---
name: "jpegqs"
section: "1"
platform: "linux"
package: "jpegqs"
version: "1.20210408-3"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/jpegqs"
---

# jpegqs(1)

JPEG artifacts removal

## NAME

**JPEG Quant Smooth** - JPEG artifacts removal

## DESCRIPTION

This program tries to recover the lost precision of DCT coefficients based on a quantization table from a JPEG image. The result is saved as a JPEG image with quantization set to 1 (like a JPEG saved at 100% quality).

## SYNOPSIS

**jpegqs**\[*options*\] *input.jpg* *output.jpg*

## OPTIONS

- **-q, --quality n**

  Quality setting (0-6, default is 3)/home/rainbow/Desktop/pngtest/jpegrestore/jpegqs.1

- **-n, --niter n**

  Number of iterations (default is 3)

-

  \* More iterations can make the result look like CG art, can make the photos look unnatural.

- **-t, --threads n**

  Set the number of CPU threads to use

- **-o, --optimize**

  Option for libjpeg to produce smaller output file

- **-v, --verbose n**

  Print libjpeg debug output

- **-i, --info n**

  Print quantsmooth debug output (default is 15).

  Use the sum of flags:

  0 - silent

  1/2/4 - various information

  8 - processing time

  16 - SIMD type

  \* The processing time includes only the smoothing algorithm, jpeg reading and writing time is not included.

- **-p, --cpu n**

  Use to lower the SIMD type if CPU detection fails:

  0 - auto

  1 - scalar

  2 - SSE2

  3 - AVX2

  4 - AVX512

  \* x86 build selects between modes 1-3, x86\_64 from 2-4

## QUALITY

- The quality setting sets a combination of flags for processing:

  - 3\. default

  - 4\. adds DIAGONALS flag

  smoother diagonal edges, ~1.5 times slower

- 5\. adds JOINT\_YUV flag

  chroma channels will depend from luminance, better color consistency

- 6\. adds UPSAMPLE\_UV flag

  non-blurring chroma upsampling, unlike fancy upsampling from libjpeg

- levels 0-2 is the same as 4-6, but with LOW\_QUALITY flag

  \~10 times faster, but the quality is lower

  LOW\_QUALITY implies DIAGONALS (always set)

## PROJECT PAGE

- https://github.com/ilyakurdyukov/jpeg-quantsmooth

  ## COPYRIGHT

- Copyright (C) 2016-2021 Ilya Kurdyukov