图片相似度计算（直方图、峰值信噪比、结构相似性、感知哈希算法）、轮廓检测、直线检测、圆检测、角点检测、直线交点计算、旋转角度矫正、图像匹配的对应相似处连线、灰度、二值化、直方图均衡化。

Calculate PhotoDNA hashes using Python

CLI Java wrapper for the PhotoDNA library

Perceptual hashing command-line tool

Perceptual Hash in J

audio perceptual hash extraction library

A library of perceptual hash algorithms (aHash, dHash, pHash, wHash).

Universal social-media & video scraper — X/Twitter, YouTube, Vimeo + generic video discovery + impersonation detection via perceptual hashing. Stdlib-only core. No API keys required.

Here will be C++ library for perceptual image hashes.

Android librarry (kotlin) : Image (JPEG, BMP) comparison (perceptual hash algorithm)

Find matching Iconify icons by visual similarity

Generate content-based image hashes on Node.js.

Let's find out duplicate images with Perceptual Hashing algorithms

Batch-rename and deduplicate photos and videos using EXIF/QuickTime metadata, perceptual hashing, and Apple Live Photo pairing.

Lightning-fast Go library and CLI for visual and structural PDF comparison

Python tools for cleaning up large photo libraries - remove duplicates, screenshots, and similar images with a browser-based review UI

从PPT录屏视频中提取不相似帧，从而逆向构建PPT各页

PHP Compare Image (algoritm Average Hash, Simple Hash)

Go library & CLI for computing 64-bit perceptual image hashes (pHash).

Enterprise-grade cloud picture platform based on Spring Boot 4 + Java 21, featuring JWT auth, RBAC, multi-tenant team spaces, content moderation, AI-assisted tagging, real-time collaboration via STOMP/WebSocket, perceptual hash deduplication, and pluggable COS/local storage with two-level Caffeine + Redis cache.