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rPraat and mPraat: Connect Praat, Matlab, and R

rPraat and mPraat We are introducing rPraat and mPraat, which interfaces acoustic analysis in Praat (the most popular software for phonetic analyses) with the possibilities of general tools, R and Matlab.
Read, write, create, manipulate, and plot Sound, TextGrid, PitchTier, IntensityTier, Pitch, and Collection files from Praat in R and Matlab.

rPraat and mPraat (project home page)


Fourier Series 3D - demonstration (Discrete Fourier Transform in 3D, FFT)

Fourier series 3D square Fourier Transform 3D (Discrete Fourier Transform 3D demonstration) Demonstration of Fourier Series in 3D (in fact, it is Discrete Fourier Transform in 3D, FFT). It is easy to understand the connection between time and frequency domain. All in one 3D picture: time axis, frequency axis, amplitudes, and phases. Everything is interactive - you can drag amplitudes, phases, draw your own signal, change number of harmonics, turn on sound and listen to the impact of the actions. And more (only in Java version) - you can go to tutorial section and watch and listen to a lot of interesting commented automatic demonstrations.
Predefined signals: Sine, cosine, square (rectangle), triangle, sawtooth, beats, sine impulse.
Tutorial experiments: Gibbs phenomenon (Gibbs effect), harmonics and sharpness, discontinuity and sharpness, f0 (fundamental frequency), tone color, DC component, sampling theorem, hearing range, phase and perception, beats, make your own instrument, sine impulse (intro to Fourier transform), vowels (synthetic voice), Shepard tone (infinite music scale).

Fourier Series 3D demonstration (project home page)


TB Strobe Tuner (Software Strobe Tuner for PC with Windows)

Zoom in What is strobe tuner? The stroboscopic tuning is the most accurate music instrument tuning with the precision of 0.1 cents! In contrast to common chromatic tuners, the stroboscopic effect works in a time domain, therefore the response is instance and the tuning accuracy is more than 10x higher!

Do I need the 0.1 cents precision? Most of the people with perfect pitch deprecate common chromatic tuners. If you have an instrument with more strings (like guitar) you will notice that with the strobe tuner the chords sound better.

Key features

For more information and free full version download, please visit TB Strobe Tuner homepage:


Music Notes Training - Noty 2013

Zoom in Effective way of learning music notes in treble and bass clef for piano, guitar and other instruments.

It shows random notes, you have to tell the right name of the note and play it on your instrument. After a delay it plays and shows you the correct answer. Please note - the 'H' is the name for 'B' note in Czech Republic and Germany.

Download Music Notes Training - Noty 2013: installation .exe file.


PhonoDash - phonetic game for 1 or 2 players

PhonoDash Phonetic game for one or two players, clone of famous BoulderDash game. It was developed by a team of Programming II 2013/2014 course at Institute of Phonetics, Prague.

Go to PhonoDash webpage (Institute of Phonetics, Prague).

Let's play PhonoDash.


Learning - vocabulary, pictures of plants etc.

Zoom in Learn vocabulary, recognize plants from pictures etc. This app delivers new items randomly in batches (so-called group 'I do not know') and after proper acquiring, they are moved to a group 'Learned' and new items are moved from the entire big lesson (group 'Queue'). The random order is important as well as the batch of new items in small groups. It would not be a good idea to overload the problem with new items all at once.

The size of the group 'I do not know' can be adjusted as well as a probability of verification of the 'Learned' group items.

The program can be terminated at any time as it remembers its position. More users can share the same PC, user accounts are created.

Direction of examination can be set (like 'show name' or 'show picture') and for each direction, the state of 'Learned', 'I do not know' and 'Queue' groups is saved separately.

New lectures can be created easily in a notepad with optional links to images or sound files.

The evaulation of answers is also unique. Based on positive experience with Music Notes Training - Noty 2013) program, the user does not input the answer. The answer is only uncovered after the press of a button and the user self-evaluates whether the answer is correct or not. This approach has several advantages: it supports good temper, it is very fast if the user knows the answer. And when the user is smarter then the computer (knows more correct answers), the computer does not penalize it with frustrating evaluations like 'you entered an incorrect answer'. This is especially important in vocabulary lectures where many synonyms may exist naturally. When the user is motivated, this approach is very efective. And the program tries to encourage the user in his/her motivation.

Learning tool Phoenix at Institute of phonetics webpage.


RDSync 2007 (Remote Directories Synchronization)

Zoom in I have my personal folder with all my files. The problem is that I have one computer at home and another one at student's hostel. I move between these two computers frequently and I need my folder exactly in the same state as on the other computer which I have left. A solution is to burn the folder to DVD and copy it to the other computer. But the size of folder is much more greater than the DVD capacity and it takes a lot of time and why should I copy the files which are not changed?

