Speech:Corpus


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Project Notes

 * Unix Notes
 * Active Directory
 * Backups
 * Network Bridge
 * Speech S/W Installation
 * [Speech Corpus Setup]
 * Switchboard Data Notes
 * Experiment Setup
 * Scripts Page
 * Model Building
 * Step 2: Run a Train
 * Step 2: Create the Language Model
 * Step 3: Run the Decode

Speech Corpus
A speech corpus (or spoken corpus) is a database of speech audio files and text translations. Transcriptions, in the linguistic sense, are the systematic representation of language in written form. In Speech technology speech corpora are used, among other things, to create acoustic models. An acoustic model is created by taking audio recordings of speech, and their text transcriptions, and using software to create statistical representations of the sounds that make up each word. It is used by a speech recognition engine to recognize speech. There are two types of Speech Corpora (corpora is the plural of corpus): Read Speech - which includes: Spontaneous Speech - which includes:
 * Book excerpts
 * Broadcast news
 * Lists of words
 * Sequences of numbers
 * Dialogs - between two or more people
 * Narratives - a person telling a story
 * Map-tasks - one person explains a route on a map to another
 * Appointment-tasks - two people try to find a common meeting time based on individual schedules

Making the directories
To create the needed folders we went to where they were going to be located in command line and the used the MD command to create the new folders, an example is MD corpus. This command can be used to create multiple folders at once as long as they are at the same location. An example of this is creating the full and mini folders, MD full mini. /mnt/main/corpus/switchboard> MD full mini

Once the folders were created the ownership of the folders was changed, using root access, to root using the chown command which changes the ownership of a folder. /mnt/main/corpus/switchboard> chown root full

The group ownership of the folders was also changed to cis790 using the chgrp command. /mnt/main/corpus/switchboard> chgrp cis790 mini

The command ls -l can be used to view folder permissions and ownerships. /mnt/main/corpus/switchboard> ls -l total 8 drwxr-xr-x 5 root cis790 4096 2012-03-06 03:24 full drwxr-xr-x 5 root cis790 4096 2012-03-06 03:25 mini

The Switchboard directory in /mnt/main/corpus/dist is a redirected directory from /media/data/Switchboard. We used the ln –s command, which is symbolic link command.

Perl Scripts
1.The Perl script that is being used to complete everything that needs to be completed is *[[Speech:GenTrans| GenTrans].]

SOX
1. The syntax that will create a .wav file from a specified time range in the .sph file is: sox old.wav new.wav trim [SECOND TO START] [SECONDS DURATION]

For an example of this syntax I used:

sox sw02001.sph 02001.wav trim 64 7

It then created a .wav file where file sw02001.sph had an utterance starting at 64 seconds and lasted 7 seconds.

Commands
1. To create symbolic (soft) links from one file to another file the ln -s command is to be used.

ln -s ../disk1/swb1/*.sph -t.

This command will go back one directory and navigate to disk1 and then to swb1. It then will grab all the files ending with .sph. The -t is the target directory which in this case was the folder that I was running the command from. This command was being ran from /mnt/main/corpus/dist/Switchboard/flat. Since it was being ran from the flat folder it had to navigate backwards, hence the .. at the beginning of the command, to the disk1 directory.