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Comments · 1,277

  1. Re:MPEG-2 does HD fine on China to Promote Own Alternative to DVDs, EVD · · Score: 1

    I was under the impression MPEG-2 did not scale to higher resolutions nearly as elegantly as the MPEG-4 class of codecs, at least in terms of marginal bandwidth.

    Now, if you've got the bits, that's another story.

    Am I wrong? (You, after all, did write the book on the subject *smiles*).

    --Dan

  2. Re:EVD sounds superior on China to Promote Own Alternative to DVDs, EVD · · Score: 1

    China's going to create HDTV VCR's. Interesting.

  3. Video Codec Appears To Be VP5 & VP6 on China to Promote Own Alternative to DVDs, EVD · · Score: 3, Informative

    I looked into this a bit. Apparently Chinese manufacturers are starting to balk at the ~$350M going out to Japanese DVD patent holders, and the government is listening.

    Remember -- fifty years ago, Japan tried to colonize Southeast Asia. Southeast Asia is still pissed.

    Anyway, the video codec appears to be On2's VP5 and VP6 -- which, being much newer codecs than MPEG-2, support HDTV resolutions and DVD bitrates -- supposedly with quality as good, if not better, than Microsoft's solution. (Caveat: I was not impressed with VP3, the algorithm open sources by On2 and being tweaked heavily into Ogg Theora.) Not said is what's being used for the audio codec. While audio compression and video compression are two very different things, it's problematic when the two are grown utterly separate from one another. DVD has this problem -- MPEG-2 and AC3 (Dolby Digital) have slightly different frame sizes, making it much more awkward to edit accurately.

    Yours Truly,

    Dan Kaminsky
    DoxPara Research
    http://www.doxpara.com

  4. There's No Such Thing As 9 Million Hits on Why Microsoft Wants to Buy Google · · Score: 2, Interesting

    The maximum number of hits a particular search can sustain is between 5 and 100.

    This was a great surprise to the engineers building search engines -- the original problem was, how do we find particular keywords across hundreds of millions of documents? This was solved relatively trivially -- index by keyword, and distribute the search space across the memory of many, many machines. All of the sudden, it became apparent that search had much less to do with how much you could search and much more to do with which results came up first.

    That's a much harder problem -- fundamentally, without the user telling you what he wants, how can you figure out what he's most likely to desire? This actually uses artificial intelligence techniques, much to the consternation of the eternally discredited AI folk who point out that "the moment AI becomes useful, it ceases to be called AI" (which is true). It's AI because you effectively need to programmatically derive what an intelligent surfer is most interested in, as an abstract subject instead of a concrete phrase. Google gets alot of credit for their Pagerank algorithm, which uses links from other sites to weigh which links are more "authoritative" than others, but interestingly enough their system is noticably robust even without outside links. Corporate websites all tend to run 1998-era search engines -- all quantity, no quality (and in this case, quantity has no quality all its own). Some time ago, I worked at a massive company that was testing Google for internal searches. Corporate web pages are far less cross-linked than the web itself. But Google-internal worked just like...well, Google :) So there's some really smart AI there.

    Anyway, as I've said before, MS can't buy Google; they'd just create the market segment of "what Google used to be". Speaking as someone who has a healthy respect for MS as a company, they've simply burned through too much goodwill for people to trust their search results as authoritative. Yes, mysql only gets a few hits on MSN search. So does pancakes, and I doubt MS is part of the great Waffle Iron Conspiracy.

    Yours Truly,

    Dan Kaminsky
    DoxPara Research
    http://www.doxpara.com

  5. Re:It's not what, it really is who on Microsoft Looks At Other Search Engines · · Score: 1

    In summary, Microsoft ain't any worse than AT&T, McDonald's or Toyota to the average jerk.

    Except that's not true. It's alot easier to imagine life without AT&T, Toyota, and especially McDonalds than it is to imagine using a computer that isn't running Microsoft. You've got to understand -- I saw our labs at school; people would mill about for a half hour waiting for a PC while an entire line of iMacs was free. That kind of...dependancy...engenders a certain kind of further dependancy on image.

    The average jerk doesn't necessarily love Microosft, but they do need them. You may be underestimating the depth of doubt MS (somewhat unfairly) suffers.

    If you think XBox is just about video games, you're not thinking big enough.

    --Dan

  6. Small Note on FCC Adopts Broadcast Flag Scheme · · Score: 1

    Um, content providers?

