C Structure Definition in PowerBasic

[John Sullivan]

I am new to PowerBasic. I am attempting to use a DLL called Konvertor,
which converts a PDF image into any one of a number of different types
like Jpg, TIFF, etc. The DLL is provided by http://www.logipole.com.

I am having a great deal of trouble getting it to work. Following is
the "C" Structure definition. My questions are:

1. How would this convert to a PB structure definition? Specifically the
Char* which I believe are string pointers and the BOOL?

2. Some C code to use the DLL follows the structure definition. Would I
use a VARPTR(PB structure) to call the function?

3. If the Char* are string pointers how do I load them in PB. Would I use:
DIM f_name as string
F_name = "c:\imagefile.pdf"
mystrut.filename = STRPRT(f_name)

4. Here is what I have come up with as to a DECLARE for PB:
DECLARE FUNCTION PDFtoXXX LIB "Konvertor_pdf2xxx.dll" ALIAS "PDFtoXXX" (lpParam AS DWORD) AS INTEGER
Is this correct?

Thank you for any help you can provide me.

John Sullivan

______________________________________________________________

This function converts a PDF file to another format.
The program must be linked with Konvertor_pdf2xxx.lib or
you can call directly the functions, they are exported.

typedef struct _tagPDF2XXX {

char* pdfFile;
char* pdf_password;
short pdf_dpi;
short pdf_first_page;
short pdf_nb_page;
short target_image_type;
short target_adjoin;
short trim;
char* target_folder;
short monochrome;
short gif_delay;
short jpeg_compression;
short jpeg_dpi;
short tif_compression_type;
short tif_dpi_H;
short tif_dpi_V;
short txt_columns;
short txt_mark_crlf;
short txt_format;
short txt_type;
short new_height;
BOOL keep_proportions;
short signature;
short signature_dissolve;
char* signature_mask;
char* temp_folder;
char* error_buffer;
} pdf2xxx;


// image compression types
#define NONE 0
#define ZIP 1
#define JPEG 2
#define FAX3 3
#define GROUP4 4
#define RLE 5

// target image types

#define _BMP 0
#define _FAX 1
#define _GIF 2
#define _JPEG 3
#define _JNG 4
#define _PCX 5

#define _PDF 6

#define _PGM 7
#define _PNG 8
#define _PPM 9
#define _PS 10
#define _SGI 11
#define _TGA 12
#define _TIFF 13
#define _TXT 14

// declaration

void PDFtoXXX(pdf2xxx *param);

int test(void) {
pdf2xxx param;
char version[512];
int ret;

// convert to an animated GIF, resizing the pages
ZeroMemory(error, sizeof(error));
ZeroMemory(&param, sizeof(param));


param.target_image_type = _GIF;
param.target_adjoin = TRUE;
param.pdfFile = "c:\\pdf\\test.pdf";
param.pdf_dpi = 75;
param.new_width = 150;
param.new_height = 65;
param.gif_delay = 1000;
param.target_folder = “c:\\converted”;
param.temp_folder = “c:\\temp”;
param.error_buffer = error;
ret = PDFtoXXX(&param);

------------------

[Tom Hanlin]

You can find information on translating from C types in the PB help,
under Data Types / Comparative Data types. As for question (4), can
you show us the original C declaration? Oh, I see. Like this:

DECLARE SUB PDFtoXXX LIB "Konvertor_pdf2xxx.dll" ALIAS "PDFtoXXX" (param AS tagPDF2XXX)

------------------
Tom Hanlin
PowerBASIC Staff