Fran Rojas' personal web page

HOME

ABOUT ME

APPLICATIONS

DOWNLOADS

QUERIES

GREETINGS

CONTACT

ONLINE CALCULATOR

APPLICATIONS

THIS PAGE NEEDS JAVASCRIPT TO WORK

Multiprecision calculator

v1.0.2

v1.1

v1.2

Lens effect

v1.1

v1.2

v1.3

Java File Encoder (encryptor)

v1.0

v1.1

v1.2

v1.3

v1.4

v1.5

Subtitle synchronization

v1.0

v1.1

Audio synchronization

v0.5

Filtering Google Sheets

v0.5

Chess PDF browser

( ChessPdfBrowser web site )

v1.0

v1.1

v1.11

v1.20

pdf2pgn

v1.20

Text encryption (Textcrypt)

v1.0

v1.0.2

v1.3

v1.4

v1.5

v1.6

Instrumental Music

v1.0

v1.1

v1.2

Platform libraries

v1.0

v1.1

v1.2

v1.3

v1.4

Icons

v1.0

Pdf Inspector

v1.0

Donut

v1.0

Music player

v1.0

Morphing Editor

v1.0

This is one of my first major applications developed using Java.

A new library to perform the calculations was written specifically for this application. The said library adopts the parameters of the class BigDecimal. Most of the main mathematical functions were programmed incorporating BigDecimal numbers with the chosen precision.

The final application has a text box where the operations to be calculated can be written on. It also allows storage of functions and variables.

The Graphic User Interface is quite simple but it has some errors which makes the application not user friendly. I am planning to design a new version of this application which will eliminate some of the bottle necks.

This is how it works: when the user writes the operation to be calculated, the application will make an analysis of that operation and will be stored in a tree structure. Formulas can be stored this way because the tree structure can be stored in the function of one or more variables. Once the tree structure of the formulas is constructed, the result of each operation is evaluated recursively until it yields the final result.

This is a new version of multiprecision calculator application.

Goals for the new version:

To improve the architecture of classes of the application.
Ability to calculate derivative functions in an algebraic way.
To improve the user interface.
To improve the help.

The main explanatoin for the new version has been to implement a calculator of derivatives.

The idea of this functionality comes from very long ago, when a teacher of highschool proposed us to participate to the annual software competition presenting an application that calculated derivatives.

In those times we could not make many advances in the project, but with this version of multiprecision calculator, almost 30 years after, the application that calculates derivatives comes :-).

There is wide handbook where it is explained how the application works.

The translator of this handbook is Tamara Perry

New version of multiprecision calculator application.

Goals:

To add new version query during start of the application for having a statistics of how many people uses it.
Dark mode option

There is wide handbook where it is explained how the application works.

This small application is called lens effect, developed during one of the Easter break without plans.

At that time, I was finishing the first version of the application called File Encoder Application and I needed something beautiful or colourful for the About page ...

The original idea is not mine but I implemented it using an effect that I saw many years ago in one of the legendary DOS demonstrations.

The implementation chosen was to encapsulate the effect inside a JPanel of Java Swing.

Everything inside the panel can be zoomed with the lens, which can be placed in any coordinates inside the panel.

It was especially hard to achieve the refresh of the text components (particularly when the location of the selected text is modified by the programme) without badly affect the visual effect.

Internally, it works in such a way that when the LensJPanel is created, it receives 3 parameters i.e. the content from JPanel which the effect will be made on, the lens radius and the zoom in and out effect.

With this information, a square matrix of two dimensions will be created where each pixel inside the square surrounding the lens.
For each of those pixels (destination pixels), the coordinates of the original image (source pixel) are calculated. This source pixel is the location inside the original image to be set in the destination pixel in the image with the lens effect done.
The transformation is a simple transformation in polar coordinates. I will explain that transformation for the case of the zooming out effect:
For a particular position inside the square surrounding the lens, an origin coordinate is calculated, as explained previously.
This source pixel will also be inside the square surrounding the lens. Besides that, each destination pixel will be translated to polar coordinates (radius and angle, from the center of the lens). The source pixel associated with every destination pixel, will have the same angle but the radius will change. The radius will be always within the range of 0% to 100% for both the destination pixels and source pixels. 100% is the length of the radius of the lens. That is, for every destination pixel, to calculate the source pixel the angle is maintained but the radius is transformed using a function with increasing monotonous derivative, inside the interval between 0 and 1, where f(0) will be 0 and f(1) will be 1, where 0 means 0% of the radius of the lens and 1 is the 100% of the radius of the lens. That means that the radius of the source pixel for a particular destination pixel will have a radius lesser than the destination pixel itself, which will make the lens to zoom out.
Outside the circle of the lens, the transformation will be the identity (that is, the destination pixel and the source pixel will be the same) so that outside the lens no zooming is done.