    Releasing a 1970-era TV experience (pre-VCR!) into the 2005 market is not exactly the best way to make a buck.

    --Dan

  7. Re:It's not what, it really is who on Microsoft Looks At Other Search Engines · · Score: 1

    Don't be so sure. It's not just the Linux zealots who look askance at a donation; a surprising proportion of IT people would doubt a Microsoft donation much more than an Apple one.

    This happens despite the fact that even the Apple supporters admit donations are a naked attempt at guaranteeing users in the future!

    You must understand, I'm writing this message from a machine running XP. I'm quite impressed with the technical work that Microsoft has done, thank you very much. But they really do have an image problem -- and image can and does trump a surprising amount of facts.

    Now if you want me to get into a rant, tell me that this behavior is irrational ;-)

  8. It's not what, it really is who on Microsoft Looks At Other Search Engines · · Score: 5, Insightful

    OK.

    First of all, Google is something different. 75% of web referrals come from it. 75%.

    This is sort of sad in one interesting way -- The Internet Archive is complete. Without the State of Google at any given time, the archive is incomplete. Archiving the state of Google...

    Now that's a hard problem.

    Google's success did come from their ease of use and their several-order-of-magnitude improvement over their predecessors (Altavista, mainly, but Hotbot too). The Google challenge really was incredible -- "Put in what you're looking for. It'll be one of the top links. Be as obscure as you want." And they won the challenge.

    I'm Feeling Lucky really is an amusingly cocky creation -- "our top link is likely enough to be the right one that we don't even need to show you a list."

    It works.

    Anyway, adoption was driven by the order of magnitude improvement, and is now very hard to clone -- going from 10 to 1000 is easier than 1000 to 1000000, by far. It's not enough to be equal - - you need to be better, at a degree than is actually possible for search to provide.

    But once Google was adopted, it needed to stay in a position of power. Here's where the "niceness" of Google -- "don't do anything evil" -- won. Combine a Stanford Geek lackadasiacal attitude to all corrupting influences, no details about financial hardship, and massive street cred, and you get the snowball that brought us to 75% today.

    Google was even allowed to sell ad space, given the "reluctance" and "geekily targeted" (has anyone else made targeting not seem like a privacy violation?) nature of their system. It's very interesting the nature of identity for a particular behavior -- basically, we assign motive to all actions that we see, as a mechanism for predicting future behavior. Google has motives that align with our interests -- a high quality, stable, authoritative source for what we're looking for. So it gets away with things that...say...Microsoft can't.

    Microsoft would destroy the Google brand. They can't even donate money to schools without people thinking they're trying to brainwash kids! Meanwhile, Apple's been donating systems to grade schools since all of us were in them. The idea of a non-independent Google is fundamentally uninteresting, and really does create a new market segment:

    What Google Used To Be.

    Obviously, this is in nobody's interest, except maybe for other search engines. So shockingly enough, no sale.

    Yours Truly,

    Dan Kaminsky
    DoxPara Research
    http://www.doxpara.com

  9. s/Presentatin/Presentation on Integrating A GUI Into An Existing Medical Device · · Score: 1

    i should have used preview.

  10. Presentatin vs. Data on Integrating A GUI Into An Existing Medical Device · · Score: 1

    OK, alot of people really aren't understanding why this is very cool and very, very important.

    You really, really don't want UI code interfering with important things, like not killing people. Ideally, there's as wide a gap between the two functions as possible.

    Realistically, the C/ASM coders have had to implement things like keypad pollers and shape routines in the same codebase as they do important, non-patient-killing things. This very much meant a failure in one killed the other.

    Offloading the entire UI onto a separate chip, that happens to be very easily programmable by people who have nothing to do with life critical code, does something very important:

    It creates a completely new execution environment that, if it crashes, doesn't kill anyone.

    For decades, computer security was about mainframes, with complex and ultimately buggy rules about memory classifications and data transfer. Oh, how they toiled to prevent users from leaking data between eachother.

    Then the Internet came along...and gave one computer to one user...and another computer to the other. That's one way to segment RAM.

