--- /dev/null
+<?php
+
+// Simple .ICO parsing. The ICO format is insanely complex and this may
+// fail to correctly handle some technically valid files, but it works
+// on the majority I've found.
+//
+// jimIcon was written in 2013 by Jim Paris <jim@jtan.com> and is
+// released under the terms of the CC0:
+//
+// To the extent possible under law, the author(s) have dedicated all
+// copyright and related and neighboring rights to this software to
+// the public domain worldwide. This software is distributed without
+// any arranty.
+//
+// You may have received a copy of the CC0 Public Domain Dedication
+// along with this software. If not, see
+// http://creativecommons.org/publicdomain/zero/1.0/
+
+class jimIcon {
+ // Get an image color from a string
+ function get_color($str, $img) {
+ $b = ord($str[0]);
+ $g = ord($str[1]);
+ $r = ord($str[2]);
+ if (strlen($str) > 3) {
+ $a = 127 - (ord($str[3]) / 2);
+ if ($a != 0 && $a != 127)
+ $this->had_alpha = 1;
+ } else {
+ $a = 0;
+ }
+ if ($a != 127)
+ $this->all_transaprent = 0;
+ return imagecolorallocatealpha($img, $r, $g, $b, $a);
+ }
+
+ // Given a string with the contents of an .ICO,
+ // return a GD image of the icon, or false on error.
+ function fromiconstring($ico) {
+ $this->error = "(unknown error)";
+ $this->had_alpha = 0;
+
+ // Read header
+ if (strlen($ico) < 6) {
+ $this->error = "too short";
+ return false;
+ }
+ $h = unpack("vzero/vtype/vnum", $ico);
+
+ // Must be ICO format with at least one image
+ if ($h["zero"] != 0 || $h["type"] != 1 || $h["num"] == 0) {
+ // See if we can just parse it with GD directly
+ // if it's not ICO format; maybe it was a mislabeled
+ // PNG or something.
+ $i = @imagecreatefromstring($ico);
+ if ($i) {
+ imagesavealpha($i, true);
+ return $i;
+ }
+ $this->error = "not ICO or other image";
+ return false;
+ }
+
+ // Read directory entries to find the biggest image
+ $most_pixels = 0;
+ for ($i = 0; $i < $h["num"]; $i++) {
+ $entry = substr($ico, 6 + 16 * $i, 16);
+ if (!$entry || strlen($entry) < 16)
+ continue;
+ $e = unpack("Cwidth/" .
+ "Cheight/" .
+ "Ccolors/" .
+ "Czero/" .
+ "vplanes/" .
+ "vbpp/" .
+ "Vsize/" .
+ "Voffset/",
+ $entry);
+ if ($e["width"] == 0)
+ $e["width"] = 256;
+ if ($e["height"] == 0)
+ $e["height"] = 256;
+ if ($e["zero"] != 0) {
+ $this->error = "nonzero reserved field";
+ return false;
+ }
+ $pixels = $e["width"] * $e["height"];
+ if ($pixels > $most_pixels) {
+ $most_pixels = $pixels;
+ $most = $e;
+ }
+ }
+ if ($most_pixels == 0) {
+ $this->error = "no pixels";
+ return false;
+ }
+ $e = $most;
+
+ // Extract image data
+ $data = substr($ico, $e["offset"], $e["size"]);
+ if (!$data || strlen($data) != $e["size"]) {
+ $this->error = "bad image data";
+ return false;
+ }
+
+ // See if we can parse it (might be PNG format here)
+ $i = @imagecreatefromstring($data);
+ if ($i) {
+ imagesavealpha($img, true);
+ return $i;
+ }
+
+ // Must be a BMP. Parse it ourselves.
+ $img = imagecreatetruecolor($e["width"], $e["height"]);
+ imagesavealpha($img, true);
+ $bg = imagecolorallocatealpha($img, 255, 0, 0, 127);
+ imagefill($img, 0, 0, $bg);
+
+ // Skip over the BITMAPCOREHEADER or BITMAPINFOHEADER;
+ // we'll just assume the palette and pixel data follow
+ // in the most obvious format as described by the icon
+ // directory entry.
+ $bitmapinfo = unpack("Vsize", $data);
+ if ($bitmapinfo["size"] == 40) {
+ $info = unpack("Vsize/" .
+ "Vwidth/" .
+ "Vheight/" .
+ "vplanes/" .
+ "vbpp/" .
