[MEncoder-users] Generating a 1-second MPEG file from ONE png picture

[scostas]

Hi all:

(the question is nearly at the end. Please, be patient).

To create the menus for a DVD I need an MPEG file made from a PNG 
picture. After trying a lot of things (with big problems with sound 
durations smaller than 17/25 of second) I found this method to create it 
from just one png picture instead of repeating the same picture X times 
with correlative names:

mencoder -srate 48000 ... (options for coding DVD-compliant MPEG2 
files)... -audiofile one_second_of_silence.wav -mf type=png:fps=1 -ofps 
25 mf://my_png_picture.png

I'm setting the FPS for the png to 1 FPS, and the output fps to 25 (or 
30000/1001 for NTSC). Of course I use harddup... This seems to work 
really fine.

The question is: is this 100% legal with Mencoder? This is: it currently 
works, but can it stop working in a near future?

I ask this because when I tried to generate MPEG files using audio files 
of less than 17/25 of second (this is, a PAL file with less than 17 
frames) it failed. And when playing the file with Xine or VLC it ends 
just a little before the end of the file itself (is like it lacks one 
frame). Finally, even using harddup there aren't the classic messages of 
"Duplicate frame", common when the input fps are different than the 
output fps.

Thanks.