TapelessVideoCapture

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Tapeless Video Capture

    <img alt="INGEX tapeless ingest in action..." src="%ATTACHURLPATH%/Ingex1.jpg" alt="Ingex1.jpg" width='530' height='405' />

INGEX tapeless capture in action...


What is 'Tapeless Capture' ?

  • Tapeless capture is recording video from the camera direct to a medium that is not tape.
  • Sometimes called D2D or Direct-to-Disk.
  • Some systems utilise Hard Disk as a storage medium. Some use Solid State memory for storage.
  • It is important to be able to distinguish between a recording medium such as tape or disk and a video format such as DV, HDV or MPEG.

Why go tapeless?

  • Improved workflow.
    • Video is instantly accessible on the computer. No capture from the device, its already there.
       * Video cannot be recorded over by mistake. You have to manually delete old footage to create space.
  • Video can be reviewed instantly in the field.
    • Some devices have an analogue video signal available which can be connected to a monitor or viewfinder.
    • You could review the recorded video by plugging in a laptop.
  • Quieter recording operation.
    • Solid state devices in particular are silent in operation.
    • Modern hard disks are also very quiet.
    • There will be no sound from the deck lacing the tape ready for record.
  • Convenience
    • These days most of us are editing video on computer and that video is mostly digital video.
    • The video data can be copied as conveniently as pictures from a digital stills camera.

Devices

  • There are many different types of devices available.
  • The type of device you choose depends on what you want to do with the video.
  • Hard disk devices capture Analogue, DV and HD and are good for capturing DV for editing.
     Have large capacity for longer recording time.
  • Solid state disk devices are suitable for harsh environments where there may be knocks or vibration.
     Often smaller capacities, so need to organise storage and workflow carefully.
  • DVD based devices are more suitable for home use where you would want to view video on TV quickly. Perhaps not really suitable for editing.
  • Portable video viewers. Some devices use MP4 and are quite cheap and good for watching video or for capturing video for the web. The recorded video will be heavily compressed and therefore not really good for editing. May be ok for YouTube.


Archival

  • Tapeless capture presents a new problem of what to do with the video once captured since the recording stage no longer provides a tape master from the camera.
     Again, it really depends on what you want to do with the video and how much you love it to be able to choose which archive method suits you.
  • Archiving video to Disk based storage.
    • External hard disks, preferably two, mirrored.
  • Archiving video to Tape based storage. (I hope you can see the irony here.)
    • Tape is still the archive medium of choice for long life and data integrity.
  • Archiving video to Network based storage.
    • Basically external disks but accessible as networked disks. The NAS (Network Attached Storage) will probably have disk mirroring available as a feature.


Conclusion

  • We talked about what tapeless capture is.
     It's recording video to something other than tape. eg. Memory cards, Hard Disk, Solid state Disk

  • Reasons for going tapeless.
    Convenience.
  • Types of devices.
     Hard Disk, Solid State and MP4 style.
  • Archival issues.
    Hard disk, Networked storage, Data Tape.
  • Seen the nNovia working..
  • What next?
     I have included a selection of additional information that you may find useful.

Additional information

I have in a few places used ball-park figures. If you need better figures, I have provided some links and other information is available from sources such as Google or Wikipedia.

Devices

NNovia A2D - http://www.nnovia.com / http://www.datavision.co.uk (UK Distributor)

    <img src="%ATTACHURLPATH%/nnovia.jpg" alt="nnovia.jpg" width='104' height='104' />
    <img src="%ATTACHURLPATH%/nnovia_cam.jpg" alt="nnovia_cam.jpg" width='130' height='104' />
  • Hard disk - May be possible to use solid state disk, see below.
  • Analogue to digital conversion.
  • Firewire IO
  • Analogue IO
  • Records DV or HDV
  • All outputs are 'live' so you can transcode from Firewire to Analogue and vice versa.
  • Has trigger input for interface to cameras VTR button.

Firestore

  <img src="%ATTACHURLPATH%/firestore.jpg" alt="firestore.jpg" width='116' height='116' />
  <img src="%ATTACHURLPATH%/firestore_cam.jpg" alt="firestore_cam.jpg" width='104' height='100' />
  • Hard-disk
  • Firewire IO
  • Records DV 25
  • Same device found rebadged on JVC Pro cams.

