Re: [backstage] RE: BBC Flash video and deinterlacing - is this really the best we can get?
From: Brian Butterworth briant...@freeview.tv Subject: Re: [backstage] RE: BBC Flash video and deinterlacing - is this really the best we can get? To: backstage@lists.bbc.co.uk Date: Sunday, 7 March, 2010, 19:15 It occurred to me the other day that one solution to the problem might be to delinterlace the scrolling credits used at the end of programmes on the originals. It might even make them easier to read. But then they'll scroll in a jerky fashion. - Sent via the backstage.bbc.co.uk discussion group. To unsubscribe, please visit http://backstage.bbc.co.uk/archives/2005/01/mailing_list.html. Unofficial list archive: http://www.mail-archive.com/backstage@lists.bbc.co.uk/
Re: [backstage] RE: BBC Flash video and deinterlacing - is this really the best we can get?
On 8 Mar 2010, at 09:04, Kieran Kunhya wrote: From: Brian Butterworth briant...@freeview.tv Subject: Re: [backstage] RE: BBC Flash video and deinterlacing - is this really the best we can get? To: backstage@lists.bbc.co.uk Date: Sunday, 7 March, 2010, 19:15 It occurred to me the other day that one solution to the problem might be to delinterlace the scrolling credits used at the end of programmes on the originals. It might even make them easier to read. But then they'll scroll in a jerky fashion. Clearly you need a motion-compensated deinterlacer. ;-) S - Sent via the backstage.bbc.co.uk discussion group. To unsubscribe, please visit http://backstage.bbc.co.uk/archives/2005/01/mailing_list.html. Unofficial list archive: http://www.mail-archive.com/backstage@lists.bbc.co.uk/
Re: [backstage] RE: BBC Flash video and deinterlacing - is this really the best we can get?
Clearly you need a motion-compensated deinterlacer. ;-) It's still not going to be as good in 25p as it will in 50i in my opinion unless the scroll speed is reduced. Though judging by recent attempts to destroy end credits on virtually every channel I doubt slower speeds will be tolerated... Presumably soon there won't be any end credits but instead viewers will be directed to /programmes . - Sent via the backstage.bbc.co.uk discussion group. To unsubscribe, please visit http://backstage.bbc.co.uk/archives/2005/01/mailing_list.html. Unofficial list archive: http://www.mail-archive.com/backstage@lists.bbc.co.uk/
Re: [backstage] RE: BBC Flash video and deinterlacing - is this really the best we can get?
On 8 Mar 2010, at 11:31, Kieran Kunhya wrote: Clearly you need a motion-compensated deinterlacer. ;-) It's still not going to be as good in 25p as it will in 50i in my opinion unless the scroll speed is reduced. Though judging by recent attempts to destroy end credits on virtually every channel I doubt slower speeds will be tolerated... Presumably soon there won't be any end credits but instead viewers will be directed to /programmes Who said we were deinterlacing to 25p? :-) S - Sent via the backstage.bbc.co.uk discussion group. To unsubscribe, please visit http://backstage.bbc.co.uk/archives/2005/01/mailing_list.html. Unofficial list archive: http://www.mail-archive.com/backstage@lists.bbc.co.uk/
RE: [backstage] RE: BBC Flash video and deinterlacing - is this really the best we can get?
Who said we were deinterlacing to 25p? :-) Looks like 12p for sports programming ;) - Sent via the backstage.bbc.co.uk discussion group. To unsubscribe, please visit http://backstage.bbc.co.uk/archives/2005/01/mailing_list.html. Unofficial list archive: http://www.mail-archive.com/backstage@lists.bbc.co.uk/
Re: [backstage] RE: BBC Flash video and deinterlacing - is this really the best we can get?
Or, of course, you could have pages of text that crossfade - have no scroll at all. They would be much better in that format anyway, because if you ever want to look at the credits, you are going to be using iPlayer or a PVR anyway and the freeze frame would be highly legible. On 8 March 2010 14:29, Christopher Woods chris...@infinitus.co.uk wrote: Who said we were deinterlacing to 25p? :-) Looks like 12p for sports programming ;) - Sent via the backstage.bbc.co.uk discussion group. To unsubscribe, please visit http://backstage.bbc.co.uk/archives/2005/01/mailing_list.html. Unofficial list archive: http://www.mail-archive.com/backstage@lists.bbc.co.uk/ -- Brian Butterworth follow me on twitter: http://twitter.com/briantist web: http://www.ukfree.tv - independent digital television and switchover advice, since 2002
[backstage] User Agent/Referrer Verification
Learned Backstage types, I have invented an algorithm for checking that when a client C accesses a resource M on server S, it can only do so if it also has access to a referring resource R and defines its HTTP User-Agent to be one of a pre-defined list of permitted agents. When C makes the request to S for M, it must include a key, K, which is the result of an sha256-hmac on the contents of R (which both the server and client must have access to, although either could conceivably cache the value of K) using the User-Agent string as the HMAC key. Thus, in order to request M, the client must supply a User-Agent, Referrer and key, K, which all match what the server expects. This goes beyond “dumb” referrer and user-agent checking in that the client must have (or have had recently) access to R in order to correctly generate the key. A sample implementation is here: http://gist.github.com/325815 I’ve written it up here: http://nevali.net/post/435363058/user-agent-referrer-verification Thoughts welcome. M. -- mo mcroberts http://nevali.net iChat: mo.mcrobe...@me.com Jabber/GTalk: m...@ilaven.net Twitter: @nevali Run Leopard or Snow Leopard? Set Quick Look free with DropLook - http://labs.jazzio.com/DropLook/ - Sent via the backstage.bbc.co.uk discussion group. To unsubscribe, please visit http://backstage.bbc.co.uk/archives/2005/01/mailing_list.html. Unofficial list archive: http://www.mail-archive.com/backstage@lists.bbc.co.uk/
[backstage] Re: User Agent/Referrer Verification
On 8-Mar-2010, at 22:55, Mo McRoberts wrote: Learned Backstage types, [snip] I’ve written it up here: http://nevali.net/post/435363058/user-agent-referrer-verification It’s been pointed out to me that the write-up would be better in the e-mail, so here it is: This is a snippet of code which verifies access to a given resource based upon a combination of access to a referring resource and a user-agent string. The client generates an sha256-hmac based on the contents of the referring resource (which the client must have access to) and its user-agent string. This HMAC is sent along with the request for a resource. Thus, given a list of referring resources and valid user agents, the server can generate a list of valid keys by performing the same sha256-hmac process on each combination. If a client sends a request which does not appear in this list of keys, the request is denied. I would be interested on an expert opinion as to whether this is considered an “effective” technological copyright-protection mechanism according to the Copyright, Designs and Patents Act 1988 (as amended by The Copyright and Related Rights Regulation 2003), and whether implementing a third-party client which implements this protocol (for the purposes of interoperability) constitutes “any device, product or component which is primarily designed, produced, or adapted for the purpose of enabling or facilitating the circumvention of effective technological measures” as specified by section 296ZB of the Act. Cheers! M. -- mo mcroberts http://nevali.net iChat: mo.mcrobe...@me.com Jabber/GTalk: m...@ilaven.net Twitter: @nevali Run Leopard or Snow Leopard? Set Quick Look free with DropLook - http://labs.jazzio.com/DropLook/ - Sent via the backstage.bbc.co.uk discussion group. To unsubscribe, please visit http://backstage.bbc.co.uk/archives/2005/01/mailing_list.html. Unofficial list archive: http://www.mail-archive.com/backstage@lists.bbc.co.uk/
