ViewCast Understanding Vertical Blanking Interval and Its Capture with Osprey Models
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AVStream Driver Reference Information

application. This capability requires custom programming. Refer to the Osprey AVStream SDK Users’ Guide. A sample SDK applet named TCApp illustrates the interface.

Figure 61. Timecode Video Marking

Timecode stamping must be enabled in the driver before it can be used, and the field and line number correctly set. To access the controls, go to the Device property tab and click Extras…

It is recommended that timecode marking be disabled when not in use, especially the auto search feature – on a slow machine it uses several percent of CPU bandwidth – especially if timecodes are not present.

Note: VITC and LTC – Longitudinal Timecode – are two distinct encoding systems, and this driver supports only VITC.

A suggested reference on timecode is Timecode: a user’s guide – 3rd ed., John Ratcliff, Focal Press, 1999.

Vertical Blanking Interval (VBI) capture

The Osprey AVStream driver provides DirectShow-compatible VBI pins. VBI data includes Vertical Interval Timecode (VITC) in both the NTSC and PAL worlds. In NTSC, line 21 Closed Captioning (although it is part of the video interval rather than true VBI data), is commonly treated as VBI data. In PAL, World Standard Teletext (WST) is encoded in the VBI data region.

The driver delivers VBI data as raw waveforms, which are then decoded by external DirectShow filters. DirectShow provides three filters under the classification “WDM Streaming VBI Codecs” that will decode data from VBI pins:

∙CC Decoder

∙NABTS/FEC VBI Codec

∙WST Codec

With the Osprey AVStream driver, either the CC pin or the VBI pin can be used to obtain closed caption data. If the VBI pin is used, an extra filter is required to turn the raw waveform into CC character pairs.

When SimulStream is not installed, the driver supports two VBI pin instances. In practice, a DirectShow Smart Tee Filter can be inserted into the graph to make any number of VBI pins. When SimulStream is installed, multiple VBI pins are allowed.

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Contents Osprey 240e/450e User Guide Page Contents Selecting the audio source and input volume Osprey 240e Environmental specifications Osprey 450e Page Warranties Limited WarrantyOverview Reseller Pass ThroughSystem requirements Minimum system requirementsInstallation Steps Installing the driverCustom installing AVStream Installing the video capture cardDigital Signature Not Found Window Page Setting Driver Properties Accessing the OspreyConfig UtilityOspreyConfig’s initial processing sequence Initial OspreyConfig user interfaceSelecting a device for configuration Control used to open the properties Understanding the device properties window Captions LogoSize and Crop OspreyConfig utility to access devices Devices and global controlsInput tab Input tabVideo Present CancelVideo Input Video StandardOsprey 450e AV option hardware add-on-device Input Tab without AV optionVideo standard group Input Format group analog inputsNotch Kill Video Proc Amp tab VideoProc Amp TabFrequency Anti Flicker Default Color EnablePowerLine BrightnessVideo Decoder tab Video Decoder tabLines detected Signal DetectedOutput Enable VCR InputRefSize tab Horizontal Format Horizontal Delay Horizontal DelaySource Width Source WidthReference Size for Crop and Logo Placement Line Ntsc Vertical FormatSetting Driver Properties SimulStream Currently UsingFilters tab DeinterlaceApply Help SimulStream SimulStream optionMultiple instances Show Filters Inverse Telecine Adjust…Deinterlace Motion AdaptiveCurrently Using group Motion adaptive deinterlaceAdaptive Deinterlace window Motion ThresholdSmooth Motion Sharp Motion Test ModeRestore Defaults CloseDevice tab No-Video Test Pattern Buffers RequestedTimecode Video Marking Diagnostic loggingExtras Closed CaptionOsprey 240e/450e User Guide Device Info Device InfoCaptions tab Capture Pin SelectCC Pin PreviewRender Ntsc Closed Captions On Video Render Logical White AsCC Pin CC PinLogo tab Enable Logo onFile and Color sub Tab Enable Key Color On File and Color Sub tabSetting Driver Properties File and Color Pin SelectEnable Key Color Enable Key ColorWeighting Position and SizeLogo position and size Size and Crop tab Size and Crop tabReference Size Granularity Granularity Alignment Format Horizontal VerticalEnable Cropping Enable CroppingRecalc button Default Output Size Default Output SizeAVStream driver reference information DirectShowAVStream Driver Reference Information Post-Processing mode Post-Processing modeAVStream Driver Reference Information Efficient Video Rendering Preview Pin to Video RendererPreview Pin to Overlay Mixer to Video Renderer Preview Pin to VMR7 Video Mixing RendererPreview Pin to VMR9 Some Data PointsAVStream Driver Reference Information Video standards and sizes Color formatsYUV format details Captioning via CC or VBI pins Closed captioning CCDirect CC rendering on video CC streaming interface Vertical Interval Timecode VitcVertical Blanking Interval VBI capture Timecode Video MarkingSelecting the audio source and input volume Audio driverAudio Driver Audio properties Audio propertiesAudio formats Audio configurationMono Source Mode Audio playbackInput reference level Audio Driver Appendix a Osprey hardware specifications Environmental specificationsOsprey 240e Osprey 240e long backplate Osprey 450e Osprey 450e backplateAppendix a Osprey Hardware Specifications Mini-DIN Signal RCA Connectors Appendix B Osprey 450e audio cablePage Appendix C Troubleshooting Color bars on video screenScrambled video image Poor video quality at large frame sizes Multiple horizontal lines across video imageCannot play back recorded audio Osprey 240e/450e User Guide Page Index Appendix C Troubleshooting Video rendering Viewcast.com

Osprey-450e, Osprey-240e specifications

The ViewCast Osprey series, particularly the Osprey-240e and Osprey-450e, represents a significant advancement in the field of video capture and encoding technology. These high-performance video capture cards are designed to meet the growing demands of professional broadcast environments, video production, and live streaming applications.

The Osprey-240e offers a compact design while delivering excellent performance. It is equipped with dual channel input capabilities, allowing users to capture multiple streams simultaneously. This feature is particularly beneficial for broadcasters and content creators looking to streamline their workflows. The Osprey-240e supports a variety of input formats including SDI and HDMI, ensuring compatibility with a wide range of video sources. Its robust encoding capabilities allow for real-time video streaming in HD resolution, making it suitable for live events, webinars, and other digital content delivery applications.

On the other hand, the Osprey-450e takes video capture to the next level with enhanced capabilities. It supports up to four channels of video input, making it an ideal solution for multi-camera setups. The Osprey-450e also boasts advanced encoding technologies that facilitate high-quality video compression without sacrificing performance. This model is particularly well-suited for enterprise-level applications where high-definition video quality is paramount. Users can experience lower latency and improved encoding efficiency, resulting in smoother viewing experiences for end-users.

Both models feature powerful drivers and software support that integrate seamlessly with a variety of video production and streaming applications. The Osprey series is designed with user-friendly interfaces, making it accessible for both seasoned professionals and newcomers alike. The cards are also compatible with many of the industry-standard software solutions, enabling users to harness the full potential of their video content.

These capture cards also prioritize reliability and durability, ensuring long operational life even under demanding conditions. Their efficient thermal management systems keep components cool during extended use, thereby enhancing performance consistency.

In summary, the ViewCast Osprey-240e and Osprey-450e deliver impressive features tailored for a range of video applications. Their support for multiple input channels, advanced encoding technologies, and strong software compatibility make them invaluable tools in the modern digital media landscape, solidifying their reputation among content creators and broadcasters alike.
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