Praat scripting basics

Pauline Welby Col áiste na Tríonóide, Baile Átha Cliath (Irlanda) [email protected]

Praat scripting

• Praat is a phonetic analysis software program • Available for many different platforms (Windows, Macintosh, Unix, Linux) • Can be downloaded (for free) from www.praat.org. • Includes a scripting language

Praat scripts

• Do anything you can do in Praat by hand – Open, save, rename files, convert formats, etc.

– Measure formants, F0, etc.

– Resynthesize duration, F0, etc.

– Draw figures – Label – Present stimuli and collect responses

Why script in Praat?

• saves time • prevents errors (typos, data transfer errors) • makes errors easier/faster to correct • allows you to play around with different parameters

Detailed Praat scripting tutorial

Available on the web (Praat web page): http://www.fon.hum.uva.nl/praat/manual/Scripting.html

or From within Praat In objects window: Help | Praat intro Search: scripting

Keep in mind…

• It’s easier to adapt an existing script (your own or someone else’s) than to write one from scratch.

• Many scripts freely available on the Web Check sites: – http://www.icp.inpg.fr/~welby/PAGES/praat.html

(Pauline Welby, in French and English) – http://www.cavi.univ-paris3.fr/ilpga/ED/student/stcg/#E (Cedric Gendrot, in French) – http://www.helsinki.fi/~lennes/praat-scripts (Mietta Lennes, in English) – http://www.icp.inpg.fr/%7Eloeven/ScriptsPraat.html

(Hélène Loevenbruck, in French) – http://www.cphling.dk/pers/johtnd/praat/my_praat.htm

(John Tøndering, in English) – http://www.ling.ohio-state.edu/~kyoon/scripts/praat (Kyuchul Yoon, in English) Also, try a Google search.

Opening a Praat script

• To open an existing script in Praat: Praat | Open script... • Note: Different from opening sound files, TextGrid files etc. (Read | Read from file…)

Let’s try it…

• Open (read in) all sound files in a directory • Can do by hand (slowly and painfully) • Or use a script: readin-files-simple.praat

- Praat | Open script...

- Navigate to correct directory and find readin-files-simple.praat

Open the script: Starter1.praat

Elements in a script

Comments • Allow you to give descriptions of what each part of a script does – A very good idea! Helps you (and other users) understand how the script works • Also useful for testing and diagnostic purposes • Praat comment character: # • Praat ignores anything to the right of # • This line reads in a sound file: Read from file... finger.wav

• This line does nothing!

#Read from file... finger.wav

Elements in a script

• Objects (are manipulated) – everything in object window (at left) – files – numbers – strings (letters, etc.) …

Open the script: Starter2.praat

Elements in a script

• Variables (a type of object) – Store values – Examples: • ifile • numberOfFiles • fileName$ – Types: number, string (text), boolean (yes/no or 1/0) – Naming conventions: • begin with lowercase letters • no spaces • string variables must end in ‘$’

Open the script: Starter3.praat

Elements in a script

• Functions (exist in Praat window menus) – Read from file… – Write to file… – Remove – Play Some functions act on only certain types of objects and in certain environments (e.g., Edit window).

Naming conventions: - always begin with uppercase letters - may have spaces functions that take arguments end in dots (…)

Elements in a script

• Commands (specific to Praat scripting language) – form, endform – select – print – clearinfo – if, endif – for, endfor … Naming conventions: - start with lowercase letters - one word

Creating a Praat script from scratch

• To create a new script: Praat | New script

History

• Praat keeps track of what you do by hand • If you want to do something, but you’re not sure of the syntax, do : – in script window: Edit | Clear history – in objects window, select the object you want to work on and perform the operation. (Query | Get duration) – in script window (Edit | Paste history)

Open the script: Starter4.praat

Loops

• Allow the same commands and functions to be executed over and over again (on a list of files, for example) • Created with: for, endfor repeat, until (and other pairs of commands)

Bug tracking

• Error messages can be transparent… • But often are not!

• Practice fixing errors by introducing them: – missing $, misspelled/wrong case variable, hard return in form, … • Use print command to print information to info window and find bugs. E.g.: – print got here 'newline$’ – print ‘baseFile’ 'newline$’ • Make changes and test incrementally • Save a backup script that works

Be (very!) careful…

• … not to overwrite or delete important files!

• Scripts are powerful and one mistake can wipe out days (weeks, months…) of work in seconds • Keep backups of data • When writing/adapting a new script, work in a temporary directory

Acknowledgments

• Slides on element types based on Praat scripting tutorial basics, Florian Jaeger http://www.stanford.edu/~tiflo/teaching/tutorials/T_Jaeger _042104-praat%20scripting.htm#slide0001.htm

• My new lab (as of October 1, 2008) Laboratoire Parole et Langage Aix-en-Provence, France • My e-mail address will be: [email protected]