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- From: hurh@fnal.fnal.gov (Patrick Hurh)
- Subject: Re: How to get a 5 second 'burst' of real-time animation on a Mac
- Message-ID: <hurh-250193122613@phurh.fnal.gov>
- Followup-To: comp.sys.mac.hardware,comp.sys.mac.misc,comp.graphics.animation
- Sender: daemon@linac.fnal.gov (The Background Man)
- Nntp-Posting-Host: phurh.fnal.gov
- Organization: fnal
- References: <1993Jan18.184147.10292@njitgw.njit.edu> <1993Jan24.202451.5700@netcom.com>
- Distribution: usa
- Date: Mon, 25 Jan 1993 18:28:23 GMT
- Lines: 36
-
- In article <1993Jan24.202451.5700@netcom.com>, ray@netcom.com (Ray Fischer)
- wrote:
- >
- > meg5184@hertz.njit.edu (Starman) writes ...
- > >I was wondering if it's possible to get a 640x480 (or smaller for
- > >overscan) image to play in real time on a Mac for a period of no more
- > >than 5 seconds. I have a Mac IIcx with a RasterOps 364 board and I need
- > >to dump animations to tape. I have other, but more complicated means of
- > >doing videotapes, but since the animations won't be long, I was
- > >thinking that there might be a way to get a 640x480 24 bit color
- > >Quicktime movie to play at 30fps. I would assume I'd need some sort of
- > >graphics accelerator. Can anyone tell me of the right thing to do?
- >
- > Not possible.
- >
- > Let's look at some math. But first, note that NTSC is only 640x200
- > interlaced. The extra vertical resolution can't be used.
- >
- > Math: 640 * 200 * 3 (bytes) is 384000 bytes. Times 30 (frames per
- > second) is 11520000 (say 11MB). Thus, you're asking if a 16MHz 68030
- > can transfer 11MB per second from memory across NuBus to a video board
- > in one second. If it's 640x480, then the number is 27MB.
- >
- > I don't think so. Sorry.
- >
- > --
- > Ray Fischer "Convictions are more dangerous enemies of truth
- > ray@netcom.com than lies." -- Friedrich Nietszsche
-
- I'm a newbie at this stuff so please forgive... Is the limitation the
- NuBus? What is the throughput of a Nubus? If the animation is stored in
- fast RAM disk what is the max frames/sec which can be transferred to a
- video card? Barring all these stupid questions...what is the preferred
- method of output to video (is it just not full screen?)?
-
- Thanks in advance, Patrick
-