[ATrpms-users] Why can't ffmpeg find ac3 decoder?

[Jeffrey J. Kosowsky]

Axel Thimm wrote at about 18:19:53 +0300 on Monday, June 23, 2008:
 > Hi,
 > 
 > On Mon, Jun 23, 2008 at 10:14:48AM -0400, Jeffrey J. Kosowsky wrote:
 > > When I try: ffmpeg -acodec ac3 -i <mpeg input mpeg2 video> out.mpg
 > > 
 > > I get the error message:
 > >   Unknown decoder 'ac3'
 > > 
 > > This happens even though:
 > >   ffmpeg -formats | grep ac3
 > >   		  DE ac3             raw ac3
 > >   		  EA    ac3
 > 
 > I think the latter means that only the encoder is present.
 > 
 > > 
 > > And I have:
 > > 	ffmpeg-0.4.9-26_r12135.fc8
 > > 	liba52_0-0.7.4-7.0.1.fc8
 > > 
 > > I even tried creating a link (in /usr/lib)
 > >   	 ln -s liba52.so.0 liba52.so
 > > 
 > > but still got the error...
 > > 
 > > Why is ffmpeg not able to convert to ac3.
 > -- 
 > Axel.Thimm at ATrpms.net

Never mind -- my mistake -- the problem is with the order of the
options. I wanted to *encode* in ac3 so I needed to put that after the
'-i' option.