hi i would like to know if a digital signal processor can be used to implement string matching algorithms?like boyer moore, etc..or what is the equivalent that i used for string matching on ADSP processor Thanks
can DSP be used for text/string matching
Started by ●March 11, 2007
Reply by ●March 11, 20072007-03-11
dew wrote:> hi > i would like to know if a digital signal processor can be used to > implement string matching algorithms?like boyer moore, etc..or what is > the equivalent that i used for string matching on ADSP processor > ThanksDSP chips' CPUs are optimized for processing digital data in several ways. Their peripheral devices, off-chip access standards, interrupt structures, and more are likewise specialized. Nevertheless, they can compute any algorithm so long as code and data both fit into available memory. I'm curious: what string-matching application would be well served by a processor specialized for -- and perhaps encumbered with -- other uses? Jerry -- Engineering is the art of making what you want from things you can get. ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
Reply by ●March 11, 20072007-03-11
On Mar 11, 8:55 pm, Jerry Avins <j...@ieee.org> wrote:> dew wrote: > > hi > > i would like to know if a digital signal processor can be used to > > implement string matching algorithms?like boyer moore, etc..or what is > > the equivalent that i used for string matching on ADSP processor > > Thanks > > DSP chips' CPUs are optimized for processing digital data in several > ways. Their peripheral devices, off-chip access standards, interrupt > structures, and more are likewise specialized. Nevertheless, they can > compute any algorithm so long as code and data both fit into available > memory. > > I'm curious: what string-matching application would be well served by a > processor specialized for -- and perhaps encumbered with -- other uses? > > Jerry > -- > Engineering is the art of making what you want from things you can get. > =AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF==AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF= =AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF Thank you for the reply.I am actually jus experimenting with snort IDS.and have been trying to see if the pattern matching module can be implemented on hardware.besides,(obvious from my question) that i am a newbie in DSP, have been trying to find out from the web how string manipulation and matching will take place on a DSP.Thanks a lot for the reply
Reply by ●March 11, 20072007-03-11
On Mar 11, 11:36 pm, "dew" <ame2...@gmail.com> wrote:> On Mar 11, 8:55 pm, Jerry Avins <j...@ieee.org> wrote: > > > > > dew wrote: > > > hi > > > i would like to know if a digital signal processor can be used to > > > implement string matching algorithms?like boyer moore, etc..or what is > > > the equivalent that i used for string matching on ADSP processor > > > Thanks > > > DSP chips' CPUs are optimized for processing digital data in several > > ways. Their peripheral devices, off-chip access standards, interrupt > > structures, and more are likewise specialized. Nevertheless, they can > > compute any algorithm so long as code and data both fit into available > > memory. > > > I'm curious: what string-matching application would be well served by a > > processor specialized for -- and perhaps encumbered with -- other uses? > > > Jerry > > -- > > Engineering is the art of making what you want from things you can get. > > =AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF==AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF= =AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF> > Thank you for the reply.I am actually jus experimenting with snort > IDS.and have been trying to see if the pattern matching module can be > implemented on hardware.besides,(obvious from my question) that i am a > newbie in DSP, have been trying to find out from the web how string > manipulation and matching will take place on a DSP.Thanks a lot for > the replyAre there any resources for me to start with about DSP string processing,etc.
