Changes between Version 50 and Version 51 of Encode/AAC

Timestamp:

Oct 4, 2016, 7:27:21 PM (2 years ago)

Author:

llogan

Comment:

moved libfaac into deprecated/removed section

Encode/AAC

@@ -3 +3 @@
 [[http://en.wikipedia.org/wiki/Advanced_Audio_Coding|Advanced Audio Coding (AAC)]] is the successor format to MP3, and is defined in MPEG-4 part 3 (ISO/IEC 14496-3). It is often used within an MP4 container format; for music the .m4a extension is customarily used. The second-most common use is within MKV (Matroska) files because it has better support for embedded text-based soft subtitles than MP4. The examples in this guide will use the extensions MP4 and M4A.
 
-FFmpeg can support three AAC-LC encoders (`aac`, `libfaac`, `libfdk_aac`) and one HE-AAC(v1/2) encoder (`libfdk_aac`). The licenses of `libfaac` and `libfdk_aac` are not compatible with the GPL, so the GPL does not permit distribution of binaries containing code licensed under these licenses when GPL-licensed code is also included. Therefore these encoders have been designated as "non-free", and you cannot download a pre-built ffmpeg that supports them. This can be resolved by [[CompilationGuide|compiling ffmpeg]] yourself.
+FFmpeg can support two AAC-LC encoders (`aac` & `libfdk_aac`) and one HE-AAC(v1/2) encoder (`libfdk_aac`). The license of `libfdk_aac` is not compatible with the GPL, so the GPL does not permit distribution of binaries containing incompatible code when GPL-licensed code is also included. Therefore this encoder have been designated as "non-free", and you cannot download a pre-built ffmpeg that supports it. This can be resolved by [[CompilationGuide|compiling ffmpeg]] yourself.
 
 See also [[Encode/HighQualityAudio]] for general guidelines on FFmpeg audio encoding (which also includes a comparison of which AAC encoder is best quality).
@@ -11 +11 @@
 = libfdk_aac =#fdk_aac
 
-The Fraunhofer FDK AAC codec library. This is currently the highest-quality AAC encoder available with ffmpeg. Requires ffmpeg to be configured with `--enable-libfdk-aac` (and additionally `--enable-nonfree` if you're also using `--enable-gpl`). But beware, it defaults to a low-pass filter of around 14kHz ([[http://wiki.hydrogenaud.io/index.php?title=Fraunhofer_FDK_AAC#Bandwidth|details]]). If you want to preserve higher frequencies, use `-cutoff 18000`.  Adjust the number to the upper frequency limit you prefer, keeping in mind that a higher limit may audibly reduce the overall quality.
+The Fraunhofer FDK AAC codec library. This is currently the highest-quality AAC encoder available with ffmpeg. Requires ffmpeg to be configured with `--enable-libfdk-aac` (and additionally `--enable-nonfree` if you're also using `--enable-gpl`). But beware, it defaults to a low-pass filter of around 14kHz ([[http://wiki.hydrogenaud.io/index.php?title=Fraunhofer_FDK_AAC#Bandwidth|details]]). If you want to preserve higher frequencies, use `-cutoff 18000`.  Adjust the number to the upper frequency limit only if you need to; keeping in mind that a higher limit may audibly reduce the overall quality.
 
 Detailed information about the FDK AAC library (not FFmpeg specific) can be found at [http://wiki.hydrogenaud.io/index.php?title=Fraunhofer_FDK_AAC HydrogenAudio Knowledgebase: Fraunhofer FDK AAC].
@@ -133 +133 @@
 ----
 
+= Deprecated/removed encoders =
+
 = libfaac =
 
-Freeware Advanced Audio Coder. Requires ffmpeg configuration with `--enable-libfaac --enable-nonfree`. Note that you will not get as good results as with `libfdk_aac`.
-
-== Variable Bit Rate (VBR) Example ==
-{{{
-ffmpeg -i input.wav -c:a libfaac -q:a 100 output.m4a
-}}}
-
-Range for `-q:a` is 10-500 and is similar to using the `-q` option in standalone `faac`. 100 is a good value to try.
-
-== Average Bit Rate (ABR) Example ==
-{{{
-ffmpeg -i input.wav -c:a libfaac -b:a 192k output.m4a
-}}}
-
-`libfaac` does not support a true Constant Bit Rate (CBR) mode.
-
-----
-
-= Deprecated/removed encoders =
+Freeware Advanced Audio Coder. [http://git.videolan.org/?p=ffmpeg.git;a=commit;h=dc0f711459e0c682bf9f94ba38d26736e90cff45 Support for this library has been removed].
 
 == libvo_aacenc ==
 
 !VisualOn AAC encoding library. [http://git.videolan.org/?p=ffmpeg.git;a=commit;h=e07e88cd82f78644ddcb10d7d3e0dd624fffe274 Support for this library has been removed]. Use the native FFmpeg encoder instead: it provides better quality and supports more than 2 channels.
-
-----
 
 == libaacplus ==
@@ -199 +181 @@
 == Which encoder provides the best quality? ==
 
-For AAC-LC the likely answer is: `libfdk_aac` > Native FFmpeg AAC encoder (`aac`) > `libfaac`.
+For AAC-LC: `libfdk_aac` > Native FFmpeg AAC encoder (`aac`).
 
 For HE-AAC you have one choice: `libfdk_aac`.