This class can hold a timestamp, and it will be used as
in this example where the time is advanced by one week:
$entry = $ifd->getEntry(PelTag::DATE_TIME_ORIGINAL);
$time = $entry->getValue();
print('The image was taken on the ' . date('jS', $time));
$entry->setValue($time + 7 * 24 * 3600);
The example used a standard UNIX timestamp, which is the default
for this class.
But the Exif format defines dates outside the range of a UNIX
timestamp (about 1970 to 2038) and so you can also get access to
the timestamp in two other formats: a simple string or a Julian Day
Count. Please see the Calendar extension in the PHP Manual for more
information about the Julian Day Count.
function testTime()
{
$entry = new PelEntryTime(42, 10);
$this->assertEquals($entry->getComponents(), 20);
$this->assertEquals($entry->getValue(), 10);
$this->assertEquals($entry->getValue(PelEntryTime::UNIX_TIMESTAMP), 10);
$this->assertEquals($entry->getValue(PelEntryTime::EXIF_STRING), '1970:01:01 00:00:10');
$this->assertEquals($entry->getValue(PelEntryTime::JULIAN_DAY_COUNT), 2440588 + 10 / 86400);
$this->assertEquals($entry->getText(), '1970:01:01 00:00:10');
// Malformed Exif timestamp.
$entry->setValue('1970!01-01 00 00 30', PelEntryTime::EXIF_STRING);
$this->assertEquals($entry->getValue(), 30);
$entry->setValue(2415021.75, PelEntryTime::JULIAN_DAY_COUNT);
// This is Jan 1st 1900 at 18:00, outside the range of a UNIX
// timestamp:
$this->assertEquals($entry->getValue(), false);
$this->assertEquals($entry->getValue(PelEntryTime::EXIF_STRING), '1900:01:01 18:00:00');
$this->assertEquals($entry->getValue(PelEntryTime::JULIAN_DAY_COUNT), 2415021.75);
$entry->setValue('0000:00:00 00:00:00', PelEntryTime::EXIF_STRING);
$this->assertEquals($entry->getValue(), false);
$this->assertEquals($entry->getValue(PelEntryTime::EXIF_STRING), '0000:00:00 00:00:00');
$this->assertEquals($entry->getValue(PelEntryTime::JULIAN_DAY_COUNT), 0);
$entry->setValue('9999:12:31 23:59:59', PelEntryTime::EXIF_STRING);
// this test will fail on 32bit machines
$this->assertEquals($entry->getValue(), 253402300799);
$this->assertEquals($entry->getValue(PelEntryTime::EXIF_STRING), '9999:12:31 23:59:59');
$this->assertEquals($entry->getValue(PelEntryTime::JULIAN_DAY_COUNT), 5373484 + 86399 / 86400);
// Check day roll-over for SF bug #1699489.
$entry->setValue('2007:04:23 23:30:00', PelEntryTime::EXIF_STRING);
$t = $entry->getValue(PelEntryTime::UNIX_TIMESTAMP);
$entry->setValue($t + 3600);
$this->assertEquals($entry->getValue(PelEntryTime::EXIF_STRING), '2007:04:24 00:30:00');
}
function testTime()
{
$arg1 = new PatternExpectation('/Missing argument 1 for lsolesen.pel.PelEntryTime::__construct()/');
$arg2 = new PatternExpectation('/Missing argument 2 for lsolesen.pel.PelEntryTime::__construct()/');
$this->expectError($arg1);
$this->expectError($arg2);
$this->expectError('Undefined variable: tag');
$this->expectError('Undefined variable: timestamp');
$entry = new PelEntryTime();
$this->expectError($arg2);
$this->expectError('Undefined variable: timestamp');
$entry = new PelEntryTime(42);
$entry = new PelEntryTime(42, 10);
$this->assertEqual($entry->getComponents(), 20);
$this->assertEqual($entry->getValue(), 10);
$this->assertEqual($entry->getValue(PelEntryTime::UNIX_TIMESTAMP), 10);
$this->assertEqual($entry->getValue(PelEntryTime::EXIF_STRING), '1970:01:01 00:00:10');
$this->assertEqual($entry->getValue(PelEntryTime::JULIAN_DAY_COUNT), 2440588 + 10 / 86400);
$this->assertEqual($entry->getText(), '1970:01:01 00:00:10');
// Malformed Exif timestamp.
$entry->setValue('1970!01-01 00 00 30', PelEntryTime::EXIF_STRING);
$this->assertEqual($entry->getValue(), 30);
$entry->setValue(2415021.75, PelEntryTime::JULIAN_DAY_COUNT);
// This is Jan 1st 1900 at 18:00, outside the range of a UNIX
// timestamp:
$this->assertEqual($entry->getValue(), false);
$this->assertEqual($entry->getValue(PelEntryTime::EXIF_STRING), '1900:01:01 18:00:00');
$this->assertEqual($entry->getValue(PelEntryTime::JULIAN_DAY_COUNT), 2415021.75);
$entry->setValue('0000:00:00 00:00:00', PelEntryTime::EXIF_STRING);
$this->assertEqual($entry->getValue(), false);
$this->assertEqual($entry->getValue(PelEntryTime::EXIF_STRING), '0000:00:00 00:00:00');
$this->assertEqual($entry->getValue(PelEntryTime::JULIAN_DAY_COUNT), 0);
$entry->setValue('9999:12:31 23:59:59', PelEntryTime::EXIF_STRING);
// this test will fail on 32bit machines
$this->assertEqual($entry->getValue(), 253402300799);
$this->assertEqual($entry->getValue(PelEntryTime::EXIF_STRING), '9999:12:31 23:59:59');
$this->assertEqual($entry->getValue(PelEntryTime::JULIAN_DAY_COUNT), 5373484 + 86399 / 86400);
// Check day roll-over for SF bug #1699489.
$entry->setValue('2007:04:23 23:30:00', PelEntryTime::EXIF_STRING);
$t = $entry->getValue(PelEntryTime::UNIX_TIMESTAMP);
$entry->setValue($t + 3600);
$this->assertEqual($entry->getValue(PelEntryTime::EXIF_STRING), '2007:04:24 00:30:00');
}