Miglia Technology AlchemyTV DVR User Manual
Page 53
I.
QuiickTime Codecs
AlchemyTV DVR relies on QuickTime to perform the encoding of your video footage. All codecs that
are accessible in QuickTime are accessible in AlchemyTV (export codecs are not included).
Some codecs should not be used with AlchemyTV, as they have been designed for other types of
applications, but many are useable.
The recommended codecs for capture with the AlchemyTV are Motion-JPEG and MPEG-4.
Motion JPEG: This codec has some fairly large space requirements, but has the advantage of
requiring less processing power to encode (eg. record) and remains editable in some
video applications. You can for example open a MJPEG video in Final Cut. You can
also do some basic editing (cut the adverts out of your recorded programme, for
example) with QuickTime Pro. There is no difference of any major consequence
between the two versions of MJPEG with regards to their use with AlchemyTV
DVR.
MPEG-4:
The MPEG-4 codec requires more processing power, but requires less hard drive
space to be recorded. Editing with MPEG-4 files is limited to cutting sequences.
MPEG-4 has a quality setting that will greatly influence the size of the resulting
video. It is recommended that you reduce the screen size to save additional drive
space.
DV-NTSC
DV-PAL:
DV-25 is the codec used by most Digital Cameras. AlchemyTV DVR does not feature
any DV-hardware encoder and may provide mixed results. This format is directly
readable by iMovie using the import function.
Cinepak:
Cinepak was the ‘native’ standard compression codec of QuickTime until release
3.0. Although fairly fast at encoding, it produces lower quality files with a
rather large size.
None:
No compression will be applied. This creates extremely large files.
You can attempt to use other codecs, but this might result in dropped frames or the inability to
record video at all.
Third party codecs include DivX and 3ivX, which are quite similar to MPEG-4.
DivX:
You can download a DivX codec installer from http://www.divx.com. DivX requires
an extremely fast processor (G4//1.25 GHz) to get good results with a half screen
size. The files will be very compact without affecting the quality. Full screen
recording is not possible even on a Dual 2GHz G5 (unless you have no
minimum expectations in terms of quality!)
It is essential to create a profile in the advanced settings of the DivX codec to
perform successful recordings.
3ivX:
You can download a 3ivX codec installer from http://www.3ivx.com. A Mac version
is also available. This codec uses less processing power than DivX and creates small
file size too. Full screen recording is an issue even on the fastest G5 processor.
The use of third-party codecs is not yet supported by Miglia Technology !
AlchemyTV DVR™ User Guide
Page 51