fingerprint

问题 I am working on an app where I use fingerprint. Everything seems to be good but when I debug my app, fingerprintManager.isHardwareDetected() returns false. Why? FingerprintManager fingerprintManager = (FingerprintManager) getSystemService(FINGERPRINT_SERVICE); if(!fingerprintManager.isHardwareDetected()){ textView.setText("Your Device does not have a Fingerprint Sensor"); } I have read some answers on Stack Vverflow that there is a problem with the Note4 fingerprint - it is an old phone and

问题 This question already has answers here : Closed 8 years ago . Possible Duplicate: iso 19794-2 fingerprint format. Hi all, I need to develop a system to match fingerprints. all fingerprints are already converted to ISO 19794-2 format. the input will also be in ISO 19794-2 format. how to check whether the input and the fingerprints in database matches or not. is there any algorithm to implement it? i need an algorithm to compare two fingerprints in ISO 19794-2 format. It would be more helpful

问题 The following function gets file offsets from the rabin_polynomial structure, opens the input_file for md5 fingerprint generation and writes the result to fpfile My problem is it seems to use the same chunk_buffer content some times that it generates similar fingerprints for chunks with different legths. What could be the reason? I have tested the md5 function with other inputs separately and it generates correct digests. int write_rabin_fingerprints_to_binary_file(FILE *fpfile,FILE *input

问题 I was curious if it's posible to integrate a fingerprint scanner to a Flash/Flex/AIR application, I can't seem to find anything on the web. 回答1: I believe currently there's no way to directly connect to external devices using AIR, but if you use something like Merapi (http://www.merapiproject.net/), you could write a java api that would allow you to do a lot more. 来源： https://stackoverflow.com/questions/1500832/is-there-a-way-to-use-a-fingerprint-scanner-with-flex

问题 I am Capturing image from a finger print Scanner and i want to display the captured image live in an Image control. //Onclick of a Button Thread WorkerThread = new Thread(new ThreadStart(CaptureThread)); WorkerThread.Start(); So i created a thread as above and called the method that captures the image from the device and sets the source of the Image control as follows. private void CaptureThread() { m_bScanning = true; while (!m_bCancelOperation) { GetFrame(); if (m_Frame != null) {

问题 I have a requirement where the same iPhone is shared among a small set of people. Is there an iOS API that allows me to determine who unlocked the phone, so that I can create a user-specific display of my application? 回答1: Nope, can't be done. All you know is that the Touch ID succeeded or not. Keep in mind that an iOS device with Touch ID has no concept of a user. You can simply register several different finger prints. None are tied to a specific person. 来源： https://stackoverflow.com

问题 When we call mFingerprintManager .authenticate(cryptoObject, 0 /* flags */, mCancellationSignal, this, null); I notice that it is completely fine to pass null for cryptoObject . According to FingerprintManager documentation FingerprintManager.CryptoObject: object associated with the call or null if none required. According to https://github.com/googlesamples/android-FingerprintDialog, it shows a lengthy step to create CryptoObject . So, I'm not sure, whether I should use a CryptoObject , or

问题 I was working on a fingerprint recognition project. As a part of an orientation field estimation algorithm the input fingerprint image should be divided into blocks and have to compute gradients at each pixel in each block and my question is how this gradients are calculated. 回答1: You need to be more specific about the type of gradient . Gradient can mean one of: Sobel (vertical, horizontal, or combined) Laplacian Approximations/alternatives to the above (e.g. Scharr) From looking at your

问题 When user scanned his finger, i want to learn which finger is printed, middle or second or nth. Is it possible on IOS/CORDOVA or do you have an hack for it? 回答1: While it is possible for a user to label their finger scans that is optional and un-reliable. Other than that I don't believe the software can detect which finger; even pet paws have even registered. Further iOS does not keep the scanned finger print but that information may not help you. 回答2: Yes an no. It is not possible to do this

问题 Hello Android developers, I've got something strange in my app when I'm using the Fingerprint and the AndroidKeystoreProvider together. Here is the case: I create a KeyPair with KeyPairGenerator. In the builder I have set setUserAuthenticationRequired(true) and setUserAuthenticationValidityDurationSeconds(10) . Into my fingerprint I have enrolled 3 fingers. When I try next to init the Signature algorithm with initSign(...) the first time, UserNotAuthenticatedException is catched. That's fair.