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Topic: what's the difference of AAC, M4A and M4P?

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Old 10-23-2007, 02:27 AM
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Smile what's the difference of AAC, M4A and M4P?

Can anybody help me?

what is the difference of aac, m4a and m4p?

all of them seems to be the music format provided by Apple, but what's the difference? How can I covert them?

Thanks!!
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Old 10-23-2007, 04:36 AM
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M4P is fairplay protected content (iTunes Store), AAC/M4A are essentially the same thing just different extensions.



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Old 10-23-2007, 12:37 PM
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Raw *.aac files are just that, they are raw AAC audio without any container. See, there are many containers out there and these containers can hold certain types of audio and video data. AAC audio is normally wrapped in a mpeg-4 container to make life easier. mpeg-4 AAC audio commonly had three types of filenames: *.m4a (used commonly by iTunes, Apple pretty much set this standard up), *.mp4 (commonly used by other, less known applications), and *.m4p (used only by Apple to show that your content was purchased from the iTunes Store). You can freely go from a *.mp4 to *.m4a by renaming your files, there is no need to convert since they are essentially the same thing.

You cannot simply convert a *.m4p file though as it contains DRM and prevents you from doing so. You will have to burn that to a audio CD and rip it as a different format. *.aac files can be made into *.m4a/*.mp4 files by taking the AAC audio and manually putting it in a mpeg-4 container. This can be done with many different applications. All of those formats are essentially the same thing though but their filenames distinguish them for different uses.



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Old 10-26-2007, 05:34 AM
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kornchild2002, thank you soooo much. I learn something new.

Thank you , lee, I will have a try at the program you recommend, since I don't have a CD burner, NoteBurner may be more suitable.

Thanks
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Old 11-21-2007, 05:45 AM
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1. AAC stands for either MPEG2 Advanced Audio Coding or MPEG4 Advanced Audio Coding.
The MPEG2 audio-encoding standard of the format is not backward-compatible with MPEG1 audio. MPEG2 AAC can produce better audio quality than MP3 using less physical space for the files. MPEG4 AAC can produce better quality and smaller files than MPEG2 AAC. AAC is the audio file format used by Apple in their popular iTunes Music Store

2. The audio file format used by Apple in their popular iTunes Music Store often appears on your system with the ".M4A" filename extension. M4A can produce better audio quality than MP3 using less physical space for the files

3. M4P format is "protected AAC". It is a format of purchased music that can be listened to only through the iTunes softer or an iPod.
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Old 11-21-2007, 11:46 AM
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Careful kevin, not all mp3 encoders are alike and saying that "m4a can produce better audio quality than mp3" is true but the differences between the iTunes/Nero AAC encoders and Lame mp3 encoders are minimal that the average listener would not hear them. Wow, that was a long statement.



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Old 11-21-2007, 09:15 PM
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The LAME MP3 encoder is good. The iTunes MP3 encoder is not.
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Topic: what's the difference of AAC, M4A and M4P?

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