Dear all,
As part of the ongoing lavtools project (mjpeg.sourceforge.net) I have
given the MSSG encoder "mpeg2enc" and some related tools a thorough
overhaul.
An initial beta (based on older stable versions of the mjpeg-related
components) is now ready.
Key improvements are a reasonably sophisticated motion compensation
search algorithm, better bit-allocation/quantisation, plus MMX/SSE for
key compute intensive routines.
Its now in daily use compressing mjpeg .avi and .mov captured using a
Buz to MPEG-1 VCD for playback on hardware and software players and
ready for testing away from home ;-) It should work with mjpeg
.avi's and .mov's from other sources.
Summary of release notes follow...
Andrew
THE HIGHLIGHTS
On MMX / SSE CPU's around 10 times as fast (probably rather more) than
the original mpeg2enc and gives *better* results too.
Its in daily use for compressing captured video to VCD format MPEG-1
and the results (played through software and a DXR2) have satisfied
the author and friends and relations. On good quality sources they're
*noticeably* better than PAL VHS.
Compression is around 6 frames/sec on a Celeron 366 with somewhat
better quality results than the original at identical motion
compensation search radii. Results are *much* better quality than the
acceptably-fast limted motion-compensation compression using the
original.
LIMITATIONS
I (as@comlab) have no convenient way of checking MPEG-2 streams so all
the mpeg2 support is unchanged over the (far from ideal) support
offered in the original mpeg2enc except that the new motion
compensation and quantization / bit allocation may be quite badly
tuned and/or buggy
on MPEG-2.
I'd be very keen to hear from anyone's experiences trying MPEG-2. I
think mplex won't handle it but video alone may work o.k....
It is just possible NTSC might have problems. I live in Europe...
This situation will improve in a final release (see README).
Don't even *think* abot VBR encoding. The support in mpeg2enc is very
limited and mplex will make a complete hash of multiplexing it. This
situation will change *soon* in the next beta iteration (see README).
Many thanks go Brent Byeler working on bbmpeg for Windows from whom I
pinched several of the MMX routines.
Andrew
