What is one of the main applications for stream ciphers like Mickey v2?

Stream ciphers like Mickey v2 are particularly well-suited for real-time video encryption due to their ability to process data in a continuous, streaming format rather than in fixed-size blocks. This characteristic allows them to encrypt data as it is being transmitted, making them ideal for applications that require low latency and high speed, such as live video feeds. Stream ciphers are efficient in handling data streams, enabling timely encryption and decryption without introducing significant delays.

In contrast, other applications mentioned may not align with the primary strengths of stream ciphers. For instance, email encryption typically involves larger, discrete message formats that are handled more effectively by block ciphers. Large database encryption tends to prioritize strong security measures that might be better suited to block-oriented approaches. File compression, while important in data management, does not directly relate to the encryption capabilities and real-time needs that stream ciphers address. Stream ciphers excel in environments where speed and efficiency in handling continuous data streams are critical, making real-time video encryption their standout application.