Reply by ●March 11, 20072007-03-11
dew wrote:> On Mar 11, 8:55 pm, Jerry Avins <j...@ieee.org> wrote:...>> I'm curious: what string-matching application would be well served by a >> processor specialized for -- and perhaps encumbered with -- other uses?> Thank you for the reply.I am actually jus experimenting with snort > IDS.and have been trying to see if the pattern matching module can be > implemented on hardware.besides,(obvious from my question) that i am a > newbie in DSP, have been trying to find out from the web how string > manipulation and matching will take place on a DSP.Thanks a lot for > the replyDSPs are complete Turing equivalents and can run any algorithm, as I wrote. They often run without an operating system and rarely have hard disks. They are almost always embedded in such specialized devices as modems, cell phones, and power-line monitors. It is not the instruction set that constrains what it is reasonable to run on them, but their operating environment. Jerry -- Engineering is the art of making what you want from things you can get. ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
Reply by ●March 11, 20072007-03-11
On Mar 11, 1:38 pm, "dew" <ame2...@gmail.com> wrote:> > Are there any resources for me to start with about DSP string > processing,etc.What do you mean by "DSP string processing"? Just to clarify a bit, what people call "DSP chips" come with dedicated hardware to do vector multiplication and convolution efficiently and quickly. In order to do so, they typically have a pipelined architecture. This means that they are meant to do vector multiplication and convolution on fairly long vectors or signals. This means that they are not well-suited for executing logical decision-making, because of the pipelining. Like Jerry said, it does not mean that it's not possible, but you're better off using a general processor. So if your "string processing" includes many vector multiplies and convolution, great. If you are thinking "string processing" as in "string matching", you're looking in the wrong place. Hope that helps, Julius
Reply by ●March 11, 20072007-03-11
On 11 Mar 2007 11:38:10 -0700, "dew" <ame2005@gmail.com> wrote:>On Mar 11, 11:36 pm, "dew" <ame2...@gmail.com> wrote: >> On Mar 11, 8:55 pm, Jerry Avins <j...@ieee.org> wrote: >> >> >> >> > dew wrote: >> > > hi >> > > i would like to know if a digital signal processor can be used to >> > > implement string matching algorithms?like boyer moore, etc..or what is >> > > the equivalent that i used for string matching on ADSP processor >> > > Thanks >> >> > DSP chips' CPUs are optimized for processing digital data in several >> > ways. Their peripheral devices, off-chip access standards, interrupt >> > structures, and more are likewise specialized. Nevertheless, they can >> > compute any algorithm so long as code and data both fit into available >> > memory. >> >> > I'm curious: what string-matching application would be well served by a >> > processor specialized for -- and perhaps encumbered with -- other uses? >> >> > Jerry >> > -- >> > Engineering is the art of making what you want from things you can get. >> > ����������������������������������������������������������������������� >> >> Thank you for the reply.I am actually jus experimenting with snort >> IDS.Snort IDS? What is that?>> and have been trying to see if the pattern matching module can be >> implemented on hardware.besides,(obvious from my question) that i am a >> newbie in DSP, have been trying to find out from the web how string >> manipulation and matching will take place on a DSP.Thanks a lot for >> the reply > >Are there any resources for me to start with about DSP string >processing,etc.If you're looking to do things in the C the standard C-language string.h header file, DSP's can generally do it (because there are C compilers for most all DSP's), but there is no special hardware for string processing in DSP's, and they would do it no better than standard, "mainstream" processors. If text string processing is the only "special" thing the processor would be doing, you would probably be better off using a "standard" processor. If this has something to do with optical character recognition (OCR), then that's another matter, but I still offhand don't see where DSP would have a particular advantage over standard processing.
Reply by ●March 12, 20072007-03-12
dew wrote:> hi > i would like to know if a digital signal processor can be used to > implement string matching algorithms?like boyer moore, etc..or what is > the equivalent that i used for string matching on ADSP processor > ThanksYou can implement any algorithm on the general purpose DSP. However using DSP for the string manipulation is generally not a good idea. Most of the DSPs can't directly manipulate with bytes; the minimum unit is word. The address space is limited, and there can be many other architectural limitations. This will result in a huge and slow code. Vladimir Vassilevsky DSP and Mixed Signal Design Consultant http://www.abvolt.com
Reply by ●March 12, 20072007-03-12
Ben Bradley wrote: ...> Snort IDS? What is that?http://linux.cudeso.be/linuxdoc/snort.php ... Jerry -- Engineering is the art of making what you want from things you can get. ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
Reply by ●March 12, 20072007-03-12
T24gTWFyIDEyLCA5OjI1IGFtLCBKZXJyeSBBdmlucyA8ai4uLkBpZWVlLm9yZz4gd3JvdGU6Cj4g QmVuIEJyYWRsZXkgd3JvdGU6Cj4KPiAgICAuLi4KPgo+ID4gICAgU25vcnQgSURTPyBXaGF0IGlz IHRoYXQ/Cj4KPiBodHRwOi8vbGludXguY3VkZXNvLmJlL2xpbnV4ZG9jL3Nub3J0LnBocAo+Cj4g ICAgLi4uCj4KPiBKZXJyeQo+IC0tCj4gRW5naW5lZXJpbmcgaXMgdGhlIGFydCBvZiBtYWtpbmcg d2hhdCB5b3Ugd2FudCBmcm9tIHRoaW5ncyB5b3UgY2FuIGdldC4KPiCvr6+vr6+vr6+vr6+vr6+v r6+vr6+vr6+vr6+vr6+vr6+vr6+vr6+vr6+vr6+vr6+vr6+vr6+vr6+vr6+vr6+vr6+vr6+vrwoK VGhhbmsgeW91IGFsbC5JIGRvbiB0aGluayB0aGUgc3RyaW5nIG1hdGNoaW5nIG9uIGEgRFNQIGlz IGEgd2lzZSBpZGVhCnRoZW4uCg==