Ok so i am confused about aspect ratio

[lilhobo]

If i want to do DV-DVD tansfer what aspect ratio do i need to get dvd compliant mpeg2 ?

[ou8thisSN]

anything you want. most camcorders come set to 4:3 mode. if you want to leave it that way, you can. those same camcorders have a way to encode in 16:9 mode too, which can be set on the camcorder itself. or you can record in 4:3 mode, then manually frame your shots to be 16:9, then crop the 4:3 image into 16:9 letterbox, using the letterbox(64,64) command in an avisynth file.

thats what I do, because this way there is no scaling at all. I'm not adding anything superflouous to the picture, i'm just taking some away to fit my 16:9 tvs....

but its up to you how you want to do it.

[bb]

DV's resolution is the same as for DVD: 720x576 (PAL) or 720x480 (NTSC), respectively. The DAR (= display aspect ratio) is either 4:3 (i.e. for PAL the video gets stretched to 768x576) or 16:9 (i.e. for PAL the video gets stretched to 1024x576).

The PAR (pixel aspect ratio) is not 1:1 either, but to make a long story short: If your target is a DVD, then you have three options:

1. Your DV is 4:3, you encode 4:3 MPEG-2 for DVD
2. Your DV is 4:3 letterboxed (16:9 with black bars), you encode 4:3 MPEG-2 for DVD
3. Your DV is 16:9 anamorphic (real 16:9), you encode 16:9 MPEG-2 for DVD

You may of course cut off from the top and bottom of a 4:3 video (= cropping) to get 16:9 aspect ratio. To make this DVD compliant, you either add black bars again or resize the cropped video to get back 720x576 / 720x480 resolution. The first method is recommended in this case, because the second just "blows up" the picture without gaining extra information, and it eats more bitrate, too.

bb

[ou8thisSN]

hey, BB... what happens when you SHOOT in 16:9 mode on DV camcorders? do you know the actual format of the CCD... i'm assuming its native 4:3... so if you shoot in 16:9, then you're stretching the picture. is this correct? Fyi I have a Sony consumer camcorder

[theReal]

If your camcorder records real 16:9 then you are stretching the picture (anamorphic). You can compensate for that in your NLE program (mark it "anamorphic" or "16:9" depending on the program) and get 4:3 with black bars or you can watch it with full resolution on a 16:9 capable tv (one that can show anamorphic pictures in the right aspect ratio).

Most consumer camcorders only add black bars to your video (=you don't enhance the resolution, the result is normal 4:3 material with black bars)

[bb]

Camcorders use different ways of taking 16:9 video. Some add black bars, some create real 16:9 anamorphic video (without black bars) which shows up as "egg heads" in the camcorder's 4:3 display, and there are more and more 16:9 camcorders available, too - having a 16:9 CCD chip and a 16:9 display. You can find some information about the topic at Adam Wilt's site, although it may be a little outdated in some aspects (to be found through the "Links" sticky).

bb

[ou8thisSN]

i wonder what my Sony has. it doesnt say anything in the specifications section about the CCD aspect ratio. Although in 16:9 mode, i get the egg-head viewfinder image... so i guess it does true 16:9?

[mic]

Could always try the Sony site -- as an extra costing more money, I would think they'd brag about it on camera info pages.

[ou8thisSN]

heh, mine wsa the first generation of Digital8 DV cameras... i doubt any info on that generation exists on there, just for kick i'll look into the manual.

[mic]

heh, mine wsa the first generation of Digital8 DV cameras... i doubt any info on that generation exists on there, just for kick i'll look into the manual.
I don't know -- I've found some pretty old archives at different manufacturer's sites by googling the site rather then the web. That said, if it's Digital8, personally I think it'll just add bars for 16:9, but I could be wrong.

[SeeMoreDigital]

What are the model numbers of your camcorders?

There's bound to be some test reports about them somewhere on the old interweb ;)

[ou8thisSN]

Dcr-trv103ntsc

[SeeMoreDigital]

Dcr-trv103ntscThere's true 16:9 mode for that model. As it was launched in mid/late 2001...

As far as I know, true 16:9 mode was not available on (consumer) camcorders until sometime in 2003... I'll have to check for a more exact date!


Cheers

[mic]

http://esupport.sony.com/perl/model-documents.pl?mdl=DCRTRV103
http://www.amazon.com/exec/obidos/tg/detail/-/B00000JMO3/104-1160646-3950368?v=glance

FWIW, seems higher end camcorder -- specs list what seems fairly standard CCD -- wide mode produces anamorphic video.

Personally suspect may be a different approach to adding black bars to 4:3 frame, cropping top & bottom & recording results into anamorphic frame. Nothing wrong with that (someone picky may point out potential resizing inaccuracies). AFAIK much pro DV 16:9 work is shot with anamorphic lens which does the same thing optically.

[ou8thisSN]

There's true 16:9 mode for that model. As it was launched in mid/late 2001...

As far as I know, true 16:9 mode was not available on (consumer) camcorders until sometime in 2003... I'll have to check for a more exact date!


Cheers


it could not have been launched in 2001, as we bought it in 1999. in fact the tag on my camcorder says it was built in april 1999. so are you saying if i set it to 16:9 mode, its a true 16:9 on this camcorder, and that there is NO resizing or scaling going on? do you have any type of proof?

[mic]

If it helps, going by specs printed in owners manual off sony site at link I posted...

The CCD of your camera appears pretty average, & images recorded in Wide Mode are anamorphic, meaning they are intended to be expanded the same way an anamorphic widescreen DVD works. And the camera uses one lens & CCD for normal 4:3.

About the only way it would work would be to take the 4:3 scene, cut off the top and bottom, then record that data as a full frame to tape. It would roughly be the same thing as cropping & resize in V/Dub with std DV footage. Any extra resolution would come from the playback device adding pixels from thin air.

A higher end camera might natively capture a widescreen image, or it may use a special lens that captures a wide screen aspect and optically squeezes it into a DV spec frame.

As for *True* widescreen... Your camera, or any other will record a scene as wide as it optically allows, like using wide angle, normal, telephoto lens with an SLR camera. Zoom out to get more width, zoom in to get less width. The difference is really whether you record more height or less, so it turns into opinions and common practice to say something is true widescreen or not (in my opinion :p ). Film started as 4:3, but was altered (cropped) to make a difference from TV. But it's become fashionable enough that it's incorporated in HDTV, so guess that's the way things will progress for a while. :D