The explanation is a bit confusing, but if you are interested to know more, please contact me.

I hope it will be useful for someone :-)

The new version of the application opens a graphical window with the shape of a circle with the lens which can be moved by clicking with the mouse and dragging.

A couple of problems can be seen:

The background to be magnified cannot be refreshed very often because to get a snapshot of the screen (without the lens), the circular window must be transparent making an anoying flicker.
There is quite a lot of pixellation of the magnified image, over all at the central part of the lens.

The new version of the application fixes a bug of transparency that arose in Mac and Linux environments.

It also tries to solve the problem of pixellation present in previous versions.

This is achieved by passing a blurred gaussian filter to the image of the lens that decreases the pixellation.

The last subversión available of this versión of the application, works on both Java-8 and Java-11 Java versions.

This application was arisen because of a necessity of encrypting files with an own method.

You can encrypt files in a very configurable way, achieving encryptions really expensive in time, which makes difficult force brute attacks, that can be used to encrypt small files.

There is a user handbook quite talkative in which all details of working are explained, from the point of view of both, the user interface and internal to the application.

This version of the application was arisen due to that a change in the new version of the JRE of those times affected the look of the version v1.0 of the application. That is why version v1.1 arose.

The user handbook did not change with this version (it was the same as for the previous version).

For this version a couple of change were done:

Amendment of an error in the own pseudorandom generator used in the previous versions.
New encription types (specially designed to be used with big files) were created. With these new encrpytion types speed and robustness increased a lot.

There is a user handbook specific for this version, in which all details are explained.

In this version of the application several changes have been made:

New encryption type specially thought for big files, which increases the speed of encryption a lot, because it makes use of multiple execution threads.
New encryption type with which you can divide the encrypted file into volumes, in case there was any limitation with the size of the file in the output drive.
Zoom factor for the windows of the application to improve the viewing in devices with different pixel density.

There is a user handbook specific for this version, in which all details are explained.

The translator of this handbook is Tamara Perry

This version has arisen to try to avoid an error produced by the interaction with a new functionality of Java-9 which deals with screens with high density of pixels.

It also includes support for Maven.

There is a user handbook specific for this version, in which all details are explained.

The translator of this handbook is Tamara Perry

The goal of this version is to add new version query at start of the application for having some statistics of how many people uses it.

There is a user handbook specific for this version, in which all details are explained.

New dark mode option

This is the first version of a little application in Java that let help sincronize subtitles by applying a temporal factor to subtitle files of type (.srt).

The application autodetects the character set of the file of subtitles and allows choosing a new character set for the output (or using the encoding detected during the reading).

In this version some new things where added:

Help window
Support for English and Spanish
Suppor for files of type (.saa) besides the ones of (.srt) that were already processed in the previous version.
It adds the possibility to apply a delay in ms over the subtitles, besides the factor of the previous version.

This makes that, previously knowing the values of delay and factor, video and subtitles can be prefectly synchronized.

This application of command line was developed using C++ and allows to apply a time factor to audio files.

This operation implies that the input and output files will have different sizes and different duration).

The way to achieve this result is through interpolation of digital signals.

There is a very complete user handbook which explains about the user interface and the functions of the application.

This is a Java application which allows you to connect to Google Drive and read a spreadsheet.

After that, the application will presents the data in a JTable and allows using filtering function.

There is a complete user handbook in Spanish which explains step by step how to configure the application.

Chess PDF Browser is a Java application which allows browsing chess books in PDF format.

It also allows working with game files in .pgn format.

It shows a chess board which you can also browse the moves of the games.

It also allows opening the chess books in PDF format, extract their games and is able to save them in .pgn format.

Besides that, it allows to edit the movesof the games which is stored in the memory (either reading from a .pgn file, extracting from a PDF book or create directly the movement of the pieces on the board.

There is a wide user handbook where the user interface is explained.

With the new version of the application, some bugs have been fixed, and some new features have been added:

New experimental chess game parser.
Now you can set moves as novelties.
Support for Russian language.

