/includes/exifer1_5/makers/gps.php
PHP | 238 lines | 143 code | 46 blank | 49 comment | 63 complexity | e59bd871e0792139bc33d971540812f3 MD5 | raw file
Possible License(s): GPL-2.0
- <?php
- // SVN file version:
- // $Id$
- //================================================================================================
- //================================================================================================
- //================================================================================================
- /*
- Exifer
- Extracts EXIF information from digital photos.
-
- Copyright Š 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 $tag;
- }
- //=================
- // Formats a rational number
- //====================================================================
- function GPSRational($data, $intel) {
- if($intel==1) $top = hexdec(substr($data,8,8)); //intel stores them bottom-top
- else $top = hexdec(substr($data,0,8)); //motorola stores them top-bottom
-
- if($intel==1) $bottom = hexdec(substr($data,0,8)); //intel stores them bottom-top
- else $bottom = hexdec(substr($data,8,8)); //motorola stores them top-bottom
-
- if($bottom!=0) $data=$top/$bottom;
- else if($top==0) $data = 0;
- else $data=$top."/".$bottom;
-
- return $data;
- }
- //=================
- // Formats Data for the data type
- //====================================================================
- function formatGPSData($type,$tag,$intel,$data) {
- if($type=="ASCII") {
-
-
- } else if($type=="URATIONAL" || $type=="SRATIONAL") {
- $data = bin2hex($data);
- if($intel==1) $data = intel2Moto($data);
-
- if($intel==1) $top = hexdec(substr($data,8,8)); //intel stores them bottom-top
- else $top = hexdec(substr($data,0,8)); //motorola stores them top-bottom
-
- if($intel==1) $bottom = hexdec(substr($data,0,8)); //intel stores them bottom-top
- else $bottom = hexdec(substr($data,8,8)); //motorola stores them top-bottom
-
- if($type=="SRATIONAL" && $top>2147483647) $top = $top - 4294967296; //this makes the number signed instead of unsigned
-
- if($tag=="0002" || $tag=="0004") { //Latitude
- //fix from Scott Menzer at the forums.
- if ($intel==1) {
- $seconds = GPSRational(substr($data,0,16),$intel);
- $minutes = GPSRational(substr($data,16,16),$intel);
- $hour = GPSRational(substr($data,32,16),$intel);
- } else {
- $hour = GPSRational(substr($data,0,16),$intel);
- $minutes = GPSRational(substr($data,16,16),$intel);
- $seconds = GPSRational(substr($data,32,16),$intel);
- }
-
- $data = $hour+$minutes/60+$seconds/3600;
- } else if($tag=="0007") { //Time
- $seconds = GPSRational(substr($data,0,16),$intel);
- $minutes = GPSRational(substr($data,16,16),$intel);
- $hour = GPSRational(substr($data,32,16),$intel);
-
- $data = $hour.":".$minutes.":".$seconds;
- } else {
- if($bottom!=0) $data=$top/$bottom;
- else if($top==0) $data = 0;
- else $data=$top."/".$bottom;
- }
- } else if($type=="USHORT" || $type=="SSHORT" || $type=="ULONG" || $type=="SLONG" || $type=="FLOAT" || $type=="DOUBLE") {
- $data = bin2hex($data);
- if($intel==1) $data = intel2Moto($data);
- $data=hexdec($data);
-
-
- } else if($type=="UNDEFINED") {
-
-
-
- } else if($type=="UBYTE") {
- $data = bin2hex($data);
- if($intel==1) $num = intel2Moto($data);
-
- if($tag=="0000") { //Latitude
- $data = hexdec(substr($data,0,2)).".". hexdec(substr($data,2,2)).".". hexdec(substr($data,4,2)).".". hexdec(substr($data,6,2));
- }
-
- } 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) $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 {
- $value = bin2hex($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 && $bytesofdata < $GLOBALS['exiferFileSize']) {
- $data = fread($seek, $bytesofdata);
- } else {
- $result['Errors'] = $result['Errors']++;
- }
- }
-
- if($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);
- }
- }
- }
- ?>