The violation is depended upon the contract between Youtube and the Producer of the song under whose authority the song is published on Youtube.
All the material available on Youtube is covered and protected under the copyrights law of India. The content available on Youtube cannot be downloaded without the permission of the website which is given on the basis of the copyright protection of each material. For, example the producer of a video can allow therelease of his video but can create a condition that the video will cannot be downloaded as per which Youtube cannot allow another person to do that. With regard to this it is not necessary that the original work must be registered somewhere as registration is optional however is a strong prima facie indicator of the copyright. Therefore to determine if there is a violation it is necessary that the contract between the producer of the video and Youtube must be examined to throw more light on the copyright violation.
However, a simple plagiarism is not a copyright violation as a violation requires that there must be fundamental and material similarities between the works. In cases where a similar idea is developed in different manner, similarities will occur, it then the duty of the court to look into whether the similarities are fundamental or substantial by going through the work.
In the present case, firstly it must be seen whether the video edited was copyrighted. In all probability the video released on Youtube will vest the copyright with the producer. The examination of the contract is required to ascertain whether the producer allows such a form of use of this video or not. If the contract provides that the video cannot be used in any other way or for any other purpose other than as a part of the movie without the permission of the producer then the example cited in the question is a form of copyright violation. Where there is anyform of coyright violation Youtube can pull it down the infringing material on requests of the Producer.
Berne convenction and Universal Copyright convention.
Know your copyright, G.D Ghosla, P.11
Hindustan Pencils Ltd v Alpna Cottage Industries the Copyright Board of Goa
R.G. Anand v M/S Delux Films