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Crossing Four Way Stops Fast and Searching Closed Caption MCE Videos: More Stolen Thoughts

2008 Jan 22, 9:56

More ideas stolen from me in the same vein as my stolen OpenID thoughts.

Fast Pedestrian Crossing on Four Way Stops. In college I didn't have a car and every weekend I had weekly poker with friends who lived nearby so I would end up waiting to cross from one corner of a traffic lit four way stop to the opposite corner. Waiting there in the cold gave me plenty of time to consider the fastest method of getting to the opposite corner of a four-way stop. My plan was to hit the pedestrian crossing button for both directions and travel on the first one available. This only seems like a bad choice if the pedestrian crossing signal travels clockwise or counter clockwise around the four way stop. In those two cases its better to take the later of the two pedestrian signal crossings, but I have yet to see those two patterns on a real life traffic stop. I decided recently to see if my plan was actually sound and looked up info on traffic signals. But the info didn't say much other than "its complicated" and "it depends" (I'm paraphrasing). Then I found some guy's analysis of this problem. So I'm done with this and I'll continue pressing both buttons and crossing on the first pedestrian signal. Incidentally on one such night when I was waiting to cross this intersection I heard a loud multi-click sound and realized that the woman in the SUV waiting to cross the intersection next to me had just locked her doors. I guess my thinking-about-crossing-the-street face is intimidating.

Windows Searching Windows Media Center Recorded TV's Closed Captions. An Ars-Technica article on a fancy DVR described one of the DVRs features: full text search over the subtitles of the recorded TV shows. I thought implementing this for Windows Media Center recorded TV shows and Windows Search would be an interesting project to learn about video files, and extending Windows Search. As it turns out though some guy, Stephen Toub implemented Windows Search over MCE closed captions already. Stephen Toub's article is very long and describes some other very interesting related projects including 'summarizing video files' which you may want to read.

stolen-thoughts windows search mce windows traffic closed captions four-way-stop windows-media-center

HIMAGELIST Stream Size

2008 Jan 12, 2:26If you're like me you need to serialize an object that contains an HIMAGELIST via IMarshal for COM's marshalling. I could use ImageList_Write to actually write the HIMAGELIST to a stream for IMarshal::MarshalInterface, but I needed to know the size of the data that I was going to write for IMarshal::GetMarshalSizeMax. I thought I'd use HIMAGELIST_QueryInterface to get an IPersistStream pointer which works, but alas its implementation of IPersistStream::GetMaxSize just returns E_NOTIMPL. Ultimately I called ImageList_Write on a special stream that ignores the data passed to it and just records how much data is written to it. In this fashion I could get the size the HIMAGELIST would require when written to a stream.technical himagelist boring serialize imarshal com

IPv6 Roundup: Address Syntax on Windows

2008 Jan 9, 11:34

IPv6 address syntax consists of 8 groupings of colon delimited 16-bit hex values making up the 128-bit address. An optional double colon can replace any consecutive sequence of 0 valued hex values. For example the following is a valid IPv6 address: fe80::2c02:db79

Some IPv6 addresses aren't global and in those cases need a scope ID to describe their context. These get a '%' followed by the scope ID. For example the previous example with a scope ID of '8' would be: fe80::2c02:db79%8

IPv6 addresses in URIs may appear in the host section of a URI as long as they're enclosed by square brackets. For example: http://[fe80::2c02:db79]/. The RFC explicitly notes that there isn't a way to add a scope ID to the IPv6 address in a URI. However a draft document describes adding scope IDs to IPv6 addresses in URIs. The draft document uses the IPvFuture production from the URI RFC with a 'v1' to add a new hostname syntax and a '+' instead of a '%' for delimiting the scope id. For example: http://[v1.fe80::2c02:db79+8]/. However, this is still a draft document, not a final standard, and I don't know of any system that works this way.

In Windows XPSP2 the IPv6 stack is available but disabled by default. To enable the IPv6 stack, at a command prompt run 'netsh interface ipv6 install'. In Vista IPv6 is the on by default and cannot be turned off, while the IPv4 stack is optional and may be turned off by a command similar to the previous.

Once you have IPv6 on in your OS you can turn on IPv6 for IIS6 or just use IIS7. The address ::1 refers to the local machine.

In some places in Windows like UNC paths, IPv6 addresses aren't allowed. In those cases you can use a Vista DNS IPv6 hack that lives in the OS name resolution stack that transforms particularly crafted names into IPv6 addresses. Take your IPv6 address, replace the ':'s with '-'s and the '%' with an 's' and then append '.ipv6-literal.net' to the end. For example: fe80--2c02-db79s8.ipv6-literal.net. That name will resolve to the same example I've been using in Vista. This transformation occurs inside the system's local name resolution stack so no DNS servers are involved, although Microsoft does own the ipv6-literal.net domain name.

