Go to most recent revision | Details | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 4680 | right-hear | 1 | #include "fitz.h" |
| 2 | #include "mupdf.h" |
||
| 3 | |||
| 4 | struct info |
||
| 5 | { |
||
| 6 | fz_obj *resources; |
||
| 7 | fz_obj *mediabox; |
||
| 8 | fz_obj *cropbox; |
||
| 9 | fz_obj *rotate; |
||
| 10 | }; |
||
| 11 | |||
| 12 | int |
||
| 13 | pdf_count_pages(pdf_xref *xref) |
||
| 14 | { |
||
| 15 | return xref->page_len; |
||
| 16 | } |
||
| 17 | |||
| 18 | int |
||
| 19 | pdf_find_page_number(pdf_xref *xref, fz_obj *page) |
||
| 20 | { |
||
| 21 | int i, num = fz_to_num(page); |
||
| 22 | for (i = 0; i < xref->page_len; i++) |
||
| 23 | if (num == fz_to_num(xref->page_refs[i])) |
||
| 24 | return i; |
||
| 25 | return -1; |
||
| 26 | } |
||
| 27 | |||
| 28 | static void |
||
| 29 | pdf_load_page_tree_node(pdf_xref *xref, fz_obj *node, struct info info) |
||
| 30 | { |
||
| 31 | fz_obj *dict, *kids, *count; |
||
| 32 | fz_obj *obj, *tmp; |
||
| 33 | int i, n; |
||
| 34 | |||
| 35 | /* prevent infinite recursion */ |
||
| 36 | if (fz_dict_gets(node, ".seen")) |
||
| 37 | return; |
||
| 38 | |||
| 39 | kids = fz_dict_gets(node, "Kids"); |
||
| 40 | count = fz_dict_gets(node, "Count"); |
||
| 41 | |||
| 42 | if (fz_is_array(kids) && fz_is_int(count)) |
||
| 43 | { |
||
| 44 | obj = fz_dict_gets(node, "Resources"); |
||
| 45 | if (obj) |
||
| 46 | info.resources = obj; |
||
| 47 | obj = fz_dict_gets(node, "MediaBox"); |
||
| 48 | if (obj) |
||
| 49 | info.mediabox = obj; |
||
| 50 | obj = fz_dict_gets(node, "CropBox"); |
||
| 51 | if (obj) |
||
| 52 | info.cropbox = obj; |
||
| 53 | obj = fz_dict_gets(node, "Rotate"); |
||
| 54 | if (obj) |
||
| 55 | info.rotate = obj; |
||
| 56 | |||
| 57 | tmp = fz_new_null(); |
||
| 58 | fz_dict_puts(node, ".seen", tmp); |
||
| 59 | fz_drop_obj(tmp); |
||
| 60 | |||
| 61 | n = fz_array_len(kids); |
||
| 62 | for (i = 0; i < n; i++) |
||
| 63 | { |
||
| 64 | obj = fz_array_get(kids, i); |
||
| 65 | pdf_load_page_tree_node(xref, obj, info); |
||
| 66 | } |
||
| 67 | |||
| 68 | fz_dict_dels(node, ".seen"); |
||
| 69 | } |
||
| 70 | else |
||
| 71 | { |
||
| 72 | dict = fz_resolve_indirect(node); |
||
| 73 | |||
| 74 | if (info.resources && !fz_dict_gets(dict, "Resources")) |
||
| 75 | fz_dict_puts(dict, "Resources", info.resources); |
||
| 76 | if (info.mediabox && !fz_dict_gets(dict, "MediaBox")) |
||
| 77 | fz_dict_puts(dict, "MediaBox", info.mediabox); |
||
| 78 | if (info.cropbox && !fz_dict_gets(dict, "CropBox")) |
||
| 79 | fz_dict_puts(dict, "CropBox", info.cropbox); |
||
| 80 | if (info.rotate && !fz_dict_gets(dict, "Rotate")) |
||
| 81 | fz_dict_puts(dict, "Rotate", info.rotate); |
||
| 82 | |||
| 83 | if (xref->page_len == xref->page_cap) |
||
| 84 | { |
||
| 85 | fz_warn("found more pages than expected"); |
||
| 86 | xref->page_cap ++; |
||
| 87 | xref->page_refs = fz_realloc(xref->page_refs, xref->page_cap, sizeof(fz_obj*)); |
||
| 88 | xref->page_objs = fz_realloc(xref->page_objs, xref->page_cap, sizeof(fz_obj*)); |
||
| 89 | } |
||
| 90 | |||
| 91 | xref->page_refs[xref->page_len] = fz_keep_obj(node); |
||
| 92 | xref->page_objs[xref->page_len] = fz_keep_obj(dict); |
||
| 93 | xref->page_len ++; |
