simple javafx application to convert an mp4 file into mp3 - javafx

I want to write a basic application that converts an mp4 file into an mp3 file using javafx, but I don't know the API's necessary to do so - if there are any.
Can you please assist me with code snippets?

You could use ffmpeg and a JavaFX gui.
But since it's "basic" as you say, you may as well use a batch command for it.

Related

Opening/Editing Qt Resource File (.rcc)

I want to translate a program; but its language files (.qm) are in a .rcc file.
The program is not mine, so I haven't got any .qrc file.
Before asking this question, I have searched this site about this issue; but I don't attain anything.
Is there any way to extract/decompile it?
You can take my tool RccExtended - it based on the official Qt resource compiler with additional function to decompile binary resources.
Usage example:
cd \Path\To\MyQtResources\
rcc --reverse
Decompiler will unpack all .rcc files in the current directory, generate .qrc files and make.bat file to compile resources back to the binary format.
There isn't a supported way to decompile it as far as I'm aware, but it's a binary file format that can be read and handled. There's a nodejs example of how to read the file and extract PNGs on github: https://github.com/gcochard/png-extractor. It may be possible to extend that method out for the .qm files.
However there's other issues with attempting to add more translations to a Qt application without having the code, depending on the language you're attempting to add, how the developer has exposed the other languages etc.

Encrypting and decrypting android expansion file

I have successfully uploaded and published my android app + apk expansion file (with format .obb but is actually a .zip) on Google Play. I would like to set up some protection to it. Are there any ways to do it to acheieve this without using external jar classes like zip4j?
In my obb file I have a few videos (of .mp4) that I need to use my mediaplayer to read it. I want to do this so that only my media player can read the obb file.
Thanks.

Creating Documentation Using QtHelp Module

Qt provides two kinds of help files: Qt Compressed Help (.qch) and Qt Help Collection (.qhc).
The first one actually contains compressed help data (html pages, images etc). The second one contains references to different compressed help files.
Both Qt Assistant and QHelpEngine are using collection files to display help. So I need at least two files to provide documentation for my application: .qch and .qhc.
I want to have a single help file to be used by Qt Help API (e.g. like a .chm help file in Windows).
Is it possible?
I don't think it is possible to create a chm file using QtHelp module since chm files are Microsoft specific and not an independent format.
But all the chm files are opened by the hh.exe application that belongs to HTML Help workshop. I have accessed chm files for opening a specified html page using hh application.
You can have a look over here in my answer.
If there are command line options provided by Microsoft to compile chm files either by hh or through HTML Help workshop command line (if any), you can do that by running the command in QProcess. You have to probe more into that.
Or you can create chm files manually using HTML Help workshop and integrate the chm files into the application.
Hope that helps in giving you a start.
I have not tried this but have a look at chm2qch, Tool for converting Windows CHM files to Qt Help format.

Library to compress a file as a.qzip

I have some files whose extension is qzip, for example a.qzip.
It seems that those files are compressed with a library of qt.
Could anyone tell me what it is?
Thankyou very much.
According to this FAQ page:
Qt uses the zlib library to provide compression. This means that you can compress and decompress your bytearrays of data using Qt. [...]
Note that this does not produce file archives that can be opened by other applications, to do that you will need to write it yourself using Qt’s custom file handling system or use a 3rd party library.
Which if someone (lazily) created a file using qCompress() you would need to write your own code to read the file as a QByteArray then use the corresponding qUncompress() method to read it. There is no official qzip format related to Qt that I know, so you should probably go and slap the developer who made these files if it works out!
In general, if you want to compress data that will be reusable, use a common file format.
This was the only reference I have found on the entire www over qzip.
quicklz

How to link to a PDF file in Qt Assistant?

I use Qt Assistant as a help viewer and I have an internal link to a PDF file that is embedded into the compiled archive format. When I click on that link, nothing happens. How can I link to a PDF file that is embedded, click on the link and have an external application opened? I use Qt Assistant 4.7.3.
Short of bundling a program like Okular into your application release and launching it as an external process there isn't a native way of arriving at your solution. More options are discussed here as well, to sum it up it's either externally or converting the PDF to a QPixmap.
I don't think that this can work. To display a pdf file you need Acrobat or a similar (external) program, and this program needs a file to read. Why don't you store the pdf files outside the help file?

Resources