man.diff

来自「speech signal process tools」· DIFF 代码 · 共 210 行

.\" Copyright (c) 1988,1990 Entropic Speech, Inc.; All rights reserved
.\" @(#)zcross.1	1.8 8/10/91 ESI
.TH ZCROSS 1\-ESPS 8/10/91
.ds ]W "\fI\s+4\ze\h'0.05'e\s-4\v'-0.4m'\fP\(*p\v'0.4m'\ Entropic Speech, Inc.
.SH "NAME"
zcross \- computes average zero-crossing rate for sampled data in FEA records 
.SH "SYNOPSIS"
.B zcross
[
.BI \-P " params"
] [
.BI \-f " sd_field"
[
.BI \-f " zeros_field"
]] [
.BI \-r " range"
] [
.BI \-x " debug_level"
]
.I "input output"
.SH "DESCRIPTION"
.PP
.I Zcross
accepts a FEA file \fIinput\fP containing a vector sampled-data field
in each record.  It produces a FEA file \fIoutput\fP with records
containing the average zero-crossing rate of the sampled-data field
from that record.  Each field of sampled data may be thought of as a
separate frame of data, such as might be produced by \fIframe\fP
(1\-\s-1ESPS\s+1).  The default name for the sampled data field in
\fIinput\fP is \fIsd\fP, and the default name for the zero-crossing
field in \fIoutput\fP is \fIzero_cross_rate\fP.  Both defaults can be
changed by means of the \fB\-f\fP option.  If \fIinput\fP is "\-",
standard input is used for the input file.  If \fIoutput\fP is "\-",
standard input is used for the output file.
.PP
The zero-crossing rate is computed by multiplying the number of zero
crossings by the sampling frequency and dividing by the number of samples
in the frame.  Thus, the units are zero-crossings per second.  If
\fIinput\fP is not a segment-labelled FEA file (see FEA (5\-\s-1ESPS\s+1)),
the frame is considered to comprise all of the points in the sampled data
field, so the frame length is a constant set to the size of the sampled
data field (which can be determined from the file header).  If \fIinput\fP
is segment-labelled, the size of the sampled data field is really a maximum
size, and the frame size for a particular record is given by the
\fIsegment_length\fP field (this field is always present in
segment-labelled files).  Thus, for segment-labelled files, the frame from
any input record is the first \fIsegment_length\fP points of the sampled
data field.
.PP
The sampling frequency is determined by the generic header item
\fIsrc_sf\fP from \fIinput\fP.  If this generic header item doesn't exist,
the sample frequency is set to 1 so that the zero-crossing rate is reported
in units of crossings per sample.  (Note that you can always use
\fIaddgen\fP (1\-\s-1ESPS\s+1) to put in the correct sampling frequency if
it is missing.)
.SH OPTIONS
.PP
The following options are supported:
.TP
.BI \-P " param" " \fR[params]\fP"
Specifies the name of the parameter file.
.TP
.BI \-r " start" : "last" "\fR [1:(last in file)]"
.TP
.BI \-r " start" :+ "nan"
In the first form, a pair of unsigned integers specifies the range
of records to be processed.
Either
.I start
or
.I last
may be omitted; then the default value is used.
If
.IR last " = " start " + " nan,
the second form (with the plus sign) specifies the same range as the first.
The \fB\-r\fP overrides the values of \fIstart\fP and \fInan\fP from 
the parameter file.  
.TP
.BI \-f " field_name" 
If this option is used once, it specifies the name of the sampled data
field in \fIinput\fP.  If it is used twice, the second time it specifies
the name of the power field in \fIoutput\fP.  The default names for these
fields are "sd" and "zero_cross_rate", respectively.
.SH "ESPS PARAMETERS"
.PP
The parameter file does not have to be present,
since all the parameters have default values.
The following parameters are read, if present, from the parameter file:
.IP
.I "sd_field_name \- string"
.IP
This is the name of the sampled data field in \fIinput\fP.
The default is "sd".  A parameter file value (if present) is overridden
by the first use of the \fB\-f\fP option.  
