What role does a codec play in audio and video transmission?

A codec is essential in audio and video transmission as it serves the purpose of compressing and decompressing audio and video data. Compression is vital because it reduces the file size, which facilitates faster transmission over networks and more efficient storage. By minimizing the amount of data being sent, a codec allows for smoother playback and transmission, particularly important in streaming services where bandwidth can be a limiting factor.

When transmitting audio and video, large file sizes can lead to delays and buffering issues. A codec not only makes it possible to transmit high-quality audio and video efficiently but also allows for the different formats that are commonly needed for various platforms and devices. By decompressing the data at the receiving end, the codec ensures that the media can be played back in its intended quality.

In contrast, other options focus on different functions: adjusting audio levels pertains to mixing rather than coding, converting analog signals to digital formats is a different process sometimes handled by DA converters, and enhancing video resolution and frame rates relates to image processing rather than the fundamental data encoding process.