Image Upscaler
Enlarges 2× or 4× with a directional interpolator that keeps diagonal edges sharp, with no model to download.
This is an interpolator, not a generative model. Nothing is downloaded, nothing is uploaded, and it will not invent a face that was four pixels wide — what it does is enlarge without staircasing the diagonals, which is the part ordinary bicubic gets wrong.
Drop an image to enlarge
No model is downloaded and nothing is uploaded — see the note below for what actually runs.
How to use it
Say what kind of picture it is
Illustration and screenshot go through DCCI, which continues a 45° edge instead of stair-stepping it. Photograph does not, because DCCI has no measured advantage on grain and claiming otherwise would be the easy thing to do.
Pick the scale
DCCI works in doublings, so 2× and 4× run it alone and 1.5× or 3× run it and then trim with the resampling filter. The panel lists the exact chain before you start.
Check the output megapixels
A 4× enlargement is sixteen times the pixels. Above about 40 megapixels the page warns you, because that is where it becomes several seconds and a lot of memory.
Common questions
Can it recover a face from a blurry CCTV frame?
No, and neither can anything else honestly. Detail that was not photographed can only be invented, and inventing it needs a trained prior — a model. There is no model here.
Why is the sharpen slider greyed out?
Because DCCI ran. The unsharp mask exists to rescue edges a separable filter softened; DCCI already preserved them, and sharpening on top only adds halos.
How is DCCI better than plain bicubic?
It chooses its interpolation axis per pixel from the local gradient instead of always working along the rows and columns. Measured against separable cubic in this repo’s own suite: better on diagonal edges and strokes, within a fifth of a decibel on noisy texture and axis-aligned strokes, where it has no advantage.
Feed it from
Photo Denoiser
Removes sensor grain from high-ISO photos while keeping edges, with a strength slider.
JPEG Artifact Cleaner
Smooths the 8×8 blocking and ringing left by heavy JPEG compression or repeated re-saving.
PNG Compressor
Quantises the palette and rewrites the deflate stream to shrink a PNG without changing its dimensions.
JPEG Compressor
Re-encodes a JPEG at a chosen quality with a live before/after size and a difference view.
Next
These accept what this tool produces, so the result can go straight in.
Photo Denoiser
Removes sensor grain from high-ISO photos while keeping edges, with a strength slider.
Brightness & Colour Adjust
Adjusts brightness, contrast, saturation, temperature and sharpness with a live histogram.
JPEG Artifact Cleaner
Smooths the 8×8 blocking and ringing left by heavy JPEG compression or repeated re-saving.
PNG Compressor
Quantises the palette and rewrites the deflate stream to shrink a PNG without changing its dimensions.
Background Remover
Keys out a flat or single-colour background in OKLab and returns a transparent PNG, with a brush for fixing the edges.
EXIF Remover
Strips camera, GPS and editing metadata from photos while leaving the pixels untouched.