# OpenCV 46 Hacker News commenters recommended OpenCV and 16 criticized it, November 2025 to November 2026. It was recommended in 11 of 13 months. It meets the Hacker Approved badge rule. **Verdict:** Free, long-lived computer vision library that people find easy to start with and fast for image loading. Critics note uneven code and doubt the new engine. ## Why people recommend it - Easy setup and Python bindings (4 comments): "was the biggest boon for my online teaching experience because remotely dealing with install woes" ([source](https://news.ycombinator.com/item?id=48482933)) "was so easy and smooth to set up for doing tasks like generating thumbnails" ([source](https://news.ycombinator.com/item?id=48467772)) "python is easy and the bindings are not that hard" ([source](https://news.ycombinator.com/item?id=48467022)) - Good for learning computer vision (3 comments): "it was OpenCV that made concepts like convolutions, softmax, minmax, and others finally click for me" ([source](https://news.ycombinator.com/item?id=48458388)) "I'm using it to do computer vision stuff (where I have no prior background!) with opencv.js" ([source](https://news.ycombinator.com/item?id=46152481)) "blown away by this announcement and super excited to get back into image processing" ([source](https://news.ycombinator.com/item?id=48472166)) - Fast at loading images and video (3 comments): "it remains hands down the best library for simply loading images and video" ([source](https://news.ycombinator.com/item?id=48459111)) "OpenCV is fast, but torchvision is faster." ([source](https://news.ycombinator.com/item?id=48487801)) "always found opencv to work way way faster" ([source](https://news.ycombinator.com/item?id=45822642)) - Long-lived and widely used underneath (3 comments): "opencv has stood the test of time and I'm certain newer LLMs will likely not attempt to rewrite it from scratch" ([source](https://news.ycombinator.com/item?id=48472001)) "OpenCV is used behind the scenes for many of the fancy stuff those major AI provider pretend to do." ([source](https://news.ycombinator.com/item?id=48459542)) "Despite its age, I think that OpenCV is still more than relevant today." ([source](https://news.ycombinator.com/item?id=48463541)) ## What people warn about - New engine and ONNX questioned (2 comments): "Quite a good release although not sure why they invest so much time into their ONNX engine." ([source](https://news.ycombinator.com/item?id=48459512)) "No one uses ONNXRuntime (nor the new engine in OpenCV 5) in production." ([source](https://news.ycombinator.com/item?id=48458162)) - Uneven code, unstable direction (2 comments): "its constituent parts are written by many different people who all kind of do things a little differently and it shows" ([source](https://news.ycombinator.com/item?id=48462311)) "Perpetual-Beta culture means the library will unlikely ever really fully stabilize." ([source](https://news.ycombinator.com/item?id=48461885)) - Input and gamma handling limits (2 comments): "it will load images with the wrong gamma, it will give you floating point values that hide the limitation" ([source](https://news.ycombinator.com/item?id=48463303)) "The most annoying component is that OpenCV is limited to input shapes like (H, W, C)" ([source](https://news.ycombinator.com/item?id=48487777)) - Slower than rewrites or newer methods (2 comments): "performance is generally pretty low; I've been on projects where we rewrote OpenCV code into more-or-less obvious hand-rolled code and won 5x perf" ([source](https://news.ycombinator.com/item?id=48463020)) "never felt it was particularly complicated, but since the days of resnet there are much faster ways to the goal" ([source](https://news.ycombinator.com/item?id=49337553)) ## Alternatives hackers recommend - [PyTorch](https://hackerapproved.com/p/pytorch.md): 131 recommend - [MLX](https://hackerapproved.com/p/mlx.md): 75 recommend - [JAX](https://hackerapproved.com/p/jax.md): 49 recommend - [tinygrad](https://hackerapproved.com/p/tinygrad.md): 40 recommend - [TensorFlow](https://hackerapproved.com/p/tensorflow.md): 20 recommend ## Cite as Hacker Approved, "OpenCV", https://hackerapproved.com/p/opencv/ (counts from 1,795,640 Hacker News comments, November 2025 to November 2026).