Video Capture Requirements

This section summarizes both the basic hardware design features for video capture and the specific features for PC 97. Video capture and playback are not required for PC 97. However, if this feature is implemented, the requirements in this section must be met.

For requirements related to digital cameras and other digital image input devices, see the "Scanners and Digital Cameras" chapter in Part 4 of this guide.

20. Wave audio capture

If the video capture device supports wave audio capture, it must support the waveform audio command set defined in the Win32 SDK.

21. Synchronized audio and video capture clocks

Genlock capabilities are recommended to prevent problems that occur when there is no clock communication between video and audio cards. Notice that in professional video, the audio clock is usually derived from the video clock.

22. Time code reading

Time code is a standard representation of time developed for the video and film industries. Time code is an absolute time format expressed in hours, minutes, seconds, and frames as required by frame-accurate video editing applications.

• For NTSC-based systems, the defining standard for time code is ANSI/SMPTE 12M. Both drop and non-drop frame formats should be supported.
• For PAL-based systems, the defining standard is IEC 461. For film, the defining standard is SMPTE Recommended Practice RP 136.

23. WDM imaging minidriver

Each video input or capture device must have a WDM imaging minidriver that has passed WHQL testing.

24. All general device requirements for video components

These are defined in the "Video Components Basic Requirements" and "PC 97 Design for Video Components" sections earlier in this chapter.