Mercurial > hg > aim92
comparison man/man1/ftgram.1 @ 0:5242703e91d3 tip
Initial checkin for AIM92 aimR8.2 (last updated May 1997).
| author | tomwalters |
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| date | Fri, 20 May 2011 15:19:45 +0100 |
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| -1:000000000000 | 0:5242703e91d3 |
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| 1 .TH FTGRAM 1 "1 September 1993" | |
| 2 | |
| 3 .SH NAME | |
| 4 ftgram \- Autocorrelogram auditory image. | |
| 5 | |
| 6 .SH SYNTAX | |
| 7 ftgram [arguments] [file] | |
| 8 | |
| 9 .SH DESCRIPTION | |
| 10 Short-time Fourier transform applied to each row of input frames. | |
| 11 Output frames consist of row-wise magnitude spectra, computed using fft. | |
| 12 | |
| 13 The program expects to read an AIM header, and interprets input as one large | |
| 14 frame in column-wise format (eg output from genbmm, gennap, etc.), to be | |
| 15 divided into input frames, each to be processed by row-wise fft. | |
| 16 A new header is constructed, and each fft-gram frame is output in | |
| 17 row-wise format (eg as if output from gensai). | |
| 18 | |
| 19 The input is divided into frames according to the given options. | |
| 20 The options "start" and "length" specify the input file. | |
| 21 The special option value length=max specifies all the input file from | |
| 22 the given start to its end. | |
| 23 The options "width" and "frstep" specify the input frames. | |
| 24 The width option is the framewidth of each input frame) and the frstep | |
| 25 option is the frameshift between input frames in the input file. | |
| 26 The special option value width=max specifies the input framewidth as equal | |
| 27 to the given input file length, (and if this is also "max", then the | |
| 28 input framewidth is the remainder of the input file). | |
| 29 | |
| 30 Most options in the input header are copied to the output header. | |
| 31 This enables options which are needed for the eventual display | |
| 32 to pass straight through. Some options are set so that they can override | |
| 33 the input header. For example, the display option is set on to enable | |
| 34 display even when input has display=off. The animate option can be set on | |
| 35 even when the input has animate=off. | |
| 36 Some parts of the header are changed for the output format: | |
| 37 (frames, frameshift, framewidth, frameheight, framebytes). | |
| 38 | |
| 39 Each row of each input frame is padded with zeroes to the next power of 2 | |
| 40 larger than the original input framewidth. | |
| 41 If necessary, extra padding can be enforced using the (silent) padding option | |
| 42 to add extra zeroes, padding to a larger power of 2. | |
| 43 The amount of extra padding is "exponential", expanding the basic size to: | |
| 44 | |
| 45 ( framewidth + padding ) * 2**n | |
| 46 | |
| 47 where the padding option is n. | |
| 48 | |
| 49 (n=0 by default, so that no extra padding is added. When n=1 then padding is | |
| 50 added to double the size, and when n=2 the size is quadrupled, etc.). | |
| 51 The output framewidth (and hence the frequency resolution) depends upon the | |
| 52 input framewidth and the padding. | |
| 53 | |
| 54 | |
| 55 .SH EXAMPLES | |
| 56 1. ftgram of a NAP, animated, with framewidth 16ms | |
| 57 | |
| 58 gennap len=128ms output=stdout display=off file | ftgram width=16ms \ | |
| 59 animate=on > file.sai | |
| 60 | |
| 61 gensai useprev=on headr=5 top=1000 file -(for landscape plot) | |
| 62 | |
| 63 genspl useprev=on headr=5 top=1000 pensize=2 file -(for spiral plot) | |
| 64 | |
| 65 2. ftgram of an SAI: | |
| 66 (gensai removes file.sai, so you must use some other name, eg foo.sai). | |
| 67 | |
| 68 gensai len=64 pwidth=64 nwidth=0 output=stdout display=off file | \ | |
| 69 saitonap frame=3 | ftgram width=32ms frame=1 > foo.sai | |
| 70 | |
| 71 gensai useprev=on top=1000 headr=5 mag=2 foo | |
| 72 | |
| 73 | |
| 74 .SH COPYRIGHT | |
| 75 .LP | |
| 76 Copyright (c) Applied Psychology Unit, Medical Research Council, 1995 | |
| 77 .LP | |
| 78 Permission to use, copy, modify, and distribute this software without fee | |
| 79 is hereby granted for research purposes, provided that this copyright | |
| 80 notice appears in all copies and in all supporting documentation, and that | |
| 81 the software is not redistributed for any fee (except for a nominal | |
| 82 shipping charge). Anyone wanting to incorporate all or part of this | |
| 83 software in a commercial product must obtain a license from the Medical | |
| 84 Research Council. | |
| 85 .LP | |
| 86 The MRC makes no representations about the suitability of this | |
| 87 software for any purpose. It is provided "as is" without express or | |
| 88 implied warranty. | |
| 89 .LP | |
| 90 THE MRC DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING | |
| 91 ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL | |
| 92 THE A.P.U. BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES | |
| 93 OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, | |
| 94 WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, | |
| 95 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS | |
| 96 SOFTWARE. | |
| 97 |