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 "image-load-djvu.h"
  22
  23 #include <config.h>
  24
  25 #if HAVE_DJVU
  26
  27 #include <cairo.h>
  28 #include <gdk-pixbuf/gdk-pixbuf.h>
  29 #include <glib-object.h>
  30 #include <glib.h>
  31 #include <libdjvu/ddjvuapi.h>
  32
  33 #include "image-load.h"
  34
  35 struct ImageLoaderDJVU {
  36         ImageLoaderBackendCbAreaUpdated area_updated_cb;
  37         ImageLoaderBackendCbSize size_cb;
  38         ImageLoaderBackendCbAreaPrepared area_prepared_cb;
  39         gpointer data;
  40         GdkPixbuf *pixbuf;
  41         guint requested_width;
  42         guint requested_height;
  43         gboolean abort;
  44         gint page_num;
  45         gint page_total;
  46 };
  47
  48 static void free_buffer(guchar *pixels, gpointer)
  49 {
  50         g_free (pixels);;
  51 }
  52
  53 static gboolean image_loader_djvu_load(gpointer loader, const guchar *buf, gsize count, GError **)
  54 {
  55         auto ld = static_cast<ImageLoaderDJVU *>(loader);
  56         ddjvu_context_t *ctx;
  57         ddjvu_document_t *doc;
  58         ddjvu_page_t *page;
  59         ddjvu_rect_t rrect;
  60         ddjvu_rect_t prect;
  61         ddjvu_format_t *fmt;
  62         gint width;
  63         gint height;
  64         gint stride;
  65         gboolean alpha = FALSE;
  66         cairo_surface_t *surface;
  67         guchar *pixels;
  68
  69         ctx = ddjvu_context_create(nullptr);
  70
  71         doc = ddjvu_document_create(ctx, nullptr, FALSE);
  72
  73         ddjvu_stream_write(doc, 0, reinterpret_cast<const char *>(buf), count );
  74         while (!ddjvu_document_decoding_done(doc));
  75
  76         ld->page_total = ddjvu_document_get_pagenum(doc);
  77
  78         page = ddjvu_page_create_by_pageno(doc, ld->page_num);
  79         while (!ddjvu_page_decoding_done(page));
  80
  81         fmt = ddjvu_format_create(DDJVU_FORMAT_RGB24, 0, nullptr);
  82
  83         width = ddjvu_page_get_width(page);
  84         height = ddjvu_page_get_height(page);
  85         stride = width * 4;
  86
  87         pixels = static_cast<guchar *>(g_malloc(height * stride));
  88
  89         prect.x = 0;
  90         prect.y = 0;
  91         prect.w = width;
  92         prect.h = height;
  93         rrect = prect;
  94
  95         surface = cairo_image_surface_create_for_data(pixels, CAIRO_FORMAT_RGB24, width, height, stride);
  96
  97         ddjvu_page_render(page, DDJVU_RENDER_COLOR, &prect, &rrect, fmt, stride, reinterpret_cast<char *>(pixels));
  98
  99         /**
 100          * @FIXME implementation of rotation is not correct */
 101         GdkPixbuf *tmp1;
 102         GdkPixbuf *tmp2;
 103         tmp1 = gdk_pixbuf_new_from_data(pixels, GDK_COLORSPACE_RGB, alpha, 8, width, height, stride, free_buffer, nullptr);
 104         tmp2 = gdk_pixbuf_flip(tmp1, TRUE);
 105         g_object_unref(tmp1);
 106
 107         ld->pixbuf = gdk_pixbuf_rotate_simple(tmp2,GDK_PIXBUF_ROTATE_UPSIDEDOWN);
 108
 109         ld->area_updated_cb(loader, 0, 0, width, height, ld->data);
 110
 111
 112         cairo_surface_destroy(surface);
 113         ddjvu_page_release(page);
 114         ddjvu_document_release(doc);
 115         ddjvu_context_release(ctx);
 116
 117         return TRUE;
 118 }
 119
 120 static gpointer image_loader_djvu_new(ImageLoaderBackendCbAreaUpdated area_updated_cb, ImageLoaderBackendCbSize size_cb, ImageLoaderBackendCbAreaPrepared area_prepared_cb, gpointer data)
 121 {
 122         auto loader = g_new0(ImageLoaderDJVU, 1);
 123         loader->area_updated_cb = area_updated_cb;
 124         loader->size_cb = size_cb;
 125         loader->area_prepared_cb = area_prepared_cb;
 126         loader->data = data;
 127         return loader;
 128 }
 129
 130 static void image_loader_djvu_set_size(gpointer loader, int width, int height)
 131 {
 132         auto ld = static_cast<ImageLoaderDJVU *>(loader);
 133         ld->requested_width = width;
 134         ld->requested_height = height;
 135 }
 136
 137 static GdkPixbuf* image_loader_djvu_get_pixbuf(gpointer loader)
 138 {
 139         auto ld = static_cast<ImageLoaderDJVU *>(loader);
 140         return ld->pixbuf;
 141 }
 142
 143 static gchar* image_loader_djvu_get_format_name(gpointer)
 144 {
 145         return g_strdup("djvu");
 146 }
 147
 148 static gchar** image_loader_djvu_get_format_mime_types(gpointer)
 149 {
 150         static const gchar *mime[] = {"image/vnd.djvu", nullptr};
 151         return g_strdupv(const_cast<gchar **>(mime));
 152 }
 153
 154 static void image_loader_djvu_set_page_num(gpointer loader, gint page_num)
 155 {
 156         auto ld = static_cast<ImageLoaderDJVU *>(loader);
 157
 158         ld->page_num = page_num;
 159 }
 160
 161 static gint image_loader_djvu_get_page_total(gpointer loader)
 162 {
 163         auto ld = static_cast<ImageLoaderDJVU *>(loader);
 164
 165         return ld->page_total;
 166 }
 167
 168 static gboolean image_loader_djvu_close(gpointer, GError **)
 169 {
 170         return TRUE;
 171 }
 172
 173 static void image_loader_djvu_abort(gpointer loader)
 174 {
 175         auto ld = static_cast<ImageLoaderDJVU *>(loader);
 176         ld->abort = TRUE;
 177 }
 178
 179 static void image_loader_djvu_free(gpointer loader)
 180 {
 181         auto ld = static_cast<ImageLoaderDJVU *>(loader);
 182         if (ld->pixbuf) g_object_unref(ld->pixbuf);
 183         g_free(ld);
 184 }
 185
 186 void image_loader_backend_set_djvu(ImageLoaderBackend *funcs)
 187 {
 188         funcs->loader_new = image_loader_djvu_new;
 189         funcs->set_size = image_loader_djvu_set_size;
 190         funcs->load = image_loader_djvu_load;
 191         funcs->write = nullptr;
 192         funcs->get_pixbuf = image_loader_djvu_get_pixbuf;
 193         funcs->close = image_loader_djvu_close;
 194         funcs->abort = image_loader_djvu_abort;
 195         funcs->free = image_loader_djvu_free;
 196         funcs->get_format_name = image_loader_djvu_get_format_name;
 197         funcs->get_format_mime_types = image_loader_djvu_get_format_mime_types;
 198         funcs->set_page_num = image_loader_djvu_set_page_num;
 199         funcs->get_page_total = image_loader_djvu_get_page_total;
 200 }
 201
 202 #endif
 203 /* vim: set shiftwidth=8 softtabstop=0 cindent cinoptions={1s: */