CDBITMAPHEADER - Header record for a Bitmap ----------------------------------------------------------------------------------------------------------
#include <editods.h>
Definition :
typedef struct {
LSIG Header; /* Signature and Length */
RECTSIZE Dest; /* dest bitmap height and width in PELS */
RECTSIZE Crop; /* crop destination dimensions (UNUSED) */
WORD Flags; /* CDBITMAP_FLAGS (version 2 and later) */
WORD wReserved; /* Reserved for future use */
DWORD lReserved; /* Reserved for future use */
WORD Width; /* Width of bitmap in PELS */
WORD Height; /* Height " " */
WORD BitsPerPixel; /* Bits per PEL, must be 1,8 or 16 */
WORD SamplesPerPixel; /* For 1 or 8 BPP, set to 1.
For 16 BBP, set to 3 */
WORD BitsPerSample; /* For 1 BPP, set to 1. For 8 BPP,
set to 8. For 16 BPP, set to 5 */
WORD SegmentCount; /* Number of CDBITMAPSEGMENTS */
WORD ColorCount; /* Number of entries in
CDCOLORTABLE. 0-256 */
WORD PatternCount; /* Number of entries in CDPATTERNTABLE.
Set to 0 if using C API. */
} CDBITMAPHEADER;
Description :
A rich text field may contain a bitmap image. There are three types, monochrome, 8-bit mapped color, and 16-bit color; a gray scale bitmap is stored as an 8-bit color bitmap with a color table having entries [0, 0, 0], [1, 1, 1], . . . , [255, 255, 255]. All bitmaps are stored as a single plane (some graphics devices support multiple planes).
Color tables must be provided for 8-bit color bitmaps (which includes gray scale bitmaps); no color table is needed for monochrome or 16-bit color bitmaps. In 16-color bitmaps, 1 word of 16 bits is stored for each pixel. The high-order bit of this word will be 0. The rest of the word is divided into 3 fields of 5 bits each to store the Red, Green, and Blue color values, allowing 32 levels per color.
Release 2.0 of Notes used version 1 of the Notes graphics drivers. In Release 3.0 of Notes, version 2 of the graphics drivers allowed omission of the color table for 8-bit color bitmaps that only used the 16 standard Windows colors. In this case, the "Flags" word of the CDBITMAPHEADER will have the bit CDBITMAP_FLAG_REQUIRES_PALETTE set to 0.
In order to be displayed, a CDGRAPHIC record must precede a CDBITMAPHEADER record. A bitmap begins with a CDBITMAPHEADER record which defines the size and display characteristics.
Header Tag identifying this as a CDBITMAPHEADER record
Dest Destination bitmap height and width in pixels
Crop Reserved
Flags If CDBITMAP_FLAG_REQUIRES_PALETTE is set, the color table is required
wReserved Reserved
lReserved Reserved
Width Width of bitmap in pixels
Height Height of bitmap in pixels
BitsPerPixel Bits per pixel - must be 1, 8, or 16
SamplesPerPixel For 1 or 8 bits per pixel, this is set to 1; for 16 bits per pixel, 3
BitsPerSample For 1 bit per pixel, this is set to 1; for 8 bits, 8; for 16 bits, 5
SegmentCount Number of CDBITMAPSEGMENT records
ColorCount Number of entries in the CDCOLORTABLE record (0-256)
PatternCount Number of entries in the CDPATTERNTABLE (0-64)
The CDBITMAPHEADER may be followed immediately by an optional CDTRANSPARENTTABLE record, which is subsequently followed by an optional CDCOLORTABLE record, an optional CDPATTERNTABLE record, and one or more CDBITMAPSEGMENT records containing the compressed bitmap data. Details of the basic compression scheme are provided in the description of the CDBITMAPSEGMENT record.
Bitmap data may also be compressed by using a pattern table. See the description of CDPATTERNTABLE for details. A bitmap using a pattern table cannot be created using the C API; the PatternCount field must be set to 0.