Fast hash function with collision possibility near SHA-1

I'm using SHA-1 to detect duplicates in a program handling files. It is not required to be cryptographic strong and may be reversible. I found this list of fast hash functions...

xxHash convert resulting in hash too long

I'm using xxHash for C# to hash a value for consistency. ComputeHash returns a byte[], but I need to store the results in a long. I'm able to convert the results into an int32 using the...

Fastest sort algorithm for millions of UINT64 RGBZ graphics pixels

I am sorting 10+ million uint64_ts with RGB data from .RAW files and 79% of my C program time is spent in qsort. I am looking for a faster sort for this specific data type. Being RAW graphical...

How to shorten a 64-bit hash value down to a 48-bit value?

I already have a 64 bit hash function in a library (C coding), but I only need 48 bits. I need to trim down the 64 bit hash value to a 48 bit value, yet it has to be in a safe manner in order to...

XXHash for PHP (without module/extension)

For on online service, I'm currently using XXHash. Now I'm trying to create a plugin for webshops but these shops are all using PHP, mostly on shared hosting platforms. Problem with this is that...

Numpy reduce multiple operations for hashing

I'm trying to implement some hashing functions for numpy arrays to easily find these inside a big list of arrays, but almost every hashing function I find needs to make a reduce with more than one...

What is the fastest checksumming algorithm for a buffer of size 4096?

I'm looking for a hash/checksum algorithm that is as fast as possible while still being able to detect changes to a 4096 byte memory page. Because the size is fixed I hope it should be possible to...

VS15 throws error C2975 with constexpr and a string literal

I'm trying to implement a class that performs string hashing at compile-time if a literal string is given or else, run-time (based on this article). I'm not using FNV-1a like the author did but...

recommender systems: Convert UUIDs to 32 bit ints for recommender libraries

LightFM and other libraries ask for a 32 bit integer id e.g for users. But, our user id is a UUID e.g. 0003374a-a35c-46ed-96d2-0ea32b753199. I was wondering what you would recommend in scenarios...

Proper way to hash a reader in Rust?

I was attempting to use twox-hash to generate a hash for a file, as it seemed to be the fastest hash implementation around and security is not a concern for this implementation. To get it to work...

Implement non-cryptographic hash functions in C

I was trying to implement hash table in C to store English words. So I was searching through the internet to some of the best non-cryptographic hash functions. Some of them are Murmurhash,...

How well do Non-cryptographic hashes detect errors in data vs. CRC-32 etc.?

Non-cryptographic hashes such as MurmurHash3 and xxHash are almost exclusively designed for hash tables, but they appear to function comparably (and even favorably) to CRC-32, Adler-32 and...

Confused about xxHash

I'm using xxHash to create hashes from elements id. I just don't want to show real id on website. I created script to test is there option to get same hashes: const _ = require('lodash'); const...

Istio 0.8. Details about LoadBalancerSettings.ConsistentHashLB

Could someone provide more details or examples about how works this load balance...

Compiling Dolphin emulator beta

Moved from here, because it's about compiling software. My original problem: I want to play Super Mario Galaxy 2 with another player. But whatever keys I assign to move the cursor, it instead...

Can a big-endian xxhash be compared with a little-endian hash?

I have a set of files that were hashed as xxhash64 (little endian) and stored in an .mhl file. The same set of files were hashed by a separate program, as xxhash64be (big endian) and stored in a...

Why android application gives compiler error for Admob integration using Firebase using c++ SDK

I want to integrate AdMob in cocos2dx 3.17 c++. I have referred https://firebase.google.com/docs/admob/cpp/cocos2d-x link. But I am getting error : Error while executing process...

Memory management in storing Image buffer with hash in screen sharing program

Edit: I am not getting enough response for this question may be i am not able to explain properly. Let i try to explain background to this question. Every screen sharing program there are two...

LKM crashs depends on hardware?

My LKM hijacks stdin/sshd inputs: https://pastebin.com/RChpbt9G # uname -a Linux kali 4.19.0-kali4-amd64 #1 SMP Debian 4.19.28-2kali1 (2019-03-18) x86_64 GNU/Linux I'm using latest kali2019.2 on...

understand the performance diff of std::optional on different platforms

I was trying to understand the overhead of using std::optional in the interface design, whether it's worthing using std::optional for single interface or using combination of "isNull and getX",...

Include C/C++ source files as plugins in IL2CPP

I've been trying to write simple functions in C and use IL2CPP to include them in my plugin directory directly without building DLLs because I find it more straightforward as well as less costly...

Error "Could NOT find PythonLibs" when building Root

I got this message when I tried to install the Root software onto Ubuntu Linux. Please give me advice. What is the problem and how can I manage this? -- The C compiler identification is GNU...

conda update InvalidSpecError

I am trying to update a conda environment: conda update --all but get the following Fetching package metadata ............. InvalidSpecError: Invalid spec: =20190808 output of conda list is as...

XXHash as a Mysql User Defined Function

We store representations of millions of chemical compounds as BLOBs in a MySQL database. We also keep hashes of these BLOBs when we need to query among these compounds and comparing these hashes...

How to full (with all features - ACL support / Xattr support / xxhash library/ zstd library) install (compiling) rsync v3.2.3 on Mac?

I am trying to install rsync 3.2.3 on Mac by compiling it. But, I would like to install with all features. For that, it needs some libraries which in here...

NumPy - fastest non-cryptographic collision-resistant hash

I'm looking for the best 64-bit (or at least 32-bit) hash function for NumPy that has next properties: It is vectorized for numpy, meaning that it should have functions for hashing all elements...

Error "Package ... is not in GOROOT " when "go run"

Firstly, I want to say thank u for reading my topic. I am newbie in Golang so nice to receive your help. I am using golang for php-fpm-exporter (https://github.com/hipages/php-fpm_exporter) My...

Getting error "CUDA backend requires cuDNN" when configuring OpenCV cmake build with cuda backend turned on

My goal: My goal is to configure a build of OpenCV 4.5.1-dev with support for cuda, tesseract and QT without any cmake error.. The problem I am having: I am getting the following error when I...

go.sum are different when using go mod vendor/download

I have a problem with the usage of commands go mod vendor and go mod download in a go module. When I'm using go mod vendor, the generated go.sum has extra-lines. E.g, when I'm using go mod...

Warning: Ignoring XDG_SESSION_TYPE=wayland on Gnome. Use QT_QPA_PLATFORM=wayland to run on Wayland anyway

I try to use library cv2 for changing picture. In mode debug I found out that problem in function cv2.namedWindow: def run(self): name_of_window = 'Test_version' image_cv2 =...