.IP
.I "zcross_field_name \- string"
.IP
This is the name of the raw power field in \fIoutput\fP.  The default is
"zero_cross_rate".  A parameter file value (if present) is overridden by
the second use of the \fB\-f\fP option.
.IP
.I "start \- integer"
.IP
This is the first record of \fIinput\fP to process.  The default is 1.  It
is not read if the \fB\-r\fP option is used.
.sp
.I "nan \- integer"
.IP
This is the number of records to process.  It is not read if the \fB\-r\fP
option is used.  A value of zero means all subsequent records in the file;
this is the default.
.PP
Remember that command line option values override 
parameter file values.
.SH "ESPS COMMON"
.PP
ESPS Common processing may be disabled by setting the environment variable
USE_ESPS_COMMON to "off".  The default ESPS Common file is .espscom 
in the user's home directory.  This may be overridden by setting
the environment variable ESPSCOM to the desired path.  User feedback of
Common processing is determined by the environment variable ESPS_VERBOSE,
with 0 causing no feedback and increasing levels causing increasingly
detailed feedback.  If ESPS_VERBOSE is not defined, a default value of 3 is
assumed.
.PP
ESPS Common is not processed by 
.I zcross
if \fIinput\fP is 
standard input.  Otherwise, provided that the Common file is newer 
than the parameter file, and provided that the \fIfilename\fP entry in 
Common matches \fIinput\fP, the Common values for \fIstart\fP and 
\fInan\fP override those that may be present in the parameter file. 
.PP
The following items are written into the ESPS Common file 
provided that \fIoutput\fP is not <stdout>.  
.IP
.I "start \- integer"
.IP
The starting point from the input file.
.sp
.I "nan \- integer"
.IP
The number of points in the selected range.
.sp
.I "prog \- string"
.IP
This is the name of the program 
.RI ( zcross
in this case).
.sp
.I "filename \- string"
.IP
The name of the input file \fIinput\fP.
.SH ESPS HEADERS
.PP
The \fIoutput\fP header is a new FEA file header.  If the generic
header item \fIsrc_sf\fP exists in the input file, it is copied to the
output file if it exists (otherwise it is set to 1).  The items
\fIstart\fP and \fInan\fP are written to contain the starting record
number and number of records processed.
.PP
The size of the input sampled data field is written to the generic 
\fIfrmlen\fP.  
.PP
The generic header item \fIstart_time\fP is written in the output
file.  The value written is computed by taking the \fIstart_time\fP
value from the header of the input file (or zero, if such a header
item doesn't exist), adding to it the relative time from the first
record in the file to the first record processed, and adding a
displacement corresponding to half of \fIfrmlen\fP.  The computation
of \fIstart_time\fP depends on the value of the generic header item
\fIsrc_sf\fP in the input file (which is assumed to be the sampling
rate of the actual data in each field).  If this item is not present,
\fIstart_time\fP is just copied from the input file to the output
file.
.PP
As usual, the command line is added as a comment and the header of
\fIinput\fP is added as a source file to \fIoutput\fP.  Another
comment gives the name of the field added by \fIzcross\fP.
.SH "FUTURE CHANGES"
.PP
Control over the type of the output power field.  
.SH "SEE ALSO"
.PP
\fIframe\fP (1\-\s-1ESPS\s+1), FEA (5\-\s-1ESPS\s+1), \fIfea_stats\fP
(1\-\s-1ESPS\s+1), \fIpwr\fP (1\-\s-1ESPS\s+1), \fIwindow\fP
(1\-\s-1ESPS\s+1), \fIaddgen\fP (1\-\s-1ESPS\s+1), \fIstats\fP
(1\-\s-1ESPS\s+1) 
.SH "WARNINGS AND DIAGNOSTICS"
.PP
.I zcross
will exit with an error message if any of the 
following are true: 
.I input
does not exist or is not an ESPS FEA file; 
the sampled-data field does not exist in
.I input;
the power field already exists in
.I input.
.PP
.I Zcross
will warn if the generic \fIsrc_sf\fP doesn't exist in \fIinput\fP. 
.SH "BUGS"
.PP
None known.  
.SH "AUTHOR"
.PP
Manual page and program by John Shore.