340ec2166a
An MPEG layer I, II, and III audio file encoder. PR: 7735 Submitted by: Joel Sutton <jsutton@webnet.com.au>
39 lines
1.4 KiB
Plaintext
39 lines
1.4 KiB
Plaintext
INTRODUCTION
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============
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mp3encode is a package for encoding MPEG layer I, II and III audio
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files. This is the reference implementation so don't expect
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spectacular performance.
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Driving encode is pretty simple although it may take some practice to
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work out an optimal compression rate. AIFF files are the only type of
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files that seem to work with this version so you may need to install a
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port like "sox" to convert your file types. I use the "nas" port to
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record and edit all of my audio files but so long as you have a valid
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AIFF file it shouldn't matter what you use.
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Although the source code includes a decoder I have decided not to port
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it because we already have a couple of top class mpeg decoders in the
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ports collection.
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HINTS & TIPS
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============
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Physcoacoustic model 2 is the only supported model in layer III
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encoding. A bit-rate of 128Kbps is adequate for most forms of music but
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you may need to turn down the compression to 160Kbps if the music is
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particularly atmospheric.
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Vocal spoken recordings are best encoded using a 32Kbps bit-rate with
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layer II (layer III makes you sound like a Dalek under digital water)
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with a 32kHz sample rate in mono. Using this method I have managed to
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get about 5 minutes of AM Radio quality audio into around 1 MB.
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MISC
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====
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If anyone finds any bugs in this software please let me know and
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include patches to fix them.
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Share and enjoy,
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Joel...
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jsutton@webnet.com.au
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