    Yours Truly,

    Dan Kaminsky
    DoxPara Research
    http://www.doxpara.com

  11. A Glorious TCP Hack on Integrating A GUI Into An Existing Medical Device · · Score: 1

    OK, so the definitive book on the topic of Embedded TCP/IP is almost certainly TCP Lean, by Jeremy Bentham. Any book that explains Ethernet with an O-scope trace is alright by me :-) Anyway, Jeremy documented one of the coolest TCP hacks ever. Check it out:

    So, HTML is really quite useful for embedded devices -- GUI toolkits are quite heavy, and HTML nicely and consistently exports that weight to the client. Now, that'd be the end of the story, except...we're not talking about devices that can't render a GUI, we're talking about devices without enough operating RAM to store a single packet. Ethernet, IP, TCP, HTTP, HTML...each field of each protocol needs to be written, one by one, in order, into the network card's send buffer. And once it's in -- no getting it back out, at least not quickly.

    You'd think this wouldn't pose a problem...just calculate the values as needed and spit them out on the fly. But what about checksums? It's one thing to insert an IP address or a TCP source port, but checksums aren't independent, i.e. they depend on the IP addresses, the source ports, and all the other fields in the packet, including the payload itself! They (both IP and TCP have one) are "summary" values that seemingly require passing over each byte in the entire packet, running a transform given all that data, and outputting a two byte value.

    What to do?

    Short answer: Do it backwards...or more accurately, do it later. If you can't make the checksum match the payload...make the payload match the checksum! Watch:

    The particular checksum used by IP and TCP is almost literally a checksum -- all the bytes are added, and there's your sum. This has the convenient property of being easily reversable: If one byte is +10, another byte can be -10 and the sum will add up the same. So, you basically calculate the checksum given some "prototype values", and when you actually find the real values, you measure the offset between them and the prototype and take note of it.

    Finally, when your normal payload is done, you add just a little more...you add additional data that forces the payload to adapt to the prototypical checksum. And where, might you ask, would you add this data?

    HTML comment. We were talking about web pages, after all.

    Uber. Bentham rocks.

    Yours Truly,

    Dan Kaminsky
    DoxPara Research
    http://www.doxpara.com

  12. Re:Just like a video game on Preparing for the DARPA Autonomous Vehicle Challenge · · Score: 1

    Vibration control is a prerequisite to any successful camera system. Hell, we've got one, it's called a neck :-)

    >60fps cameras may also be of use, especially with hardware to realtime integrate each of the shaking images. The fact that this is almost certainly going to be a day drive helps _alot_.

    Focus is easy from a distance, and up close, you can actually do rangefinding based on standard autofocus techniques. Even a blurry image of a fence going by will get significantly darker as focus is corrected.

    I'd worry more about night driving than fences.

    The hard part is solving all these problems at once. I'm personally convinced that every car that's preloaded the state of the course and expects to be able to make decisions based on it will fail horrifyingly. A car that deploys a camera on a kite, alternatively, would look ridiculous but drive surprisingly well.

    --Dan

    --Dan

  13. Re:Just like a video game on Preparing for the DARPA Autonomous Vehicle Challenge · · Score: 2, Insightful

    How do you determine if there is an object, or it is just mud on the camera?

    Short answer: Saccades.
    Longer answer: Put a motor on your camera that allows limited angular motion. Put teflon-coated plexiglass in front of the camera (probably with a wiper). Saccade. Check angular parallax.
    Alternative Answer: Dual cameras.

    How do you detect dust and filter that out?

    Do horrible things to shadow elimination code.

    How do you detect a fence - the links are generally too small to be picked up on the camera until you are very close.

    See if you can find a digital camera vendor that will let you hack their firmware. Take 5mpix scans, have the camera output regions with consistent high frequency high contrast shifts.

    Much better is to do what people do, and look for the posts between fences.

    I don't think reflectance will be helpful for this.

    How do you detect water?

    I do think reflectance will be helpful for this.

    A bigger problem is that people are trying to do way too much with GPS...GPS ultimately says what _was_. Using GPS to avoid driving into a lake is a good way to drown.

    Is there a mandatory minimum size for the cars?

    --Dan

  14. FCC Disabling VCRs in 2006 on Broadcast Flag All But Approved · · Score: 4, Insightful

    Analog transmission stops in 2006.

    Anything that lets VCRs work will have to respect the broadcast flag (i.e. will have to fail).

    Nothing will air with the broadcast flag disabled. This includes news.

    Ergo, it seems perfectly reasonable to claim VCR's are being effectively banned between the next two presidential elections.

    --Dan

  15. Re:BIAA - Re:Trumping Capitalism?? on For Americans, Imported Textbooks Can Be Cheaper · · Score: 1

    Reference?

