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| 3 | <HEAD>
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| 4 | <TITLE>Encoding modes</TITLE>
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| 5 | <META NAME="description" CONTENT="Command line switch reference">
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| 15 | <H1>CBR/ABR/VBR: the 3 encoding modes</H1>
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| 16 | <p> </p>
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| 17 | <p>LAME is able to encode your music using one of its 3 encoding modes: constant
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| 18 | bitrate (CBR), average bitrate (ABR) and variable bitrate (VBR).<br>
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| 19 | <br>
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| 20 | <br>
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| 21 | </p>
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| 22 | <h2>Constant Bitrate (CBR)</h2>
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| 23 | <p>This is the default encoding mode, and also the most basic. In this mode, the
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| 24 | bitrate will be the same for the whole file. It means that each part of your
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| 25 | mp3 file will be using the same number of bits. The musical passage beeing a
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| 26 | difficult one to encode or an easy one, the encoder will use the same bitrate,
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| 27 | so the quality of your mp3 is variable. Complex parts will be of a lower quality
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| 28 | than the easiest ones. The main advantage is that the final files size won't
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| 29 | change and can be accurately predicted.<br>
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| 30 | <br>
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| 31 | </p>
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| 32 | <h2>Average Bitrate (ABR)</h2>
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| 33 | <p>In this mode, you choose a target bitrate and the encoder will try to constantly
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| 34 | maintain an average bitrate while using higher bitrates for the parts of your
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| 35 | music that need more bits. The result will be of higher quality than CBR encoding
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| 36 | while the average file size will remain predictible, so this mode is highly
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| 37 | recommended over CBR.<br>
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| 38 | <br>
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| 39 | </p>
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| 40 | <h2>Variable bitrate (VBR)</h2>
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| 41 | <p>In this mode, you choose the desired quality on a scale going from 9 (lowest
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| 42 | quality/highest distortion) to 0 (highest quality/lowest distortion). Then encoder
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| 43 | tries to maintain the given quality in the whole file by choosing the optimal
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| 44 | number of bits to spend for each part of your music. The main advantage is that
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| 45 | you are able to specify the quality level that you want to reach, but the inconvenient
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| 46 | is that the final file size is totally unpredictible.</p>
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