Doremi Labs disk recorders and servers

By Vladimir Mys and Aleksey Chernykh

Review contents:
Disk recorders: past, present and future DV MasStor — a new page in NLE history Hard disk recorder DataVideo DV Bank DN-100 New surprises from Doremi Doremi Labs disk recorders and servers Disk recording devices of Ikegami Whipflash2 disk recorder Panasonic DVD recorder Sony disk recorders

Digital recording of video material onto hard disks is becoming more and more popular. Now it has become standard for NLE workstations. Storage of video on hard disks always gives wider possibilities than magnetic tape. Huge video libraries with analog VTRs are simply replaced with multichannel video server which allows instant access to the hundreds of Gigabytes of material. One- or two channel digital disk recorders operate similar to professional VTRs but video is recorded onto the built-in hard disk instead of cassette. Disk recorders allow work with standard video interfaces like Composite, S-Video, Component and SDI. Ability of control via RS-422 and the use of time code make it possible just move from analog VTR to digital disk recorder with no difficulties.

All the professionals today who deal with broadcasting, re-broadcasting, news production and post-production and even cinema production realize evidence of replacement of the tape technologies with the digital server ones due to its huge technological and economical advantages.

But not everyone has enough will to make this move because most of systems existed today are working under Windows NT OS which is widely known for it’s “stable work”. Nobody wants to be a hostage of situation.

As an example of successful combination of convenience of operation, good price and reliability V1 systems of Doremi Labs can be taken. They have separated administrative and executive parts resulting in minimization of the whole complex dependence of computer problems.

Design version of V1 recorder

Doremi Company is the one of leading developers and manufacturers of digital video and multimedia disk recorders and servers. First models of these devices of V1 series were introduced in 1996 and mostly instant became popular. Now more than 5 thousands users explore V1 for broadcasting, animation, video and audio editing etc.

V1 disk recorders

If you spend much time for professional video editing and have no desire to wait while analog VTR find necessary time code point on the tape than there is a sense to replace VTR with digital recorder with hard disks as a medium for video material. Such device will immediately answer for command and allow finish current job faster. Additionally if couple of years later on necessity to use this device in the air control room will arise than it will be enough to connect it with control station and get full functional video server.

V1 series disk recorder models have the front panel with control buttons, jog/shuttle wheel, variable playback speed controller and optional LCD display. Control of V1 is realized via 9-pin Sony interface with precision of zero frames. Compatibility with Louth (Harris), Odetics, SGT and Etere protocols allows V1 to be used in automated air control room.

V1 series allows connecting of 2…3 built-in SCSI disks (hot swappable) and up to 15 external disks for each SCSI port.

Variant of V1 use for Slow Motion Replay

On NAB 2002 show multichannel MPEG-2 version of well-known M-JPEG format V1 disk recorder had been introduced which is dedicated to broadcast market. This device allows recording and reading up to 4 broadcast quality MPEG-2 streams (4:2:2, 50 Mbps) simultaneously. Also Doremi Company introduced most sophisticated disk recorder V1-UHD (720p, 1080i/p/sf@24/25/30) which is intended for uncompressed high definition video material operation with. This device is as simple in operation as traditional VTR. It allows to record material onto removable hard disks with D6 quality and higher. Technology used makes it possible to create HDTV servers at cost lower than HD VTRs do.

Functional features of V1 series digital disk recorders can satisfy wide needs of TV production and broadcasting.

Several ways of use:

• Slow Motion Sports Replay — during sports events live production main episodes must be quickly repeated with the ability of playback speed variation. At this moment recording of the game mustn’t be interrupted. Two-channel disk recorders are optimal for this task realization. Operator doesn’t need any time for tape rewinding to the point of clip start. While one channel plays out the event in slow mode another channel continues game recording;
• Broadcast Time Delay — due to the absence of large number of mechanical components inside digital disk recorder is well suited for Time Delay function. Device can be set into “loop” mode in which it can operate any amount of time. Maximum delay value is limited to compression used and hard disk space only;
• Playback Device for Projectors and Large Screen Displays — digital disk recorders allow playback of separate clips and creation of play lists. Video clip is created by defining in and out points. Set of video clips can be placed in definite order for play list creation. Instant access to the data allows playback clip sequence without interruptions. Such device can be set into “loop” mode and provide endless playback;
• Video and Key Channel Recording and Logo Insertion — two-channel digital disk recorder can operate in the mode when two channels work as single one. This function is used for rear projection channel (connection of logo generator, CG etc.);
• Still Store and Clip Store — single channel or two-channel digital disk recorder is well-suited device for thousands of graphics and video files storage. Storing information on hard disk allows get instant access to the large amount of different material. Using network resources and special software it is possible to get graphics files directly from graphics workstation in TIFF, TARGA, BMP formats;
• Immediate Replacement for any Format Video Tape Recorder — high quality digital disk recorders have all functions related to professional VTRs. Thus replacement of geting old tape equipment with new disk one will not affect the operation in terms of quality and reliability but add extra functionality to the existing ones. The use of VTR needs additional expenses for maintenance (video and audio heads replacement as well as parts of tape transportation mechanism). Absence of mechanical components in the digital disk recorder minimizes maintenance expenses.

Model line of digital disk recorders is presented by four different families each of which has its own modifications and varies by number of recording and playback channels. The main difference between families is data recording format.

V1 M-JPEG series is dedicated for deal with Motion JPEG format and allows compression rate range 2:1…34:1. V1 MP2 series works in MPEG-2 4:2:2@ML format (up to 50 Mbps). V1 U series operates with HD signals and supports 720p, 1080i (50/60 Hz), 1080p (24, 25, 30 fps) and segmented frames (sf) formats. Main advantages of these families:

• convenient interface;
• instant access to video;
• 4:2:2, 8- or 10-but uncompressed video recording (for V1 U);
• creation and unique naming of video clips and play lists;
• direct, loop and slow motion playback;
• recording onto hard disk, DVD-RAM, MOD;
• recording up to eight audio channels;
• cross-conversion between different formats: QuickTime, TIFF, TGA etc;
• control via Ethernet or RS-422 using standard protocols;
• different interfaces: Composite, S-Video, Component, SDI, HD-SDI, external synch input.

Multichannel V1 video server

In 2002 Doremi Company has announced new product — V1 Multi-Channel Media Server. Today this server is installed in more than 100 editing, presentation and broadcasting studios.

Multichannel video servers perform centralized control and quick access to video archives. Multiple channels can be used for simultaneous recording and playback of video. Each records is identified by unique name which simplifies archiving and quick use in air play lists. The comparison shows that automated broadcasting using VTRs requires expensive and complicated tape loading mechanism which leads to multiple times maintenance cost increasing. Users who can not by such mechanism need to pay for hand work of people performing loading and unloading of tape machines.

V1 server is the device with ability if instant access to huge libraries of recorded audio and video material. This server together with V1 series digital disk recorders is multichannel device for recording and playback of video. Server control is realized by means of Doremi Labs dedicated software applications or via popular automation systems. Using workstation connected to the network user can record or playback on any channel as well as do many other operations. V1 server is modular solution and can be upgraded up to 24 channels.

Full V1 Server consists of three parts:

• V1 Server reads out video and audio data stored on internal or external disk massive and transfers them for playback thru video channels. V1 Server is connected to external massive via Fiber Optic link which allows use of up to 126 hard disks on each controller;
• Video Channels is based on use of V1 series disk recorders. V1 Server allows connect up to 24 recorders;
• Control Software — software application of Doremi or popular automation systems of Louth (Harris), Odetics, SGT and Etere.

By Ovako Company