40
votes
Accepted
I can't tag my AAC files with meta-data; what can I do instead?
.aac files are just a "raw" audio stream, they do not support MP3-style tag embedding because AAC is meant to be used with a separate "wrapper" container format to carry those tags ...
- 465k
27
votes
How to decode AAC (.m4a) audio files into WAV?
ffmpeg -i inputFilename.m4a OutputFilename.wav
check out further ffmpeg commands to convert directly to a desired format (mp3 / ogg / aac, ..)
- 638
19
votes
Accepted
ffmpeg: How do I re-encode a video to H.264 video and AAC audio?
Add -c:a aac:
ffmpeg -i input.avi -c:v libx264 -preset slow -crf 20 -c:a aac -b:a 160k -vf format=yuv420p -movflags +faststart output.mp4
input.avi is the input file.
-c:v libx264 selects the video ...
- 60.6k
11
votes
Accepted
Recommended settings to convert Opus to AAC
More generally, I would recommend to have a look at the FFmpeg Wiki page on AAC encoding. Here you will find tips on how to achieve the best quality, which involves:
using the libfdk_aac encoder ...
- 230k
11
votes
Accepted
How to determine AAC bit depth
ffprobe reports correct bit depth but only when there is a bit depth to report, otherwise it reports correctly that "bit-depth" is not applicable (N/A).
In FFmpeg's report of the data field "...
- 758
8
votes
Convert mp3 to wav using FFmpeg for VBR
Use ffmpeg to convert the media, first check file specification using ffprobe.
use this command
ffmpeg -i kimberly.wav -acodec pcm_s16le -ar 16000 -ac 1 song.wav
where
-pcm_s16le is codec 16 bit ...
- 81
6
votes
FFmpeg command to convert MP3 to AAC
Easy convert to AAC for Zeranoe Windows Builds
ffmpeg -i input.mp3 -c:a aac -b:a 128k output.m4a
Use "aac" instead of libfaac or libfdk_aac:
https://trac.ffmpeg.org/wiki/Encode/AAC
"FFmpeg can ...
- 161
5
votes
Accepted
convert mp3 audio to aac m4a audio
If you want to convert with the best quality and your ffmpeg have libfdk_aac (Fraunhofer AAC encoder) you can use command:
ffmpeg -i inFile.mp3 -c:a libfdk_aac outFile.m4a
otherwise, you can use the ...
- 106
5
votes
I can't tag my AAC files with meta-data; what can I do instead?
I have an AAC file which
I am unsure if the term "AAC" file is well defined. Better post the results of a media analyzing software such as GSpot or MediaInfo to determine if your file is
a ...
- 3,748
4
votes
Accepted
VBR encoding with ffmpeg native AAC codec
-vbr is a private option for the encoder libfdk_aac, so it's not available for the native FFmpeg AAC encoder.
According to FFmpeg Wiki: AAC
Variable bit rate (using -q:a):
ffmpeg -i input.wav -c:...
- 60.6k
3
votes
Accepted
Fraunhofer FDK AAC in FFmpeg
The FDK-AAC library is determined by FFmpeg to have a license compatible with the LGPL but not the GPL. The most commonly desired add-on to FFmpeg is the GPLed x264 library, so it's rare to find a ...
- 37.1k
3
votes
converting to the same format many times - how much quality will I lose?
Yes each lossy compression will lower the quality. Converting a file multiple times using the same lossy compression will usually lead to worse output each time. You already noticed it yourself from ...
- 9,203
3
votes
ffmpeg FLAC to AAC encoding
FFmpeg supports two AAC-LC encoders:
Native FFmpeg AAC encoder (aac)
Fraunhofer FDK AAC (libfdk_aac)
FFmpeg supports one HE-AAC encoder:
Fraunhofer FDK AAC (libfdk_aac)
libfdk_aac
libfdk_aac is ...
- 60.6k
3
votes
Accepted
ffmpeg flac to aac (libdfdk_aac) missing metadata
.aac is a raw AAC bitstream and holds no metadata. Output to .m4a or maybe even .mp4.
- 37.1k
3
votes
AAC Sample Rate and Bit Rate for High Quality Audio?
