I suspect that the processing time is dependent on the transmission codec (for example h.264 HD is more resource intensive than MPEG2 HD), the resolution, and bit-rate.
HD channels use h.264 codec (although in some regional areas some HD uses MEPG2). Most SD channels use MPEG 2 - notable exceptions include 7Flix (Melbourne and probably elsewhere) and racing.com. The bitrate used on a particular (logical) channel is not fixed and can change from on program to the next.
HD channels use h.264 codec (although in some regional areas some HD uses MEPG2). Most SD channels use MPEG 2 - notable exceptions include 7Flix (Melbourne and probably elsewhere) and racing.com. The bitrate used on a particular (logical) channel is not fixed and can change from on program to the next.