That is why I have made RDSync. It analyses the structure of the folder and it copies only the differences - new files and changed files and it removes the files which I have deleted. So I only burn the differences on my DVD-RW, it is very cool. I have both computers exactly synchronised. All the time I have the feeling that I work on 'my' computer with all my files up to date.

The unique feature of RDSync is that the other computer can be turned off, offline. The whole structure of the remote synchronisation folder is saved in one 'fingerprint' .RDS file with all needed info. So I can make folder with differences even when the remote computer is not online. The another good feature is that it supports unicode file names.


H&T Recorder (Lombard effect voice recording in artificial noise conditions)

Zoom in I have made H&T Recorder for my brother Hynek Bořil, graduate student from The Circuit Theory department, Speech Processing Group (CTU in Prague).

The main features are simple operation, high reliability and nice look. It is used for recording the speech with Lombard effect, it is the speech in noisy and stress conditions.

The noise is played to headphones so we can record the clean Lombard effect voice without disturbing noise. We used two microphones and two headphones so two soundcards are necessary. The hardest thing was to bring a voice from one microphone to the phones on the other soundcard with a minimal delay. The program uses DirectSound and DirectX .Net.


Analytic Geometry

Screenshot We learned analytic geometry in the second grade in my secondary school. I have made Analytic Geometry program for my calculator TI-89 to help me with calculations. It is very comprehensive program. You can input points, vectors, lines and planes and calculate a lot of things, like angels, intersections etc.

Download Anageom 2.2 Pro. You need the TI-89 emulator to run it on a PC, it is also in the .zip file.
Download the Anageom 2.2 Pro tutorial. Step by step instructions how to use Anageom 2.2 Pro.


Spirograph in R, export to .pdf, svg and .gcode

Zoom in Legendary spirograph, my favorite toy, now in R with export to vector formats .pdf, .svg, and .gcode for plotter and CNC engraving.

Spirograph in .R source code and gallery.


Circuit Editor

Zoom in It is the second semestral work in Java course in the first grade in CTU Prague university. You can draw electric circuits, set their properties, save it and print it. You can make selections and then move them or set common properties.

Download Schemedit.
There is a problem with compatibility. It is made in JBuilder 9 Personal with Java jdk1.4. In newer versions of java there is a problem with rendering popup menus - they are covered by the drawing canvas. If you have any idea how to repair it, let me know, please. Thanks!



Zvětšit I have an mp3 player iAudio U3 which cannot play m3u playlists. M3uCopy reads the m3u playlist and copies the songs from PC to the target folder (eg. directly to the mp3 player) and adds numbers before the filenames according to the order in the m3u list.

Download m3uCopy. You need .Net Framework.


Winter Game

It is my first semestral work in Java course in the first grade in CTU Prague university. It is Czech text game.

Download Winter Game. There are two versions - if you have Java, I recommend to run 'Spusť v Javě.bat'. Or you can use 'Zimní hra.exe', it is compilated in MS-DOS Borland C++.


Print a Book

Zoom in With Print a Book, it is easy to print a book :-)

The book is made from 10 sheets brochures which are glued together to one backbone. Each sheet contains 4 pages, 2 on each side. Sheets are folded in a half and stapled together.

How to print pages? You have to print doublesided. And this program tells you the sequence of the pages. At the first step you print one side and then the reverse side.

Download Print a Book. You need .Net Framework.


Master Mind

Screenshot If you know Master Mind, you can play the game with this program but it also helps you a lot with analyses!

Each random digit is from 1 to 8. And you try to guess. The first digit of the result tells you how many digits are right and on the right position. The second number tells you how many of the rest of right digits are on the wrong positions. But you do not know which digits are these. And that is the trick of the game.

Start the Master Mind. Write any integer in the Počáteční RAN# textbox, it is the random number generator seed. Click on Nová hra. And you can start guessing. Write your tip in the Odhad textbox and press Hodnocení. You will see the result in Hodnocení textbox. If it is 40, you win!

If you want use computer analysis, each time after clicking Nová hra, click also on Znovu button. And each time after clicking Hodnocení, click also on Vyhodnoť. In the left list you can see all possible solutions.

Download Master Mind. You need .Net Framework.


Backup System

I made it in 2004 for Skoda auto, Mladá Boleslav. It is backup system for creating differential backups.

It is developed in MS Visual C++ and the main features are absolute reliability and command-line operating for batch use. It is not acceptable to make invalid operation or not to respond correctly to exceptional state. Everything must be reported. The long unicode file names and UNC paths are naturally supported.

If you are interested in this backup system, contact me, please.


Synthesizer for Linux

I made it during winter in 2002 and 2003. My brother Hynek Bořil was working on diploma thesis on CTU in Prague on a unique algorithm for realtime reliable f0 estimating. He used it for an eletric guitar synthesizer under Linux but it is also used for very reliable voice f0 estimation. He played on the electric guitar with 6 string pickup and the computer was playing with minimal delay with the sound of electric organ.

