Overview
Introduction
This tool adds random grain/noise to a JPG entirely client-side using a seeded pseudo-random generator.
It's a quick way to add a film-like texture or a deliberately gritty, textured look to an otherwise clean digital photo.
What Is Noisy JPG Creator?
A client-side JPG noise-generation tool that reads an uploaded photo's pixel data and adds a random offset, scaled by an adjustable intensity, independently to each pixel's red, green, and blue channels.
The randomness comes from a seeded mulberry32 pseudo-random number generator rather than plain `Math.random()`, so the exact same grain pattern can be reproduced later by reusing the same seed.
How Noisy JPG Creator Works
The intensity slider (0-100) scales to a maximum per-channel deviation; for every pixel, each of its red, green, and blue values gets nudged up or down by a random amount within that range, clamped back into the valid 0-255 byte range.
Because the same seed always produces the same sequence of pseudo-random values, running the tool again with an unchanged seed and intensity yields byte-for-byte identical noise placement.
When To Use Noisy JPG Creator
Use it to add a deliberate film-grain aesthetic to a clean digital photo, create a gritty or vintage-feeling background texture, or generate a reproducible noisy test image for evaluating denoising tools.
It's also useful for adding visual texture to an otherwise flat, low-detail solid-color area.
Often used alongside JPG to Glitch Art Converter, JPG Artifacts Adder and PNG Noise Adder.
Features
Advantages
- Runs entirely client-side; nothing is uploaded to a server.
- Seeded, reproducible randomness rather than a different result every time.
- Adjustable intensity spanning subtle grain to heavy static-like noise.
Limitations
- Adds noise uniformly across the whole image; it has no concept of selective/regional grain.
- Heavy noise combined with JPEG's lossy compression can interact in unpredictable ways, sometimes making the output file larger than expected.
Examples
Best Practices & Notes
Best Practices
- Start with a low intensity (5-15) for a natural film-grain feel; save higher values for intentionally gritty or glitchy effects.
- Reuse the same seed when comparing different intensities so only the noise amount changes, not its placement.
Developer Notes
addNoiseToJpg uses the same mulberry32 seeded PRNG pattern as the PNG category's noise adder, scaling intensity (0-100) to a maximum per-channel deviation and applying an independent random delta per RGB channel via clampByte.
Noisy JPG Creator Use Cases
- Adding a deliberate film-grain aesthetic to a clean photo
- Creating a gritty, textured background image
- Generating a reproducible noisy test image for denoising experiments
Common Mistakes
- Expecting a different random pattern each time when the seed hasn't changed: the noise is deterministic per seed by design.
- Using very high intensity and being surprised the JPEG file size grows, since noise is harder for JPEG's compression to model efficiently.
Tips
- Click 'randomize seed' if you want a fresh grain pattern rather than the same one every time.
- Combine with a slight brightness or contrast tweak afterward if the added noise makes the image look slightly duller overall.