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Is vfp capable of using fingerprint scanner? 3
- Thread starter Mandy_crw
- Start date
Peace worldwide - it starts here...
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1
- #4
Mike Lewis
Programmer
Mandy,
I'm assuming that you are talking about a scanner that can be plugged into the USB port of a computer - as opposed to one that is built into a device such as a phone. If so, the short answer is Yes. The scanner is just another input device, and there is no reason for VFP not be able to access it.
But I suspect that that answer is not going to help you. What you really need to know is how to interpret the output of the scanner from within your program. This will depend on the type of scanner, but in general VFP will see its output as a raster image - a bit like a photograph of the fingerprint.
So what are you aiming to achieve? Presumably you want to use the scanner as a security device, to verify the identity of the user. To do that, you would need to compare the image generated by the scanner with one that is stored in the computer. For that, you would need specialist software, given that there will always be differences in the two images, caused by differences in orientation and resolution, imperfections in the scanning process, and other issues. In practice, you would not expect an exact match, but rather a percentage confidence level - a number between zero and one hundred which indicates the likelihood of the match.
In short, you need specialist software to interpret the output from the scanner from within your own program. I suspect you will have difficulty finding such software, as scanners are usually sold to manufacturers who build the necessary software into their computers, phones, etc. But I might be wrong about that, so study the documentation that came with the scanner or peruse the vendor's website.
If none of the above answers your question, perhaps you could tell us more about what you are trying to achieve.
Mike
__________________________________
Mike Lewis (Edinburgh, Scotland)
Visual FoxPro articles, tips and downloads
I'm assuming that you are talking about a scanner that can be plugged into the USB port of a computer - as opposed to one that is built into a device such as a phone. If so, the short answer is Yes. The scanner is just another input device, and there is no reason for VFP not be able to access it.
But I suspect that that answer is not going to help you. What you really need to know is how to interpret the output of the scanner from within your program. This will depend on the type of scanner, but in general VFP will see its output as a raster image - a bit like a photograph of the fingerprint.
So what are you aiming to achieve? Presumably you want to use the scanner as a security device, to verify the identity of the user. To do that, you would need to compare the image generated by the scanner with one that is stored in the computer. For that, you would need specialist software, given that there will always be differences in the two images, caused by differences in orientation and resolution, imperfections in the scanning process, and other issues. In practice, you would not expect an exact match, but rather a percentage confidence level - a number between zero and one hundred which indicates the likelihood of the match.
In short, you need specialist software to interpret the output from the scanner from within your own program. I suspect you will have difficulty finding such software, as scanners are usually sold to manufacturers who build the necessary software into their computers, phones, etc. But I might be wrong about that, so study the documentation that came with the scanner or peruse the vendor's website.
If none of the above answers your question, perhaps you could tell us more about what you are trying to achieve.
Mike
__________________________________
Mike Lewis (Edinburgh, Scotland)
Visual FoxPro articles, tips and downloads
Hi Mandy,
As Mike mentions, I want to restate this slightly. Can you give us the problem you want to solve, instead of the solution you are proposing?
Best Regards,
Scott
MSc ISM, MIET, MASHRAE, CDCAP, CDCP, CDCS, CDCE, CTDC, CTIA, ATS, ATD
"I try to be nice, but sometimes my mouth doesn't cooperate.
As Mike mentions, I want to restate this slightly. Can you give us the problem you want to solve, instead of the solution you are proposing?
Best Regards,
Scott
MSc ISM, MIET, MASHRAE, CDCAP, CDCP, CDCS, CDCE, CTDC, CTIA, ATS, ATD
"I try to be nice, but sometimes my mouth doesn't cooperate.
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1
- #6
tomk3
Programmer
Hello,
we use biometric devices (vene, fingerprint, face, signature, voice, walking, ...) in our software.
usually the device gets data ("scan") and build a template ("HASH") from it.
Then you have 3 functions
- Learning
Let the device scan and build a template and assign it to a person
- Identify
a person is scanned (vene,finger,...) and the generated template is compared against other templates in a database.
This is NOT a simple memoa=memob but within the API the template is compared with usually secret algo. against the stored ones.
The API then returns the matching template ("person") or nit found
and/or
- verify
same as identify but much faster.
The generated template is compared only against one stored template returning match yes or no.
So the questions are :
What do you need ?
How much security do you need (is the person alive sensor ,...) ?
Can VFP use the API of the device ?
Devices and API can be very expensive, for example vene apis start from 5.000,- EUR, face regocnition from 12.000,- .
Fingerprint devices with API are MUCH cheaper but MUCH less secure.
Best regards
tom
we use biometric devices (vene, fingerprint, face, signature, voice, walking, ...) in our software.
usually the device gets data ("scan") and build a template ("HASH") from it.
Then you have 3 functions
- Learning
Let the device scan and build a template and assign it to a person
- Identify
a person is scanned (vene,finger,...) and the generated template is compared against other templates in a database.
This is NOT a simple memoa=memob but within the API the template is compared with usually secret algo. against the stored ones.
