When a web server returns a JPEG image (mime type image/jpeg), how is that encoded?

Question

If you make an HTTP request to a web server, and it returns a response of type image/jpeg, how is the binary data actually encoded? Is it the original byte-level content of

Answer 1

The original bytes are sent across the wire.

(With a bit of setup, you can confirm this with Wireshark, tcp_dump et al.)

Note that most servers are configured not to compress JPEGs, but that text data is generally sent compressed.