AVStream Driver Reference Information

The driver has three built-in user-accessible controls that affect Closed Captioning.

∙On the RefSize property page, in the control group shown below, 480-line video must be selected and the radio button to start video at either Lines 23/286 or Lines 22/285 must be selected.

∙On the Captions property page, most of the controls relate to the driver’s internal direct rendering on video. The following control selects field 1 or field 2 as the field to be streamed through the CC pin. This control is per-filter; both available pins on the filter are set the same way. For SimulStream users, the pins on different filters can have different settings.

∙On the Device -> Extras… property page, you have the choice to set with Normal or AVI- Compatible timestamping of Closed Caption samples.

This control is a workaround to an apparent problem in DirectShow – if you attempt to capture a CC character pair stream to an AVI file with Normal timestamping, the file becomes extremely large and the capture will fail within a few seconds. The AVI-Compatible mode allows capture of CC to AVI.

Unfortunately, the problem with timestamping means that time synchronization between the video and CC streams depend on their physical interleaving in the file, so that time synchronization is poor. If the AVI file is set up to be non-interleaved, synchronization is not good. If the AVI file is set up to be interleaved, synchronization is poor.

For all applications other than capture to AVI, this control should be set to Normal. WME9 among others requires the Normal setting if CC is used.

Windows Media Player does not play back an AVI file with an embedded CC stream. The following GraphEdit filtergraph plays back an AVI file containing a video stream plus a CC stream, with the CC rendered on the video:

Direct CC rendering on video

The driver can render closed captions directly onto capture or preview video. The captioned video can be encoded, written to file, or rendered directly to the screen.

70

ViewCast

Page 75 Page 77
Page 76
Image 76
ViewCast Osprey-450e, Osprey-240e manual Direct CC rendering on video
Page 75 Page 77

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.
Top Page Image Contents