True, but when you cut from one source to another the ENTIRE picture changes, resetting the conditions for "b" and "p" frames also.Dave Loudin wrote:Ture, but wouldn't dropped I-frames lead to stuttering of the entire picture? What lostone describes, now that I think about it some more, is classic bit-starving. The video noise is the slow filling-in of resolution via the p and B frames. Streaks maybe are decoder hits. I see the same thing on WETA-DT, as they run PBS HD plus THREE SD subchannels. Static pictures look great. Everything else is crap.genlock wrote:The break-up at the transition point is because of the transmission if "I" frames.
Full picture, lots more data.
At other times the entire picture does not change much so "p" and "B" frames are sent.
Only the changing parts of the picture. Data load can sometimes be quite small.
You will get very important "I" frames and if they are missing or compromised, the MPEG-2 conditions are lost. Breakup or loss of picture.



