phpthumb.bmp.php

是一款免费的轻量级论坛软件

											foreach ($paletteindexes as $paletteindex) {
												$col = $pixelcounter % $thisfile_bmp_header_raw['width'];
												$row = $thisfile_bmp_header_raw['height'] - 1 - (($pixelcounter - $col) / $thisfile_bmp_header_raw['width']);
												$thisfile_bmp['data'][$row][$col] = $thisfile_bmp['palette'][$paletteindex];
												$pixelcounter++;
											}
											break;
									}

								} else {

									// encoded mode - the first byte of the pair contains the number of pixels to be
									// drawn using the color indexes in the second byte. The second byte contains two
									// color indexes, one in its high-order 4 bits and one in its low-order 4 bits.
									// The first of the pixels is drawn using the color specified by the high-order
									// 4 bits, the second is drawn using the color in the low-order 4 bits, the third
									// is drawn using the color in the high-order 4 bits, and so on, until all the
									// pixels specified by the first byte have been drawn.
									$paletteindexes[0] = ($secondbyte & 0xF0) >> 4;
									$paletteindexes[1] = ($secondbyte & 0x0F);
									for ($i = 0; $i < $firstbyte; $i++) {
										$col = $pixelcounter % $thisfile_bmp_header_raw['width'];
										$row = $thisfile_bmp_header_raw['height'] - 1 - (($pixelcounter - $col) / $thisfile_bmp_header_raw['width']);
										$thisfile_bmp['data'][$row][$col] = $thisfile_bmp['palette'][$paletteindexes[($i % 2)]];
										$pixelcounter++;
									}

								}
							}
							break;

						default:
							$ThisFileInfo['error'][] = 'Unknown bits-per-pixel value ('.$thisfile_bmp_header_raw['bits_per_pixel'].') - cannot read pixel data';
							break;
					}
					break;


				case 3: // BI_BITFIELDS
					switch ($thisfile_bmp_header_raw['bits_per_pixel']) {
						case 16:
						case 32:
							$redshift   = 0;
							$greenshift = 0;
							$blueshift  = 0;
							if (!$thisfile_bmp_header_raw['red_mask'] || !$thisfile_bmp_header_raw['green_mask'] || !$thisfile_bmp_header_raw['blue_mask']) {
								$ThisFileInfo['error'][] = 'missing $thisfile_bmp_header_raw[(red|green|blue)_mask]';
								return false;
							}
							while ((($thisfile_bmp_header_raw['red_mask'] >> $redshift) & 0x01) == 0) {
								$redshift++;
							}
							while ((($thisfile_bmp_header_raw['green_mask'] >> $greenshift) & 0x01) == 0) {
								$greenshift++;
							}
							while ((($thisfile_bmp_header_raw['blue_mask'] >> $blueshift) & 0x01) == 0) {
								$blueshift++;
							}
							for ($row = ($thisfile_bmp_header_raw['height'] - 1); $row >= 0; $row--) {
								for ($col = 0; $col < $thisfile_bmp_header_raw['width']; $col++) {
									$pixelvalue = $this->LittleEndian2Int(substr($BMPpixelData, $pixeldataoffset, $thisfile_bmp_header_raw['bits_per_pixel'] / 8));
									$pixeldataoffset += $thisfile_bmp_header_raw['bits_per_pixel'] / 8;

									$red   = intval(round(((($pixelvalue & $thisfile_bmp_header_raw['red_mask'])   >> $redshift)   / ($thisfile_bmp_header_raw['red_mask']   >> $redshift))   * 255));
									$green = intval(round(((($pixelvalue & $thisfile_bmp_header_raw['green_mask']) >> $greenshift) / ($thisfile_bmp_header_raw['green_mask'] >> $greenshift)) * 255));
									$blue  = intval(round(((($pixelvalue & $thisfile_bmp_header_raw['blue_mask'])  >> $blueshift)  / ($thisfile_bmp_header_raw['blue_mask']  >> $blueshift))  * 255));
									$thisfile_bmp['data'][$row][$col] = (($red << 16) | ($green << 8) | ($blue));
								}
								while (($pixeldataoffset % 4) != 0) {
									// lines are padded to nearest DWORD
									$pixeldataoffset++;
								}
							}
							break;

						default:
							$ThisFileInfo['error'][] = 'Unknown bits-per-pixel value ('.$thisfile_bmp_header_raw['bits_per_pixel'].') - cannot read pixel data';
							break;
					}
					break;


				default: // unhandled compression type
					$ThisFileInfo['error'][] = 'Unknown/unhandled compression type value ('.$thisfile_bmp_header_raw['compression'].') - cannot decompress pixel data';
					break;
			}
		}

		return true;
	}

	function IntColor2RGB($color) {
		$red   = ($color & 0x00FF0000) >> 16;
		$green = ($color & 0x0000FF00) >> 8;
		$blue  = ($color & 0x000000FF);
		return array($red, $green, $blue);
	}

	function PlotPixelsGD(&$BMPdata, $truecolor=true) {
		$imagewidth  = $BMPdata['header']['raw']['width'];
		$imageheight = $BMPdata['header']['raw']['height'];

		if ($truecolor) {

			$gd = @ImageCreateTrueColor($imagewidth, $imageheight);

