jpeg 2yuv / mpeg2enc problem : cannot understand error message.
 

I'm trying to build a DVD menu but I get trapped every time I try it. All menus tutorial give roughly the same code as the following:

jpeg2yuv -n 50 -I p -f 29.97 -j pl1.jpg | mpeg2enc -n n -f 8 -o image.m2v

Then I get:

**ERROR: [mpeg2enc] Sample rate is greater than permitted in specified Level

What goes this mean ? What's a "Level" ? Does this have to do with the number next to -n divided by the one next to -f ?

I also tried what the man page suggested to keep -f to 25, like PAL, in order to let mpeg2enc force the NTSC rate, but this doesn't work.

Any help appreciated.