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PgScalerProps_t

Data structure that describes video overlay scaler properties

Synopsis:

typedef struct  {
    unsigned        size;
    unsigned        flags;
    PgColor_t       color_key;
    unsigned        reserved0;
    PgColor_t       color_key_mask;
    PhRect_t        viewport;
    PhDim_t         src_dim;
    unsigned        format;
    int             brightness;
    int             contrast;
    PgVideoAlpha_t  alpha[4];
    unsigned        reserved[10];
} PgScalerProps_t;

Description:

The PgScalerProps_t structure describes video overlay scaler properties. It includes:

size

The size of this structure; set this to:

sizeof (PgScalerProps_t)
  

flags

The flags include:

• Pg_SCALER_PROP_CHROMA_ENABLE -- enable chroma keying. When chroma keying is enabled, video output appears only where pixels drawn in the chroma-key color are present.
• Pg_SCALER_PROP_CHROMA_SPECIFY_KEY_MASK -- use the value of the color_key member, instead of the default returned by PgGetOverlayChromaColor(), as the chroma-key color.
• Pg_SCALER_PROP_DISABLE_FILTERING -- attempt to disable interpolation or filtering algorithms when scaling; scaling is instead performed using simple replication (scaling upwards) or dropping (scaling downwards) algorithms.
• Pg_SCALER_PROP_DOUBLE_BUFFER -- turn on double-buffering of video frames.
• Pg_SCALER_PROP_SCALER_ENABLE -- enable the video scaler output viewport.
• Pg_SCALER_PROP_TO_BACK -- tell the driver to put the scaler region behind all other scaler regions.
• Pg_SCALER_PROP_TO_FRONT -- tell the driver to put the scaler region in front of all other scaler regions.
• Pg_SCALER_PROP_DRAW_TARGETABLE -- allow Photon drawing output to be directed to the video scaler buffer. Note that only RGB data format is supported for targeting in this manner.

color_key

The chroma-key color (of type PgColor_t) to use when Pg_SCALER_PROP_CHROMA_ENABLE and Pg_SCALER_PROP_CHROMA_SPECIFY_KEY_MASK are set in the flags member.

color_key_mask

Not implemented.

viewport

A PhRect_t structure that stores the location and dimension, in desktop coordinates, of the video scaler output viewport.

src_dim

A PhDim_t structure that defines the width and height of the video data frames before scaling.

format

The format of the video frame data. This is analogous to the format member of the PgScalerCaps_t structure.

brightness

The brightness of the video output viewport. The range is 127 to -127, where 0 specifies normal brightness.

contrast

The contrast of the video output viewport. The range is 127 to -127, where 0 specifies normal contrast.

alpha[4]

Not implemented.

Classification:

Photon

See also:

PgColor_t, PgConfigScalerChannel(), PgCreateVideoChannel(), PgDestroyVideoChannel(), PgGetOverlayChromaColor(), PgGetScalerCapabilities(), PgNextVideoFrame(), PgScalerCaps_t, PgVideoChannel_t, PhDim_t, PhRect_t

"Video overlay" in the Raw Drawing and Animation chapter of the Photon Programmer's Guide