Digital Video Compression  

 More information in [ Digital Video Design ]

History

Digital Technology has already revolutionized the way we live and do business. In the home, digital audio has become widespread since the advent of CDs over a decade ago, but digital video was not yet here !. Now the recent arrival of world wide standards and key technology components promise to uscher in a new level of high quality digital video.

The Problem

Video information stream is so large that even the recent new high speed technology cannot handle it without compression. According to the Standards (CCIR 601) the total information of a video stream is equivalent to a data rate larger than 166 Mb/s . At this rate, a 9 Gb hard drive would fill up in few minutes. The actual channels of distribution ( even the fastest available) require that to send or to store video, due to the large size of data, it must be compressed in real time from a minimum factor of 4:1 to an upper factor 250:1 This allow 2 to 3 hours of storage time on a 4 GB hard disk . To allow suck large compression a high quality, dedicated hardware and software are required. There are two basic method to do this compression: Jpeg and Mpeg. Jpeg is a compression system that has become a "de facto" standard. Unfortunately, each individual company's version is a different flavor so there is no possibility of interoperability. Mpeg is the industry standard compression algorhythm that has the best ratio between data size and quality and is much more efficient in compression than jpeg, so data storage requirement are far less. Mpeg itself has two different levels of compressin: Mpeg 1 and Mpeg 2. the following figure gives an idea of the ratio between the quality and the data size required: Some of Colby Systems products are available using all three types of compression. Each particular application and budget will determine which standard is the best choice.

   


DR - 3000The first portable Mpeg-1Digital Video recorder trasmitter

Video specifications

  • Winner of the the 1994 NAB "Mario" award for top then products ot the year.
  • The Colby Dr 3000 is the first Portable Digital Video Recorder using Meg-1 compression for the direct-to-disk recording and playback.
  • News gathering companies can take advantage of this device
  • Weight is 17 pounds and is housed in a briefcase that can be carry-on-luggage on an airplane.
  • Easily operated by means of a Smart Touch ™ LCD touch screen control panel featuring a simple VCR-like "record", "play" and "pause" buttons.
  • Recording is accomplished using Mpeg-1 compression Techniques , direct-to-disk on hard drive modules with capacities of 2.1 Gb to 9.09 Gb.
  • Video is viewed on a built-in 6" active matrix LCD color monitor.
  • Front Panel Video (Bnc) and Audio (XLR) connectors
  • The recorded material is the sent over 1 to 4 simultaneous analog phone, cell phone lines, ISDN or INMARSAT Satellite in non-real time from anywhere on earth.
  • High transfer ratio : need only 5 minuter to trasfer 1 minute of video over 4 land lines and 10 minutes over 4 cellular lines.
  • The first portable MPEG-1 store and forward capable of sending full motion, news broadcast quality video, at 25/30 fps with high quality sound.
  • With the DR 3000, it's possibleto send a sample of the production to the customer miles away, who will be able to play back the video and the audio without the waste of time and money sending tapes by courier for approvals.
   
 
Mpeg Video Transmission system
DR 3000 TT
Video specifications
Key Features: Live 30 fps (NTSC) 25 fps (PAL) video Transmission One way and bidirectional versions available Cost effective realtime MPEG-2 or MPEG -1 encoding and decoding Cd Quality stereo audio Data rates from1.0 to 15 Mb/s Multiple video inputs ; composite ; Component, S-Video or D1 Dos, Windows or Win 95 user interface SNMP network management Nertwork interfaces supported include t1, E1 V.35 EIA530 Ethernet and atm/oc-3 Whiteboard Function for annotation and screen sharing. Alarms for remote monitoring Remote pan/tilt/zoom camera control (optional)
  Uses :
Remote weather cams Cable headend feeds Fast breaking news feeds high end video conferencing distance learning broadcasting over a LAN or WAN Telemedicine Video surveillance
  Benefits
High quality MPEG compressed video at a reasonable price Configurable to meet your needs and network field proven relalible systems most advanced systems on the market today Simple to add capacity Easy upgrade from Mpeg-1 to Mpeg-2  
DVR 5000

Main features and Benefits

  • Highest quality field portable video record available
  • cost effective direct replacement for high end field portable Digital Betacam ™ or MII video tape recorders.
  • No tampe means : No more clogged heads, dropouts, tape path cleaning, head replacement or maintenance.
  • Cd quality stereo audio
  • Up to 6 hours of d1 4:2:2 quality storage ( using Mpeg -2 ) on 2 each internal removable hard drives. ( 3 hr / drive)
  • Sony standard remtore control emulation via 9 pin RS-422A port
  • Available in 4 basic version
  • Jpeg Mpeg-1 Mpeg-2 1/2 d-1 & Full D-1
  • Easy upgrade path from one version to another.
 

