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47 lines
2.3 KiB
Plaintext
47 lines
2.3 KiB
Plaintext
SoX Resampler Library Copyright (c) 2007-12 robs@users.sourceforge.net
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The SoX Resampler library performs one-dimensional sample-rate conversion.
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It may be used, for example, to resample PCM-encoded audio. For higher-
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dimensional resampling, such as for visual-image processing, you should look
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elsewhere.
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Its aim is to provide fast, high-quality resampling. At its highest quality
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settings, it can produce 32-bit-perfect results with signal occupied-
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bandwidths of up to 98%.¹ Resampling ratios can be any (floating point)
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value between +/- 8 octaves.
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Depending on how the resampler is configured, quality may be traded for
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speed, but only to a certain extent: there may be faster, average-quality
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resamplers available. Multi-channel resampling can be configured to use
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multiple CPU-cores, thus reducing execution time (with a slight expense of
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CPU-cycles).
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The resampler is currently available either as part of `libsox' (the audio
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file-format and effect library), or stand-alone as `libsoxr' (this package).
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The APIs of libsox and libsoxr are slightly different, with that of libsoxr
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designed specifically for resampling. An application requiring support for
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other effects, or for reading-from or writing-to audio files or devices, can
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use libsox (or other libraries such as libsndfile or libavformat).
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Applications may use either floating-point or integer sample formats, and,
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in the case of multiple channels, either channel-interleaved, or split-
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channels.
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The libsoxr API is currently documented in the header file `soxr.h' and by
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example code in the 'examples' directory.
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For compatibility with the popular `libsamplerate' library, the header file
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`soxr-lsr.h' is provided and may be used as an alternative API. For details
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of that API, see http://www.mega-nerd.com/SRC/api.html. Note however, that
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libsoxr does not provide a full emulation of libsamplerate; in particular,
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`vari-speeding' is not currently supported.
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For build and installation instructions, see the file `INSTALL'; for
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copyright and licensing information, see the file `copyright'.
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The resampler was inspired by Laurent De Soras' paper `The Quest For The
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Perfect Resampler', http://ldesoras.free.fr/doc/articles/resampler-en.pdf.
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¹ Note that no practical resampler can be bit-perfect to 100% bandwidth.
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