There is wide user handbook where you can see how the application works.

With the new version of the application, user handbooks have been updated.

There is wide user handbook where you can see how the application works.

With the new version of the application some new features have been added:

Experimental game extractor has been replaced by a new one that takes into account brackets and square brackets.
A new feature that gets data from the games (chess player names, ELOs, etc.) has been enabled.
The possibility of viewing the games in algebraic figurine notation has been added.
An ocr is added to try to recognize the position of chess boards.
Now you can play games against another person or against an engine, or make two engines play.

Connection to UCI engines:
- Modifying the configuration of engines is allowed (as instance, it may be useful to lower the level of engine for playing against a level under the maximum.)
- Position analysis.
- Whole game analysis.
- You can use an engine as a player for a game.
Dark mode option

There is wide user handbook where you can see how the application works.

The translator of this handbook is Tamara Perry

Complement of ChessPdfBrowser application

Command line application that allows getting the games of a pdf chess book as .pgn

It accepts several parameters that allow:

To configure input file name (.pdf book)
To configure output file name (.pgn file)
To choose language of games in that pdf.
To select the range of pages over which the extraction will be done.

There are a pair of basic scripts for different environments that make java invocation passing the parameters to the application:

.bat script for windows
.sh script for unix type environments

TextCrypt is a small application developed in Java with which you can encrypt and decrypt plain texts.

Text is never stored in the hard disk, it is always stored encrypted.

The format of the encrypted file created with this application, is compatible with the one of the Java File Encoder application, simply by changing accordingly the extension.

Some errores were fixed in this version of the application.

Some new functionalities are added in this version of the application:

Functionality of undo/redo for text editions.
Functionality of copy/paste of text.
Functionality of search/replace including regular expressions.
Zoom factor for the windows of the application.
Detection of urls and e-mail addresses.

In this version we have tried to avoid an error produced by the interaction with a new functionality of Java-9 (which automatically deals with screens with a high density of pixels (dpi)).

As a novelty, support for Maven has been added.

This version of the application includes the new version query.

New dark mode option

Instrumental music is a small Java application which receives the data from the microphone and process the input signal in real time and detects the predominant music note.

You can try whistling and then configurethe application to play that same detected note using the MIDI device.

It's a simple entertainment tool.

With this version platform libraries version is upgraded:

You can change zoom level of application.
New version query (to have some statistics about how many people uses the application).
Dark mode option

Now you can also configure the threshold for detecting a note

This application version arises thanks to the extra free time got after the ban to enter bars and restaurants in Catalonia without COVID certificate during Christmass'2021.

The most remarkable novelty, is that it allows changing the voice pitch, to lower or sharper pitch, depending of a slider.

New classes that easy the creation of producers and consumers.
New classes that allow consumming audio packets, and to process them in the frequency domain, appliying a STFT.
Several improvements in the classes structure and to the User Interface.
jdk-17 compatibility

Demo video

This module includes the libraries that have common classes to all the applications that I have been programming.

Basically is divided into two sublibraries:

libGeneric
libGenericDesktop

libGeneric includes classes that do not depend on the environment, and that (theoretically) can be used in applications under any environment, Android included.

libGenericDesktop, includes classes that are more dependent on Swing (Desktop environment of standard Java). It includes:

Internationalization environment.
Base classes for JFrame and JDialog of the applications.

This module includes the libraries that have common classes to all the applications that I have been programming.

Compared with the previous version, it adds:

Base classes for License, About, Splash, etc. windows.
Suport for zoom of views (zoom little, medium, big).
Automatic support for undo/redo on text components.
Automatic support for copy/paste on text components.
Several other functionalities on visual desktop components.

This module includes the libraries that have common classes to all the applications that I have been programming.

Compared with the previous version, it adds:

Support for links on text components.
Several other functionalities on visual desktop components.

This module includes the libraries that have common classes to all the applications that I have been programming.

Compared with the previous version, it adds:

Disabling of the functionality of view scaling in systems with high density of pixels (dpi).
Improving of zoom of jcombobox.

This module includes the libraries that have common classes to all the applications that I have been programming.