He made the algorithm in Matlab and I translated it into the C++ under Redhat Linux. It works amazingly with a minimal delay (only few ms).


Visual Baltazar 5.0

Zoom in When I was 17 years old, it was in 2001, I programmed this thing for programming competition in children programming language Baltazar 5.0 for MS-DOS. It is similar to C, it is not object language. I made a SDK and kernel for developing and running GUI programs.

It is possible to create forms, buttons, scrollbars, images, check buttons and textboxes. Selections and clipboard are supported. My kernel analyses all events all the time, redraws all graphics and calls event handlers.

It was not easy to build this project - the kernel must draw everything from beginning - points, lines, rectangles etc. So we can say that I made Windows-Lite :-)

Download Czech documentation for Visual Baltazar 5.0.



Zoom in I made Thermometer on my secondary school and it is my first program in object language C++.

It works under MS-DOS but it is user friendly. I made it for my brother - he made HW part for his semestral work on university and I made SW part. It communicates via parallel LPT port.

The program records temperatures in time, it plots them, saves them, you can zoom data and show statistic values.

Download Czech documentation for HW part of thermometer.



Zoom in My first job - during summer holidays between my primary and secondary school. It is made to order for one company. It is in C++ under MS-DOS. It monitors signals from a lot of units and it analyses them and displays various operating states.

There is also a table editor with some important values. The user interface is very friendly and my submitter was satisfied.


ZOO Editor

Zoom in We had a project on primary school. The task was to make WWW presentation of ZOO Liberec. The project was terminated but my part of job was well-done.

Me and my friend Lukáš Bajer made a program for collecting datas of animals. We made it but there were some bugs. And that is why I made the program once more from the beginning.

It is made in historical Visual Basic 3. It generates main structure of informations and user can add more informations, it is similar to xml format. If items are added in incorrect sequence, it can be automaticaly sorted.

The interesting feature is that it can check if the items are inputed in correct format. If something is wrong, program explains it deeply to the user (you can see it on a screenshot).


Game Had 99 (Snake)

Zoom in We were not allowed to play games instead of self-made on primary school. That is why I made one :-) Yeah, it is the legendary snake game. You can go through the edges, you will appear on the opposite side, it is funny.

There are 20 levels and I am telling you - you cannot do them all, it is so hard :-)

It is made in TASM assembler with 8086 instruction set and MS-DOS services.

Download iso-boot version CD (DVD) with snake game HAD 99. It works everywhere and it is independent of your OS. And it is only 1.5 MB.
Download original HAD 99. It does not work under Windows XP.


Czech 'y/i' Training

Zoom in My competition program in children programing language Baltazar 5.0 for MS-DOS.

It teaches you the right czech 'y' and 'i' spelling.

Download BLMPSVZ. It is for MS-DOS but it works well under Windows XP.


Game Bombák (Bomber)

Screenshot Funny action game which was made by our team on primary school in only one week!

Your task is to bomb a town and land safely.

It is programmed by me and my friend Lukáš Bajer in Visual Basic 3. Other team members made graphics.

Download Bombák. You have to use deafault 'small fonts settings' in your Windows.
Warning! There are very loud sounds, turn down your loudspeakers please!!!

Note: in present time the game is little bit faster than earlier. So the game is more hard than before :-)


Game Squares

Zoom in This is a logic game. And it is my first large program in C language under PC. Before that I made programs under Sinclair ZX Spectrum.

Your task is to clear all the squares. When you click on a square, it is inverted. But also the neighbours are inverted, that is the trick.

Download game squares (Ctverce). It is for MS-DOS but it works well under Windows XP.


Game Formula

Zoom in My only extant program from Sinclair ZX Spectrum era!

I started to learn programming when I was 7 years old. I made a lot of small programs in Basic.

The game Formula is my last and the best program on Sinclair ZX Spectrum. I finished it on the 1st September 1995, the day when the summer hollidays ends. The day when I left the first part of primary school and started the second part on computer primary school.

The game is for two players. On ZX Spectrum the one car is controled by keyboard and the second one by Kempston Joystick. The task is to arrive in a short time to the finish with the less amount of penal points. When you hit a wall, you get a lot of these points! The finish is marked by the '#' symbol.

Thanks to a great free Java ZX Spectrum emulator, you can play this game on PC directly in your browser!
Warning: the emulator makes sometimes strange loud sounds, I recommend you to turn down your loudspeakers.
Play game Formula. You need Java plugin for your browser.

The game is in Czech language but it is easy to play - click on the emulator image, press ENTER, then press H, choose your controls (forward, left, right, stop) and press ENTER. The second player use arrows.