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Base class to draw images
Copyright (C) Jean-Sebastien Goupil http://www.barcodephp.com
$im :
$filename :
$dpi :
$crc_table :
$crc_table_computed :
__construct(resource $im)
Constructor.
setFilename(string $filename)
Sets the filename.
draw()
Draws the PNG on the screen or in a file.
setDPI(integer $dpi)
Sets the DPI.
setInternalProperties( $bin)
detectChunks( $bin)
internalSetDPI( $bin, $chunks)
internalSetC( $bin, $chunks)
make_crc_table()
SHR( $x, $n)
update_crc( $crc, $buf, $len)
crc( $data, $len)