Partager via

VMR9ProcAmpControl Structure

  • Article
 
Microsoft DirectShow 9.0

VMR9ProcAmpControl Structure

The VMR9ProcAmpControl structure specifies the image adjustments to be performed on a video stream. This structure is used with the Video Mixing Renderer Filter 9 (VMR-9).

Syntax

typedef struct _VMR9ProcAmpControl
{
    DWORD  dwSize;
    DWORD  dwFlags;
    float  Contrast;
    float  Brightness;
    float  Hue;
    float  Saturation;
} VMR9ProcAmpControl;

Members

dwSize

Size of the structure, in bytes. The value must be sizeof(VMR9ProcAmpControl).

dwFlags

Bitwise combination of flags from the VMR9ProcAmpControlFlags enumeration, indicating which properties the driver supports.

Contrast

Specifies the image contrast. Contrast alters the relative light-to-dark values in a picture. Functionally it maps the range of input values to a smaller or larger range of output values.

Brightness

Specifies the image brightness. Brightness, also called black-level setup, specifies the viewing black level. Functionally, it adds or subtracts the same number of quantizing steps (bits) from all the luminance words in a picture.

Hue

Specifies the image hue. Perceptually, hue corresponds approximately to "color." Functionally, hue is a phase relationship of the chrominance components. It is specified in degrees, with a nominal valid range from –180 to 180 degrees and a default value of 0.

Saturation

Specifies the image saturation. Saturation alters the color intensity of the image. Functionally it is similar to contrast, but operates on the chroma components of the image.

Remarks

The valid range of values for each property depends on the graphics device driver. Call the IVMRMixerControl9::GetProcAmpControlRange method to get the range for each property.

Requirements

Header: Vmr9.h.

See Also