diff options
Diffstat (limited to 'libs/cairo-1.16.0/src/cairo-image-info.c')
| -rw-r--r-- | libs/cairo-1.16.0/src/cairo-image-info.c | 421 |
1 files changed, 421 insertions, 0 deletions
diff --git a/libs/cairo-1.16.0/src/cairo-image-info.c b/libs/cairo-1.16.0/src/cairo-image-info.c new file mode 100644 index 0000000..d147e37 --- /dev/null +++ b/libs/cairo-1.16.0/src/cairo-image-info.c @@ -0,0 +1,421 @@ +/* -*- Mode: c; tab-width: 8; c-basic-offset: 4; indent-tabs-mode: t; -*- */ +/* cairo - a vector graphics library with display and print output + * + * Copyright © 2008 Adrian Johnson + * + * This library is free software; you can redistribute it and/or + * modify it either under the terms of the GNU Lesser General Public + * License version 2.1 as published by the Free Software Foundation + * (the "LGPL") or, at your option, under the terms of the Mozilla + * Public License Version 1.1 (the "MPL"). If you do not alter this + * notice, a recipient may use your version of this file under either + * the MPL or the LGPL. + * + * You should have received a copy of the LGPL along with this library + * in the file COPYING-LGPL-2.1; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA + * You should have received a copy of the MPL along with this library + * in the file COPYING-MPL-1.1 + * + * The contents of this file are subject to the Mozilla Public License + * Version 1.1 (the "License"); you may not use this file except in + * compliance with the License. You may obtain a copy of the License at + * http://www.mozilla.org/MPL/ + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY + * OF ANY KIND, either express or implied. See the LGPL or the MPL for + * the specific language governing rights and limitations. + * + * The Original Code is the cairo graphics library. + * + * The Initial Developer of the Original Code is Adrian Johnson. + * + * Contributor(s): + * Adrian Johnson <ajohnson@redneon.com> + */ + +#include "cairoint.h" + +#include "cairo-error-private.h" +#include "cairo-image-info-private.h" + +/* JPEG (image/jpeg) + * + * http://www.w3.org/Graphics/JPEG/itu-t81.pdf + */ + +/* Markers with no parameters. All other markers are followed by a two + * byte length of the parameters. */ +#define TEM 0x01 +#define RST_begin 0xd0 +#define RST_end 0xd7 +#define SOI 0xd8 +#define EOI 0xd9 + +/* Start of frame markers. */ +#define SOF0 0xc0 +#define SOF1 0xc1 +#define SOF2 0xc2 +#define SOF3 0xc3 +#define SOF5 0xc5 +#define SOF6 0xc6 +#define SOF7 0xc7 +#define SOF9 0xc9 +#define SOF10 0xca +#define SOF11 0xcb +#define SOF13 0xcd +#define SOF14 0xce +#define SOF15 0xcf + +static const unsigned char * +_jpeg_skip_segment (const unsigned char *p) +{ + int len; + + p++; + len = (p[0] << 8) | p[1]; + + return p + len; +} + +static void +_jpeg_extract_info (cairo_image_info_t *info, const unsigned char *p) +{ + info->width = (p[6] << 8) + p[7]; + info->height = (p[4] << 8) + p[5]; + info->num_components = p[8]; + info->bits_per_component = p[3]; +} + +cairo_int_status_t +_cairo_image_info_get_jpeg_info (cairo_image_info_t *info, + const unsigned char *data, + long length) +{ + const unsigned char *p = data; + + while (p + 1 < data + length) { + if (*p != 0xff) + return CAIRO_INT_STATUS_UNSUPPORTED; + p++; + + switch (*p) { + /* skip fill bytes */ + case 0xff: + p++; + break; + + case TEM: + case SOI: + case EOI: + p++; + break; + + case SOF0: + case SOF1: + case SOF2: + case SOF3: + case SOF5: + case SOF6: + case SOF7: + case SOF9: + case SOF10: + case SOF11: + case SOF13: + case SOF14: + case SOF15: + /* Start of frame found. Extract the image parameters. */ + if (p + 8 > data + length) + return CAIRO_INT_STATUS_UNSUPPORTED; + + _jpeg_extract_info (info, p); + return CAIRO_STATUS_SUCCESS; + + default: + if (*p >= RST_begin && *p <= RST_end) { + p++; + break; + } + + if (p + 3 > data + length) + return CAIRO_INT_STATUS_UNSUPPORTED; + + p = _jpeg_skip_segment (p); + break; + } + } + + return CAIRO_STATUS_SUCCESS; +} + +/* JPEG 2000 (image/jp2) + * + * http://www.jpeg.org/public/15444-1annexi.pdf + */ + +#define JPX_FILETYPE 0x66747970 +#define JPX_JP2_HEADER 0x6A703268 +#define JPX_IMAGE_HEADER 0x69686472 + +static const unsigned char _jpx_signature[] = { + 0x00, 0x00, 0x00, 0x0c, 0x6a, 0x50, 0x20, 0x20, 0x0d, 0x0a, 0x87, 0x0a +}; + +static const unsigned char * +_jpx_next_box (const unsigned char *p) +{ + return p + get_unaligned_be32 (p); +} + +static const unsigned char * +_jpx_get_box_contents (const unsigned char *p) +{ + return p + 8; +} + +static cairo_bool_t +_jpx_match_box (const unsigned char *p, const unsigned char *end, uint32_t type) +{ + uint32_t length; + + if (p + 8 < end) { + length = get_unaligned_be32 (p); + if (get_unaligned_be32 (p + 4) == type && p + length < end) + return TRUE; + } + + return FALSE; +} + +static const unsigned char * +_jpx_find_box (const unsigned char *p, const unsigned char *end, uint32_t type) +{ + while (p < end) { + if (_jpx_match_box (p, end, type)) + return p; + p = _jpx_next_box (p); + } + + return NULL; +} + +static void +_jpx_extract_info (const unsigned char *p, cairo_image_info_t *info) +{ + info->height = get_unaligned_be32 (p); + info->width = get_unaligned_be32 (p + 4); + info->num_components = (p[8] << 8) + p[9]; + info->bits_per_component = p[10]; +} + +cairo_int_status_t +_cairo_image_info_get_jpx_info (cairo_image_info_t *info, + const unsigned char *data, + unsigned long length) +{ + const unsigned char *p = data; + const unsigned char *end = data + length; + + /* First 12 bytes must be the JPEG 2000 signature box. */ + if (length < ARRAY_LENGTH(_jpx_signature) || + memcmp(p, _jpx_signature, ARRAY_LENGTH(_jpx_signature)) != 0) + return CAIRO_INT_STATUS_UNSUPPORTED; + + p += ARRAY_LENGTH(_jpx_signature); + + /* Next box must be a File Type Box */ + if (! _jpx_match_box (p, end, JPX_FILETYPE)) + return CAIRO_INT_STATUS_UNSUPPORTED; + + p = _jpx_next_box (p); + + /* Locate the JP2 header box. */ + p = _jpx_find_box (p, end, JPX_JP2_HEADER); + if (!p) + return CAIRO_INT_STATUS_UNSUPPORTED; + + /* Step into the JP2 header box. First box must be the Image + * Header */ + p = _jpx_get_box_contents (p); + if (! _jpx_match_box (p, end, JPX_IMAGE_HEADER)) + return CAIRO_INT_STATUS_UNSUPPORTED; + + /* Get the image info */ + p = _jpx_get_box_contents (p); + _jpx_extract_info (p, info); + + return CAIRO_STATUS_SUCCESS; +} + +/* PNG (image/png) + * + * http://www.w3.org/TR/2003/REC-PNG-20031110/ + */ + +#define PNG_IHDR 0x49484452 + +static const unsigned char _png_magic[8] = { 137, 80, 78, 71, 13, 10, 26, 10 }; + +cairo_int_status_t +_cairo_image_info_get_png_info (cairo_image_info_t *info, + const unsigned char *data, + unsigned long length) +{ + const unsigned char *p = data; + const unsigned char *end = data + length; + + if (length < 8 || memcmp (data, _png_magic, 8) != 