Quality

  • 项目

This structure describes a quality message by indicating Flood or Famine in the renderer and specifying the percentage of frames to drop or add to optimize the renderer's performance.

typedef struct{
  QualityMessageType Type;
  long Proportion;
  REFERENCE_TIME Late;
  REFERENCE_TIME TimeStamp;
} Quality;

Members

  • Type
    Either Famine or Flood, indicating that a downstream filter needs more or less data.
  • Proportion
    Value that specifies the rate at which DirectShow should continue to send media samples. The base value is 1000, which indicates there should be no change. A percentage increase or decrease from 1000 indicates the percentage of frames to add or drop. If this value is 800, for example, DirectShow will drop 20 percent of the incoming frames to match the renderer's speed.
  • Late
    If a famine exists downstream, this is the amount of time by which the stream is lagging.
  • TimeStamp
    Value that specifies the time when DirectShow created this structure, which is usually the start time on a video sample.

Requirements

DirectShow applications and DirectShow filters have different include file and link library requirements. See Setting Up the Build Environment for more information.

OS Versions: Windows CE 2.12 and later. Version 2.12 requires DXPAK 1.0 or later.
Header: Dshow.h.

Last updated on Wednesday, April 13, 2005

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