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  36. <h2 class="hilight">LAME - Variable Bit Rate</h2>
  37. </div>
  38. <p>Suggested usage:</p>
  39. <blockquote class="code">lame -V2 input.wav output.mp3</blockquote>
  40. <p>
  41. In Variable Bitrate (VBR) coding, the user chooses a desired quality level
  42. instead of a bitrate. A correct implementation should be able to maintain the
  43. same quality perception, changing the bitrate to a higher or lower one whenever
  44. the audio file is more or less complex. With MP3, this is not always possible.
  45. </p>
  46. <p>
  47. VBR encoding is the logical way of encoding data. General data compressors (like
  48. .zip and .rar) are VBR, as lossless codecs are as well. Being able to indicate
  49. a quality value, the encoder decides for each frame, which is the most appropiate
  50. bitrate to keep it.
  51. </p>
  52. <p>
  53. The main advantage of using VBR is that the encoder will use the smallest amount
  54. of bytes needed to keep the asked quality. The inconvenience is that the
  55. file size is quite unpredictable, and can change from file to file in more than
  56. 50kbps. (or nearly double the size, with different genres and quasi-mono content)
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