lite kommentarer från apples dvd lista:
"even though the MPEG2 component will allow you to decode,
it does not infer that it will create editability of a codec
that is, essentially, uneditable except on GOP boundaries.
I think the right solution for this is to remember that
MPEG2 is a DESTINATION CODEC, and not designed to be
editbale on frame boundaries. The ONLY exception to this
that I have seen is when Fast and Pinnacle have provided
I-frame only encoding (or some pseudo-variation on this)
that allows editing on the I-frame boundaries,
BEFORE the file is compressed down into its traditional
I-P-B MPEG2 format. I-P-B is quite uneditable, for
obvious reasons Only the I-frame contains all of the pixels!
sorry to get technical, but that´s the easiest way to explain
this.
"
"There are plenty of codecs that QT will let you edit with which contain p & b frames. Apple has just chosen not to implement this functionality with mpeg 2, and rightfully so, imo. It´s a waste of their engineering time, imo.
I do agree that mpeg 2 should only really be considered a destination codec (unless being used on a specific system designed as an mpeg 2 editor, which is usually i-frame-only based and you´d still have to re-encode before final delivery...).
"
