Noise Reduction
Remove noise and grain from photos with advanced denoise algorithms powered by OpenCV. Fix high ISO noise, color noise, and film grain while preserving image details.
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Remove noise and grain from photos with advanced denoise algorithms powered by OpenCV. Fix high ISO noise, color noise, and film grain while preserving image details.
or drop image here or paste
Loading OpenCV.js...
Best for luminance noise. Finds similar patches to average. Preserves edges well.
Image noise reduction removes unwanted grain, speckles, and color artifacts from digital photos using OpenCV's professional-grade algorithms. Noise typically appears in images shot at high ISO settings, in low light conditions, or from older camera sensors. This tool uses industry-standard Non-Local Means denoising and bilateral filtering to intelligently reduce noise while preserving important image details like edges, textures, and fine features.
Upload your noisy image and select an algorithm. Non-Local Means (NLM) is recommended for most photos - it searches for similar patches throughout the image and averages them, effectively removing random noise while keeping real details. Adjust Filter Strength (h parameter) to control noise removal intensity - higher values remove more noise but may blur details. Template Window Size affects the patch size used for comparison. Search Window Size determines how far the algorithm looks for similar patches.
Non-Local Means (fastNlMeansDenoising) is the gold standard for grayscale/luminance noise - it produces excellent results by finding and averaging similar image patches. Non-Local Means Colored (fastNlMeansDenoisingColored) extends this to color images with separate handling of luminance and chrominance. Bilateral Filter smooths while preserving edges using both spatial and intensity differences. Median Filter excels at removing salt-and-pepper noise. Gaussian Filter provides basic smoothing.
Use Non-Local Means for high ISO photos, scanned images, and general noise reduction - it's the best all-around choice. Use NLM Colored when color noise (chroma noise) is prominent - common in digital cameras at high ISO. Bilateral Filter works well for moderate noise when you need speed. Median Filter is ideal for images with speckle noise or salt-and-pepper artifacts. Gaussian Filter should only be used for very light smoothing as it will blur details.
This tool uses OpenCV.js, the JavaScript port of the industry-standard OpenCV library used by professional photographers and image processing applications. The Non-Local Means algorithm implemented here is the same algorithm used in Adobe Lightroom and other professional software. Process images up to 4096x4096 pixels with full resolution output. All processing happens locally in your browser - images never upload to external servers, ensuring complete privacy.