The entire purpose of compression is to remove redundant information. As
David implements temporal delta coding and in general improves the
codec, the cost (in reduction of speech quality) of losing a bit increases.
It seems to me that the most critical packets will be key frames, those
which have a complete set of LSP information. Within them we have some
differences in the cost of losing a bit.
Between those are delta frames. If the deltas are relative to other
delta frames, losing one of those bits potentially corrupts all of the
succeeding deltas until a key frame. If the deltas are only relative to
the key frame, we lose less data, but the delta frames must then handle
a larger magnitude and compression might be worse.
What can we do to reduce the magnitude of a single-bit error before we
apply FEC? I put in Gray coding a while back, but this was more
guesswork than theory.
Thanks
Bruce Perens
The Philosopher's Song (Monty Python)
Immanuel Kant was a real pissant
Who was very rarely stable.
Heidegger, Heidegger was a boozy beggar
Who could think you under the table.
David Hume could out-consume Wilhelm Freidrich Hegel,
And Wittgenstein was a beery swine
Who was just as schloshed as Schlegel.
There's nothing Nietzsche couldn't teach ya
'Bout the raising of the wrist.
SOCRATES, HIMSELF, WAS PERMANENTLY PISSED...
John Stuart Mill, of his own free will,
On half a pint of shandy was particularly ill.
Plato, they say, could stick it away;
Half a crate of whiskey every day.
Aristotle, Aristotle was a bugger for the bottle,
Hobbes was fond of his dram,
And Rene Descartes was a drunken fart: "I drink, therefore I am"
Yes, Socrates, himself, is particularly missed;
A lovely little thinker but a bugger when he's pissed!
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