FFV

   <img src="%ATTACHURLPATH%/ffv.jpg" alt="ffv.jpg" width='122' height='96' />
   <img src="%ATTACHURLPATH%/ffv_pro.jpg" alt="ffv_pro.jpg" width='124' height='69' />
  • Hard-disk
  • Analogue IO
  • Firewire IO
  • Records MJPEG (DV 25?)

Citidisk

  <img src="%ATTACHURLPATH%/citidisk_hd.jpg" alt="citidisk_hd.jpg" width='92' height='110' />
  • Hard-disk
  • Firewire
  • Records DV 25

Archos

  • Solid state
  • USB 2 IO
  • Analogue IO on some models
  • Records MPEG MP4 (highly compressed)

Beetle DV 1850 - http://www.shining.com/

  • Hard-disk
  • Analogue to digital conversion.
  • Able to output in DV, DVCPRO 50, MPEG-2, 24p and in NTSC or PAL
  • RS232 / 422
  • Firewire
  • Records DV 25 / HDV

Camera solutions

There are a few tapeless camera solutions about at present.

  • Panasonic P2
    • Solid state
    • DVCPRO 50 & HD
    • PCMCIA (PC Card based storage)
  • Sony XDCAM
    • Blu-ray recording medium.


Solid state disks

It may be possible to replace the hard disk in some recorders with a solid state replacement. Solid State Devices (SSDs) are more expensive. Typically in the 200-300 region. And can be about half the (write) speed of a hard disk.

Here are some possibilities.

  • Samsung 32Gb and 64Gb
    • Drop in replacement for ATA disk.
      * Write speed slower than disk but may be fast enough for video.

Archive devices

Although it may seem bizarre to discuss tape archive devices in a Tapeless Capture discussion, tape is still the medium of choice for large capacity storage of data and video data.

It may be that you decide that a hard disk archive solution works for you or maybe a solution where video is archived to disk and backed up to tape.

I have purposely decided not to include recordable DVD devices in this list as I do not believe that they offer enough reliability for long term data storage.

  • LTO Tape
    • Capacities from 200Gb to 19.2Tb
    • Moderately expensive. Approx �250 to �4000 on eBay depending on model.
    • Appears to be a good reliable format.
    • Media industry adoption. (BBC use it. see Ingex project http://ingex.sourceforge.net/ )
  • DLT Tape
    • Capacities 0.1Gb to 160Gb
    • Approx �300 to �1000 on eBay.
    • Reliable proven tape technology.
    • Now a little old and not as capacious as LTO
  • External Hard disk
    • Capacities 80Gb to 1Tb
    • Approx �60 to �200
    • Single disk, so potentially dangerous unless you buy two and mirror them.
  • External NAS (Network Attached Storage)
    • Capacities 500Gb to 2Tb (for the purposes of this document.)
    • Approx �100 to �500
    • Some solutions come with RAID-0 filesystems for reliability.

Quick look at data formats and rates

To put it all into perspective...

  • DV
    • 720x576 25fps
    • 25Mb/s
    • DCT I-Frame encoding.
    • Color depth: 4:1:1 8 bit
    • 5:1 compression.
  • HDV
    • HD 1080/50i
    • 25Mb/s
    • MPEG-2 encoding
    • Color depth: 4:1:1 8 bit
    • 40:1 compression. (Approximately varies depending on frame size and other factors)
  • Digibeta
    • 720x576 25fps
    • 90Mb/s
    • DCT encoding
    • Color depth: 4:2:2 10 bit
    • 2:1 compression.
  • CCIR601 (ITU-R BT 601) digital video
    • SD 720x576 25fps
    • 216Mb/s
    • 8 bit uncompressed video
  • SDI
    • SMPTE 259M SD-SDI 270 Mbit/s, 360 Mbit/s, 143 Mbit/s, and 177 Mbit/s (480i, 576i)
    • SMPTE 344M -- 540 Mbit/s (480p, 576p)
    • SMPTE 292M HD-SDI 1.485 Gbit/s, and 1.485/1.001 Gbit/s (720p, 1080i)
    • SMPTE 372M Dual Link HD-SDI 2.970 Gbit/s, and 2.970/1.001 Gbit/s (1080p)
    • SMPTE 424M 3G-SDI 2.970 Gbit/s, and 2.970/1.001 Gbit/s (1080p)


Interesting links

-- Main.BruceJames - 20 Jul 2007

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