+ "Vcompress/" .
+ "Vsize/" .
+ "Vxres/" .
+ "Vyres/" .
+ "Vpalcolors/" .
+ "Vimpcolors/", $data);
+ if ($e["bpp"] == 0) {
+ $e["bpp"] = $info["bpp"];
+ }
+ }
+ $data = substr($data, $bitmapinfo["size"]);
+
+ $height = $e["height"];
+ $width = $e["width"];
+ $bpp = $e["bpp"];
+
+ // For indexed images, we only support 1, 4, or 8 BPP
+ switch ($bpp) {
+ case 1:
+ case 4:
+ case 8:
+ $indexed = 1;
+ break;
+ case 24:
+ case 32:
+ $indexed = 0;
+ break;
+ default:
+ $this->error = "bad BPP $bpp";
+ return false;
+ }
+
+ $offset = 0;
+ if ($indexed) {
+ $palette = array();
+ $this->all_transparent = 1;
+ for ($i = 0; $i < (1 << $bpp); $i++) {
+ $entry = substr($data, $i * 4, 4);
+ $palette[$i] = $this->get_color($entry, $img);
+ }
+ $offset = $i * 4;
+
+ // Hack for some icons: if everything was transparent,
+ // discard alpha channel.
+ if ($this->all_transparent) {
+ for ($i = 0; $i < (1 << $bpp); $i++) {
+ $palette[$i] &= 0xffffff;
+ }
+ }
+ }
+
+ // Assume image data follows in bottom-up order.
+ // First the "XOR" image
+ if ((strlen($data) - $offset) < ($bpp * $height * $width / 8)) {
+ $this->error = "short data";
+ return false;
+ }
+ $XOR = array();
+ for ($y = $height - 1; $y >= 0; $y--) {
+ $x = 0;
+ while ($x < $width) {
+ if (!$indexed) {
+ $bytes = $bpp / 8;
+ $entry = substr($data, $offset, $bytes);
+ $pixel = $this->get_color($entry, $img);
+ $XOR[$y][$x] = $pixel;
+ $x++;
+ $offset += $bytes;
+ } elseif ($bpp == 1) {
+ $p = ord($data[$offset]);
+ for ($b = 0x80; $b > 0; $b >>= 1) {
+ if ($p & $b) {
+ $pixel = $palette[1];
+ } else {
+ $pixel = $palette[0];
+ }
+ $XOR[$y][$x] = $pixel;
+ $x++;
+ }
+ $offset++;
+ } elseif ($bpp == 4) {
+ $p = ord($data[$offset]);
+ $pixel1 = $palette[$p >> 4];
+ $pixel2 = $palette[$p & 0x0f];
+ $XOR[$y][$x] = $pixel1;
+ $XOR[$y][$x+1] = $pixel2;
+ $x += 2;
+ $offset++;
+ } elseif ($bpp == 8) {
+ $pixel = $palette[ord($data[$offset])];
+ $XOR[$y][$x] = $pixel;
+ $x += 1;
+ $offset++;
+ } else {
+ $this->error = "bad BPP";
+ return false;
+ }
+ }
+ // End of row padding
+ while ($offset & 3)
+ $offset++;
+ }
+
+ // Now the "AND" image, which is 1 bit per pixel. Ignore
+ // if some of our image data already had alpha values,
+ // or if there isn't enough data left.
+ if ($this->had_alpha ||
+ ((strlen($data) - $offset) < ($height * $width / 8))) {
+ // Just return what we've got
+ for ($y = 0; $y < $height; $y++) {
+ for ($x = 0; $x < $width; $x++) {
+ imagesetpixel($img, $x, $y,
+ $XOR[$y][$x]);
+ }
+ }
+ return $img;
+ }
+
+ // Mask what we have with the "AND" image
+ for ($y = $height - 1; $y >= 0; $y--) {
+ $x = 0;
+ while ($x < $width) {
+ for ($b = 0x80;
+ $b > 0 && $x < $width; $b >>= 1) {
+ if (!(ord($data[$offset]) & $b)) {
+ imagesetpixel($img, $x, $y,
+ $XOR[$y][$x]);
+ }
+ $x++;
+ }
+ $offset++;
+ }
+
+ // End of row padding
+ while ($offset & 3)
+ $offset++;
+ }
+ return $img;
+ }
+}
+?>
\ No newline at end of file
projects / tt-rss.git / commitdiff