    Too interesting not to know more!

    --Dan

  16. Re:No Receipts to Voters! on E-Voting Companies Answer Critics With ... Spin · · Score: 1

    If a voter can prove to themselves they voted a certain way, they can prove the same to someone else.

    If they can fake a proof to someone else, they can fake a proof to everyone else. Even if the system has some key that appears to show a fake proof to be fake (an interesting model, to be sure), the fact remains you can have a voter quite strenuously lying about the results of their vote (the "having your cake and eating it too effect") thus calling the entire election process into question.

    I'm a moderately experienced cryptographer, incidentally. There are cryptographic tools that can help, but the fundamental risk model (self-auditing leads to vote selling which destroys the validity of an election) does not lend itself well to cryptographic remediation.

    --Dan

  17. Re:No Receipts to Voters! on E-Voting Companies Answer Critics With ... Spin · · Score: 1

    Sure, you can bribe someone all you want.

    If their actual vote is secret, the person is still free to vote for whoever they want -- and then to lie about it to the briber.

    Not enforceable, not reliable.

    --Dan

  18. No Receipts to Voters! on E-Voting Companies Answer Critics With ... Spin · · Score: 4, Insightful

    No!

    It's not that _we_ want paper receipts!

    It's that we want the voting infrastructure to maintain an audit trail.

    Voters getting receipts directly allows for vote selling, which as another poster pointed out, is not limited to monetary compensation but includes anything people are willing to sell a vote for (health, job security, etc.)

    The purpose of an election is not to determine a winner but to make everyone agree on who lost. If the losing side can say, "Sure, people voted for Bob, but it was under duress and thus didn't count", people fail to agree and fealty does not transfer.

    Since we have elections precisely to avoid the violence that normally accompanies a transfer of power, this is not a small matter.

    Yours Truly,

    Dan Kaminsky
    DoxPara Research
    http://www.doxpara.com

  19. Re:Proof to voter versus buyer on Diebold Issues Cease and Desist to Indymedia · · Score: 1

    AC, you missed a rather critical element:


    This hash is printed and/or emailed to a voter-defined email address


    There's some really good crypto that can be designed that meets the required needs -- particularly involving "windowing" approaches to secret key material. But any solution that doesn't have a trustable audit trail attached to it is corrupt by default -- not because of who runs it, but because it fails to meet the single requirement of an election: Not to determine who won, but to make everyone agree on who lost.

    --Dan

  20. Re:Not anonymous on Diebold Issues Cease and Desist to Indymedia · · Score: 1

    If I can generate false proofs, I can falsely question the integrity of an election.

    If I cannot generate false proofs, people have to believe me when I say my vote was miscounted. But then I can easily sell my vote.

    --Dan

  21. Re:Not anonymous on Diebold Issues Cease and Desist to Indymedia · · Score: 1

    All of these are examples of votes getting purchased. Whether a vote buys money (which may be spent on, say, food for a baby), continued employment, intact kneecaps, or a temporary reprieve from domestic violence, fundamentally the wish of the voter is superceded by survival needs.

    Again. Failing to understand the problem is why so many people keep solving it wrong.

    --Dan

  22. Not anonymous on Diebold Issues Cease and Desist to Indymedia · · Score: 4, Insightful

    The fundamental problem is that it needs to be impossible for me to prove to a vote buyer that I voted one way or another.

    If I can prove to myself my vote was counted a certain way, so too can it be proved to others. And then votes get bought.

    This is a _hard_ problem, and alot of it comes from misunderstanding the nature of it.

    --Dan

  23. The Obligatory Anti-Troll Response on Send an Open Source Project to COMDEX · · Score: 0, Offtopic

    With Windows, you can't touch anything up, no matter what.

    With Linux, you don't have to, but have the opportunity to if you like. And as long as the changes aren't publically released in any form, you still don't have to release changes.

    Not even Microsoft makes rights claims on software compiled with their tools. Why would you expect GCC to?

    --Dan

  24. Yeah right on FCC Considers Mandating HDTV Copy Protection · · Score: 2, Insightful

    Stop the HDTV push?

    And give up all that money from spectrum allocation and sales?

    Sorry, can't stop laughing. Um no.

    --Dan

  25. Re:Tom Baker Selling Crappy Products on a crappy s on Eddie Izzard As ... Doctor Who? · · Score: 1

    Obviously not a man who Respects The Pig.

    --Dan