  VOD on air by AVT video server for broadcast applications

  This package is been developed to gieve a simple and reliable system for broadcast of spots and infomericals stored in advance on Video servers or Audio Servers. Using a pc with Windows ™ the software controls Play List for on air completely independent for each channel. Single commands for th play list. The remote connection allows the control of the system throught dedicated or switched telephone lines. The status of single channels of the server is monitored on the PC and at any moment it is possible to interact with the status of the single channel STOP PAUSE NEXT. The single play list can be created using any word procesor, spreadsheet or database usign a simple comma delimited data base. this simple techonology allow any station to create programming on any PC in the station.  The start of the various programs can be manual from keyboard iput , automatic ( related to time and date) controls or GPI coming from any existing system. The software is completely re-configurable upon request Standard supported

  • AV 50 Stream Logic Mpeg2/1 Video server min. 1 video ch. + audio stereo max. 16
  • AV 100 Stream Logic Mpeg2/1 Video server min. 1 video ch. + audio stereo max. 16
  • AV 200 Stream Logic Mpeg2/1 Video server min. 1 video ch. + audio stereo max. 16
  • AVT 16 AVT Mpeg Musicam L 2/1 Audio server min 1 ch audio stero max 8
 

DVR 6000 All digital ( no tape) D-1 Video Recorder

  Video specifications

Main Features and Benefits: Cost effective direct replacement for D1, D2 D3 D5 Mii Digital Betacam ™and Betacam Sp ™ video recordes for general use as well as commercial insertion , edit & animation use. No tamp means no more clogged heads, dropouts, tape path cleaning , head replacemtn or maintenace Up to 20 hours of d1 4:2:2 (CCIR 601) quality storage on 6 internal drives (one removable ) with (Mpeg-2) version . Over 50 additional hours with basic (Raid ) video server option up to 250 hours maximum. Uses industry standard SCSI AV rated hard drives ( no special certified drives required9. Simple standard VTR operation via exclusive Colby touch screen and industry standard jog / shuttle knob. Titable and remotable front control panel low power consumption and super powered fan system assure reliable long term operation. Cd quality stereo audio with front mounted Vu meters Sony standard remote control emulation via 9 pin RS- 422 A port Available in 5 basic version:

  • full D1 Quality jpeg
  • 1/4 D1 quality Mpeg-1
  • 1/2 D1 quality Mpeg-2
  • Full D1 quality Mpeg-2
  • Play only Mpeg-1 and Mpeg-2
 Easy upgrade path from one version to another .  

Common to all Models  

Technical Specifications

  Video inputs and ouputs (all BNC) Composite Component (Y,Y-R, Y-B) Digital Serial component, D-1 Monitor output Genlock input   Audio input (all XLR) Left & right 600 ohm balanced PGM in. Audio Outputs Left & Right 600 Ohm Pgm Out Left & Right 600 Ohm Monitor out   size 10.5" H x 17.5 " W x 24 " deep 110/220 VAC at 350 Watt Optional Rack Mount brackets and slides Touch screen control panel     Digiset By A.V.T. Portable digital audio recoder   Portable digital audio Recorder with time code for movie and television production. Delveloped and optimized for recording of digital audio on the sound stage production or where a syncronization video /audio with time code interlock internal /slave external is required. Can store and keep track of audio clapboard with the relative Time code start point , with immediate playback capabilities in both " slave" and " free" modes Audio is stored on removable discs , for up to 16 hours of recoring time. Interfaces directly with X-Track digital editign software using the EDL and list of the clapboard in thext format, allowing an all digital transfer , thus avoiding analog trasfer. Also possible to export audio in linear format including the conversion of the EDL in CMX format The "Slave play" mode allows the immediate replay in synconization with external Time code wiht an adjustable offest as well as time code strt piint. X track is a trademark of Digigram Corp.