Improve ffmpeg caveats regarding AAC

ffmpeg's internal AAC encoder should be preferred over libvo_aacenc due to its much better quality. The experimental label is there for historic reasons -- there is nothing unstable about it.

Changed "-2" to "experimental" argument, because easier to remember.

Added libfdk-aac as it's preferred over libvo_aacenc for quality reasons.

Added meaningful command line examples.

See https://trac.ffmpeg.org/wiki/Encode/AAC

1 files changed, 7 insertions, 5 deletions

diff --git a/Library/Formula/ffmpeg.rb b/Library/Formula/ffmpeg.rb
index 6d7b351b0..47e504062 100644
--- a/Library/Formula/ffmpeg.rb
+++ b/Library/Formula/ffmpeg.rb
@@ -159,15 +159,17 @@ class Ffmpeg < Formula
 
   def caveats
     if build.without? "faac" then <<-EOS.undent
-      FFmpeg has been built without libfaac for licensing reasons.
+      FFmpeg has been built without libfaac for licensing reasons;
+      libvo-aacenc is used by default.
       To install with libfaac, you can:
         brew reinstall ffmpeg --with-faac
 
-      You can also use the libvo-aacenc or experimental FFmpeg encoder to
-      encode AAC audio:
-        -c:a libvo_aacenc
+      You can also use the experimental FFmpeg encoder, libfdk-aac, or
+      libvo_aacenc to encode AAC audio:
+        ffmpeg -i input.wav -c:a aac -strict experimental output.m4a
       Or:
-        -c:a aac -strict -2
+        brew reinstall ffmpeg --with-fdk-aac
+        ffmpeg -i input.wav -c:a libfdk_aac output.m4a
       EOS
     end
   end