The all-in-one video-over-IP stage box.

V__link4 — the way to transport production-quality video over IP networks.

Conceptually, the V__link4 is designed to provide a one-box-solution for all the requirements of IP-based stage boxes including video and audio signal transport and processing. It includes everything from Video-over-IP coding to various monitoring and processing tools. All designed for one purpose: to provide a tool that increases the flexibility of any broadcast application, while saving valuable rack-space, set-up time and production costs. With its virtual cabling capability, V__link4 immediately brings IP infrastructure advantages and cost savings, providing an unparalleled degree of flexibility and scaleability.

Lawo V__link4. The all-in-one video-over-IP stage box.

Signal contribution for realizing tomorrow’s visions already today.

With the performance and maturity of today’s IP network technology, video-, audio- and control-over-IP are becoming the solution of choice for many applications. Designed for "classic" applications like video contribution from a stage box or a stadium to an OB truck or from a studio to a control room, IP technology provides economic and operational advantages.

The Lawo V__link4 is the ideal tool for achieving this vision of IP-based broadcast production today, providing an easy and secure migration path from today's SDI-based infrastructures to IP. The device combines a fully bi-directional, four-channel Video-over-IP interface, four local SDI inputs and outputs, along with all the processing tools usually needed when contributing video and audio to a broadcast production.

The most important highlights - Everything at a glance

  • Multiple Video-over-IP Encoding and Decoding: 4x Raw / VC-2* (DiracPro); in parallel 4x MJPEG* multicast for monitoring applications (multicast / encoding only)
  • Integrated switch fabric, switching capacity 40 Gbps, 2x 10 Gbit Ethernet and 4x 1 Gbit Ethernet (2x incl. PoE)
  • Frame synchronization for each channel
  • Frame Phasing, Line Phasing
  • Variable audio and video delays for each channel
  • Embedding and de-embedding incl. SRC for each channel
  • RGB Color Correction & Proc Amp for each channel*
  • Two Surround-to-stereo Downmixers per Embedder
  • Dolby® E Auto Aligner*
  • Quadsplit Multiviewer*
  • Waveform and Vectorscope display*
  • Timecode Insertion, Test Pattern Generator and Video ID Generator for each channel
  • Timecode Generator
  • Sync Generator, PTP Grandmaster with Ref GM function*
  • AV Sync Measurement* (Vistek® VALID8 compatible)
  • Network Sounding*

* optional feature

Video-over-IP contribution.

The Lawo V__link4 provides four 3G / HD/ SD SDI inputs and four 3G / HD / SD SDI outputs for interfacing to external video equipment. The device is designed to convert these signals into IP streams and vice versa. These streams can be transported via standard Layer 3 IP LAN environments. V__link4 provides parallel encoding and de-coding in RAW or VC-2 (DiracPro) for local production and parallel encoding in MJPEG for low-latency monitoring applications. The IP-based approach allows easy signal routing via Lawo’s VSM control and monitoring system or via other external master control systems. No rewiring is needed as long as all devices are connected to the network. Since the device is based on a real network technology with multi-cast capability, it allows easy transmission of signals to multiple outputs within the network.

The V__link4’s coding engines are designed to meet the highest demands in video quality and signal transport reliability. Port redundancy with SMPTE2022-7 compliant hitless merge switching ensures signal availability and quality. Format and quality of the IP video streams can be configured individually to meet the optimal ratio between picture quality, latency and bandwidth. The 6 Ethernet ports are connected to an internal switch allowing to “tunnel” through the 10GBit any IP traffic such as camera control, RAVENNA streams or even office and internet IP traffic.

Supported video transport modes:

  • Raw mode for transparent transport of uncompressed, full production quality video with the lowest latency. SMPTE 2022-6** compatible. Full code stream bit rates: HD 1.5 Gbps, 3G 2.97 Gbps
  • Ultra low latency mode for transporting production quality video with ultra low latency VC-2 (DiracPro) Codec,  end-to-end delay incl. encoding and de-coding < 32 video lines
  • MJPEG mode for monitoring and IP-TV applications. MJPEG Encoder, full code stream bit rates typ. 60 Mbps, end-to-end delay with V__view_app < 3 frames.
  • Full support of source-timed frame accurate switching of SMPTE2022-6 video*
  • Full support of the AIMS roadmap

* optional feature

** without FEC

Supported audio transport modes:

  • AES67
  • Embedded SMPTE 2022-6

Unified control for IP signal routing.

V__link4 and V__remote4 devices are managed with the Lawo VSM broadcast control and monitoring system. This enables convenient management of all V__line video streams, as well as the audio streams from A__line Audio-to-IP interfaces from one unified control GUI. VSM provides intuitive video and audio stream setup with a routing function that operates just like a standard router control panel. The VSM system hides the complexity of the IP network from the user, and provides immediate advantages: Reconfigure without the need to touch any physical cables, setup streams, and control parameters all with the use of a mouse-click or touch-screen control. In addition, the VSM system also includes a comprehensive range of hardware control panels.



