I have two doubts…
Suppose there is already some video on youtube and we download that videos in your computer. Then after, We edit them, add logo and make other changes… So after doing all this… Will that videos eligibe for monetization?
Second question: Some people using to upload popular videos like doraemon, cartoon network etc… without monetizing to get Subscribers and then after they upload their originally developed video on the same channel and monetize the video… now the subscribers will send large views on the video with earnings… Is it ethical?
You can’t use other people’s content without permission - it’s theft. I doesn’t matter if it’s an article, an image or a video; they retain copyright. And contrary to popular belief, altering the content in some way, or “spinning” an article, does not make it legal.
Also Youtube is very good as spotting copyright issues. It analyses the uploads, both visual and audio to detect similarities to existing copyrighted material.
In fact it is so good at this that you can even get some organisations making spurious copyright claims against you for material that they don’t even own. Yes, I’ve had this, but you can appeal and they do go away if you challenge them.
If you do upload copyrigthed material to Youtube, the best case is that the real owner monetizes your views but the content remains. In the middle, you may get it removed or yourself banned. At worst, you could end up in court.