MSDN describes IPv6 addresses in URIs in Windows and I've described IPv6 addresses in URIs in IE7. File URIs in IE7 don't support IPv6 addresses. If you want to put a scope ID in a URI in IE7 you use a '%25' to delimit the scope ID and due to a bug you must have at least two digits in your scope ID. So, to take the previous example: http://[fe80::2c02:db79%2508]/. Note that its 08 rather than just 8.

roundup ip windows ipv6 technical microsoft boring syntax

Vishu and Patent Cube

2007 Nov 28, 5:07Vishu, my ex-office-mate, has left Washington and Microsoft for California and Facebook. Vishu and I shared an office for a while and I really enjoyed it. We were able to distract one another from, and help each other with work. We'd often bounce ideas off of one another, work related or otherwise. For one such idea I recently received a Microsoft patent cube, a small marble cube inscribed with my and my invention's name. There are some photos of other people's patent cubes on flickr. Vishu would have received one for this idea too since we developed the idea and wrote the document about it together, but they wait a long time to send you the cube and he was gone a few weeks before they sent it (don't worry, he got the credit and other rewards though).

A week or two after I got my cube Vishu was visiting the Microsoft campus just before moving his family down with him to California. A bunch of us joined him for lunch that day and it sounds like he's enjoying his new job already. Have fun Vishu!microsoft facebook vishu cube patent nontechnical

Zune Software Update

2007 Nov 19, 3:47I really appreciate that the first gen Zune's get the new Zune's firmware and software. I like the updated Zune software personally because its faster and simpler, has better podcast support, and the whole social thing has is on their website now. So, I guess I like the software because it has new features that should have been there in the first place.

The social thing is like a Zune social network. It uses your Xbox Live friends to seed your Zune friends list, lets you do the expected social network stuff, lets you preview songs, and unlike first gen Zunes which required face to face time with other Zune owners, allows you to send songs to people. It also lets you display your recently played tracks and your favorite tracks, similar to what Last.FM has, via a Zune Card. I like the Zune Card from a technical perspective because it separates the Zune Card view, written in flash from the User Card data which is in XML. I hope they intend to keep the XML available via this UserCard Service because I think there's potential to easily do cool things.microsoft technical music zune social

Easy Come Easy Go

2007 Sep 14, 7:37I previously mentioned how much I enjoyed my new office. Well my team has moved to a new building and although we get more offices total meaning no one on the team has to share an office, this building has less windowed surface area which means less people get window offices. Since I received the window office recently I'm kicked out now in FIFO order. Stacks are so sad.microsoft work personal office nontechnical

Delicious shortcut tag

2007 Apr 8, 3:05Shortcut Tag?
I just saw this on another user's delicious links: a link to ESV search that's tagged with, among other things, "shortcut:esv". When viewed on del.icio.us there's a text box that lets you search using that link. I hadn't seen this before, but it seems pretty cool and I'm surprised I hadn't seen it previously. A delicious post with such a tag ends up looking like the following: I tried searching for information on this and I've found other delicious users doing the same thing, but nothing about the tag itself. If you know any information especially official information from del.icio.us itself please post links in reply to this post. So without further preface here's what I've learned about the del.icio.us shortcut tag.

How-to
To get a search box in your del.icio.us links make a post that satisfies the following requirements:

1. One of the tags must begin with the text 'shortcut:'. You can have more text following that in the tag if you like but it must at least start with 'shortcut:'.
2. The 'url' you post must be a shortcut url rather than an actual URL. It must contain a '%s' with a lowercase 's'. When you enter text into the textbox on the del.icio.us page the text will replace the '%s' after being percent-encoded. For example 'http://www.google.com/search?hl=en&q=%s' is the shortcut url for Google and if you type 'foo bar' into the textbox the URI you will navigate to would be 'http://www.google.com/search?hl=en&q=foo%20bar'.

Complaints
This is neat but I do have a few complaints:

1. The text from the textbox is percent-encoded before replacing the '%s'. Most sites use application/x-www-form-urlencoded which encodes spaces as '+' rather than '%20'.
2. The shortcut url format seems to be taken from Mozilla's Firefox Custom Keywords. Its a shame it wasn't based on something more adaptable like the OpenSearch URL template syntax.
3. A '%s' in the url means technically what you're submitting to del.icio.us isn't a URI as defined by the standard.
4. Allowing text after 'shortcut:' means you can't look at all of a user's shortcut using this tag.

The next step is to create a tool to sync my IE7 search providers with my shortcuts saved to delicious...technical howto tagging tool tag delicious