Thread: Need help related to further encrypting and decrypting media file

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    Need help related to further encrypting and decrypting media file

    I am working on a project wherein a new hardware is to be created which kinda acts like a dvd player...This new hardware will contain the operating system and media player. Video files will be played using this hardware. But those video files will be further encrypted...and can be decrypted only through the hardware...so that they can be played only on our hardware...so say for example we use mkv file format...we shall further encrypt it....and customize the media player to first use our decryption algorithm and only then use the mkv
    decoder to further decrypt it.
    This is my first assignment related to any media players and hence need help with the following:-

    1>Which is possibly the best file format and best media player that can serve our purpose?....We have thought of mkv + vlc...pls suggest otherwise..
    2>How can I add my encryption to the file?
    3> What other tools will I require?

  2. #2
    Registered User VirtualAce's Avatar
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    Talking about encryption and decryption could actually be illegal for some members here. Having looked into OpenSSL I found that if someone from the USA contributes to a discussion, code base, or any other form of communication in which encryption/decryption technology is shared or passed along they could be subject to prosecution under US cryptography export laws.

    That being said I'm not sure which is the best format. It depends if you are focused on quality or size or a mix. You can encrypt the file format anyway you feel is necessary using your own algos or those found on the internet.

    I'm not sure what other tools you would need.

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    Just a pushpin. bernt's Avatar
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    How can I add my encryption to the file?
    Probably a stream cipher for video. It's fast and easy and you can decode as you need the data.

    With that said,
    Which is possibly the best file format and best media player that can serve our purpose?....We have thought of mkv + vlc...pls suggest otherwise..
    I'd go with mpeg for two reasons:
    1) MPEG is ubiquitous. It's already used for DVDs and pretty much every computer on the planet is going to be able to play MPEG without having to download additional codecs. (Not that that matters since you're trying to limit playback to a certain machine, but still...)
    2) If you're decoding full screen video in real time, that's going to take up a lot of processor power, and there is MPEG-decoding hardware available to take some of the burden off the main processor. It's commonplace in DVD players and is now being used in mobile devices to save battery life.
    Last edited by bernt; 06-29-2010 at 08:24 PM.
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    Registered User kryptkat's Avatar
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    I am working on a project wherein a new hardware is to be created which kinda acts like a dvd player...This new hardware will contain the operating system and media player. Video files will be played using this hardware. But those video files will be further encrypted... ==> and can be decrypted only through the hardware... <== so that they can be played only on our hardware...so say for example we use mkv file format...we shall further encrypt it....and customize the media player to first use our decryption algorithm and only then use the mkv
    decoder to further decrypt it.

    first .... anything can be decrypted by hardware or software.
    second.... the nand gates and nor gates <chips> used would be quite expensive and only have one algorithm. software is more flexible and CHEEPER !
    third.... if you are looking to make money from some video you made your best bet is to run it on a projector and have a room set up like a standard movie theater setting ie collect your money from viewers as they enter room a and from room be project the movie. <no enc nessessary>
    fourth.... the extra ram you would need for the hard ware also adds to the cost.

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    Software can do everything. The only reason to use hardware is to speed it up, which may indirectly cut cost and power requirement by requiring slower CPU.

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    Thanks guys...
    The media files made by us will be sold on a pen drive and that can be played only on the hardware sold by us...Also there are a few new accessoriess added to the hardware...
    and hence the hardware device..

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    Woof, woof! zacs7's Avatar
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    Why not do something "crazy" then, instead of encrypting it, just reverse the video format, so the header is at the end, and the frames come before it? .

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    Registered User kryptkat's Avatar
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    The media files made by us will be sold on a pen drive and that can be played only on the hardware sold by us...Also there are a few new accessoriess added to the hardware...
    and hence the hardware device..
    what you are proposing has already been done many times in one form or another and ends up the same. let meow direct your attention to divx. this first came out and you only could play the things that had their special discs and players. but it was cracked so that you do not need the hardware and can play the discs on the pc dvd drives with the software as many times as you like <cracked version> . what "new accessories" ? a dongle ? others have done that same thing .... suit yourself.


    DivX - Wikipedia, the free encyclopedia

  9. #9
    (?<!re)tired Mario F.'s Avatar
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    Quote Originally Posted by kryptkat View Post
    what you are proposing has already been done many times in one form or another and ends up the same. let meow direct your attention to divx. this first came out and you only could play the things that had their special discs and players. but it was cracked so that you do not need the hardware and can play the discs on the pc dvd drives with the software as many times as you like <cracked version> . what "new accessories" ? a dongle ? others have done that same thing .... suit yourself.
    I felt like ignoring this post. But the error is so gross, I think for the benefit of future mankind who may stumble upon this thread, it should be corrected.

    DIVX is not the same of DivX. The first was a rental system, the latter (for the purposes of this context) a codec. And it says that much in the link you posted. The correct link is instead: DIVX (Digital Video Express)

    Now for the crack talk regarding Digital Video Express. Where you really messed it up.

    DIVX could be cracked two ways: decrypting the disk contents or tampering with the DIVX player. The first option would be the most rewarding, since someone could rent a movie and supposedly make a copy for storage (similar to the type of copyright infringement traditional movie rental is very liable to) and read that copy on any player or the computer. The second option was less rewarding. It would essentially allow the user to bypass the watch limit and see the movie as many times as they liked, forever. But they would need the DIVX player.

