问题
I'm using LibVLC to display video files. It's working fine so far, despite of the orientation. I'm able to get the orientation out of meta-data but don't really know how to force LibVLC to rotate it from landscape to portrait.
It would be nice to get a hint for a workaround.
Thanks!
回答1:
I had a similar problem. Unfortunately LibVLC for android does not expose all features, so I had to change code in the jni layer to get it working. Here is how to do it:
Edit libvlcjni.c, and find the function : Java_org_videolan_libvlc_LibVLC_nativeInit. Look for the local varibale argv array and add the following to items to it:
"--video-filter=transform" "--transform-type="
Where transform type is one of the following: 90, 180, 270, hfilp, vfilp.
If you omit --transform-type you'l get a 90 degree rotation by default.
What this modifications does, is it loads the transform filter and then sets the transformation. You can do more fine grained rotation using --rotation-angle, but you'll have to load the appropriate filter first.
Hope this helps.
来源：https://stackoverflow.com/questions/23672155/video-rotation-on-android-using-libvlc