framesize problem with Mov to DVD

[Burny]

Hello,

I'm having problems with converting a simple file which I exported from FinalCut pro
(using the DV codec with best quality) with ffmpegX.
The file has the extension .dv, it's PAL, framesize 720 x 576.

I want to convert it to DVD or just get an mpeg2 file and let Toast do the rest.
I used the MPEG2 ffmpeg encoder, the target format box showed 720x576, 25 fps, no crop,
I didn't check letterbox (why should I?).
The file I got plays smooth and the quality looks o.k. except it looks distorted lengthwise (x-axis).
If I play it in VLC-player and set VLC to 16:9 (which it shouldn't be) it looks distorted in the other direction.
Source and target format both show the same framsize (720x576).
Whats wrong ? Could someone help me out please ?

My file is 77 minutes long and has PCM stereo sound 16 bit, 48 Khz

If possible could someone also post a detailed method of how to get the best results
coverting mov/dv to DVD with ffmpegX ? (no matter how long the conversion takes,
I'm interested in the best quality possible with ffmpegX.)
Apples Compressor always crashes on my machine and gave me so many troubles that I decided
to try a different tool for exporting to mpeg2 ...

thank you
all the best

[Burny]

Please Help ...

the files I keep getting out of ffmpegX have a framesize of 720 x 540 and I don't know why.
My source and target format is 720 x 576 and that is still what is writen in the boxes under summary.
I don't know what to do, under Video/Video parameters/Autosize I tried DVD and Unconstrained,
both produce a 720 x 540 framesize so everything is slightly distorted ...

Please, please someone tell me how this could be solved ...
thank you
Burny

[Case]

the files I keep getting out of ffmpegX have a framesize of 720 x 540 and I don't know why.

When the computer displays a 720x576 source in a 4:3 frame, the image will be 720x540 (720*3/4=540). QuickTime even goes as far as ignoring the true 720x576 numbers for MPEG files. But many other apps will still recognize the true resolution.
It comes down to the use of rectangular pixels in MPEG-1 and MPEG-2 (and DV), while your monitor uses square pixels. (See pixel aspect ratio.)

My source and target format is 720 x 576 and that is still what is writen in the boxes under summary.

You should trust those numbers more.

[Burny]

Thank you Case,

sorry for the very late reply.
I know the rectangular and square pixels problem, well at least I know that it exists.
But my output file, no matter which software I use to convert my source material to mpeg
still looks slightly distorted lenghtwise (I get eggheads...).
That can't be the natural solution for the square - rectangular pixel problem ?

What I did was converting different vob files from different DVDs
(home made ones, no commercial material, nothing I had to ripp)
back to dv files using drop2dv.
I imported these files in finalcut pro, made titles in between, etc. and exported, trying different ways ...
Because fcps compressor software always crashes on my mac I used ffmpegX also tried Toast for the conversion.
The final DVD I got out of this doesn't look like the original DVDs I took the material from.
As I said they are always a bit distorted.

Do you know why and how to avoid this ?

Another question would be how to avoid shaking images and fence effects in some of the material, not all of them.
Seems it has to do with the different source materials that I want to bring together, bottom field first or the other way round ? but how would I treat the different source materials to make them fit together,
to get a good looking DVD in the end ?


thank you
all the best
Burny

[Burny]

And, sorry I forgot, it also looks like this (distorted lengthwise) if I play it via a DVD player on a TV ?
Not just on the computer screen ...

thanks
best
Burny

[Case]

Both DV and MPEG-2 DVD have 720x576 for PAL framerates, and both do either 4:3 or 16:9. So, I'm baffled as to how your distortion issue could arise. Going from 4:3 to 4:3 or from 16:9 to 16:9 should never result in eggheads. Maybe screenshots could help diagnose this?

The shaky lines could come from a field order problem. All codecs that handle interlacing, except for DV, normally have upper field first. Transcoding DV to MPEG-2 (or vise versa) should be aware of that. If a source file has the field order wrong, then it may get compensated on transcoding when it shouldn't. I don't think ffmpegX has provisions for that. (Maybe the registered version of MovieConverter does? Or does FCP have a special option for opening assets with setting for field order?)

The display aspect ratio should be the same for computer monitor and tv, so that is as expected.