AAC efficiency highly depends on the encoder that's used, of which there are many. Bad AAC encoders can be less efficient than MP3. The number of channels you are encoding is also very important, I ...
- 105
3
votes
Convert MKV with DTS sound to MP4 video with AAC or AC3 audio
You may do this:
ffmpeg -i input.mkv -c:v copy -c:a libfaac out.mp4
Or if there is no joy, try fixing the internal bitstream
Conversion to stereo and asc:
ffmpeg -i input.mkv -c:v copy -c:a ...
- 133
3
votes
ffmpeg: How do I re-encode a video to H.264 video and AAC audio?
ffmpeg -i input -c:v libx264 -b:v 2600k -pass 2 -c:a aac -b:a 128k output.mp4
from the official ffmpeg documentation.
- 174
3
votes
Audio is not in sync after re-encoding with ffmpeg of video and changing audio from eac3 to aac
As counterintuitive as it sounds: This is not an error
The point is, that many audio codecs, can not start at PTS zero - and AAC is one of them. There is a "settling phase" at the beginning (I don't ...
- 20.3k
3
votes
Why am I getting this error when converting m4a file? “Unknown encoder 'libfdk_aac'”
The libfdk license is not compatible with the GNU General Public License. It cannot be distributed with GPL licensed ffmpeg.
What you can do:
Compile ffmpeg by yourself and enable support for libfdk, ...
- 60.6k
2
votes
How to determine AAC bit depth
Truth that those formats are not exactly bit size per sample, but you can take an approximation by having in mind two variables: sample rate and bitrate.
If you know that the sample rate means how ...
- 21
2
votes
Recommended settings to convert Opus to AAC
Just my 2 cents as I asked myself the same question:
best quality available is Opus at the time of download. Forcing a different format will cause an irreversible loss (as observed e.g. in Spek)
...
- 445
2
votes
Accepted
converting to the same format many times - how much quality will I lose?
I agree with Seth:
you'll have to decide whenever the degradation in quality is acceptable for you.
However there's one big flaw in your method. Every time you made a test ("I hear no difference")...
- 75.7k
2
votes
Can MP3 contain AAC?
MP3 isn't really a container format, it's only a self-contained audio compression format, very similar to raw .aac files. It has a small header to indicate whether the contents are MP1/MP2/MP3 (MPEG-1 ...
- 465k
2
votes
Accepted
ffmpeg take channels 7+8 and make a stereo
Add the -ac 2 output option
Your input channels are labeled as DL (downmix left) and DR (downmix right). When these are combined they create the downmix channel layout. Refer to ffmpeg -layouts for a ...
- 60.6k
2
votes
FFmpeg AAC audio copy
The MP4 muxer does not allow aac_latm. Either:
Re-encode the audio with -c:a aac
Or use a different container format such as .ts, .m2t, or .mka.
See #3244 Support LATM AAC in MP4 container.
- 60.6k
2
votes
Accepted
Why does FFmpeg default to libvorbis?
Why does FFmpeg default to libvorbis?
I'm assuming you output to Matroska (.mkv). You can see the defaults with:
ffmpeg -h muxer=matroska
Muxer matroska [Matroska]:
Common extensions: mkv.
...
- 60.6k
2
votes
Can I increase audio gain in a Matroksa file without recoding?
One possibility is to strip the aac audio out, use aacgain to adjust the gain values in the file (not actual transcoding) and then re-mux it back in.
On Windows it appears there is a possibility in ...
- 93.8k
1
vote
FFmpeg drops the Album Art
I faced this problem too, the answer is very easy, just pass -c:v copy and that's all. FFMpeg tries to encode any video to h264 format by default, but audio containers not supporting this, so we ...
- 113
1
vote
VBR encoding with ffmpeg native AAC codec
About that ffmpeg aac wiki...
...the vbr-setting for regular aac-lc says:
"*Variable bit rate using -q:a:
ffmpeg -i input.wav -c:a aac -q:a 2 output.m4a
Effective range for -q:a is around 0.1-2. ...
- 11
Only top scored, non community-wiki answers of a minimum length are eligible