All perfect praise be to Allah, The Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad is His slave and Messenger.
What was shown in that video is a great evil, and it is not permissible to see it nor to stay in the place where the video is played; Allah says (what means): {And it has already come down to you in the Book that when you hear the verses of Allah [recited], they are denied [by them] and ridiculed; so do not sit with them until they enter into another conversation. Indeed, you would then be like them. Indeed Allah will gather the hypocrites and disbelievers in Hell all together.} [Quran 4:140]
You should have left the classroom if you did not fear that you would be harmed by doing so.
However, a Muslim does not become a disbeliever just by seeing that film; the saying of Allah in the previous verse, ‘you would then be like them’, does not entail committing disbelief; rather, it means sharing the sin.
Ibn ‘Aashoor said in At-Tahreer wat-Tanweer, “This similarity indicates considering this sin as very grave, as a threat and to frighten (people from doing it). A believer does not become a hypocrite by sitting with the hypocrites; the similarity is in regard to the sin, and not to the extent of the sin; that is to say that you would be like them in being involved in sins.”
Finally, we would like to point out the seriousness of studying in such universities, and that a Muslim should endeavor his best in looking for another university that does not involve such violations of Islam.
Allah knows best.