0) + return CAIRO_INT_STATUS_UNSUPPORTED; + + p += 8; + + /* The first chunk must be IDHR. IDHR has 13 bytes of data plus + * the 12 bytes of overhead for the chunk. */ + if (p + 13 + 12 > end) + return CAIRO_INT_STATUS_UNSUPPORTED; + + p += 4; + if (get_unaligned_be32 (p) != PNG_IHDR) + return CAIRO_INT_STATUS_UNSUPPORTED; + + p += 4; + info->width = get_unaligned_be32 (p); + p += 4; + info->height = get_unaligned_be32 (p); + + return CAIRO_STATUS_SUCCESS; +} + +static const unsigned char * +_jbig2_find_data_end (const unsigned char *p, + const unsigned char *end, + int type) +{ + unsigned char end_seq[2]; + int mmr; + + /* Segments of type "Immediate generic region" may have an + * unspecified data length. The JBIG2 specification specifies the + * method to find the end of the data for these segments. */ + if (type == 36 || type == 38 || type == 39) { + if (p + 18 < end) { + mmr = p[17] & 0x01; + if (mmr) { + /* MMR encoding ends with 0x00, 0x00 */ + end_seq[0] = 0x00; + end_seq[1] = 0x00; + } else { + /* Template encoding ends with 0xff, 0xac */ + end_seq[0] = 0xff; + end_seq[1] = 0xac; + } + p += 18; + while (p < end) { + if (p[0] == end_seq[0] && p[1] == end_seq[1]) { + /* Skip the 2 terminating bytes and the 4 byte row count that follows. */ + p += 6; + if (p < end) + return p; + } + p++; + } + } + } + + return NULL; +} + +static const unsigned char * +_jbig2_get_next_segment (const unsigned char *p, + const unsigned char *end, + int *type, + const unsigned char **data, + unsigned long *data_len) +{ + unsigned long seg_num; + cairo_bool_t big_page_size; + int num_segs; + int ref_seg_bytes; + int referred_size; + + if (p + 6 >= end) + return NULL; + + seg_num = get_unaligned_be32 (p); + *type = p[4] & 0x3f; + big_page_size = (p[4] & 0x40) != 0; + p += 5; + + num_segs = p[0] >> 5; + if (num_segs == 7) { + num_segs = get_unaligned_be32 (p) & 0x1fffffff; + ref_seg_bytes = 4 + ((num_segs + 1)/8); + } else { + ref_seg_bytes = 1; + } + p += ref_seg_bytes; + + if (seg_num <= 256) + referred_size = 1; + else if (seg_num <= 65536) + referred_size = 2; + else + referred_size = 4; + + p += num_segs * referred_size; + p += big_page_size ? 4 : 1; + if (p + 4 >= end) + return NULL; + + *data_len = get_unaligned_be32 (p); + p += 4; + *data = p; + + if (*data_len == 0xffffffff) { + /* if data length is -1 we have to scan through the data to find the end */ + p = _jbig2_find_data_end (*data, end, *type); + if (!p || p >= end) + return NULL; + + *data_len = p - *data; + } else { + p += *data_len; + } + + if (p < end) + return p; + else + return NULL; +} + +static void +_jbig2_extract_info (cairo_image_info_t *info, const unsigned char *p) +{ + info->width = get_unaligned_be32 (p); + info->height = get_unaligned_be32 (p + 4); + info->num_components = 1; + info->bits_per_component = 1; +} + +cairo_int_status_t +_cairo_image_info_get_jbig2_info (cairo_image_info_t *info, + const unsigned char *data, + unsigned long length) +{ + const unsigned char *p = data; + const unsigned char *end = data + length; + int seg_type; + const unsigned char *seg_data; + unsigned long seg_data_len; + + while (p && p < end) { + p = _jbig2_get_next_segment (p, end, &seg_type, &seg_data, &seg_data_len); + if (p && seg_type == 48 && seg_data_len > 8) { + /* page information segment */ + _jbig2_extract_info (info, seg_data); + return CAIRO_STATUS_SUCCESS; + } + } + + return CAIRO_INT_STATUS_UNSUPPORTED; +} |