ViewCast 450E, 240E manual Efficient Video Rendering, Preview Pin to Video Renderer

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Osprey 240e/450e User Guide

Efficient Video Rendering

The following information is primarily useful to developers, but may also be helpful for those who want to fine-tune existing applications. If you are seeing poor rendering performance, in terms of either excessive CPU utilization or jerky, stuttering video, read this section.

There are at least four basic ways to render video from the capture driver onto the screen. They vary greatly in their efficiency, and applications do not always make the best choice of renderer.

In these descriptions it is assumed that you are using the AVStream driver’s Preview Pin. The results would be the same if you used the Capture Pin instead.

Preview Pin to Video Renderer

Figure 63. Video Renderer

Video Renderer is the oldest and simplest DirectShow renderer. It does not use DirectDraw in the rendering process, which makes it substantially slower than VMR7 described below. It is the default rendering pathway that is chosen when an application says Render without specifying a preferred pathway. For this reason, many applications deliver unnecessarily slow rendering performance.

Video Renderer works best when your output format is RGB rather than YUV, with the RGB format matched to your screen depth. On most modern systems that means RGB32 is the preferred format. If a YUV format is used, an extra filter, AVI Decompressor, will be inserted into the graph to convert the YUV to RGB. The driver can do this conversion faster internally.

Preview Pin to Overlay Mixer to Video Renderer

Figure 64. Overlay Mixer to Video Renderer

Compared to a direct connection of Preview Pin to Video Renderer, the combination of Overlay Mixer plus Video Renderer provides performance that is …different. It is hard to be more specific than that without reference to specific machines; refer to the data tables below.

This pathway is the only one that renders closed captioning correctly when a DShow CC or VBI pin is used rather than the driver’s internal rendering. For CC rendering, the output of the Line 21 filter connects to an input of the Overlay Mixer.

The best video format to use with Overlay Mixer is YUY2.

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Contents Osprey 240e/450e User Guide Page Contents AVStream driver reference information Osprey 240e Environmental specifications Osprey 450e Page Overview Limited WarrantyWarranties Reseller Pass ThroughMinimum system requirements System requirementsInstalling the driver Installation StepsInstalling the video capture card Custom installing AVStreamTo install the video capture card Digital Signature Not Found Window Accessing the Osprey Config Utility Setting Driver PropertiesInitial OspreyConfig user interface OspreyConfig’s initial processing sequenceSelecting a device for configuration Control used to open the properties Osprey Video Device Properties window tabs Understanding the device properties windowVideo Proc Amp InputVideo Decoder RefSizeDevices and global controls OspreyConfig utility to access devicesInput tab Input tabVideo Input CancelVideo Present Video StandardInput tab without AV option Osprey 450e AV option hardware add-on-deviceOsprey 450e Video inputVideo Standard field Video standardComposite camera Input Format analog inputsVideoGraph VideoCheckVideoGraph VbiGraphVideo Proc Amp Tab Video Proc Amp tabPowerLine Color EnableFrequency Anti Flicker Default BrightnessVideo Decoder tab Video Decoder tabOutput Enable Signal DetectedLines detected VCR InputRefSize tab Horizontal DelayHorizontal FormatCCIR-601 Horizontal FormatSquare Pixels Signal WSS Horizontal DelayWide Use WideScreenSource Width Source WidthVideo Type Format HW or SW Adds CPU Granularity Reference Size for Crop and Logo PlacementLine Ntsc Vertical Format Line Ntsc Vertical FormatFilters tab Currently UsingSimulStream DeinterlaceSimulStream option SimulStreamMultiple instances Osprey 240e/450e User Guide Deinterlace Adjust…Inverse Telecine Motion AdaptiveBackground − telecine and inverse telecine Current Using settings Currently Using groupFrame Algorithm Adaptive Deinterlace windowMotion Threshold Close Test ModeRestore Defaults Osprey 240e/450e User Guide Device tab Buffers Requested No-Video Test PatternDiagnostic Logging Diagnostic loggingTypical section of data Board Numbering Device InfoBoard Numbering Setting Driver Properties Timecode Video Marking ExtrasClosed Caption TimestampingCaptions tab Captions tabPin Select Render Logical White As Render Ntsc Closed Captions On VideoCC Pin CC PinFile and Color sub Tab Enable Key Color Enable Logo onLogo tab On File and Color Sub tabOsprey 240e/450e User Guide Pin Select File and ColorEnable Key Color Enable Key ColorPosition and Size WeightingOsprey 240e/450e User Guide Size and Crop tab Size and Crop tabDefault Output Enable CroppingReference Size Reference SizeFormat Horizontal Vertical GranularityEnable Cropping Enable CroppingRecalc button Default Output Size Default Output SizePage DirectShow AVStream driver reference informationAVStream Driver Reference Information Post-Processing mode Post-Processing modeAVStream Driver Reference Information Preview Pin to Overlay Mixer to Video Renderer Efficient Video RenderingPreview Pin to Video Renderer Video Mixing Renderer Preview Pin to VMR7Some Data Points Preview Pin to VMR9AVStream Driver Reference Information Color formats Video standards and sizesYUV format details Closed captioning CC Captioning via CC or VBI pinsDirect CC rendering on video Vertical Interval Timecode Vitc CC streaming interfaceTimecode Video Marking Vertical Blanking Interval VBI captureAudio driver Selecting the audio source and input volumeAudio Driver Audio properties Audio propertiesMono Source Mode Audio configurationAudio formats Audio playbackDual Mono Input reference level Audio levelOsprey 240e Appendix a Osprey hardware specificationsEnvironmental specifications Osprey 240e long back plate Osprey 450e back plate Osprey 450eAppendix a Osprey Hardware Specifications Appendix B Osprey 450e audio cable Mini-DIN Signal RCA ConnectorsPage Scrambled video image Appendix C TroubleshootingColor bars on video screen Cannot play back recorded audio Poor video quality at large frame sizesMultiple horizontal lines across video image Osprey 240e/450e User Guide Page Index Appendix C Troubleshooting Osprey 240e/450e User Guide Viewcast.com