This section summarises the environment variables and configuration parameters recognised by HSHELL, HMEM and HMATH. It also provides a list of all the standard command line options used with HTK.
Table 4.1 lists all of the configuration parameters along with a brief description. A missing module name means that it is recognised by more than one module. Table 4.2 lists all of the environment parameters used by these modules. Finally, table 4.3 lists all of the standard options.
| Module | Name | Description |
| HSHELL | ABORTONERR | core dump on error (for debugging) |
| HSHELL | HWAVEFILTER | Filter for waveform file input |
| HSHELL | HPARMFILTER | Filter for parameter file input |
| HSHELL | HLANGMODFILTER | Filter for language model file input |
| HSHELL | HMMLISTFILTER | Filter for HMM list file input |
| HSHELL | HMMDEFFILTER | Filter for HMM definition file input |
| HSHELL | HLABELFILTER | Filter for Label file input |
| HSHELL | HNETFILTER | Filter for Network file input |
| HSHELL | HDICTFILTER | Filter for Dictionary file input |
| HSHELL | HWAVEOFILTER | Filter for waveform file output |
| HSHELL | HPARMOFILTER | Filter for parameter file output |
| HSHELL | HLANGMODOFILTER | Filter for language model file output |
| HSHELL | HMMLISTOFILTER | Filter for HMM list file output |
| HSHELL | HMMDEFOFILTER | Filter for HMM definition file output |
| HSHELL | HLABELOFILTER | Filter for Label file output |
| HSHELL | HNETOFILTER | Filter for Network file output |
| HSHELL | HDICTOFILTER | Filter for Dictionary file output |
| HSHELL | MAXTRYOPEN | number of file open retries |
| HSHELL | NONUMESCAPES | prevent string output using \012 format |
| NATURALREADORDER | Enable natural read order for HTK binary files | |
| NATURALWRITEORDER | Enable natural write order for HTK binary files | |
| HMEM | PROTECTSTAKS | warn if stack is cut-back (debugging) |
| TRACE | trace control (default=0) |
| Env Variable | Meaning |
| HCONFIG | Name of default configuration file |
| HxxxFILTER | Input/Output filters as above |
| Standard Option | Meaning |
| -A | Print command line arguments |
| -B | Store output HMM macro files in binary |
| -C cf | Configuration file is cf |
| -D | Display configuration variables |
| -F fmt | Set source data file format to fmt |
| -G fmt | Set source label file format to fmt |
| -H mmf | Load HMM macro file mmf |
| -I mlf | Load master label file mlf |
| -L dir | Look for label files in directory dir |
| -M dir | Store output HMM macro files in directory dir |
| -O fmt | Set output data file format to fmt |
| -P fmt | Set output label file format to fmt |
| -Q | Print command summary info |
| -S scp | Use command line script file scp |
| -T N | Set trace level to N |
| -V | Print version information |
| -X ext | Set label file extension to ext |
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