CODECVIDEOHEADER

This structure is the video CODEC header and it describes the data format of either the source video or the destination video. It is used on the MMIOM_CODEC_OPEN message.

 typedef struct _CODECVIDEOHEADER {
   ULONG      ulStructLen;      /*  Structure length. */
   ULONG      cx;               /*  Width of bitmap. */
   ULONG      cy;               /*  Height of bitmap. */
   USHORT     cPlanes;          /*  Number of planes. */
   USHORT     cBitCount;        /*  Bits per pel. */
   ULONG      ulColorEncoding;  /*  Color encoding. */
   GENPAL     genpal;           /*  Generic palette. */
 } CODECVIDEOHEADER;
 
 typedef   CODECVIDEOHEADER   * PCODECVIDEOHEADER ;

ulStructLen (ULONG)

This field indicates the length of the CODECVIDEOHEADER structure.

cx (ULONG)

Specifies the width of the bitmap, in pels.

cy (ULONG)

Specifies the height of the bitmap, in pels.

cPlanes (USHORT)

Specifies the number of planes. The value is normally set to 1.

cBitCount (USHORT)

Specifies the number of bits per pel. Valid values are 1, 4, 8, 16, and 24.

ulColorEncoding (ULONG)

Color encoding. If zero is specified the default is assumed.

   MMIO_RGB_5_6_5
       Each pel is an RGB_5_6_5 data type. 
MMIO_RGB_24
       Each pel is an RGB_24 data type. 
MMIO_YUV_4_1_1
       Each pel is a YUV_4_1_1 data type. 
MMIO_YUV_24
       Each pel is a YUV_24 data type. 
MMIO_COMPRESSED
       The data is compressed. 
MMIO_PALETTIZED
       The data is palettized. Number of bits per pel specified in cBitCount. 

genpal (GENPAL)

For the pSrcHdr field of CODECOPEN it contains the video stream palette. For the pDstHdr field of CODECOPEN it contains the destination color space (for example, the physical palette if the CODEC_DIRECT_DISPLAY capability flag is set). The ulStartIndex field of the GENPAL structure is always NULL. The prgb2Entries field of the GENPAL structure is NULL when the number of colors exceeds 256.