src/image-load-djvu.cc

   1 /*
   2  * Copyright (C) 20019 - The Geeqie Team
   3  *
   4  * Author: Colin Clark
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  */
  20
  21 #include "main.h"
  22
  23 #include "image-load.h"
  24 #include "image-load-djvu.h"
  25
  26 #ifdef HAVE_DJVU
  27
  28 #include <libdjvu/ddjvuapi.h>
  29 #include <libdjvu/miniexp.h>
  30
  31 struct ImageLoaderDJVU {
  32         ImageLoaderBackendCbAreaUpdated area_updated_cb;
  33         ImageLoaderBackendCbSize size_cb;
  34         ImageLoaderBackendCbAreaPrepared area_prepared_cb;
  35         gpointer data;
  36         GdkPixbuf *pixbuf;
  37         guint requested_width;
  38         guint requested_height;
  39         gboolean abort;
  40         gint page_num;
  41         gint page_total;
  42 };
  43
  44 static void free_buffer(guchar *pixels, gpointer)
  45 {
  46         g_free (pixels);;
  47 }
  48
  49 static gboolean image_loader_djvu_load(gpointer loader, const guchar *buf, gsize count, GError **)
  50 {
  51         auto ld = static_cast<ImageLoaderDJVU *>(loader);
  52         ddjvu_context_t *ctx;
  53         ddjvu_document_t *doc;
  54         ddjvu_page_t *page;
  55         ddjvu_rect_t rrect;
  56         ddjvu_rect_t prect;
  57         ddjvu_format_t *fmt;
  58         gint width, height;
  59         gint stride;
  60         gboolean alpha = FALSE;
  61         cairo_surface_t *surface;
  62         guchar *pixels;
  63
  64         ctx = ddjvu_context_create(nullptr);
  65
  66         doc = ddjvu_document_create(ctx, nullptr, FALSE);
  67
  68         ddjvu_stream_write(doc, 0, reinterpret_cast<const char *>(buf), count );
  69         while (!ddjvu_document_decoding_done(doc));
  70
  71         ld->page_total = ddjvu_document_get_pagenum(doc);
  72
  73         page = ddjvu_page_create_by_pageno(doc, ld->page_num);
  74         while (!ddjvu_page_decoding_done(page));
  75
  76         fmt = ddjvu_format_create(DDJVU_FORMAT_RGB24, 0, nullptr);
  77
  78         width = ddjvu_page_get_width(page);
  79         height = ddjvu_page_get_height(page);
  80         stride = width * 4;
  81
  82         pixels = static_cast<guchar *>(g_malloc(height * stride));
  83
  84         prect.x = 0;
  85         prect.y = 0;
  86         prect.w = width;
  87         prect.h = height;
  88         rrect = prect;
  89
  90         surface = cairo_image_surface_create_for_data(pixels, CAIRO_FORMAT_RGB24, width, height, stride);
  91
  92         ddjvu_page_render(page, DDJVU_RENDER_COLOR, &prect, &rrect, fmt, stride, reinterpret_cast<char *>(pixels));
  93
  94         /**
  95          * @FIXME implementation of rotation is not correct */
  96         GdkPixbuf *tmp1;
  97         GdkPixbuf *tmp2;
  98         tmp1 = gdk_pixbuf_new_from_data(pixels, GDK_COLORSPACE_RGB, alpha, 8, width, height, stride, free_buffer, nullptr);
  99         tmp2 = gdk_pixbuf_flip(tmp1, TRUE);
 100         g_object_unref(tmp1);
 101
 102         ld->pixbuf = gdk_pixbuf_rotate_simple(tmp2,GDK_PIXBUF_ROTATE_UPSIDEDOWN);
 103
 104         ld->area_updated_cb(loader, 0, 0, width, height, ld->data);
 105
 106
 107         cairo_surface_destroy(surface);
 108         ddjvu_page_release(page);
 109         ddjvu_document_release(doc);
 110         ddjvu_context_release(ctx);
 111
 112         return TRUE;
 113 }
 114
 115 static gpointer image_loader_djvu_new(ImageLoaderBackendCbAreaUpdated area_updated_cb, ImageLoaderBackendCbSize size_cb, ImageLoaderBackendCbAreaPrepared area_prepared_cb, gpointer data)
 116 {
 117         auto loader = g_new0(ImageLoaderDJVU, 1);
 118         loader->area_updated_cb = area_updated_cb;
 119         loader->size_cb = size_cb;
 120         loader->area_prepared_cb = area_prepared_cb;
 121         loader->data = data;
 122         return loader;
 123 }
 124
 125 static void image_loader_djvu_set_size(gpointer loader, int width, int height)
 126 {
 127         auto ld = static_cast<ImageLoaderDJVU *>(loader);
 128         ld->requested_width = width;
 129         ld->requested_height = height;
 130 }
 131
 132 static GdkPixbuf* image_loader_djvu_get_pixbuf(gpointer loader)
 133 {
 134         auto ld = static_cast<ImageLoaderDJVU *>(loader);
 135         return ld->pixbuf;
 136 }
 137
 138 static gchar* image_loader_djvu_get_format_name(gpointer)
 139 {
 140         return g_strdup("djvu");
 141 }
 142
 143 static gchar** image_loader_djvu_get_format_mime_types(gpointer)
 144 {
 145         static const gchar *mime[] = {"image/vnd.djvu", nullptr};
 146         return g_strdupv(const_cast<gchar **>(mime));
 147 }
 148
 149 static void image_loader_djvu_set_page_num(gpointer loader, gint page_num)
 150 {
 151         auto ld = static_cast<ImageLoaderDJVU *>(loader);
 152
 153         ld->page_num = page_num;
 154 }
 155
 156 static gint image_loader_djvu_get_page_total(gpointer loader)
 157 {
 158         auto ld = static_cast<ImageLoaderDJVU *>(loader);
 159
 160         return ld->page_total;
 161 }
 162
 163 static gboolean image_loader_djvu_close(gpointer, GError **)
 164 {
 165         return TRUE;
 166 }
 167
 168 static void image_loader_djvu_abort(gpointer loader)
 169 {
 170         auto ld = static_cast<ImageLoaderDJVU *>(loader);
 171         ld->abort = TRUE;
 172 }
 173
 174 static void image_loader_djvu_free(gpointer loader)
 175 {
 176         auto ld = static_cast<ImageLoaderDJVU *>(loader);
 177         if (ld->pixbuf) g_object_unref(ld->pixbuf);
 178         g_free(ld);
 179 }
 180
 181 void image_loader_backend_set_djvu(ImageLoaderBackend *funcs)
 182 {
 183         funcs->loader_new = image_loader_djvu_new;
 184         funcs->set_size = image_loader_djvu_set_size;
 185         funcs->load = image_loader_djvu_load;
 186         funcs->write = nullptr;
 187         funcs->get_pixbuf = image_loader_djvu_get_pixbuf;
 188         funcs->close = image_loader_djvu_close;
 189         funcs->abort = image_loader_djvu_abort;
 190         funcs->free = image_loader_djvu_free;
 191         funcs->get_format_name = image_loader_djvu_get_format_name;
 192         funcs->get_format_mime_types = image_loader_djvu_get_format_mime_types;
 193         funcs->set_page_num = image_loader_djvu_set_page_num;
 194         funcs->get_page_total = image_loader_djvu_get_page_total;
 195 }
 196
 197 #endif
 198 /* vim: set shiftwidth=8 softtabstop=0 cindent cinoptions={1s: */