    But DIVX was really never cracked. It had a very low adoption which essentially killed it just a few months after release. The bad press was so overwhelming, the business imploded. There was no real time, or a user base big enough, that could justify the hackers community interest for long (there was some, but it lived and died during the beta stages of the product). Then there was something else:

    The option of decrypting the disks was tremendously difficult to achieve. The contents were protected by a Triple DES algorithm which was then (and still is today) very hard to break. And because of the way the rental system worked, new keys could be uploaded the player through the phone line, virtually every day. So thinking of trying to tamper with the hardware to learn the key would be useless. (Eventually keys could in the future even be served by the phone line, on a play basis. The hardware would not store anything).

    The hardware was the real hope. But, apart from some successes (as seen on the link above) during the beta stages, the matter of fact is that, those were problems that were easily fixed before the release date. And it was really the least interesting option. Firmware updates would be a constant once the business started. And this too would make most successful hacking short lived.

    It was a horrible idea and a horrible product. It was soon made obvious it couldn't outlive the public cry. But it surely was then, and still is to this date, the most effective copyright protection mechanism ever developed for the movie industry. The combination of closed hardware, encrypted content and a phone line was tremendously effective. I guess the product didn't live long enough for us to tell a different story. But you say it was cracked. And it definitely was not.
    Last edited by Mario F.; 07-11-2010 at 10:32 PM.
    Originally Posted by brewbuck:
    Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.

  10. #10
    Registered User kryptkat's Avatar
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    well.... umm....

    this is the one i was referring too....
    DIVX was a rental format variation on the DVD player in which a customer would buy a DIVX disc (similar to a DVD) for approximately US$4, which was watchable for up to 48 hours from its initial viewing. After this period, the disc could be viewed by paying a continuation fee to play it for two more days.
    famous last words ?
    DIVX could be cracked two ways: decrypting the disk contents or tampering with the DIVX player.

    ....


    But DIVX was really never cracked.
    i can know of two or more ways you did not mention.<sniff sniff pouttie lower lip> in addition to the two you did mention. or you could do it the easy way like most scriptkiddies and ninety percent of most divx owners <at least the ones i knew> knew of plugging the divx player directly into a standard vcr recording it the first time it plays on to a vcr tape so they could watch it as many times as they like or whenever they wanted.

    And because of the way the rental system worked, new keys could be uploaded the player through the phone line, virtually every day. So thinking of trying to tamper with the hardware to learn the key would be useless. (Eventually keys could in the future even be served by the phone line, on a play basis. The hardware would not store anything).
    you said " new keys could be uploaded the player through the phone line virtually every day" to a non rewriteable video disc ? <sniff sniff pouttie lower lip> i believe it was the same key up loaded each time for "that" movie title disc and each different movie title had a different key. the hardware dumped the key and did not keep it. if you collected the key as it comes in then you could play it anytime you like with that key. i have a few issues with this system <disc and hardware and phoneline>

    first issue is privacy. they know what you are watching and when. they will know how often you watch which movies. a data base that they will keep on your viewing habbits. and how much money you spend on it.
    second issue is paying for the same movie again and again be it rented or purchase. there will be a point were a number of plays will equal the cost of the purchase of a normal dvd.
    third issue is phonelines with hardware. have you ever received the busy signal and can not get through ? if millions of users in each city all call at nearly the same time jamming the phone system of the key server it will be a long wait until you get a "new key" <the same key for that title>

    i should have posted both links i had but i just posted the one. we are trying to guide the op in the right direction. for example if the op pen drive cost $15 purr unit for the op to set up the component population machinery to produce a million of the op pen drives units it would cost 15million dollars plus the $200,000.00 <or whatever the current setup fee is> by using software as i suggested the op would save $15,200,000.00 purrhapps i should get a consultation fee of say 20% for saving the op $15,200,000.00 ?

    if i had to venture a guess mario f i would guess that you are between 15 and 18 percent of gewggles search engine traffic. like the cws file that lootube is using....their new player. if i let it run the way it wants to play it opens up a huge security holes much like activex. it is more culture .... like search engine junkies are now about the same as video game addicts. there was a good talk show topic on video game addiction the other night. some times it is purrspective for example did you see martha stuarts cat show ? the animal lover culture thinks kissing their pets which are family members is ok but if some one from the lawmaker culture sees that they would say "arrest that woman for having bestially relations with a cat because kissing is considered in the eyes of the law culture a sexual act"

    if the op wants to take the advice that is their purragitive. i say just stick the fbi warning that you will be fined $200,000.00 dollars on the front of the video and be done with it. you will make money.

  11. #11
    (?<!re)tired Mario F.'s Avatar
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    Ugh!

    I'm having an headache.
    Originally Posted by brewbuck:
    Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.

  12. #12
    Registered User VirtualAce's Avatar
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    Agreed. The shift key is just to the left of the Z on the left side and just to the right of the question mark on the right side. The punctuation marks can normally be found on the number keys at the top of your keyboard. It might be nice to utilize those in the future.

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    Registered User kryptkat's Avatar
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    two feline technically astute reading everyday we tend to see and do a lot of this stuff and have a better feel for what works. there are already several way to get around the hardware which will be similar to getting around your pen drive hardware short of taking a video camera in to a movie theater and recording the movie <which ends up shaky like the blair witch>. i believe enjoying what you do is more important than making money.

    i was only trying to show you how fast the costs fees and commissions can add up as an example only. i thought if you looked at it from a monetary point of view your business sense would engage.


    greed is why most get caught. they start by making a few hundred thousand copies and trying to sell them. then the business owners get greedy and try to put security measures on their products <while they are making huge amounts of money> a loose - loose situation. the warning seems to be the best compromise. i say that because in this economy i think the extra cost of hardware would be a selling point you should seriously consider.

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