View Full Version : letterbox or squeeze for my dvd?
06-20-2004, 10:55 PM
i want my footage to play as letterboxed on standard 4:3 tvs, and full screen on a 16:9 monitor or tv. should i shoot in letterbox, or squeeze, or do dvd authoring programs let me use either to acheive the end result i want? ???
06-20-2004, 10:59 PM
You'd want squeeze mode for that type of DVD.
06-21-2004, 09:54 AM
I you don't have native 16:9 CCD footage or use an anamorphic adaptor, allways stay in 4:3 letterbox and let your wide TV do the uprez. If you uprez in camera (squeeze mode) or in post (NLE, DVD) whatever the performance of yr remapper is, you have to end-up with 525 pixels in vertical direction starting from about 380 lines which introduces aliasing and/or strong vertical lowpass filtering. Keeping in mind that most flat screen TV's (and many CRT TV's these days )don't keep the 525 line structure so the 525 line anamorphic structure has to be remapped again on yr widescreen TV (mine has 768 pixels vertical) which again reduces yr image quality. Going from 380 straight to the TV map makes a significant difference in vertical resolution and aliasing artifacts.
06-21-2004, 11:50 AM
Andre has a good point, thought I'm not sure if it's really that way... I'd say, never use letterbox when shooting, because you just let your camera mask your frame and that is something you can do in your NLE and STILL have the option to correct the frame by moving it up or down (I'm mainly working as an editor and I use this method quite often).
And there is another thread here talking about using anamoprhic lens or squeeze mode, where someone brought up a good point: squeeze mode is uprezzing the frame BEFORE the wavelet compression, so there is a good chance that the frame might look better.
1. Use strech mode (or the anamorphic lens, which has better resolution even on DVDs)
2. just shoot 4:3 and do the letterbox masking in post
I'd prefer #1.
06-21-2004, 02:08 PM
Correct Janbee, indeed I meant 4:3 and go in letterbox in post.That's what I use too (sorry I am a VX2k user and letterbox as such is not available on this cam like it is on the DVX100). Uprezzing is indeed beeing done before compression...compressed images cannot be manipulated. And yes I know that story about better compression, but what you gain there (also depending on applied DV encoder), is more than lost in the vertical lowpass filtering needed for limiting aliasing components in uprez mode.
F.Y.I . DV is an enhanced form of MJPEG encoding based on "Discrete Cosinus Transformation" (DCT) and doesn't relate to Wavelet transformation techniques.
06-22-2004, 12:06 AM
so, if i shoot in squeeze, how will that appear on a 4:3 tv?
if i shoot letterbox, how will that appear on a 16:9 tv?
06-22-2004, 12:17 AM
If you shoot squeeze mode and author it as a widescreen DVD, then it will appear letterboxed on a 4:3 TV, and fullscreen on a widescreen TV.
If you shoot letterbox and author it as a 4:3 DVD, it will look letterboxed on a 4:3 TV, and probably "windowbox" on a 16:9 TV (meaning, it'll have black bars on all four sides).
06-22-2004, 02:42 AM
Indeed 4:3 letterboxed images will stay 4:3 letterboxed on a wide TV, unless yr cam (or in post) the right ID-1 or WSS data can be added and yr widescreen does interprete these codes (like most do). If not you can allways chose manually for "cinema16:9" mode. If those ID info data ares not present, also anamorphic images will stay 4:3 (hor squeezed) on yr screen and have to be adjusted manually. Today most "wide" transmissions in Europe (letterbox!) contain these data.