/modules/anqh/vendor/exif/makers/gps.php

<?php //================================================================================================

//================================================================================================

//================================================================================================

/*

	Exifer

	Extracts EXIF information from digital photos.

	

	Copyright © 2003 Jake Olefsky

	http://www.offsky.com/software/exif/index.php

	jake@olefsky.com

	

	Please see exif.php for the complete information about this software.

	

	------------

	

	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. http://www.gnu.org/copyleft/gpl.html

*/

//================================================================================================

//================================================================================================

//================================================================================================







//=================

// Looks up the name of the tag

//====================================================================

function lookup_GPS_tag($tag) {



	switch($tag) {

		case "0000": $tag = "Version";break;

		case "0001": $tag = "Latitude Reference";break;			//north or south

		case "0002": $tag = "Latitude";break;					//dd mm.mm or dd mm ss

		case "0003": $tag = "Longitude Reference";break;		//east or west

		case "0004": $tag = "Longitude";break;					//dd mm.mm or dd mm ss

		case "0005": $tag = "Altitude Reference";break;			//sea level or below sea level

		case "0006": $tag = "Altitude";break;					//positive rational number

		case "0007": $tag = "Time";break;						//three positive rational numbers

		case "0008": $tag = "Satellite";break;					//text string up to 999 bytes long

		case "0009": $tag = "ReceiveStatus";break;				//in progress or interop

		case "000a": $tag = "MeasurementMode";break;			//2D or 3D

		case "000b": $tag = "MeasurementPrecision";break;		//positive rational number

		case "000c": $tag = "SpeedUnit";break;					//KPH, MPH, knots

		case "000d": $tag = "ReceiverSpeed";break;				//positive rational number	

		case "000e": $tag = "MovementDirectionRef";break;		//true or magnetic north

		case "000f": $tag = "MovementDirection";break;			//positive rational number

		case "0010": $tag = "ImageDirectionRef";break;			//true or magnetic north

		case "0011": $tag = "ImageDirection";break;				//positive rational number

		case "0012": $tag = "GeodeticSurveyData";break;			//text string up to 999 bytes long

		case "0013": $tag = "DestLatitudeRef";break;			//north or south

		case "0014": $tag = "DestinationLatitude";break;		//three positive rational numbers

		case "0015": $tag = "DestLongitudeRef";break;			//east or west

		case "0016": $tag = "DestinationLongitude";break;		//three positive rational numbers

		case "0017": $tag = "DestBearingRef";break;				//true or magnetic north

		case "0018": $tag = "DestinationBearing";break;			//positive rational number

		case "0019": $tag = "DestDistanceRef";break;			//km, miles, knots

		case "001a": $tag = "DestinationDistance";break;		//positive rational number

		case "001b": $tag = "ProcessingMethod";break;			

		case "001c": $tag = "AreaInformation";break;

		case "001d": $tag = "Datestamp";break;					//text string 10 bytes long

		case "001e": $tag = "DifferentialCorrection";break;		//integer in range 0-65535

		

		

		default: $tag = "unknown:".$tag;break;

	}

	

	return $tag;

}



//=================

// Formats Data for the data type

//====================================================================

function formatGPSData($type,$tag,$intel,$data) {



	if($type=="ASCII") {

		if($tag=="0001" || $tag=="0003"){ // Latitude Reference, Longitude Reference

			$data = ($data{1} == $data{2} && $data{1} == $data{3}) ? $data{0} : $data;

		}



	} else if($type=="URATIONAL" || $type=="SRATIONAL") {

		if($tag=="0002" || $tag=="0004" || $tag=='0007') { //Latitude, Longitude, Time
			$datum = array();
			for ($i=0;$i<strlen($data);$i=$i+8) {
				array_push($datum,substr($data, $i, 8));
			}
			$hour = unRational($datum[0],$type,$intel);

			$minutes = unRational($datum[1],$type,$intel);
			$seconds = unRational($datum[2],$type,$intel);
			if($tag=="0007") { //Time

