ve suggested below to give you more of an idea what is happening when you 'zoom'.
    letterbox zoom has 3 settings (none,half and full).as you zoom in the left and right of the picture is cropped a little as more of the video starts to fill the 4:3 preview in clonedvdmobile.this is so that when you are watching on an 4:3 lcd screen like on an ipod the video fills more of the screen,and the top and bottom has less letterbox (black areas on the top and bottom of the video).
    the cinemascope zoom (when the box is checked) crops off some if not all of the letterbox and used in conjunction with letterbox zoom>full, should give you (or nearly give you) a full screen video on 4:3 lcd screen.
    how much letterbox remains at the end of all this depends on the aspect ratio of the dvd.
     
    Last edited: Sep 12, 2007
  3. Peer

    Peer Redfox Development Team Staff Member

    Not really complicated. You can right-click on the cinemascope-zoom box to get help.

    You have to know, what (typical) kinds of formats exist.
    1. 4:3 video
      pretty clear
    2. 16:9
      "normal" widescreen
    3. cinemascope, 2.35:1
      "wide-wide"-screen, a format that you often see in the cinemas (a wide-stretched picture through a special lens over 35mm film).
    A DVD "knows" the 4:3 and the 16:9 (anamorphic) formats.
    Cinemascope is encoded as 16:9 with additional black borders on the top and bottom of the pictures:

    [​IMG]

    If you select the "cinemascope zoom", the image will be zoomed just enough to make these black borders disappear, while a part of the picture gets removed on the right and left side (note that CloneDVD mobile can't know, if the picture is really cinemascope, so if the movie doesn't have the black borders, it will be zoomed anyway):

    [​IMG]

    The result is in a way a "real 16:9" format.
    Now you can also use the letterbox zoom. That one serves a different purpose: it will zoom the video to fit your screen dimensions.

    Sometimes, depending on the actual screen ratio of your device, this will remove an unacceptable amount of video material (that's why also a half zoom is being offered as a compromise):

    [​IMG]
     
  4. justthedude

    justthedude Active Member

    The above information should be in the manual. I know, I found it here. But I searched the manual first.

    I have a movie that's listed in the Information block as video format MPEG2 NTSC 4:3 720x480
    But 720x480 is 1.5 or 3:2. So what does this number mean?

    When I get to the "Output Method" I get

    320 x 240 1.33 (This ratio is 4/3)
    480 x 360 1.33
    640 x 480 1.33
    720 x 540 1.33
    720 x 480 1.50 (NTSC TV)
    Without any Letterbox Zoom or Cinamascope option.

    When I try another movie that is listed as MPEG2 NTSC 16:9 720x480.
    I get this output method
    320 x 180 1.78 (same as 16/9)
    480 x 272 1.76
    640 x 360 1.78
    720 x 404 1.78
    852 x 480 1.78
    720 x 480 1.50 (NTSC TV)
    I do get the Letterbox/Cinamascope option.

    Question: Why are they both listed as 720x480 in the information?
    Question: Why do I only get the Letterbox/Cinamascope for 16:9 and not 4:3?

    Thanks.
     
    Last edited: Oct 26, 2007
  5. justthedude

    justthedude Active Member

    I received this answer from the email support.
    -----------------------------------------
    NTSC movies never have square pixels. DVDs come either in 4:4 or 16:9. In both
    cases the resolution is 720x480, just "squeezed" to fit. Black areas don't
    need to be included in the encoding at all. Those areas may be added by the
    playback device if it does not support the correct format. The original format
    will be only displayed correctly on devices that can handle genuine NTSC
    videos.

    Cinemascope movies are encoded in 16:9. They are encoded with the black areas.
    That's why the option to remove them is only available for Cinemascope.

    The other zoom of CloneDVD mobile has another purpose. It is thought to adjust
    the video to the real screen size of the mobile device.