||
| 94 | } |
||
| 95 | } |
||
| 96 | |||
| 97 | fz_error |
||
| 98 | pdf_load_page_tree(pdf_xref *xref) |
||
| 99 | { |
||
| 100 | struct info info; |
||
| 101 | fz_obj *catalog = fz_dict_gets(xref->trailer, "Root"); |
||
| 102 | fz_obj *pages = fz_dict_gets(catalog, "Pages"); |
||
| 103 | fz_obj *count = fz_dict_gets(pages, "Count"); |
||
| 104 | |||
| 105 | if (!fz_is_dict(pages)) |
||
| 106 | return fz_throw("missing page tree"); |
||
| 107 | if (!fz_is_int(count)) |
||
| 108 | return fz_throw("missing page count"); |
||
| 109 | |||
| 110 | xref->page_cap = fz_to_int(count); |
||
| 111 | xref->page_len = 0; |
||
| 112 | xref->page_refs = fz_calloc(xref->page_cap, sizeof(fz_obj*)); |
||
| 113 | xref->page_objs = fz_calloc(xref->page_cap, sizeof(fz_obj*)); |
||
| 114 | |||
| 115 | info.resources = NULL; |
||
| 116 | info.mediabox = NULL; |
||
| 117 | info.cropbox = NULL; |
||
| 118 | info.rotate = NULL; |
||
| 119 | |||
| 120 | pdf_load_page_tree_node(xref, pages, info); |
||
| 121 | |||
| 122 | return fz_okay; |
||
| 123 | } |
||
| 124 | |||
| 125 | /* We need to know whether to install a page-level transparency group */ |
||
| 126 | |||
| 127 | static int pdf_resources_use_blending(fz_obj *rdb); |
||
| 128 | |||
| 129 | static int |
||
| 130 | pdf_extgstate_uses_blending(fz_obj *dict) |
||
| 131 | { |
||
| 132 | fz_obj *obj = fz_dict_gets(dict, "BM"); |
||
| 133 | if (fz_is_name(obj) && strcmp(fz_to_name(obj), "Normal")) |
||
| 134 | return 1; |
||
| 135 | return 0; |
||
| 136 | } |
||
| 137 | |||
| 138 | static int |
||
| 139 | pdf_pattern_uses_blending(fz_obj *dict) |
||
| 140 | { |
||
| 141 | fz_obj *obj; |
||
| 142 | obj = fz_dict_gets(dict, "Resources"); |
||
| 143 | if (pdf_resources_use_blending(obj)) |
||
| 144 | return 1; |
||
| 145 | obj = fz_dict_gets(dict, "ExtGState"); |
||
| 146 | if (pdf_extgstate_uses_blending(obj)) |
||
| 147 | return 1; |
||
| 148 | return 0; |
||
| 149 | } |
||
| 150 | |||
| 151 | static int |
||
| 152 | pdf_xobject_uses_blending(fz_obj *dict) |
||
| 153 | { |
||
| 154 | fz_obj *obj = fz_dict_gets(dict, "Resources"); |
||
| 155 | if (pdf_resources_use_blending(obj)) |
||
| 156 | return 1; |
||
| 157 | return 0; |
||
| 158 | } |
||
| 159 | |||
| 160 | static int |
||
| 161 | pdf_resources_use_blending(fz_obj *rdb) |
||
| 162 | { |
||
| 163 | fz_obj *dict; |
||
| 164 | fz_obj *tmp; |
||
| 165 | int i; |
||
| 166 | |||
| 167 | if (!rdb) |
||
| 168 | return 0; |
||
| 169 | |||
| 170 | /* stop on cyclic resource dependencies */ |
||
| 171 | if (fz_dict_gets(rdb, ".useBM")) |
||
| 172 | return fz_to_bool(fz_dict_gets(rdb, ".useBM")); |
||
| 173 | |||
| 174 | tmp = fz_new_bool(0); |
||
| 175 | fz_dict_puts(rdb, ".useBM", tmp); |
||
| 176 | fz_drop_obj(tmp); |
||
| 177 | |||
| 178 | dict = fz_dict_gets(rdb, "ExtGState"); |
||
| 179 | for (i = 0; i < fz_dict_len(dict); i++) |
||
| 180 | if (pdf_extgstate_uses_blending(fz_dict_get_val(dict, i))) |
||
| 181 | goto found; |
||
| 182 | |||
| 183 | dict = fz_dict_gets(rdb, "Pattern"); |
||
| 184 | for (i = 0; i < fz_dict_len(dict); i++) |
||
| 185 | if (pdf_pattern_uses_blending(fz_dict_get_val(dict, i))) |
||
| 186 | goto found; |
||
| 187 | |||
| 188 | dict = fz_dict_gets(rdb, "XObject"); |