				$data = $hour.":".$minutes.":".$seconds;
			} else {
				$data = $hour+$minutes/60+$seconds/3600;
			}
		} else {

			$data = unRational($data,$type,$intel);
			
			if($tag=="0006"){

				$data .= 'm';

			}

		}

	} else if($type=="USHORT" || $type=="SSHORT" || $type=="ULONG" || $type=="SLONG" || $type=="FLOAT" || $type=="DOUBLE") {

		$data = rational($data,$type,$intel);





	} else if($type=="UNDEFINED") {







	} else if($type=="UBYTE") {

		$data = bin2hex($data);

		if($intel==1) $num = intel2Moto($data);



			

		if($tag=="0000") { // VersionID

			$data =  hexdec(substr($data,0,2)) .

												".". hexdec(substr($data,2,2)) .

												".". hexdec(substr($data,4,2)) .

												".". hexdec(substr($data,6,2));



		} else if($tag=="0005"){ // Altitude Reference

			if($data == "00000000"){ $data = '+'; }

			else if($data == "01000000"){ $data = '-'; }

		}



	} else {

		$data = bin2hex($data);

		if($intel==1) $data = intel2Moto($data);

	}



	return $data;

}





//=================

// GPS Special data section

// Useful websites

// http://drewnoakes.com/code/exif/sampleOutput.html

// http://www.geosnapper.com

//====================================================================

function parseGPS($block,&$result,$offset,$seek, $globalOffset) {	

	

	if($result['Endien']=="Intel") $intel=1;

	else $intel=0;

		

	$v = fseek($seek,$globalOffset+$offset);  //offsets are from TIFF header which is 12 bytes from the start of the file

	if($v==-1) {

		$result['Errors'] = $result['Errors']++;

	}



	$num = bin2hex(fread( $seek, 2 ));

	if($intel==1) $num = intel2Moto($num);

	$num=hexdec($num);

	$result['GPS']['NumTags'] = $num;



	if ($num == 0) {

		return;

	}



	$block = fread( $seek, $num*12 );

	$place = 0;

	

	//loop thru all tags  Each field is 12 bytes

	for($i=0;$i<$num;$i++) {

			//2 byte tag

		$tag = bin2hex(substr($block,$place,2));$place+=2;

		if($intel==1) $tag = intel2Moto($tag);

		$tag_name = lookup_GPS_tag($tag);

		

		//2 byte datatype

		$type = bin2hex(substr($block,$place,2));$place+=2;

		if($intel==1) $type = intel2Moto($type);

		lookup_type($type,$size);

		

		//4 byte number of elements

		$count = bin2hex(substr($block,$place,4));$place+=4;

		if($intel==1) $count = intel2Moto($count);

		$bytesofdata = $size*hexdec($count);

		

		//4 byte value or pointer to value if larger than 4 bytes

		$value = substr($block,$place,4);$place+=4;

		if($bytesofdata<=4) {
			$data = $value;

		} else {

			if (strpos('unknown',$tag_name) !== false || $bytesofdata > 1024) {

				$result['Errors'] = $result['Errors']++;

				$data = '';

				$type = 'ASCII';

			} else {

				$value = bin2hex($value);

				if($intel==1) $value = intel2Moto($value);

				$v = fseek($seek,$globalOffset+hexdec($value));  //offsets are from TIFF header which is 12 bytes from the start of the file

				if($v==0) {

					$data = fread($seek, $bytesofdata);

				} else {

					$result['Errors'] = $result['Errors']++;

					$data = '';

					$type = 'ASCII';

				}

			}

		}

		if($result['VerboseOutput']==1) {

			$result['GPS'][$tag_name] = formatGPSData($type,$tag,$intel,$data);

			$result['GPS'][$tag_name."_Verbose"]['RawData'] = bin2hex($data);

			$result['GPS'][$tag_name."_Verbose"]['Type'] = $type;

			$result['GPS'][$tag_name."_Verbose"]['Bytes'] = $bytesofdata;

		} else {

			$result['GPS'][$tag_name] = formatGPSData($type,$tag,$intel,$data);

		}
	}

}





?>