The PDFCOMPRESSION structure provides information about PDF compression options.
typedef struct tagPDFCOMPRESSION
{
L_UINT uStructSize;
L_UINT32 dwFlags;
PDFCOMP_1BITCOMPTYPE comp1Bit;
PDFCOMP_2BITCOMPTYPE comp2Bit;
PDFCOMP_PICTURECOMPTYPE compPicture;
L_INT nQFactor;
} PDFCOMPRESSION, *LPPDFCOMPRESSION;
Size of this structure in bytes, for versioning. Use the sizeof() operator to calculate this value.
Flag that indicates which members contain valid data. You can combine values when appropriate by using a bitwise OR ( | ). The following are valid values:
Value | Meaning |
---|---|
PDFCOMP_1BITCOMPTYPE_ENABLED | [1] The comp1Bit member indicates the compression type to use for 1-bit segments/images. |
PDFCOMP_2BITCOMPTYPE_ENABLED | [2] The comp2Bit member indicates the compression type to use for 2-bit segments/images. |
PDFCOMP_PICTURECOMPTYPE_ENABLED | [4] The compPicture member indicates the compression type to use for Picture Compression segments/images. |
Value that indicates the compression type to use for 1-bit segments/images. For possible values, refer to PDFCOMP_1BITCOMPTYPE.
Value that indicates the compression type to use for 2-bit segments/images. For possible values, refer to PDFCOMP_2BITCOMPTYPE.
Value that indicates the compression type to use for Picture segments. For possible values, refer to PDFCOMP_PICTURECOMPTYPE.
QFactor to used with JPEG Compressions types. For a list of possible values, refer to Compression Quality Factors.
LPPDFCOMPRESSION is a pointer to a PDFCOMPRESSION structure. Where a function parameter type is LPPDFCOMPRESSION, declare a PDFCOMPRESSION variable and pass the variable's address in the parameter. Declaring an LPPDFCOMPRESSION variable is necessary only if the program requires a pointer.
The comp1Bit, comp2Bit and compPicture members are valid only if the appropriate value is set in dwFlags. This lets you set the compression type for 1-bit segments, for example, without affecting the compression of 2-bit or picture segments.