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authorJonathan Kew <jfkthame@googlemail.com>2006-07-26 16:19:45 +0000
committerJonathan Kew <jfkthame@googlemail.com>2006-07-26 16:19:45 +0000
commit622bf4a7c90729be28a038c49e4c237ce9f31297 (patch)
tree77466d5c0a89c433bd1c08f4cbeaf410fda7b25c /Build/source/texk/web2c/xetexdir/pngimage.c
parente88aafe4ca4779a73487925dea63e8b55dc5e251 (diff)
added main xetex source directory
git-svn-id: svn://tug.org/texlive/trunk@1920 c570f23f-e606-0410-a88d-b1316a301751
Diffstat (limited to 'Build/source/texk/web2c/xetexdir/pngimage.c')
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1 files changed, 161 insertions, 0 deletions
diff --git a/Build/source/texk/web2c/xetexdir/pngimage.c b/Build/source/texk/web2c/xetexdir/pngimage.c
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index 00000000000..9408fbabc39
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+++ b/Build/source/texk/web2c/xetexdir/pngimage.c
@@ -0,0 +1,161 @@
+/****************************************************************************\
+ Part of the XeTeX typesetting system
+ copyright (c) 1994-2006 by SIL International
+ written by Jonathan Kew
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+\****************************************************************************/
+
+/* this file is derived from the dvipdfmx project;
+ the original header follows... */
+
+/* $Header: /home/cvsroot/dvipdfmx/src/pngimage.c,v 1.24 2004/09/11 14:50:29 hirata Exp $
+
+ This is dvipdfmx, an eXtended version of dvipdfm by Mark A. Wicks.
+
+ Copyright (C) 2002 by Jin-Hwan Cho and Shunsaku Hirata,
+ the dvipdfmx project team <dvipdfmx@project.ktug.or.kr>
+
+ Copyright (C) 1998, 1999 by Mark A. Wicks <mwicks@kettering.edu>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+*/
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+/*
+ * PNG SUPPORT
+ *
+ * All bitdepth less than 16 is supported.
+ * Supported color types are: PALETTE, RGB, GRAY, RGB_ALPHA, GRAY_ALPHA.
+ * Supported ancillary chunks: tRNS, cHRM + gAMA, (sRGB), (iCCP)
+ *
+ * gAMA support is available only when cHRM exists. cHRM support is not
+ * tested well. CalRGB/CalGray colorspace is used for PNG images that
+ * have cHRM chunk (but not sRGB).
+ *
+ * LIMITATIONS
+ *
+ * Recent version of PDF (>= 1.5) support 16 bpc, but 16 bit bitdepth PNG
+ * images are automatically converted to 8 bit bitpedth image.
+ *
+ * TODO
+ *
+ * sBIT ? iTXT, tEXT and tIME as MetaData ?, pHYS (see below)
+ * 16 bpc support for PDF-1.5. JBIG compression for monochrome image.
+ * Predictor for deflate ?
+ */
+
+#define PNG_DEBUG_STR "PNG"
+#define PNG_DEBUG 3
+
+/*
+ * Write, MNG, Progressive not required.
+ */
+#define PNG_NO_WRITE_SUPPORTED
+#define PNG_NO_MNG_FEATURES
+#define PNG_NO_PROGRESSIVE_READ
+#if 0
+/* 16_TO_8 required. */
+#define PNG_NO_READ_TRANSFORMS
+#endif
+
+#include <png.h>
+#include "pngimage.h"
+
+#define PDF_TRANS_TYPE_NONE 0
+#define PDF_TRANS_TYPE_BINARY 1
+#define PDF_TRANS_TYPE_ALPHA 2
+
+int
+check_for_png (FILE *png_file)
+{
+ unsigned char sigbytes[4];
+
+ rewind (png_file);
+ if (fread (sigbytes, 1, sizeof(sigbytes), png_file) !=
+ sizeof(sigbytes) ||
+ (!png_check_sig (sigbytes, sizeof(sigbytes))))
+ return 0;
+ else
+ return 1;
+}
+
+int
+png_scan_file (struct png_info *info, FILE *png_file)
+{
+ png_bytep stream_data_ptr;
+ int trans_type;
+ /* Libpng stuff */
+ png_structp png_ptr;
+ png_infop png_info_ptr;
+ png_byte bpc, color_type;
+ png_uint_32 width, height, rowbytes;
+
+ rewind (png_file);
+ png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+ if (png_ptr == NULL ||
+ (png_info_ptr = png_create_info_struct (png_ptr)) == NULL) {
+ fprintf(stderr, "WARNING: %s: Creating Libpng read/info struct failed.", PNG_DEBUG_STR);
+ if (png_ptr)
+ png_destroy_read_struct(&png_ptr, NULL, NULL);
+ return -1;
+ }
+
+ /* Inititializing file IO. */
+ png_init_io (png_ptr, png_file);
+
+ /* Read PNG info-header and get some info. */
+ png_read_info(png_ptr, png_info_ptr);
+ color_type = png_get_color_type (png_ptr, png_info_ptr);
+ width = png_get_image_width (png_ptr, png_info_ptr);
+ height = png_get_image_height(png_ptr, png_info_ptr);
+ bpc = png_get_bit_depth (png_ptr, png_info_ptr);
+
+ info->xdpi = png_get_x_pixels_per_meter(png_ptr, png_info_ptr) * 0.0254;
+ info->ydpi = png_get_y_pixels_per_meter(png_ptr, png_info_ptr) * 0.0254;
+
+ if (info->xdpi == 0)
+ info->xdpi = 72;
+ if (info->ydpi == 0)
+ info->ydpi = 72;
+
+ /* Values listed below will not be modified in the remaining process. */
+ info->width = width;
+ info->height = height;
+ info->bits_per_component = bpc;
+
+ /* Cleanup */
+ if (png_info_ptr)
+ png_destroy_info_struct(png_ptr, &png_info_ptr);
+ if (png_ptr)
+ png_destroy_read_struct(&png_ptr, NULL, NULL);
+
+ return 0;
+}