How to extract MP3 and AAC tracks from Youtube videos losslessly in Mac OS X, Windows

#1 04-16-2006, 04:09 AM

ffmpeg is a freeware command-line utility (Windows, Linux, Mac OS X). You can use it to extract MP3 and AAC tracks from downloaded Youtube videos.

Unlike converters the following tutorial allows to extract MP3 and AAC audio tracks from FLV and MP4 files losslessly, so you don't lose quality.

How to extract MP3 and AAC tracks from Youtube .FLV videos losslessly in Mac OS X, Windows, Linux using freeware ffmpeg

First of all find out what type of audio is used in the video file:

Code:

ffmpeg -i inputfile.flv

In case of an MP3 audio track you will get something like
Code:
```
Stream #0.1: Audio: mp3, 44100 Hz, mono, s16, 128 kb/s
```
Now you know that MP3 audio is used, so use the following command:
Code:
```
ffmpeg -i input.flv -vn -acodec copy output.mp3
```
In case of AAC audio track you will get something like
Code:
```
Stream #0.1: Audio: AAC, 44100 Hz, stereo, s16, 128 kb/s
```
Now you know that AAC audio is used, so use the following command to convert to M4A file (extract AAC track into M4A losslessly):
Code:
```
ffmpeg -i input.flv -vn -acodec copy output.m4a
```
or use the following command to convert to bookmarkable M4B file (extract AAC track into M4B losslessly):
Code:
```
ffmpeg -i input.flv -vn -acodec copy output.m4b
```

#2 04-16-2006, 04:09 AM

How to extract MP3 and AAC tracks from Youtube .MP4 videos losslessly in Mac OS X, Windows, Linux using freeware ffmpeg

First of all find out what type of audio is used in the video file:

Code:

ffmpeg -i inputfile.mp4

In case of an MP3 audio track you will get something like
Code:
```
Stream #0.1: Audio: mp3, 44100 Hz, mono, s16, 128 kb/s
```
Now you know that MP3 audio is used, so use the following command:
Code:
```
ffmpeg -i input.mp4 -vn -acodec copy output.mp3
```
In case of AAC audio track you will get something like
Code:
```
Stream #0.1: Audio: AAC, 44100 Hz, stereo, s16, 128 kb/s
```
Now you know that AAC audio is used, so use the following command to convert to M4A file (extract AAC track into M4A losslessly):
Code:
```
ffmpeg -i input.mp4 -vn -acodec copy output.m4a
```
or use the following command to convert to bookmarkable M4B file (extract AAC track into M4B losslessly):
Code:
```
ffmpeg -i input.mp4 -vn -acodec copy output.m4b
```

#3 04-16-2006, 04:09 AM

Replay Media Catcher (RMC) 4 allows to download Youtube videos for free. And you can also use it for extracting MP3 audio tracks from YouTube FLV files to MP3.

How to convert YouTube FLV (with MP3 audio track) to MP3 without losing quality with Replay Media Catcher (RMC) 4 after downloading YouTube FLV file automatically:

Open Replay Media Catcher.
Start Recording
Select the "Audio Extraction (Extract MP3 to MP3)" conversion preset
Navigate to YouTube and start playing videos.
YouTube .FLV streams will be downloaded/captured automatically. Then MP3 audio tracks will be extracted to .MP3 files automatically.

#4 04-16-2006, 04:09 AM

Replay Media Catcher allows to extract AAC audio tracks from FLV files to M4A and M4B.

How to convert YouTube FLV and MP4 video to M4A without losing quality with Replay Media Catcher (RMC) 4 after downloading YouTube video automatically:

Open Replay Media Catcher.
Start Recording
Select the "Audio Extraction (Extract AAC to M4A)" conversion preset
Navigate to YouTube and start playing videos
YouTube .FLV, .MP4 streams will be downloaded/captured automatically. Then AAC audio tracks will be extracted to M4A files automatically.

How to convert YouTube FLV and MP4 video to M4B without losing quality with Replay Media Catcher (RMC) 4 after downloading YouTube video automatically:

Open Replay Media Catcher.
Start Recording
Select the "Audio Extraction (Extract AAC to M4B)" conversion preset
Navigate to YouTube and start playing videos
YouTube .FLV, .MP4 streams will be downloaded/captured automatically. Then AAC audio tracks will be extracted to M4B files automatically.