		} else {

			$gd = @ImageCreate($imagewidth, $imageheight);
			if (!empty($BMPdata['palette'])) {
				// create GD palette from BMP palette
				foreach ($BMPdata['palette'] as $color) {
					list($r, $g, $b) = $this->IntColor2RGB($color);
					ImageColorAllocate($gd, $r, $g, $b);
				}
			} else {
				// create 216-color websafe palette
				for ($r = 0x00; $r <= 0xFF; $r += 0x33) {
					for ($g = 0x00; $g <= 0xFF; $g += 0x33) {
						for ($b = 0x00; $b <= 0xFF; $b += 0x33) {
							ImageColorAllocate($gd, $r, $g, $b);
						}
					}
				}
			}

		}
		if (!is_resource($gd)) {
			return false;
		}

		foreach ($BMPdata['data'] as $row => $colarray) {
			@set_time_limit(30);
			foreach ($colarray as $col => $color) {
				list($red, $green, $blue) = $this->IntColor2RGB($color);
				if ($truecolor) {
					$pixelcolor = ImageColorAllocate($gd, $red, $green, $blue);
				} else {
					$pixelcolor = ImageColorClosest($gd, $red, $green, $blue);
				}
				ImageSetPixel($gd, $col, $row, $pixelcolor);
			}
		}
		return $gd;
	}

	function PlotBMP(&$BMPinfo) {
		$starttime = time();
		if (!isset($BMPinfo['bmp']['data']) || !is_array($BMPinfo['bmp']['data'])) {
			echo 'ERROR: no pixel data<br />';
			return false;
		}
		set_time_limit(intval(round($BMPinfo['resolution_x'] * $BMPinfo['resolution_y'] / 10000)));
		$im = $this->PlotPixelsGD($BMPinfo['bmp']);
		if (headers_sent()) {
			echo 'plotted '.($BMPinfo['resolution_x'] * $BMPinfo['resolution_y']).' pixels in '.(time() - $starttime).' seconds<br />';
			ImageDestroy($im);
			exit;
		} else {
			header('Content-Type: image/png');
			ImagePNG($im);
			ImageDestroy($im);
			return true;
		}
		return false;
	}

	function BMPcompressionWindowsLookup($compressionid) {
		static $BMPcompressionWindowsLookup = array(
			0 => 'BI_RGB',
			1 => 'BI_RLE8',
			2 => 'BI_RLE4',
			3 => 'BI_BITFIELDS',
			4 => 'BI_JPEG',
			5 => 'BI_PNG'
		);
		return (isset($BMPcompressionWindowsLookup[$compressionid]) ? $BMPcompressionWindowsLookup[$compressionid] : 'invalid');
	}

	function BMPcompressionOS2Lookup($compressionid) {
		static $BMPcompressionOS2Lookup = array(
			0 => 'BI_RGB',
			1 => 'BI_RLE8',
			2 => 'BI_RLE4',
			3 => 'Huffman 1D',
			4 => 'BI_RLE24',
		);
		return (isset($BMPcompressionOS2Lookup[$compressionid]) ? $BMPcompressionOS2Lookup[$compressionid] : 'invalid');
	}


	// from getid3.lib.php

	function trunc($floatnumber) {
		// truncates a floating-point number at the decimal point
		// returns int (if possible, otherwise float)
		if ($floatnumber >= 1) {
			$truncatednumber = floor($floatnumber);
		} elseif ($floatnumber <= -1) {
			$truncatednumber = ceil($floatnumber);
		} else {
			$truncatednumber = 0;
		}
		if ($truncatednumber <= 1073741824) { // 2^30
			$truncatednumber = (int) $truncatednumber;
		}
		return $truncatednumber;
	}

	function LittleEndian2Int($byteword) {
		$intvalue = 0;
		$byteword = strrev($byteword);
		$bytewordlen = strlen($byteword);
		for ($i = 0; $i < $bytewordlen; $i++) {
			$intvalue += ord($byteword{$i}) * pow(256, ($bytewordlen - 1 - $i));
		}
		return $intvalue;
	}

	function BigEndian2Int($byteword) {
		return $this->LittleEndian2Int(strrev($byteword));
	}

	function BigEndian2Bin($byteword) {
		$binvalue = '';
		$bytewordlen = strlen($byteword);
		for ($i = 0; $i < $bytewordlen; $i++) {
			$binvalue .= str_pad(decbin(ord($byteword{$i})), 8, '0', STR_PAD_LEFT);
		}
		return $binvalue;
	}

	function FixedPoint2_30($rawdata) {
		$binarystring = $this->BigEndian2Bin($rawdata);
		return $this->Bin2Dec(substr($binarystring, 0, 2)) + (float) ($this->Bin2Dec(substr($binarystring, 2, 30)) / 1073741824);
	}

	function Bin2Dec($binstring, $signed=false) {
		$signmult = 1;
		if ($signed) {
			if ($binstring{0} == '1') {
				$signmult = -1;
			}
			$binstring = substr($binstring, 1);
		}
		$decvalue = 0;
		for ($i = 0; $i < strlen($binstring); $i++) {
			$decvalue += ((int) substr($binstring, strlen($binstring) - $i - 1, 1)) * pow(2, $i);
		}
		return $this->CastAsInt($decvalue * $signmult);
	}

	function CastAsInt($floatnum) {
		// convert to float if not already
		$floatnum = (float) $floatnum;

		// convert a float to type int, only if possible
		if ($this->trunc($floatnum) == $floatnum) {
			// it's not floating point
			if ($floatnum <= 1073741824) { // 2^30
				// it's within int range
				$floatnum = (int) $floatnum;
			}
		}
		return $floatnum;
	}

}

?>