Creating a Tune Request (C++) This topic applies to Windows XP or later. It is preferable to get a preconfigured tune request from a database. However, you can construct a tune request from scratch if you know the particular network type that you want to support. To create an ATSC tune request, do the following: Create a system tuning spaces collection.
Enumerate the tuning spaces to find the ATSC tuning space. Use the ATSC tuning space to create a new tune request. The following example omits any error checking. Long lChannel = 46; // Use whatever channel number you like. As this example shows, when the application builds the tune request, it must target specific network types. Writing Digital TV Applications with DirectX. This section describes how to build digital TV filter graphs for down-level platforms in which the Video Control is not available. For these platforms, the application must the graph manually, by adding and connecting each filter. Note that the Capture Graph Builder object does not support digital TV graphs. Obtain a Tune Request Create the Network Provider Filter Analog Tuning Spaces The AuxInTuningSpace tuning space represents an auxiliary video input or "AuxIn".
For analog graphs, ignore the rest of this section. Submit the Tune Request to the Network Provider // Query for ITuner. Add and Connect the Remaining Filters After the Network Provider has been configured with a tune request, you can add the remaining filters to the graph. Define Default Preferred Component Types A "component" refers to a program substream. Select a Substream Digital Tuning After the initial tune request has been submitted, subsequent tuning is performed by submitting a new tune request to the Network Provider. TV Technologies Application Interface.
The most important concepts in Microsoft® TV Technologies are the Video Control and the Microsoft Unified Tuning Model. Both are shown in the following illustration. The Video Control is an ActiveX® control that handles television tuning, DVD and file playback, and stream buffering. Internally, the Video Control creates a DirectShow filter graph. It also creates various helper components that manage the filter graph. These components are grouped into three categories: Input devices represent data sources, such as a TV tuners.Output devices represent renderers, such as video renderers or audio renderers.Features represent additional services that DirectShow can provide, such as closed captioning or IP data services.
The Unified Tuning Model is an API that defines tuning on any type of network, using any kind of compatible device. Related topics. TV Technologies. Purpose Microsoft TV Technologies enables the rapid development of digital and analog TV applications on the Windows platform. It consists of several components provided by Microsoft, along with specifications for additional components to be provided by third parties. Microsoft TV Technologies provides built-in software support for all major analog and digital broadcast standards, including ATSC, DVB, NTSC, PAL, SECAM and more. Full support is also provided for IP data services and closed captioning. Applications based on Microsoft TV Technologies are de-coupled from the details of tuning and are therefore network-independent.
Note This documentation assumes that the reader has a basic understanding of the analog, ATSC, and DVB broadcast standards, as well as MPEG-2 transport streams in general. In this section Additional resources Media Technologies for Windows. Visual Studio Professional 2012. TV Tuner Filter. Tuner - MSDN Search.