LinHES Forums
http://forum.linhes.org/

16:9 vs 4:3 with mythburn
http://forum.linhes.org/viewtopic.php?f=6&t=6862		 Page 1 of 1
Author:  ffrr [ Wed Nov 09, 2005 10:58 pm ]
Post subject:  16:9 vs 4:3 with mythburn
I just burnt my first successful DVD using mythweb and mythburn (under R5A22)

One issue, the video is full screen on my 4:3 tv, but the original show was 16:9. There was a warning in the log file concerning this...

WARN: attempt to update aspect ratio from 4:3 to 16:9; skipping

although the wording in the warning seems backwards?

Just one thought - this isn't because I have the default zoom mode for mythtv playback to 'FILL' is it?

Anyway, how can I make my DVD's in the original 16:9 as recorded from my DVB-T card?
Author:  cesman [ Wed Nov 09, 2005 11:00 pm ]
Post subject: 
Me thinks someone is going to have a nice write up to post on the wiki once he has everything running right (or at least the way he wants ;) )...
Author:  ffrr [ Wed Nov 09, 2005 11:57 pm ]
Post subject: 
cesman wrote:
Me thinks someone is going to have a nice write up to post on the wiki once he has everything running right (or at least the way he wants ;) )...


OK, that's fair enough. Only to happy to give a little back.
Author:  ffrr [ Thu Nov 10, 2005 12:31 am ]
Post subject: 
I've been sneaking peeks at the mythtvburn.sh script, and I think the 4:3 aspect ratio is hard coded in it. Could it be as simple as a quick edit in these two places?

firstly,

Code:
echo "<video format='$videoformat' aspect='4:3' />"  >> $myxml


and

Code:
#Create 60 frames for the menu page
#-a is aspect ratio 2=4:3 3=16:9 4=2.21:1
nice jpeg2yuv -v 0 -n 60 -I p -f $framerate -j \
   ${tempdir}/output${page}.png.jpg | \
   nice mpeg2enc -q 2 -a 2 -v 0 -n p -f 8 \
   -o ${tempdir}/background.m2v
Author:  nigelpearson [ Thu Nov 10, 2005 4:45 am ]
Post subject: 
I think those two aspects are just for the shape of the menu screen, and the chapter buttons on it.

On the disks I burn (with a much older version of the scripts), I have no problems with the playback shape. My DVB-based recordings are 16:9, and they play back correctly on a 16:9 TV (when the DVD player is configured for 16:9 too).

The only annoyance is that 4:3 material (which has black bars left and right in the 16:9 frame) has double black bars (i.e. top and bottom too) when played back on a 4:3 TV. I could fix this, but using the zoom key on the DVD layer is easier.
Author:  ffrr [ Thu Nov 10, 2005 5:57 am ]
Post subject: 
nigelpearson wrote:
I think those two aspects are just for the shape of the menu screen, and the chapter buttons on it.


I am sure you're right. I just altered the script and it didn't fix it.

Quote:
On the disks I burn (with a much older version of the scripts), I have no problems with the playback shape. My DVB-based recordings are 16:9, and they play back correctly on a 16:9 TV (when the DVD player is configured for 16:9 too).



OK, it could well be the version I am using, as I upgraded from the new ones in R5A22 (which didn't even work well enough to produce a CD at all - possibly due to permissions I was told). I upgraded to the current cvs version very recently.

I am doing all this from mythweb, so it's using mythwebburn, but that uses the same mythtvburn.sh I think.

Quote:
The only annoyance is that 4:3 material (which has black bars left and right in the 16:9 frame) has double black bars (i.e. top and bottom too) when played back on a 4:3 TV. I could fix this, but using the zoom key on the DVD layer is easier.


I could live with that too.
Author:  ffrr [ Thu Nov 10, 2005 6:29 am ]
Post subject: 
Well, I'm up my neck in the scripts now, and only partially understanding. However, in the remplex.sh script there's a section with multiple choices for remultiplexing the video. By default it uses Project X, but there some DVB specific alternatives.

Code:
#Added on 24 Feb 2005
#   iso13818ps $src $dst

#You may find this is better with DVB streams although DVD author will moan a lot!
#   replex $src $dst

# 28-Dec-04 Added myth-mplex to handle DVB streams although its very slow!
#           although problems have been encountered with audio-sync on DVB streams
#   mythmplex $src $dst

# Only use replex or multiplex though - not both!
#   multiplex $src $dst

# Remux using projectx
   remux_projectx "$src" "$dst"



Is this the process where the aspect ratio is being changed? Is it worth trying replex? Or one of the others (what does iso13818ps do?)?
Author:  badgers [ Fri Nov 11, 2005 10:55 am ]
Post subject: 
I would like to as a question to this group.
I have 640x480 recordings and I want the dvd to keep that resolution and aspect ratio, since I have a 4:3 TV.

ffrr, if you made you recording 16:9 and it is full screen on your 4:3 tv then I have the opposite problem.
Maybe there is a bigger issue when it comes to mythburn and the dvd it creates.
Author:  cesman [ Fri Nov 11, 2005 1:11 pm ]
Post subject: 
I'm by no means a DVD expert, but that isn't a valid DVD resolution. You'll have to use some software to enlarge or provide borders.
Author:  ffrr [ Fri Nov 11, 2005 4:50 pm ]
Post subject: 
cesman wrote:
I'm by no means a DVD expert, but that isn't a valid DVD resolution. You'll have to use some software to enlarge or provide borders.


I am no expert either, BUT nuvexport (using ffmpeg) can produce a DVD that displays 16:9, and maybe it is letterboxed, but all you do is change one number in a script (the aspect ratio of course).

ffmpeg/DVD.pm (in /usr/local/share/nuvexport/export/ffmpeg)make the following change:
In the section marked:
Code:
# Force to 4:3 aspect ratio

Replace or comment:
$self->{'out_aspect'} = 1.3333;

With:
$self->{'out_aspect'} = 1.7777;



So I am just looking to produce the same thing from mythburn.
Author:  jimhayes [ Sun Feb 05, 2006 12:01 pm ]
Post subject: 
I believe I've had the same issue, and identified the cause, if not a complete solution.

see my post here :
http://mysettopbox.tv/phpBB2/viewtopic.php?t=8294
regards,

jim.
Page 1 of 1 All times are UTC - 6 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/