eBookReaderSwitch/mupdf/docs/examples/example.c

136 lines
3.4 KiB
C

/*
How to use MuPDF to render a single page and print the result as
a PPM to stdout.
To build this example in a source tree and render first page at
100% zoom with no rotation, run:
make examples
./build/debug/example document.pdf 1 100 0 > page1.ppm
To build from installed sources, and render the same document, run:
gcc -I/usr/local/include -o example \
/usr/local/share/doc/mupdf/examples/example.c \
/usr/local/lib/libmupdf.a \
/usr/local/lib/libmupdfthird.a \
-lm
./example document.pdf 1 100 0 > page1.ppm
*/
#include <mupdf/fitz.h>
#include <stdio.h>
#include <stdlib.h>
int main(int argc, char **argv)
{
char *input;
float zoom, rotate;
int page_number, page_count;
fz_context *ctx;
fz_document *doc;
fz_pixmap *pix;
fz_matrix ctm;
int x, y;
if (argc < 3)
{
fprintf(stderr, "usage: example input-file page-number [ zoom [ rotate ] ]\n");
fprintf(stderr, "\tinput-file: path of PDF, XPS, CBZ or EPUB document to open\n");
fprintf(stderr, "\tPage numbering starts from one.\n");
fprintf(stderr, "\tZoom level is in percent (100 percent is 72 dpi).\n");
fprintf(stderr, "\tRotation is in degrees clockwise.\n");
return EXIT_FAILURE;
}
input = argv[1];
page_number = atoi(argv[2]) - 1;
zoom = argc > 3 ? atof(argv[3]) : 100;
rotate = argc > 4 ? atof(argv[4]) : 0;
/* Create a context to hold the exception stack and various caches. */
ctx = fz_new_context(NULL, NULL, FZ_STORE_UNLIMITED);
if (!ctx)
{
fprintf(stderr, "cannot create mupdf context\n");
return EXIT_FAILURE;
}
/* Register the default file types to handle. */
fz_try(ctx)
fz_register_document_handlers(ctx);
fz_catch(ctx)
{
fprintf(stderr, "cannot register document handlers: %s\n", fz_caught_message(ctx));
fz_drop_context(ctx);
return EXIT_FAILURE;
}
/* Open the document. */
fz_try(ctx)
doc = fz_open_document(ctx, input);
fz_catch(ctx)
{
fprintf(stderr, "cannot open document: %s\n", fz_caught_message(ctx));
fz_drop_context(ctx);
return EXIT_FAILURE;
}
/* Count the number of pages. */
fz_try(ctx)
page_count = fz_count_pages(ctx, doc);
fz_catch(ctx)
{
fprintf(stderr, "cannot count number of pages: %s\n", fz_caught_message(ctx));
fz_drop_document(ctx, doc);
fz_drop_context(ctx);
return EXIT_FAILURE;
}
if (page_number < 0 || page_number >= page_count)
{
fprintf(stderr, "page number out of range: %d (page count %d)\n", page_number + 1, page_count);
fz_drop_document(ctx, doc);
fz_drop_context(ctx);
return EXIT_FAILURE;
}
/* Compute a transformation matrix for the zoom and rotation desired. */
/* The default resolution without scaling is 72 dpi. */
ctm = fz_scale(zoom / 100, zoom / 100);
ctm = fz_pre_rotate(ctm, rotate);
/* Render page to an RGB pixmap. */
fz_try(ctx)
pix = fz_new_pixmap_from_page_number(ctx, doc, page_number, ctm, fz_device_rgb(ctx), NULL, 0);
fz_catch(ctx)
{
fprintf(stderr, "cannot render page: %s\n", fz_caught_message(ctx));
fz_drop_document(ctx, doc);
fz_drop_context(ctx);
return EXIT_FAILURE;
}
/* Print image data in ascii PPM format. */
printf("P3\n");
printf("%d %d\n", pix->w, pix->h);
printf("255\n");
for (y = 0; y < pix->h; ++y)
{
unsigned char *p = &pix->samples[y * pix->stride];
for (x = 0; x < pix->w; ++x)
{
if (x > 0)
printf(" ");
printf("%3d %3d %3d", p[0], p[1], p[2]);
p += pix->n;
}
printf("\n");
}
/* Clean up. */
fz_drop_pixmap(ctx, pix);
fz_drop_document(ctx, doc);
fz_drop_context(ctx);
return EXIT_SUCCESS;
}