Qt ffmpeg wrapper example not working out of the box (solved)

SGaist

Hi and welcome to devnet,

AFAIR you need to install the development package of ffmpeg, it's really just a wrapper.

jimhi

Ok, I did apt-get install ffmpeg, but it still has the same error

SGaist

That's normal, you just installed ffmpeg, not the development package

jimhi

Thanks!

apt-get install libavutil-dev libavformat-dev libswscale-dev libavcodec-dev

did the trick for those errors, now I have about 71 errors involving the function calls to those libraries.

output:
undefined reference to 'avcodec_init'
undefined reference to 'avformat_version'
etc..
etc

What's going on here?

SGaist

Wild guess: the wrapper was written for an old version of ffmpeg. You'll have to update the code a bit

jimhi

(to anyone else watching in the future) I changed all

uint_8 to ffmpeg::uint_8

so it will recognize their types

jimhi

Downloading the latest build of qt ffmpeg wrapper fixed all the errors, but left about 70 warnings about deprecated functions and comparing unsigned and signed ints. After fixing all those, there are no errors left and QT builds and exits without any problems.

However, I can't find a file to run after building. The example is called simpleencdec and I can't run

./simpleencdec

in the build directory. Any suggestions?

SGaist

Did you open and build the example project ?

jimhi

Yes, as I said, I built the project and it had 0 errors and warnings. (ctrl + B)

On a second look, I do get one strange error when I build the project

Project MESSAGE: Warning: unknown QT: widgets

jimhi

I have fixed it.

I have been running it from my SD Card which was causing problems. When I moved it onto my raspberry pi, it created the file properly. I Chmod 777 the sd card, but it still didn't work.

Thanks for everything

SGaist

If you are building with Qt 4 you don't have the widgets module

You're welcome !