Changes between Version 14 and Version 15 of Encode/AAC

Timestamp:

Aug 27, 2013, 5:57:05 PM (13 years ago)

Author:

llogan

Comment:

-q:a works with -c:a aac

Encode/AAC

@@ -97 +97 @@
 == Native FFmpeg AAC encoder ==
 
-The native FFmpeg AAC encoder is included with ffmpeg and is does not require an external library like the other AAC encoders described here. Note that you will not get as good results as with `libfdk_aac`. The `-cutoff` option may improve quality according to [http://d.hatena.ne.jp/kamedo2/20120729/1343545890 Quality Assessment of FFmpeg AAC]. This encoder does not currently work with `-q:a`/`-qscale:a` (see ticket #[ticket:1346]).
+The native FFmpeg AAC encoder is included with ffmpeg and is does not require an external library like the other AAC encoders described here. Note that you will not get as good results as with `libfdk_aac`. The `-cutoff` option may improve quality according to [http://d.hatena.ne.jp/kamedo2/20120729/1343545890 Quality Assessment of FFmpeg AAC]. This is considered an experimental encoder, so `-strict experimental` or `-strict -2` is required.
 
-==== Example ====
+==== Example using `-q:a` ====
+
+{{{
+ffmpeg -i input.wav -strict experimental -c:a aac -cutoff 15000 -q:a 6 output.m4a
+}}}
+
+Effective range for `-q:a` is probably 0.1-10. If ffmpeg ignores `-q:a` then get a newer build (see ticket #[ticket:1346]).
+
+==== Example using `-b:a` ====
 
 {{{
@@ -111 +119 @@
 !VisualOn AAC encoding library. Requires ffmpeg configuration with `--enable-libvo-aacenc`. This has the advantage of not being non-free, and is included by some distributors, but is a rather poor encoder compared to `libfdk_aac` and even the native FFmpeg AAC encoder according to [http://d.hatena.ne.jp/kamedo2/20120729/1343545890 Quality Assessment of FFmpeg AAC]. This encoder supports up to 2 channels, is CBR only, and does not work with `-q:a`/`-qscale:a`.
 
-==== Example ====
 {{{
 ffmpeg -i input.wav -c:a libvo_aacenc -b:a 128k output.m4a
@@ -150 +157 @@
 === Which encoder should I use? What provides the best quality? ===
 
-For AAC-LC the likely answer is: `libfdk_aac` > `libfaac` > Native FFmpeg AAC ≥ `libvo_aacenc`.
+For AAC-LC the likely answer is: `libfdk_aac` > `libfaac` > Native FFmpeg AAC (`aac`) ≥ `libvo_aacenc`.
 
 === Should I use AAC-LC or AAC-HE? ===