Question: In a 3GPP-compliant video telephony setup, what is the primary purpose of transcoding circuitry or software in relation to video I/O equipment?
Option 1: To enhance video quality by applying additional compression algorithms
Option 2: To facilitate encryption for secure video transmission
Option 3: To convert between the standard format of the video signal/bit stream from I/O equipment and the format mandated by the video codec
Option 4: To adjust the frame rate for better compatibility with various display monitors
Explanation: In a video telephony setup, transcoding is crucial for ensuring compatibility between the input/output (I/O) equipment's video signal or bit stream format and the specific format required by the video codec. This conversion enables seamless communication and proper rendering of the video feed, highlighting the importance of format interoperability in telecom networks.