PDFCOMPRESSION

typedef struct tagPDFCOMPRESSION
{
   L_UINT uStructSize; 
   L_UINT32 dwFlags; 
   PDFCOMP_1BITCOMPTYPE comp1Bit; 
   PDFCOMP_2BITCOMPTYPE comp2Bit; 
   PDFCOMP_PICTURECOMPTYPE compPicture; 
   L_INT nQFactor;  
} PDFCOMPRESSION, *LPPDFCOMPRESSION;

The PDFCOMPRESSION structure provides information about PDF compression options.

Member

Description

uStructSize

Size of this structure in bytes, for versioning. Use the sizeof() macro to calculate this value.

dwFlags

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

[0] 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.

comp1Bit

Value that indicates the compression type to use for 1-bit segments/images. For possible values, refer to PDFCOMP_1BITCOMPTYPE.

comp2Bit

Value that indicates the compression type to use for 2-bit segments/images. For possible values, refer to PDFCOMP_2BITCOMPTYPE.

compPicture

Value that indicates the compression type to use for Picture segments. For possible values, refer to PDFCOMP_PICTURECOMPTYPE.

nQFactor

QFactor to used with JPEG Compressions types. For a list of possible values, refer to Compression Quality Factors.

Comments

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.

This structure is used with the L_PdfCompSetCompression function.