Compared with the previous version, it adds:

What is new window.
New version query.
Dancing torus in About ... window
Common classes for start and initial load of configuration.
Common clases for autocompletion window.
Dark mode option

New 3rd-party libraries, which have been included for comodity of compilation, and libraries have been divided into two groups, depending on their license (gpl y gpl):

lgpl:
- 3rd-party:
  - libImageProcessing. Functions found on the internet for image processing.
  - libTableColumnAdjuster. Class found on the internet for adjusting the width of columns of a JTable.
  - libScreenImage. Class found on the internet to create an image of a visual component in a BufferedImage.
- own:
  - libGeneric. Library without dependencies that has many common functions that do not depend on classes of a particular view environment.
  - lib3Dapi. Library that contains the 3D interface that applications use (it allows not depending on a particular implementation of a 3D library).
  - libPdf. Library that contains the interface for dealing with Pdfs, without being attached to a particular Pdf library
  - libInetQuery. Library that contains the interface for connecting with backends, without depending on a particular implementation library.
  - libGenericDesktop. Librería que contiene muchas clases comunes asociadas a swing. (Paneles comunes, imágenes, componentes con zoom integrado, ventanas comunes a todas las aplicaciones con sus clases base, ...)
  - libGenericCommandLine. Library that contains many common classes associated to a command line environment. It is for an environment with the desktop classes of JDK-8.
gpl:
- 3rd-party:
  - java3d-utils-1.7.0-pre1. Fork library of the old java3d.
  - java3d-core-1.7.0-pre1. Fork library of the old java3d.
  - vecmath-1.7.0-pre1. Fork library of the old java3d.
- own:
  - lib3D. Library that implements the interface of lib3Dapi, and has java3d librar of gpl-3rd_party section (gpl) as requirement.
  - libPdfboxWrapper. Library that implements the interface of libPdf, and that has the usage of Pdfbox library (which had some old optional gpl requirements) as requirement.
  - libJerseyInetQuery. Library that implements the interface of libInetQuery, and that has the usage of Jersey library (gpl) as requirement.

Functionality of libraries:

Multi-language support
Zoom
Dark mode option
Automatic Undo-Redo for text components, with popup menu
Search and replace window prepared to be used.
Base Autocompletion window.
Relocation of visual components after a resizing of the window.
Base classes for text format on the fly in JTextPanes
Improved JFileChooser
Basic functions of all kinds:

Accurate image resizing
Image processing, translation of color of every pixed by providing a direct color translation function.
Classes to easy xml file management (without validation)
...

This tiny application allows you to create the icons for an application taking as input an image and resizing it to different Windows standard sizes:

16 x 16
32 x 32
64 x 64
128 x 128

You can also resize that input image to a configurable size that can be different from the previous ones.

When resizing, you can translate a particular color to another one (that can be useful to change the background, that might be transparent to white).

You can change the alpha component (of transparency) of the rest of pixels too

New dark mode option

With this application you can open Pdf books and inspect their images and text.

It is a basic example of what can be done using pdfbox library.

New dark mode option

That application shows a Donut in three dimensions, giving the possibility to apply rotations in both axis.

It is a basic example of what can be done using platform libraries.

Functionality of libraries:

Multi-language support
Zoom
Dark mode option
Automatic Undo-Redo for text components, with popup menu
Search and replace window prepared to be used.
Base Autocompletion window.
Relocation of visual components after a resizing of the window.
Base classes for text format on the fly in JTextPanes
Improved JFileChooser
Basic functions of all kinds:

Accurate image resizing
Image processing, translation of color of every pixed by providing a direct color translation function.
Classes to easy xml file management (without validation)
...

This application is a music player.

It works with play lists of type .m3u, which can be created by dragging and dropping music files from the file explorer.

Supported formats:

5 band equalizer (from 0 dB to -20 dB)
5 band graphical equalizer
Random mode option.
Continuous play option.
Option to stop automatically the play after the end of the current song.
Song navigator

Demo video

The idea for this application has been in my mind for some time.

Ever since I was young, I've been fond of programming, and liked to watch the demos that many teams of computer programmers hosted for different demo competitions around the world.

I was impressed by many of the demos, considering the capacities of computers at that time.

Once, I saw a demo of a Spanish team that used a morphing effect: the members of the team morphed from one to another, and lastly into an iguana (this was fitting, as the team’s name was Iguana).

It was an effect that caught my attention.

Over the years I have been thinking about how to achieve this effect, and finally have figured out a way to do so. Now, as the final product of my efforts, I am pleased to present you with this application. I have also compiled a user guide that explains how the application works step-by-step.

There is a handbook that explains how to use the application.

Demo video

Video created with the application