4.1 The Command Line

 

The general form of command line for invoking a tool is   

	   tool [options] files ...

Options always consist of a dash followed by a single letter. Some options are followed by an argument as follows

 
			     -i 		  - a switch option

			     -t 3 		 - an integer valued option

			     -a 0.01 		 - a float valued option

			     -s hello 		 - a string valued option

Option names consisting of a capital letter are common across all tools (see section 4.4). Integer arguments  may be given in any of the standard C formats, for example, 13, 0xD and 015 all represent the same number. Typing the name of a tool on its own always causes a short summary of the command line options to be printed in place of its normal operation. For example, typing

    HERest

would result in the following output

    USAGE: HERest [options] hmmList dataFiles...

     Option                                   Default

     -c f    Mixture pruning threshold          10.0
     -d s    dir to find hmm definitions       current
     -m N    set min examples needed per model   3
     -o s    extension for new hmm files        as src
     -p N    set parallel mode to N             off
     ...

The first line shows the names of the required files and the rest consists of a listing of each option, its meaning, and its default value.

The precise naming convention for specifying files depends on the operating system being used, but HTK always assumes the existence of a hierarchical file system and it maintains a distinction between directory paths and file names.

In general, a file will be located either in the current directory, some subdirectory of the current directory or some subdirectory of the root directory. For example, in the command

      HList s1 dir/s2 /users/sjy/speech/s3

file s1 must be in the current directory, s2 must be in the directory dir within the current directory and s3 must be in the directory /users/sjy/speech.

Some tools allow directories to be specified via configuration parameters and command line options. In all cases, the final path character (eg / in UNIX, : in Mac OS) need not (but may be) included. For example, both of the following are acceptable and have equivalent effect

      HInit -l i: -L mymodels/new/  hmmfile data*
      HInit -l i: -L mymodels/new  hmmfile data*

where the -L option specifies the directory in which to find the label files associated with the data files.