Log in

View Full Version : FAQ on how to use the new 16:9 selection in the video encoder


ScooterMyth
23rd April 2002, 00:13
As explained by Nick:

It all depends on what sort of TV you are going to be watching on.

Let us first take the example of a 4:3 TV with an anamorphic 16:9 DVD.

The DVD picture is 720 pixels wide and 576 deep (PAL). Something on the DVD tells your player it is in 16:9 format and when you set up your DVD player you will have told it in the setup menu that you have a 4:3 TV. Hence what your DVD player does is create a 4:3 output to send to the TV by squashing the image into the middle 432 lines and adds 72 lines of black top and bottom. These lines are not on the disc, they are added by your DVD player to create an output suitable for a 4:3 TV.

However, if you set up your DVD player telling it you have a widescreen TV it outputs the picture 16:9 exactly as it is on the disc.

Now let's move onto the conversion.

When we convert DVD to SVCD we have three options with the new build (Ignore the "Resize to " option in the Frameserver tab, we're talking conversion tab here).

Option 1: 16:9, borders added, encode as 4:3. This is exactly like the 16:9 tab in previous builds. What this does is make a disc which gives a 4:3 output by squashing the picture into the middle third and actually putting black bars on the disc, so the actual movie is contained in the middle 432 lines of the 576 available, the rest is black. When played on a 4:3 TV the result looks the same as when your DVD player added the bars when you played the original DVD. However, on a 16:9 widescreen TV the picture has to be stretched both horizontally and vertically to fill the screen. Pretty much every widescreen TV has picture zoom modes to do this but lots of stretching = poor picture quality.

Option 2: 4:3, no borders added, encode as 4:3. This is exactly like 4:3 in previous builds. This encodes a 4:3 disc with the full 576 line vertical resolution. Because the output from this disc in 4:3 the DVD player does not know to add black lines top and bottom to output to your 4:3 TV so the egghead effect ensues. Some TV's have picture modes to add black bars but the vast majority don't. However, played on a widescreen TV, you only have to stretch horizontally to fill the screen as it is already at full vertical resolution. Less stretching = better picture quality so if you will be watching on a widescreen TV this option is a winner.

Option 3: Anamorphic, no borders added, encoded as 16:9. This is the new option on 1.0.8b1. What this does is encode at full vertical resolution but put a marker on the disc just like the original DVD to tell your player that it is 16:9. Therefore if you set up your DVD player saying you have a widescreen TV, the DVD player outputs at full vertical resolution but if you set it for a 4:3 TV the player does the squashing up and adding of black bars. So you get the best of both worlds - perfect playback on either TV type.

The only problem is that it appears most standalone DVD players are incompatible with this new option and picture distortion results. Either which way, there is no need to resort to uninstalling this build and reinstalling an earlier version. If the 16:9 anamorphic option doesn't work for you simply don't use it! The other two options are exactly as per previous builds.

DDogg
23rd April 2002, 00:20
Nice write up Scooter. Nice to see that your old poot self is still above the ground :)

ScooterMyth
23rd April 2002, 00:24
Thanks. All the credit goes to Nick who replied to a very confusing thread about this issue. I'm still kicking around here. I'm letting the more talented "youngsters" answer the questions, though! :)

Glad to see you haven't forsaken us.

Scooter

RoopeT
23rd April 2002, 08:48
One more thing about encoding 16.9 vs. 4:3 with black borders:

If you're encoding 16:9 the resolution is 480x576 (PAL), but if you're encoding 4:3 with borders you're effectively encoding 480x432, thus requiring less bitrate.

markrb
24th April 2002, 03:59
ScooterMyth and Nick if it's ok with you guys I would like to intergrate this in to the DVD2SVCD Guide and FAQ and kill this sticky.


Mark

Nick
24th April 2002, 17:56
fine by me!

ScooterMyth
25th April 2002, 08:09
Not a problem.