References ▼
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. | |
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 LPDFCompressor::SetCompression function.