Craig Birkmaier wrote: >It is time to let go of interlace, 59.94, and maybe even 50P. A more >logical heirarchy for the future would be: >24P for film >36P for talking head and low motion video >60 and/or 72P for rapid motion. Regarding the choice of a universal frame rate, considering some papers by Mark Shubin and some considerations of John Watkinson on the need for really high frame rate for realistic motion rendition and the efficiency of compression for the highly correlated/redundant input material that such rates would produces, it would seem natural to settle on 300 Hz, which is no longer unrealistic with the current state of technical affairs. This achieves compatibility with both 50 Hz and 60 Hz legacy material by simple frame duplication. It brings on the table the superior compatibility with films of 50-multiple standards ("PAL speed up"), in preference to the motion-crippling 3:2 pulldown workaround, though in principle both could still be used. There is still the possibility of using motion compensation for those who accept neither of those compromises. At the beginning, one could still use either 50P or 60P cameras and duplicate frames. So one could shoot in every country at the correct rate to avoid beating with the mains frequency. On LCD (non pulsed) displays, the repeated frames would simply merge into a single one with a longer display time, essentially recreating the original captures rate. Because of the redundancy of duplicated frames, compressed bit rate would indeed not be much higher than the current one, or equal if we simply transmit 50 or 60P and let the receiver to the duplication. Once the standard is deployed, with the improvement in camera technology, it will be possible to capture at 75 fps, then 150 fps, then finally the full 300 fps and still retain full compatibility in the process (though one should be prepared to allocate more bandwidth when that happens, unless compression technology has advanced to the point where it can absorb the difference). This slightly favours the 50 Hz world when it comes to shooting in artificial light, as it would operate correcly at 50, 150 and 300 fps, while 60 Hz lighting could only use 60 and 300. But 50 Hz is what most countries of the world use, so by virtue of numbers, it should be given priority. Also it is more universal, being more film friendly, while 60 Hz is essentially only compatible with itself. Even if we don't fully use the 300 Hz capability initially, it will still be very useful as a unifying standard. It would require little or no initial upgrade of transmission facilities to achieve this, what it needs is a 300 Hz capable display, which the manufacturers seem to already provide. In the case of external set top boxes receivers, though, what would be missing would be a standard to transmit uncompressed 300 fps from the box to the display (about 7.5 Gbps in 4:2:0, 8 bits, 2D, within capability of HDMI 1.3 hardware). This is less of a problem if the receiver is integrated into the display. ---------------------------------------------------------------------- You can UNSUBSCRIBE from the OpenDTV list in two ways: - Using the UNSUBSCRIBE command in your user configuration settings at FreeLists.org - By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word unsubscribe in the subject line.