annotate wiki/AIMCDataFormat.wiki @ 438:bc75da283e83
Edited wiki page AIMCDataFormat through web user interface.
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tom@acousticscale.org |
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Thu, 04 Nov 2010 18:34:46 +0000 |
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1 #summary AIM-C simple data file format.
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3 The module [http://code.google.com/p/aimc/source/browse/trunk/src/Modules/Output/FileOutputAIMC.cc FileOutputAIMC] provides data in a simple format which can be read by other programs.
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5 The data is stored as 32-bit floats with the native byte-ordering of the machine the file was written on. Before the data, there is a simple header.
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7 == Header format ==
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8 The first 20 bytes of the file contain the following fields:
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9
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10 * 32-bit unsigned integer: frame count - total number of frames in the file (these can be SAIs, filterbank output frames or other things (eg. features), but all frames in the file are of the same type)
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11 * 32-bit float: frame period (the interval between adjacent frames in milliseconds) (TODO(tom): this is currently not set properly).
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12 * 32-bit unsigned integer: channel count (number of frequency channels in the output)
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13 * 32-bit unsigned integer frame length (length of each frame in samples)
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14 * 32-bit float: sample rate (audio sample rate in Hz)
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17 == Reading the files using MATLAB ==
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18 Use [http://code.google.com/p/aimc/source/browse/trunk/matlab/AIMCread.m the MATLAB AIMCread function] to read the files. |