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Conference hydra::amiga_v1

Title:AMIGA NOTES
Notice:Join us in the *NEW* conference - HYDRA::AMIGA_V2
Moderator:HYDRA::MOORE
Created:Sat Apr 26 1986
Last Modified:Wed Feb 05 1992
Last Successful Update:Fri Jun 06 1997
Number of topics:5378
Total number of notes:38326

4671.0. "Looking for Multi-Media Guidance" by NEMAIL::MILLERC () Tue Apr 09 1991 15:47

Hello, a friend of mine entered the following note in the Multi-Media Notes
    Conference.  It sounded like something that an Amiga Multi-Media expert
    would find an easy thing to explain.
    
    Can any of you folks explain how this is done in generic terms, so she
    can seek the appropriate resources to accomplish this task in the DEC
    RISC space.
    
    Shelly will be monitoring the Amiga Notes Conference, so please direct
    your comments/responses directly to her.
    
    Thanks,
    Chuck
    
             <<< LPSTCK::USER1:[NOTES$LIBRARY]MULTI_MEDIA.NOTE;1 >>>
                                -< Multi-Media >-
================================================================================
Note 43.0                     real time audio/video                    9 replies
POBOX::SEILER                                         4 lines  26-MAR-1991 17:03
--------------------------------------------------------------------------------
    Please help. I have a customer who would like to record pieces of
    movies from a vcr onto Optical Disk and display it on a workstation with 
    audio real-time. (I'm not really sure if I'm explaining this correctly)
    How can this be done?

    Shelly
================================================================================

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4671.1A stabBOLTON::PLOUFFAhhh... cider!Tue Apr 09 1991 18:1245
    I'll be foolhardy and take the first stab.  The Amiga has a hardware
    advantage that will add significant cost to a workstation solution:
    NTSC compatibility (PAL in 50 Hz countries).  Any workstation solution
    will have to either add hardware capable of displaying a standard video
    signal as a window on the workstation screen, or else record and play
    back at workstation resolution.
    
    Now, let's take the original posting bit by bit.  Every Amiga sold in a
    U.S. computer store these days comes with multimedia authoring software
    called AmigaVision.  AmigaVision contains an iconic scripting system
    which coordinates presentation of video (through a genlock), animation,
    sound and still graphics.  It also contains device drivers for several
    brands of videodisc players.
    
    Since videodisc is frame-addressable, it is straightforward to build an
    application containing still frames and action sequences from the
    videodisc.  As yet there is no "Editor's Workbench" or other
    productivity tool to help create these applications.  However, MIT has
    been doing work along these lines for its non-Amiga systems in the
    Media Lab.
    
    AmigaVision can coordinate audio and video playback but is limited by
    memory and processor power as to the length of sound sequences.
    
    Recording a videodisc is beyond the scope of this note.
    
    Another possibility is a write-once optical drive.  Here video
    sequences taken from a video capture card can be recorded as files, and
    AmigaVision can play back file-structured sequences, as opposed to
    frame-structured sequences.  The program is smart enough to cache data
    ahead of use, and some animation players allow long animations to be
    played from hard disk.  I/O bandwidth is an issue: typical Amiga SCSI
    interfaces are capable of 300-800 KBytes/sec read rates, slower write
    rates.  This may be too slow for real-time video frame capture, but
    sufficient for playback.
    
    The original note in MULTI-MEDIA mentioned CD-ROM.  From the note on
    CDTV, it appears that CD-ROM is far too slow to play back real-time
    video with only software compression.
    
    So, the key pieces are, IMO:  broadcast video display compatibility,
    authoring tools, I/O bandwidth and a way to capture video to fixed
    media.
    
    Wes
4671.2Amiga-NO MAC-MaybeHYSTER::DEARBORNTrouvez MieuxWed Apr 10 1991 11:2821
The AVID System, which runs on a MAC II allows you to record video directly to 
hard disk for instantaneous playback of any portion.

AVID is a full featured video off-line editing system.  It uses large banks of 
hard drives to hold all the digitized video.  Playback resolution of the video 
is not the same as you see on TV, through compression, the images are probably 
about 200X200.

In order to play back or record broadcast quality images from memory or disk 
(not VIDEO disk or CD) you need a massive amount of disk space and tons of 
memory.  Brief sequences (less than 10 seconds) are easier to do.  Anything 
longer...good luck.

Now, if you are just playing back images from a videodisk or CD device, that 
is another matter altogether.  

Medialab at MIT is an excellent source for information on this subject.  They 
have been doing a lot of research in this area for the last few years.

Randy