QtAV1.dll can not be found

[javlada]

Hi,

I'm developing a cross platform Qt/QML music (with video support in future) player. It can be found here, if anyone's interested.

Currently I use QtMultimedia but I'm looking for a better solution and QtAV seems to be the perfect match. Today I did the first steps. I successfully built and installed the Android version then downloaded and installed also the Windows version.

I was able to build and execute the example from this wiki article for Windows and Android.

Then I wanted to try the C++ part and here my problems started. I wanted to examine the audiopipeline and simpleplayer examples. But I can not build them. I get this error when trying to build them. mingw32-make[1]: *** No rule to make target 'C:/QtProjects/QtAV/examples/build-simpleplayer-Desktop_Qt_5_6_1_MinGW_32bit2-Release/../out/lib_win_/QtAV1.dll', needed by '..\out\bin\simpleplayer.exe'. Stop.

The file is located in %QTDIR% (_c:\Qt\5.6\mingw4932\bin\), so it should be available. What am I doing wrong? I really don't have much understanding how linking of shared libraries works. I'm in the process of learning C++ and I use my player project for it.

Also I would like to get an advice regarding the best solution for my application. I would like to implement following features not available in QtMultimedia:

• gape-less playback
• correct replaygain support (increase volume above 100% of original)
• spectrum analyzer (through fft analysis of raw audio data)

Can this be done using QtAV? If yes, what should be the best approach? Is there an API reference?

Thank you very much!

--- Want to back this issue? **[Post a bounty on it!](https://www.bountysource.com/issues/37304730-qtav1-dll-can-not-be-found?utm_campaign=plugin&utm_content=tracker%2F307703&utm_medium=issues&utm_source=github)** We accept bounties via [Bountysource](https://www.bountysource.com/?utm_campaign=plugin&utm_content=tracker%2F307703&utm_medium=issues&utm_source=github).

[wang-bin]

Build QtAV and run sdk_install.bat in build dir. Then open examples/simpleplayer/simpleplayer_sdk.pro to build against installed QtAV module.

• gapless: you can use 2 players, preload the next player when playing the current one.
• replaygain: not supported yet
• spectrum: no. But you can use AudioFilter

[javlada]

Thank you. I have no idea why but it suddenly started to work. Maybe windows needed restart for some reason. Anyway I successfully replaced QtMultimedia by QtAV in my project and everything works great.

• Thank you for the tip regarding using 2 players to get gapless playback. That could do the trick. I will need to read the data for gapless playback and make sure the timing will be correct. Using a playlist would not work?
• I implemented the replaygain support myself. I just needed to be able to set volume above 100% which is possible with QtAV.
• Regarding the spectrum analyzer, I would write it myself. But I need to have access to the decoded data. Is it possible? What is AudioFilter and how do I use it? I searched for it in example's code but I didn't find anything that would help me.

Thank you for your help and the work on this great library.