| <Website> | getID3 |  |
|
| Size: | 3026 |
| Storage flags: | strip |
<?php
class getid3_gif extends getid3_handler
{
public function Analyze() {
$info = &$this->getid3->info;
$info['fileformat'] = 'gif';
$info['video']['dataformat'] = 'gif';
$info['video']['lossless'] = true;
$info['video']['pixel_aspect_ratio'] = (float) 1;
$this->fseek($info['avdataoffset']);
$GIFheader = $this->fread(13);
$offset = 0;
$info['gif']['header']['raw']['identifier'] = substr($GIFheader, $offset, 3);
$offset += 3;
$magic = 'GIF';
if ($info['gif']['header']['raw']['identifier'] != $magic) {
$info['error'][] = 'Expecting "'.getid3_lib::PrintHexBytes($magic).'" at offset '.$info['avdataoffset'].', found "'.getid3_lib::PrintHexBytes($info['gif']['header']['raw']['identifier']).'"';
unset($info['fileformat']);
unset($info['gif']);
return false;
}
$info['gif']['header']['raw']['version'] = substr($GIFheader, $offset, 3);
$offset += 3;
$info['gif']['header']['raw']['width'] = getid3_lib::LittleEndian2Int(substr($GIFheader, $offset, 2));
$offset += 2;
$info['gif']['header']['raw']['height'] = getid3_lib::LittleEndian2Int(substr($GIFheader, $offset, 2));
$offset += 2;
$info['gif']['header']['raw']['flags'] = getid3_lib::LittleEndian2Int(substr($GIFheader, $offset, 1));
$offset += 1;
$info['gif']['header']['raw']['bg_color_index'] = getid3_lib::LittleEndian2Int(substr($GIFheader, $offset, 1));
$offset += 1;
$info['gif']['header']['raw']['aspect_ratio'] = getid3_lib::LittleEndian2Int(substr($GIFheader, $offset, 1));
$offset += 1;
$info['video']['resolution_x'] = $info['gif']['header']['raw']['width'];
$info['video']['resolution_y'] = $info['gif']['header']['raw']['height'];
$info['gif']['version'] = $info['gif']['header']['raw']['version'];
$info['gif']['header']['flags']['global_color_table'] = (bool) ($info['gif']['header']['raw']['flags'] & 0x80);
if ($info['gif']['header']['raw']['flags'] & 0x80) {
$info['gif']['header']['bits_per_pixel'] = 3 * ((($info['gif']['header']['raw']['flags'] & 0x70) >> 4) + 1);
} else {
$info['gif']['header']['bits_per_pixel'] = 0;
}
$info['gif']['header']['flags']['global_color_sorted'] = (bool) ($info['gif']['header']['raw']['flags'] & 0x40);
if ($info['gif']['header']['flags']['global_color_table']) {
$info['gif']['header']['global_color_size'] = pow(2, ($info['gif']['header']['raw']['flags'] & 0x07) + 1);
$info['video']['bits_per_sample'] = ($info['gif']['header']['raw']['flags'] & 0x07) + 1;
} else {
$info['gif']['header']['global_color_size'] = 0;
}
if ($info['gif']['header']['raw']['aspect_ratio'] != 0) {
$info['gif']['header']['aspect_ratio'] = ($info['gif']['header']['raw']['aspect_ratio'] + 15) / 64;
}
return true;
}
public function GetLSBits($bits) {
static $bitbuffer = '';
while (strlen($bitbuffer) < $bits) {
$bitbuffer = str_pad(decbin(ord($this->fread(1))), 8, '0', STR_PAD_LEFT).$bitbuffer;
}
$value = bindec(substr($bitbuffer, 0 - $bits));
$bitbuffer = substr($bitbuffer, 0, 0 - $bits);
return $value;
}
}