+Received: from sog-mx-3.v43.ch3.sourceforge.com ([172.29.43.193]

+ helo=mx.sourceforge.net)

+ by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76)

+ (envelope-from <gcbd-bitcoin-development@m.gmane.org>)

+ id 1YQxIR-0000NC-5p for bitcoin-development@lists.sourceforge.net;

+ Thu, 26 Feb 2015 12:12:03 +0000

+Received-SPF: pass (sog-mx-3.v43.ch3.sourceforge.com: domain of m.gmane.org

+ designates 80.91.229.3 as permitted sender)

+ client-ip=80.91.229.3;

+ envelope-from=gcbd-bitcoin-development@m.gmane.org;

+ helo=plane.gmane.org;

+Received: from plane.gmane.org ([80.91.229.3])

+ by sog-mx-3.v43.ch3.sourceforge.com with esmtps (TLSv1:AES256-SHA:256)

+ (Exim 4.76) id 1YQxIP-0005j8-R5

+ for bitcoin-development@lists.sourceforge.net;

+ Thu, 26 Feb 2015 12:12:03 +0000

+Received: from list by plane.gmane.org with local (Exim 4.69)

+ (envelope-from <gcbd-bitcoin-development@m.gmane.org>)

+ id 1YQxII-00078o-Ob for bitcoin-development@lists.sourceforge.net;

+ Thu, 26 Feb 2015 13:11:54 +0100

+Received: from f052018132.adsl.alicedsl.de ([78.52.18.132])

+ by main.gmane.org with esmtp (Gmexim 0.1 (Debian))

+ id 1AlnuQ-0007hv-00 for <bitcoin-development@lists.sourceforge.net>;

+ Thu, 26 Feb 2015 13:11:54 +0100

+Received: from andreas by f052018132.adsl.alicedsl.de with local (Gmexim 0.1

+ (Debian)) id 1AlnuQ-0007hv-00

+ for <bitcoin-development@lists.sourceforge.net>;

+ Thu, 26 Feb 2015 13:11:54 +0100

+X-Injected-Via-Gmane: http://gmane.org/

+To: bitcoin-development@lists.sourceforge.net

+From: Andreas Schildbach <andreas@schildbach.de>

+Date: Thu, 26 Feb 2015 13:11:48 +0100

+Message-ID: <54EF0D84.5070301@schildbach.de>

+References: <771EF431-6644-4BE4-B39C-CA73CFC18DB4@gmail.com> <54EEE81F.1000602@schildbach.de> <E7A57403-A898-461D-9750-A3A0001D82EB@gmail.com> <54EEF12B.2050803@schildbach.de>

+ <DFD6CE20-6B88-4629-BF5E-23250C306B6E@gmail.com>

+Mime-Version: 1.0

+Content-Type: text/plain; charset=windows-1252

+Content-Transfer-Encoding: 8bit

+X-Complaints-To: usenet@ger.gmane.org

+X-Gmane-NNTP-Posting-Host: f052018132.adsl.alicedsl.de

+User-Agent: Mozilla/5.0 (X11; Linux x86_64;

+ rv:31.0) Gecko/20100101 Thunderbird/31.4.0

+In-Reply-To: <DFD6CE20-6B88-4629-BF5E-23250C306B6E@gmail.com>

+X-Spam-Score: -0.4 (/)

+X-Spam-Report: Spam Filtering performed by mx.sourceforge.net.

+ See http://spamassassin.org/tag/ for more details.

+ -1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for

+ sender-domain

+ -0.0 SPF_HELO_PASS SPF: HELO matches SPF record

+ 1.1 DKIM_ADSP_ALL No valid author signature,

+ domain signs all mail

+ -0.0 T_RP_MATCHES_RCVD Envelope sender domain matches handover relay

+ domain

+ -0.0 SPF_PASS SPF: sender matches SPF record

+ 0.0 AWL AWL: Adjusted score from AWL reputation of From: address

+X-Headers-End: 1YQxIP-0005j8-R5

+Subject: Re: [Bitcoin-development] Providing Payment Request within URI

+X-BeenThere: bitcoin-development@lists.sourceforge.net

+X-Mailman-Version: 2.1.9

+Precedence: list

+List-Id: <bitcoin-development.lists.sourceforge.net>

+List-Unsubscribe: <https://lists.sourceforge.net/lists/listinfo/bitcoin-development>,

+ <mailto:bitcoin-development-request@lists.sourceforge.net?subject=unsubscribe>

+List-Archive: <http://sourceforge.net/mailarchive/forum.php?forum_name=bitcoin-development>

+List-Post: <mailto:bitcoin-development@lists.sourceforge.net>

+List-Help: <mailto:bitcoin-development-request@lists.sourceforge.net?subject=help>

+List-Subscribe: <https://lists.sourceforge.net/lists/listinfo/bitcoin-development>,

+ <mailto:bitcoin-development-request@lists.sourceforge.net?subject=subscribe>

+X-List-Received-Date: Thu, 26 Feb 2015 12:12:03 -0000

+

+On 02/26/2015 12:14 PM, Oleg Andreev wrote:

+>

+>> Base43 is the same as any BaseX standard, but using a different alphabet

+>> (43 characters). It's meant to be used for efficiently storing binary

+>> data into QR codes. The alphabet is picked to match the 'Alphanumeric'

+>> input mode of QR codes as closely as possible, but at the same time be

+>> allowed in URIs.

+>

+> Does it mean Base58 or Base64 take more space in QR code than Base43? Do you have an estimate of the gains?

+

+Both Base58 and Base64 force QR codes into binary encoding. Base64 can

+take 6 bits per char, binary of course has 8 bits per char. So you're

+wasting 25% of space if you use Base64, a little bit more with Base58.

+

+Base43 takes log2(43) = 5.43 bits per char, while each char uses up 5.5

+bits in QR codes in 'Alphanumeric' encoding. So that's a waste of 1.3%.

+

+Source for QR code standard: http://en.wikipedia.org/wiki/QR_code

+

+

+

+