[Bitcoin-development] Combining bloom filters?

[Bitcoin-development] Combining bloom filters?

[Jeff Garzik]

Consider wallet A builds bloom filter A' and wallet B builds bloom
filter B'.  Can A' and B' be or'd together to form a single bloom
filter C' ?

-- 
Jeff Garzik
Senior Software Engineer and open source evangelist
BitPay, Inc.      https://bitpay.com/

Re: [Bitcoin-development] Combining bloom filters?

[bitcoin-list]

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Under some conditions, yes. The filters must have the same parameters (tweak, size, hash count). Bitcoinj implements this in its BloomFilter class.

Matt

Jeff Garzik <jgarzik@bitpay.com> wrote:
>Consider wallet A builds bloom filter A' and wallet B builds bloom
>filter B'.  Can A' and B' be or'd together to form a single bloom
>filter C' ?
>
>-- 
>Jeff Garzik
>Senior Software Engineer and open source evangelist
>BitPay, Inc.      https://bitpay.com/
>
>------------------------------------------------------------------------------
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Re: [Bitcoin-development] Combining bloom filters?

[Pieter Wuille]

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If both constructed bloom filters use the same seed and the same number of
hash functions, yes. Assuming the input filters were optimal for a given FP
rate, the resulting filter will be worse.

-- 
Pieter
 On 17 Aug 2013 16:01, "Jeff Garzik" <jgarzik@bitpay.com> wrote:

> Consider wallet A builds bloom filter A' and wallet B builds bloom
> filter B'.  Can A' and B' be or'd together to form a single bloom
> filter C' ?
>
> --
> Jeff Garzik
> Senior Software Engineer and open source evangelist
> BitPay, Inc.      https://bitpay.com/
>
>
> ------------------------------------------------------------------------------
> Get 100% visibility into Java/.NET code with AppDynamics Lite!
> It's a free troubleshooting tool designed for production.
> Get down to code-level detail for bottlenecks, with <2% overhead.
> Download for free and get started troubleshooting in minutes.
> http://pubads.g.doubleclick.net/gampad/clk?id=48897031&iu=/4140/ostg.clktrk
> _______________________________________________
> Bitcoin-development mailing list
> Bitcoin-development@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/bitcoin-development
>

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