[FFmpeg-user] trying to work out ffmpeg and avi conversion

[mroper]

hi,


hoping someone can help, i'm fairly new to ffmpeg, trying to work out how to convert an HD 1280x720 
AVI file to mpeg2 so my tv via linux media tomb can play it.


When i try doing....


ffmpeg -i "$filename" -target pal-dvd -b 25000k /destpath/$filename


i get .....Error while opening encoder for output stream #0.0- maybe incorrect parameters such as 
bit_rate, rate, width or height


i've tried searching on the error and drawn a blank, lots of information but nothing I can relate to 
it.  likewise the man pages don't give me a clue.  reason why I have the -b 25000k is I'm trying to 
maintain the quality of the orginal avi, if I don't set this it works fine.  likewise if I set a 
lower rate it also works fine (but at lower quality).  The orginal avi when doing a ffmpeg -i 
filename shows up

     Stream #0.0: Video: mjpeg, yuvj422p, 1280x720, 30 tbr, 30 tbn, 30 tbc
     Metadata:
       strn            : FUJIFILM AVI STREAM 0100
     Stream #0.1: Audio: pcm_s16le, 44100 Hz, 2 channels, s16, 1411 kb/s

Where as the best I can get is via

ffmpeg -i "$filename" -target pal-dvd -s hd720 /destpath/$filename

and produces

   Duration: 00:00:02.00, start: 0.500000, bitrate: 7176 kb/s
     Stream #0.0[0x1e0]: Video: mpeg2video, yuv420p, 1280x720 [PAR 1:1 DAR 16:9], 9000 kb/s, 25 fps, 
25 tbr, 90k tbn, 50 tbc
     Stream #0.1[0x80]: Audio: ac3, 48000 Hz, stereo, s16, 448 kb/s

Which has a much lower quality/bitrate (you can see the difference on screen).

Any ideas?

Thanks

Miles