||
| 189 | for (i = 0; i < fz_dict_len(dict); i++) |
||
| 190 | if (pdf_xobject_uses_blending(fz_dict_get_val(dict, i))) |
||
| 191 | goto found; |
||
| 192 | |||
| 193 | return 0; |
||
| 194 | |||
| 195 | found: |
||
| 196 | tmp = fz_new_bool(1); |
||
| 197 | fz_dict_puts(rdb, ".useBM", tmp); |
||
| 198 | fz_drop_obj(tmp); |
||
| 199 | return 1; |
||
| 200 | } |
||
| 201 | |||
| 202 | /* we need to combine all sub-streams into one for the content stream interpreter */ |
||
| 203 | |||
| 204 | static fz_error |
||
| 205 | pdf_load_page_contents_array(fz_buffer **bigbufp, pdf_xref *xref, fz_obj *list) |
||
| 206 | { |
||
| 207 | fz_error error; |
||
| 208 | fz_buffer *big; |
||
| 209 | fz_buffer *one; |
||
| 210 | int i, n; |
||
| 211 | |||
| 212 | big = fz_new_buffer(32 * 1024); |
||
| 213 | |||
| 214 | n = fz_array_len(list); |
||
| 215 | for (i = 0; i < n; i++) |
||
| 216 | { |
||
| 217 | fz_obj *stm = fz_array_get(list, i); |
||
| 218 | error = pdf_load_stream(&one, xref, fz_to_num(stm), fz_to_gen(stm)); |
||
| 219 | if (error) |
||
| 220 | { |
||
| 221 | fz_catch(error, "cannot load content stream part %d/%d", i + 1, n); |
||
| 222 | continue; |
||
| 223 | } |
||
| 224 | |||
| 225 | if (big->len + one->len + 1 > big->cap) |
||
| 226 | fz_resize_buffer(big, big->len + one->len + 1); |
||
| 227 | memcpy(big->data + big->len, one->data, one->len); |
||
| 228 | big->data[big->len + one->len] = ' '; |
||
| 229 | big->len += one->len + 1; |
||
| 230 | |||
| 231 | fz_drop_buffer(one); |
||
| 232 | } |
||
| 233 | |||
| 234 | if (n > 0 && big->len == 0) |
||
| 235 | { |
||
| 236 | fz_drop_buffer(big); |
||
| 237 | return fz_throw("cannot load content stream"); |
||
| 238 | } |
||
| 239 | |||
| 240 | *bigbufp = big; |
||
| 241 | return fz_okay; |
||
| 242 | } |
||
| 243 | |||
| 244 | static fz_error |
||
| 245 | pdf_load_page_contents(fz_buffer **bufp, pdf_xref *xref, fz_obj *obj) |
||
| 246 | { |
||
| 247 | fz_error error; |
||
| 248 | |||
| 249 | if (fz_is_array(obj)) |
||
| 250 | { |
||
| 251 | error = pdf_load_page_contents_array(bufp, xref, obj); |
||
| 252 | if (error) |
||
| 253 | return fz_rethrow(error, "cannot load content stream array"); |
||
| 254 | } |
||
| 255 | else if (pdf_is_stream(xref, fz_to_num(obj), fz_to_gen(obj))) |
||
| 256 | { |
||
| 257 | error = pdf_load_stream(bufp, xref, fz_to_num(obj), fz_to_gen(obj)); |
||
| 258 | if (error) |
||
| 259 | return fz_rethrow(error, "cannot load content stream (%d 0 R)", fz_to_num(obj)); |
||
| 260 | } |
||
| 261 | else |
||
| 262 | { |
||
| 263 | fz_warn("page contents missing, leaving page blank"); |
||
| 264 | *bufp = fz_new_buffer(0); |
||
| 265 | } |
||
| 266 | |||
| 267 | return fz_okay; |
||
| 268 | } |
||
| 269 | |||
| 270 | fz_error |
||
| 271 | pdf_load_page(pdf_page **pagep, pdf_xref *xref, int number) |
||
| 272 | { |
||
| 273 | fz_error error; |
||
| 274 | pdf_page *page; |
||
| 275 | pdf_annot *annot; |
||
| 276 | fz_obj *pageobj, *pageref; |
||
| 277 | fz_obj *obj; |
||
| 278 | fz_bbox bbox; |
||
| 279 | |||
| 280 | if (number < 0 || number >= xref->page_len) |
||
| 281 | return fz_throw("cannot find page %d", number + 1); |
||
| 282 | |||
