-Level Defines the compression level. Valid values are 1 through 9, Z_BEST_SPEED, Z_BEST_COMPRESSION, and Z_DEFAULT_COMPRESSION. The default is -Level =>Z_DEFAULT_COMPRESSION.

So then:

deflateInit( -Bufsize => 300, 
                 -Level => Z_BEST_SPEED  ) ;
[download]

Then IIRC write the buffer to disk.

HTH
--
idnopheq
Apply yourself to new problems without preparation, develop confidence in your ability to to meet situations as they arrise.

~ Shunryu Suzuki