[If two versions of this make it to the list, my apologies. I made a
mistake with the from: address of the previous copy, and it appears to
have been not sent out to the mailing list. Of course, having re-sent
this (slightly edited) version, they will now both appear.]
Hello all,
I have tried to help myself, and failed...
tcprobe reports this for my input video:
import frame size: -g 720x480 [720x576] (*)
aspect ratio: 4:3 (*)
However, the data is actually 16:9. When I first tried to author a DVD
with this video, I set the aspect ratio flag in the dvdauthor.xml flag
to 16:9.
When I played the results disc with my DVD player, is displayed nicely
on my CRT television, as the DVD player added the letterboxing bars
above and below the image.
However, on a second DVD player, the image was instead shown without the
bars. The picture filled the screen top-to-bottom, making everything
look distorted. Transcode can help, I thought.
I consulted
the man page
http://www.transcoding.org/cgi-bin/transcode?Aspect_Ratio
http://www.transcoding.org/cgi-bin/transcode?Calculating_Frame_Size_And_Aspect_Ratio
and the recent email thread entitled "Transcode and resize" from this
past February.
This gave me the desired results:
transcode -c :0:00.0-:0:05.0 -i video.m2v --export_prof dvd-ntsc --import_asr 3
--export_asr 2 -o test -Z fast
But my understanding is that the "fast" option does not give ideal
quality output video. But I can't get any of the other -Z options to
work, for example this fails:
transcode -c :0:00.0-:0:05.0 -i video.m2v --export_prof dvd-ntsc --import_asr 3
--export_asr 2 -o test -Z 720x480
with this the only apparent problem:
**ERROR: [mpeg2enc] Vertical size is greater than permitted in specified
Level
Question 1: Do I lose video quality with the fast flag to -Z?
Question 1a: If yes, how can I use the -Z option?
Trying to find a solution, I went to the second page referenced above,
and example 6 looked relevant, so I tried this:
transcode -c :0:00.0-:0:05.0 -i video.m2v --export_prof dvd-ntsc --import_asr 3
--export_asr 2 -o test -Z 720x404 -Y -38,0,-38,0
My thinking was that 720 X ( 9 / 16) = 405, which is close to 404, and
then I needed to add black bars 76 pixels wide to get back to the
720x480 frame size.
Again, I got an error:
**ERROR: [mpeg2enc] Vertical size is greater than permitted in specified
Level
Question 2: What am I doing wrong when I try to *not* use the -Z flag?
Thank you for any suggestions,
-Ben Blout