Powerful tools for video contribution

  • Video / Audio Router provides an internal 8 x 8 video routing matrix (4x SDI + 4x IP) and a 384 x 384 audio routing matrix.
  • Internal switch with 2x 10G Ethernet and 4x 1G Ethernet ports (2x PoE) for any network application.
  • IP streaming engine for video and audio signals with raw format video encapsulation (SMPTE 2022-6).
  • Sync-Generator for precise clocking of broadcast infrastructures.
  • Virtual BLACKBURST for sync distribution via LAN.
  • Frame-Synchronizer for syncing incoming independent free running signals to the same reference.
  • 3G conversion down-converts 3G to 1080i for 10GE streaming applications.
  • Variable Video & Audio Delays for compensating latencies and lip-sync matching between incoming or outgoing audio (up to 320 ms delay) and video (up to 8 frames delay) signals. In Delay Auto Mode the audio delay can be set to automatically follow the video delay.
  • (De-) Embedding with SRC to embed, de-embed and shuffle any of the 16 audio channels within the 8 SDI input/output streams simultaneously. Audio interfacing to mixing consoles or external audio routers via MADI and AES67RAVENNA.
  • Dolby E® Auto Aligner to automatically adjust the timing of Dolby streams.
  • Surround Downmix for providing two automated Lawo-quality 5.1 / 7.1 to stereo downmixes per embedder.
  • Timecode Insertion provides selectable ATC LTC / VITC1 / VITC2 insertion from an input signal or free run mode or from internal Timecode Generator.
  • Test Pattern and Video ID Generator provide video ID insertions (text, source, date, timecode, time of day) and color bar test pattern as well as a selection of audio test
    tones and AV Sync test pattern.
  • Thumbnail Previewing to provide motion previews of video signals. The thumbnails are available via IP and can be displayed on the V__link 4 GUI, external master control systems or PCs.

Optional Features

  • VC-2 CODECS for production quality, bandwidth-reduced, low latency IP streaming (suitable for multiple coding generations).
  • SEAMLESS Protection switching for providing port and network redundancy with seamless protection switching
    (SMPTE2022-7 compliant)
  • CLEAN SWITCHING OPTION for full support of source-timed frame-accurate switching of SMPTE2022-6 video.
  • NETWORK SOUNDING for testing the WAN’s network performance in order to provide metrics for trouble-shooting and monitoring
  • REF GRANDMASTER generates a PTP for the complete network derived from an incoming video reference signal.
  • QUADSPLIT MULTIVIEWER provides a high quality video and audio monitoring solution with true peak & peak metering, UMD and tally support via the unit’s MV video outputs (BNC / Display Port), displaying up to four video sources at the same time. The tally lamps can be controlled via Ember+, offering the possibility to integrate the MV tally in the overall tally system of your studio control system. It supports multiple colors (RGB) for multi tally configurations in enhanced TV productions
  • Waveform and Vectorscope Displays enable measuring and testing of video signals and evaluation of video adjustments processed within the V__link 4.
  • RGB & YUV Color-Correction and Proc -Amp to adjust the video signal to specific color requirements. High-quality algorithms guarantee perfect video signals.
  • AV SYNC MEASUREMENT is a high-end measurement tool for managing the precise synchronization of audio and video signals. It can create a V__line sync pattern and read / analyse three types of sync patterns: V__line, EBU and the Vistek® VALID8 pattern. Each SDI and IP input of the V__link4 can be used to read the incoming VALID signal.
  • DOLBY E® AUTO ALIGNER to automatically adjust the timing of Dolby® streams.

Intuitive device configuration

  • Web-GUI. Easy-to-understand HTML 5-based touch screen interface with live video monitoring that runs directly within the web browser. The GUI enables the operator to access all V__line devices from anywhere within the network.
  • Ember+ Control. The Ember+ protocol support enables the device to be controlled by external master control systems like BFE's KSC, Axon's Cerebrum or Lawo's Virtual Studio Manager. This allows the building of broadcast installations with an integrated user interface.


