RFE: ffmpeg: change port version number to reflect current svn revision

[dbevans (David B. Evans)]

On their download page ​http://www.ffmpeg.org/download.html, the ffmpeg developers say

FFmpeg has always been a very experimental and developer-driven
project. It is a key component in many multimedia projects and has 
new features added constantly. New, official "releases" are few and 
far between. In short, if you want to work with FFmpeg, you are 
advised to go along with SVN development rather than relying on 
formal releases. SVN snapshots work really well 99% of the time so 
people are not afraid to use them. 

and

If you are looking for a formal release, stop now, there are none. 
Maybe we will have some in the future, but don't hold your breath. 

The ffmpeg port version is 0.4.9pre1_12. This is the number of the last official release of ffmpeg which corresponds to svn revision 3298, Fri Jul 9 20:08:33 2004 UTC, over 4 years ago.

The current ffmpeg port svn revision is 14381 and ffmpeg itself reports its version as

$ ffmpeg --version
FFmpeg version SVN-r14381, Copyright (c) 2000-2008 Fabrice Bellard, et al.

Based on this information, I propose that we change the ffmpeg port version to 0.4.9-${svn_rev} where ${svn_rev} is the current svn revision used in the port.

I think this would yield a more informative and accurate version number that is consistent with the version the program itself reports but allows for possible future release numbers.

I have attached a patch to make this change but in light of the fact that this change is a relatively significant one, I am asking for concurrence and/or comments from the port maintainer (even though the port is marked openmaintainer) before any such change is made.

[dbevans (David B. Evans)]

Patch for Portfile using proposed versioning scheme

[dbevans (David B. Evans)]

addressed by simon in r43093

[(none)]

Milestone Port Enhancements deleted