Question about section 5.4 ... 0 in bit 5 means uppercase?

• From: Costello, Roger L. <costello@mitre.org>
• Date: Fri, 1 Jul 2016 17:44:54 +0000
• To: "png-group@w3.org" <png-group@w3.org>
• Message-ID: <BL2PR09MB10112E1CE0130EE3BA500655C8250@BL2PR09MB1011.namprd09.prod.outlook.com>

Hi Folks,

In section 5.4 Chunk Naming Conventions it says:

	Four bits of the chunk type, the property bits, namely
	bit 5 (value 32) of each byte, are used to convey chunk
	properties. This choice means that a human can read
	off the assigned properties according to whether the
 	letter corresponding to each byte of the chunk type is
 	uppercase (bit 5 is 0) or lowercase (bit 5 is 1).

I think the second sentence is saying (or implying) that every uppercase ASCII letter has 0 in bit 5. But that is not true; for example, E is hex 45 (0100 0101), which means it has 1 in bit 5. 

Either I am misunderstanding the second sentence (most likely) or it is a false statement.

Please advise.

/Roger

Received on Friday, 1 July 2016 17:45:30 UTC