| 283 | /* Ensure that we have a store for resource objects */ |
||
| 284 | if (!xref->store) |
||
| 285 | xref->store = pdf_new_store(); |
||
| 286 | |||
| 287 | pageobj = xref->page_objs[number]; |
||
| 288 | pageref = xref->page_refs[number]; |
||
| 289 | |||
| 290 | page = fz_malloc(sizeof(pdf_page)); |
||
| 291 | page->resources = NULL; |
||
| 292 | page->contents = NULL; |
||
| 293 | page->transparency = 0; |
||
| 294 | page->links = NULL; |
||
| 295 | page->annots = NULL; |
||
| 296 | |||
| 297 | obj = fz_dict_gets(pageobj, "MediaBox"); |
||
| 298 | bbox = fz_round_rect(pdf_to_rect(obj)); |
||
| 299 | if (fz_is_empty_rect(pdf_to_rect(obj))) |
||
| 300 | { |
||
| 301 | fz_warn("cannot find page size for page %d", number + 1); |
||
| 302 | bbox.x0 = 0; |
||
| 303 | bbox.y0 = 0; |
||
| 304 | bbox.x1 = 612; |
||
| 305 | bbox.y1 = 792; |
||
| 306 | } |
||
| 307 | |||
| 308 | obj = fz_dict_gets(pageobj, "CropBox"); |
||
| 309 | if (fz_is_array(obj)) |
||
| 310 | { |
||
| 311 | fz_bbox cropbox = fz_round_rect(pdf_to_rect(obj)); |
||
| 312 | bbox = fz_intersect_bbox(bbox, cropbox); |
||
| 313 | } |
||
| 314 | |||
| 315 | page->mediabox.x0 = MIN(bbox.x0, bbox.x1); |
||
| 316 | page->mediabox.y0 = MIN(bbox.y0, bbox.y1); |
||
| 317 | page->mediabox.x1 = MAX(bbox.x0, bbox.x1); |
||
| 318 | page->mediabox.y1 = MAX(bbox.y0, bbox.y1); |
||
| 319 | |||
| 320 | if (page->mediabox.x1 - page->mediabox.x0 < 1 || page->mediabox.y1 - page->mediabox.y0 < 1) |
||
| 321 | { |
||
| 322 | fz_warn("invalid page size in page %d", number + 1); |
||
| 323 | page->mediabox = fz_unit_rect; |
||
| 324 | } |
||
| 325 | |||
| 326 | page->rotate = fz_to_int(fz_dict_gets(pageobj, "Rotate")); |
||
| 327 | |||
| 328 | obj = fz_dict_gets(pageobj, "Annots"); |
||
| 329 | if (obj) |
||
| 330 | { |
||
| 331 | pdf_load_links(&page->links, xref, obj); |
||
| 332 | pdf_load_annots(&page->annots, xref, obj); |
||
| 333 | } |
||
| 334 | |||
| 335 | page->resources = fz_dict_gets(pageobj, "Resources"); |
||
| 336 | if (page->resources) |
||
| 337 | fz_keep_obj(page->resources); |
||
| 338 | |||
| 339 | obj = fz_dict_gets(pageobj, "Contents"); |
||
| 340 | error = pdf_load_page_contents(&page->contents, xref, obj); |
||
| 341 | if (error) |
||
| 342 | { |
||
| 343 | pdf_free_page(page); |
||
| 344 | return fz_rethrow(error, "cannot load page %d contents (%d 0 R)", number + 1, fz_to_num(pageref)); |
||
| 345 | } |
||
| 346 | |||
| 347 | if (pdf_resources_use_blending(page->resources)) |
||
| 348 | page->transparency = 1; |
||
| 349 | |||
| 350 | for (annot = page->annots; annot && !page->transparency; annot = annot->next) |
||
| 351 | if (pdf_resources_use_blending(annot->ap->resources)) |
||
| 352 | page->transparency = 1; |
||
| 353 | |||
| 354 | *pagep = page; |
||
| 355 | return fz_okay; |
||
| 356 | } |
||
| 357 | |||
| 358 | void |
||
| 359 | pdf_free_page(pdf_page *page) |
||
| 360 | { |
||
| 361 | if (page->resources) |
||
| 362 | fz_drop_obj(page->resources); |
||
| 363 | if (page->contents) |
||
| 364 | fz_drop_buffer(page->contents); |
||
| 365 | if (page->links) |
||
| 366 | pdf_free_link(page->links); |
||
| 367 | if (page->annots) |
||
| 368 | pdf_free_annot(page->annots); |
||
| 369 | fz_free(page); |
||
| 370 | } |