The API then returns the matching template ("person") or nit found
and/or
- verify
same as identify but much faster.
The generated template is compared only against one stored template returning match yes or no.
So the questions are :
What do you need ?
How much security do you need (is the person alive sensor ,...) ?
Can VFP use the API of the device ?
Devices and API can be very expensive, for example vene apis start from 5.000,- EUR, face regocnition from 12.000,- .
Fingerprint devices with API are MUCH cheaper but MUCH less secure.
Best regards
tom
- Thread starter
- #7
Hi everyone... thank you for all your answers... my application actually get the number from an RFID as an input... then came accross with the usb finger print... is it possible to use the finger print scanner as an input device for my textbox?
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1
- #8
Mandy,
In theory, yes. What what text from a fingerprint are you going to store?
As Mike and others have mentioned, the output of the reader is a type of "raster" file. That doesn't lend itself well to text for anything meaningful.
You actually need to think about 2 things here. 1) How you're going to store the data in the table (i.e. is it a binary field, text field, numeric field, general field, memo field?) and 2) What (if any) type of display of the data do you want/need?
For answering #1, a memo field may well be your best option, and that leads to two possibilities:
1) Store the data directly in the memo field
2) If it's an "image", store a reference (path where the file is store) to the image, and store the image external to the data base. The reason for this is, database corruption (you'd need to use a general field instead of a memo) if you want to store image data. This makes your table BIG FAST, and since you have a 2gb maximum table size, you don't want to store large blob files in the table. It's better to store them external, and use a path reference to them, stored in a memo field.
For the second part, do you want/need to display the captured data? Is there any value in that? Probably not. So a textbox isn't necessary. More likely here you need some kind of API that will analyze data collected from your reader against a saved version of that data. (Fingerprint verification). So there probably is no need (and no meaningful data) to display anyway.
You still haven't really explained why you want the data from the fingerprint reader. Is it an "input device" -- yes it is. But that input is fairly specific in its use. It's not a camera. It's a security measure. I can't think of another reason to use a fingerprint reader.
Best Regards,
Scott
MSc ISM, MIET, MASHRAE, CDCAP, CDCP, CDCS, CDCE, CTDC, CTIA, ATS, ATD
"I try to be nice, but sometimes my mouth doesn't cooperate.
In theory, yes. What what text from a fingerprint are you going to store?
As Mike and others have mentioned, the output of the reader is a type of "raster" file. That doesn't lend itself well to text for anything meaningful.
You actually need to think about 2 things here. 1) How you're going to store the data in the table (i.e. is it a binary field, text field, numeric field, general field, memo field?) and 2) What (if any) type of display of the data do you want/need?
For answering #1, a memo field may well be your best option, and that leads to two possibilities:
1) Store the data directly in the memo field
2) If it's an "image", store a reference (path where the file is store) to the image, and store the image external to the data base. The reason for this is, database corruption (you'd need to use a general field instead of a memo) if you want to store image data. This makes your table BIG FAST, and since you have a 2gb maximum table size, you don't want to store large blob files in the table. It's better to store them external, and use a path reference to them, stored in a memo field.
For the second part, do you want/need to display the captured data? Is there any value in that? Probably not. So a textbox isn't necessary. More likely here you need some kind of API that will analyze data collected from your reader against a saved version of that data. (Fingerprint verification). So there probably is no need (and no meaningful data) to display anyway.
You still haven't really explained why you want the data from the fingerprint reader. Is it an "input device" -- yes it is. But that input is fairly specific in its use. It's not a camera. It's a security measure. I can't think of another reason to use a fingerprint reader.
Best Regards,
Scott
MSc ISM, MIET, MASHRAE, CDCAP, CDCP, CDCS, CDCE, CTDC, CTIA, ATS, ATD
"I try to be nice, but sometimes my mouth doesn't cooperate.
tomk3
Programmer
... just to add :
Think of fingerprint and ask your users. In opposite to vene / face ident,... it is a device which needs direct contact, so cleaning is an issue.
In 2021/2022 fingerprint sensors were banned on customers sites due to corona.
I recommend to search or ask here or in other forums for a device with an API (32bit for VFP), of course available in your country.
You may also select a device, download the api and try / ask.
There are "metalibraries" like GRIAUL (the grfinger.dll) to be used for different devices. They are not cheap but sometimes a licence is delivered with the scanner
There are tools like kodnet or wwdotnetbridge which allow to access .net dlls.
BR
Tom
Think of fingerprint and ask your users. In opposite to vene / face ident,... it is a device which needs direct contact, so cleaning is an issue.
In 2021/2022 fingerprint sensors were banned on customers sites due to corona.
I recommend to search or ask here or in other forums for a device with an API (32bit for VFP), of course available in your country.
You may also select a device, download the api and try / ask.
There are "metalibraries" like GRIAUL (the grfinger.dll) to be used for different devices. They are not cheap but sometimes a licence is delivered with the scanner
There are tools like kodnet or wwdotnetbridge which allow to access .net dlls.
BR
Tom
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