Video Interfaces

  • Video Signal Input/Output: 4x 3G/HD/SD-SDI inputs via BNC connector, 4x 3G/HD/SD-SDI outputs via BNC connector, 1x 3G/1080i MV/QS output via BNC, DisplayPort for local MV/QS monitoring
  • Video Reference Signal Input/Output: BB/Tri-Level, Loop thru, BB/Tri-Level output via BNC connector, IP
  • Video Standards:
    2.97Gbps Video Standards (1080p):
    1080p 60Hz SMPTE-424M, 425M Level A & Level B
    1080p 59.94Hz SMPTE-424M, 425M Level A & Level B
    1080p 50Hz SMPTE-424M, 425M Level A & Level B
    1.485Gbps Video Standards (HD):
    1080i 60Hz SMPTE-274M(4),-292M(D)
    1080i 59.94Hz SMPTE-274M(5),-292M(E)
    1080i 50Hz SMPTE-274M(6),-292M(F)
    1080p 30/29.97/25/24/23.976sf
    1080p 30Hz SMPTE-274M(7)-292M(G)
    1080p 29.97Hz SMPTE-274M(8)-292M(H)
    1080p 25Hz SMPTE-274M(9)-292M(I)
    1080p 24Hz SMPTE-274M(10)-292M(J)
    1080p 23.976Hz SMPTE-274M(11)-292M(K)
    720p 60Hz SMPTE-296M(1),-292M(L)
    720p 59.94Hz SMPTE-296M(2),-292M(M)
    720p 50Hz SMPTE-296M(2),-292M(M)
    270Mbps Video Standards (SD):
    576i 16:9 and 4:3 SMPTE-259M(C)
    480i 16:9 and 4:3 SMPTE-259M(C)
  • Video Reference: Analog Genlock High definition tri-level sync SMPTE-274M/296M or SD 1V BB SMPTE-170M/318M or SDI or IP-VidStream, IEEE1588 PTPv2+VideRef (RV or SMPTE2059*)
  • Return loss: SD: > 15dB; HD: > 15dB; 3G-HD: >15dB 5MHz-1.485GHz, >10dB 1.485GHz-2.97GHz
  • Cable length: SD: >350m (using Belden1694A), HD: >180m (using Belden 1694A),
    3G-HD: >120m (using Belden1694A)
  • Video Resolution: 10 bit 4.2.2

* future software release

Audio Interfaces

  • Audio Signal Input/Output: 2x MADI / AES10 optical in / out via LC connector front (redundant mode selectable); SDI embedded Audio via BNC connector, Ethernet
  • Audio Reference Signal Input/Output: BB/Tri-Level, WordCLK input via BNC connectors, WordCLK output via BNC connectors
  • Audio Standards: SMPTE 299 / 48, MADI / AES10, RAVENNA / AES67
  • Audio resolution: 24 bit




  • ATC (LTC. VITC1, VITC2) SMPTE12M-2, Binary group data SMPTE 309, AFD SMPTE2016, Closed-Caption SMPTE334, VBI data services /DTV descr. SMPTE334, Source-ID OBSspecial, Dolby E® Meta data SMPTE2020, ANSI/SCTE 104 SMPTE2010, DVB/SCTE VBI SMPTE2031, Teletext OP-47, User App ID DID C1&C4 (Y-HANC) (more on request)

IP Interfaces

  • Gigabit Ethernet: 4x RJ45 100/1000Base-T, 2x POE, 2+2 redundant operation selectable*
  • 10G Ethernet: 2x SFP+, redundant operation selectable*
  • Protocols: IPv4/UDP/TCP/RTP/RTCP, ARP, RSTP, LLD P, IGMPv2, DiffservTOS, IEEE1588 PTPv2 (transparent clock)
  • VLAN: port-based VLAN1 & VLAN2; assignable management port
  • Switching capacity: max. 40Gbps, video & audio content streaming max. 10Gbps

*future software release


  • VIDEO ENCAPSULATION (10 BIT 4:2:2): Raw (uncompressed) encoding and decoding (SMPTE2022-6 vs.
    RV) or VC-2 (DiracPro-LL) compressed encoding and decoding
  • Seamless protection switching (Hitless Merge, compliant with SMPTE2022-7)
  • Raw encoding & decoding: 4x video encoding bitrates 2.5 Gbps, 1.25 Gbps; latency < 1 line
  • MJPEG encoding (8 bit 4:2:2): 4x video encoding with stereo audio; bitrates no constant bitrate, constant quality level; latency < 2 frames
  • Thumbnailing & PPM: input/output JPEG thumbnails and PPm data
  • Audio Encapsulation: AES67 and RAVENNA audio streams (encoding AM824, decoding L16, L24, AM824); Encoding bitrates stream dependant; Latency synchronous operation < 2msec
  • AV Sync (Audio/Video): synchronous operation < 2msec
  • Video/Audio Output Synchronization: Genlocked to external clock reference, genlocked to IP PTP master clockbased reference, genlocked to SDI or IP input
  • Latency: video processing latency: max. 100 pixels; QuadSplit monitoring: 1 frame; audio latency (SRC disabled, synchr. operation): < 2 ms



Management and Monitoring

  • Protocols: HTTP, SNMPv1, Ember+, NMOS IS-04* , Syslog
  • USER INTERFACES: Embedded HTML5 user interface; optional V__fp 1 control panel
  • GPI: physical and virtual GPIs (via Ember+)


  • 2x Auto sensing 100 .. 240V VAC power supply 50/60 hz nominal on IEC connector < 130 w incl. 30 w PoE


  • Storage temperature -4° F to +158° F (-20° C to +70° C)
  • Operating temperature +32° F to +104° F (0° C to +40° C)
  • Relative humidity <= 90% non-condensing
  • Electromagnetic environment: E2 (EN55103-1,-2)

Frame Mechanics

  • Dimensions (H x W x D) 44mm (1 RU) x 481 mm (19“) x 458mm (18“)
  • Weight 4.9kg (10.8lbs)

Subject to change without prior notice, no responsibility is taken for the correctness of the details provided.

Download Lawo's Latest Products PDF