Private Squoosh-derived image codec

MozJPEG Image Compressor

Encode JPG, PNG, or WebP pixels as a progressive, quality-controlled JPEG with the MozJPEG WebAssembly codec.

Free to use Your source image and encoded result stay in temporary browser memory and are never uploaded to Lucaden.

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How it works

Complete the job in three clear steps

Choose one JPG, PNG, or WebP image from this device.
Adjust the available codec settings and create a progressive JPEG with MozJPEG via @jsquash/jpeg 1.6.0.
Compare the dimensions and file sizes, inspect the full result, then download it.

Important

Check the result before relying on it

Keep an untouched copy of important source files. Browser processing depends on available device memory, and you should inspect every downloaded result before deleting the original.

Practical details

What this Lucaden tool does

Encode JPG, PNG, or WebP pixels as a progressive, quality-controlled JPEG with the MozJPEG WebAssembly codec.

JPEG is lossy and cannot store transparency. Lucaden places transparent pixels on the selected solid background, so inspect edges, gradients, and fine text before replacing the source.

Lucaden adds a focused workflow, conservative memory limits, honest size reporting, local previews, and exact dependency attribution.

Included capabilities

MozJPEG encoding
Progressive JPEG output
Quality and trellis controls
Local WebAssembly processing

Useful for

Optimize a website photograph
Prepare a compatible email image
Compress a product photo
Compare browser and MozJPEG output

Questions

About this tool

Does Lucaden upload the image?

No. Browser APIs decode the selected pixels and the pinned jSquash WebAssembly codec runs locally.

What should I verify?

JPEG is lossy and cannot store transparency. Lucaden places transparent pixels on the selected solid background, so inspect edges, gradients, and fine text before replacing the source.

Which open-source engine is used?

MozJPEG via @jsquash/jpeg 1.6.0 is provided through a version-pinned jSquash package derived from the Squoosh codec work. jSquash remains Apache-2.0 and retains its upstream attribution.

Open-source foundations

Built transparently

Lucaden documents its standards sources, architectural references, and permissive runtime dependencies while keeping this workspace consistent with the Lucaden interface.

jSquashApache-2.0 source Third-party noticesLicenses and attribution