DOKK / manpages / debian 12 / jpegqs / jpegqs.1.en
jpegqs(1) General Commands Manual jpegqs(1)

JPEG Quant Smooth - JPEG artifacts removal

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).

jpegqs [options] input.jpg output.jpg

Quality setting (0-6, default is 3)/home/rainbow/Desktop/pngtest/jpegrestore/jpegqs.1
Number of iterations (default is 3)
* More iterations can make the result look like CG art, can make the photos look unnatural.
Set the number of CPU threads to use
Option for libjpeg to produce smaller output file
Print libjpeg debug output
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.

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

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

~10 times faster, but the quality is lower

LOW_QUALITY implies DIAGONALS (always set)

08 Apr 2021 JPEG Quant Smooth