A video source device generates a session key for each transmission session wherein a multi-frame video content is to be transmitted to a video sink device. The video source device uses the session key to generate a successive number of frame keys. The frame keys in turn are used to generate corresponding pseudo random bit sequences for ciphering the corresponding frames to protect the video content from unauthorized copying during transmission. The video sink device practices a complementary approach to decipher the received video content. In one embodiment, both devices are each provided with an integrated block/stream cipher to practice the transmission protection method.