djvulibre.c

   1 #include <stdlib.h>
   2 #include <string.h>
   3 #include <libdjvu/ddjvuapi.h>
   4 #include "draw.h"
   5 #include "doc.h"
   6
   7 #define MIN(a, b)       ((a) < (b) ? (a) : (b))
   8
   9 struct doc {
  10         ddjvu_context_t *ctx;
  11         ddjvu_document_t *doc;
  12 };
  13
  14 int djvu_handle(struct doc *doc)
  15 {
  16         ddjvu_message_t *msg;
  17         msg = ddjvu_message_wait(doc->ctx);
  18         while ((msg = ddjvu_message_peek(doc->ctx))) {
  19                 if (msg->m_any.tag == DDJVU_ERROR) {
  20                         fprintf(stderr,"ddjvu: %s\n", msg->m_error.message);
  21                         return 1;
  22                 }
  23                 ddjvu_message_pop(doc->ctx);
  24         }
  25         return 0;
  26 }
  27
  28 static void djvu_render(ddjvu_page_t *page, int mode, void *bitmap, int cols,
  29                 ddjvu_rect_t *prect, ddjvu_rect_t *rrect)
  30 {
  31         ddjvu_format_t *fmt;
  32         fmt = ddjvu_format_create(DDJVU_FORMAT_GREY8, 0, 0);
  33         ddjvu_format_set_row_order(fmt, 1);
  34
  35         ddjvu_page_render(page, mode, prect, rrect, fmt, cols, bitmap);
  36         ddjvu_format_release(fmt);
  37 }
  38
  39 #define SIZE            (1 << 13)
  40 static char img[SIZE * SIZE];
  41
  42 int doc_draw(struct doc *doc, fbval_t *bitmap, int p, int rows, int cols,
  43                 int zoom, int rotate)
  44 {
  45         ddjvu_page_t *page;
  46         ddjvu_rect_t rect;
  47         ddjvu_pageinfo_t info;
  48         int iw, ih;
  49         int i, j;
  50         page = ddjvu_page_create_by_pageno(doc->doc, p - 1);
  51         if (!page)
  52                 return -1;
  53         if (!ddjvu_page_decoding_done(page))
  54                 if (djvu_handle(doc))
  55                         return -1;
  56
  57         ddjvu_document_get_pageinfo(doc->doc, p - 1, &info);
  58         iw = ddjvu_page_get_width(page);
  59         ih = ddjvu_page_get_height(page);
  60         rect.x = 0;
  61         rect.y = 0;
  62         rect.w = iw;
  63         rect.h = ih;
  64
  65         /* mode: DDJVU_RENDER_(BLACK|COLOR|BACKGROUND|FOREGROUND) */
  66         djvu_render(page, DDJVU_RENDER_FOREGROUND, img, SIZE, &rect, &rect);
  67         ddjvu_page_release(page);
  68         zoom /= 4;
  69         for (i = 0; i < ih * zoom / 10; i++)
  70                 for (j = 0; j < iw * zoom / 10; j++)
  71                         bitmap[i * cols + j] = img[i * 10 / zoom * SIZE + j * 10 / zoom];
  72         return 0;
  73 }
  74
  75 int doc_pages(struct doc *doc)
  76 {
  77         return ddjvu_document_get_pagenum(doc->doc);
  78 }
  79
  80 struct doc *doc_open(char *path)
  81 {
  82         struct doc *doc = malloc(sizeof(*doc));
  83         doc->ctx = ddjvu_context_create("fbpdf");
  84         if (!doc->ctx)
  85                 goto fail;
  86         doc->doc = ddjvu_document_create_by_filename(doc->ctx, path, 1);
  87         if (!doc->doc)
  88                 goto fail;
  89         if (!ddjvu_document_decoding_done(doc->doc))
  90                 if (djvu_handle(doc))
  91                         goto fail;
  92         return doc;
  93 fail:
  94         doc_close(doc);
  95         return NULL;
  96 }
  97
  98 void doc_close(struct doc *doc)
  99 {
 100         if (doc->doc)
 101                 ddjvu_context_release(doc->ctx);
 102         if (doc->ctx)
 103                 ddjvu_document_release(doc->doc);
 104         free(doc);
 105 }