JPEG to WEBP transcoding quality read JPEG non XL/XR/2K

[Xn User]

Hi )
I have ACDSee Pro 8 with IDE_ACDstd.apl version 5.7.757.0000 with date 2001-2007 years ACDSee Pro 8.2.287 32 bit )
I have XnView MP 1.8.3.0 64 bit version , now I do convert from JPEG to BMP and from BMP to WEBP Lossless in XnConvert Version 1.102.0 - windows x64 (Nov 7 2024) - Libformat version 7.196 files from BMP to WEBP lossless and I get the size of the folder in bytes 1 245 265 152 byte , if do trancoding same files but if do convert from JPEG to BMP in ACDSee Pro 8.2.287 32 bit with IDE_ACDstd.apl version 5.7.757.0000 so result folder size 1 191 895 410 bytes , why ? Where quality more higher ? In XnConvert and XnView MP with transcoding from JPEG to WEBP or in ACDSee Pro with IDE_ACDstd.apl version 5.7.757.0000 and transcoding from BMP to WEBP in XnConvert ? What is the reason for the size of the size? Digital Noise in JPEG decoder from XnSoft or less quality in ACDSee Pro convertation ?

I also spent the test ACDSee Pro 10.4.624 with IDE_ACDstd.apl version 5.9.999.0001 I do transcoding same files from JPEG to BMP in ACDSee Pro and next transcode from result BMP to WEBP with preset Photo method 5 file strenth 100 and filter sharpness 7 , all also as previously and folder size after transcode in XnConvert 1 194 332 160 bytes , e.g. coincided ) why in XnSoftware and Viewer and Converter folder size bigger ?

I'm do test old ACDSee PowerPack 5.0 convert from JPEG to BMP in ACDSee PowerPack 5.0 and next do transcoding from BMP to WEBP in XnConvert 1.102.0 folder size 1 245 265 152 bytes

I'm do testing XnView Classic 2.42 convert from JPEG to BMP in XnView Classic 2.42 and next do transcoding from BMP to WEBP in XnConvert 1.102.0 folder size1 245 265 152 bytes

Total :
ACDSee Pro 8.2.287 folder size after transcode in XnConvert 1.102.0 - 1 191 895 410 bytes
ACDSee Pro 10.4.624 folder size after transcode in XnConvert 1.102.0 - 1 194 332 160 bytes
ACDSee PowerPack 5.0 folder size after transcode in XnConvert 1.102.0 - 1 245 265 152 bytes
XnConvert transcode from JPEG to WEBP folder size - 1 245 265 152 byte
XnViewMP 1.8.3 transcode from JPEG to WEBP folder size - 1 245 265 152 bytes
XnView Classic 2.42 folder size after transcode in XnConvert 1.102.0 - 1 245 265 152 bytes
Why is such a difference in folder size?
Why such result in ACDSee Pro 8 /10 folder smaller ?

I'm test on PSNR and differences 50.47

PSNR ACDSee Pro 6/8/10 vs XnView MP / XnConvert = 50.47
PSNR ACDSee Pro 6/8/10 vs ACDSee PowerPack 5.0 = 50.47
PSNR ACDSee PowerPack 5.0 vs XnView MP / XnConvert = infinity
PSNR XnView Classic vs XnView MP / XnConvert = infinity
PSNR IrfanView vs XnView MP / XnConvert = infinity
PSNR FastStone Image Viewer vs XnView MP / XnConvert = infinity
PSNR Zoner 13 vs XnView Classic / XnView MP / XnConvert = 60.16
PSNR GIMP 2.10.38 vs XnView Classic / XnView MP / XnConvert = 60.12

If I compare result save from JPEG to BMP with original JPEG - result some

Question closed
I understanded what is happening...
If compare with original JPEG file results save from JPEG to BMP and next test

If compare with original :

ACDSee PowerPack 5.0 with original - coincide
XnView Classic 2.52 with original - coincide
XnView MP 1.83 with original - coincide
XnConvert 1.102.0 with original - coincide
Irfanview 4.70 with original - coincide
FastStone Image Viewer 7.9 with original - coincide

But If compare with original

ACDSee Pro 6.3.221 with original - NOT coincide
ACDSee Pro 8.2.287 with original - NOT coincide
ACDSee Pro 10.4.624 with original - NOT coincide
Zoner 13 with original - NOT coincide
Gimp 2.10.38 with original - NOT coincide

I also compare save from Irfanview and original and now In horror , what I considered the standard in fact work so bad.
First I thinked what I be scold the author , but It turned out what I advertised of quality XnSoftware )

[Xn User]

And yet I'm do quality test in ACDSee Pro and XnView MP )
In archive files :

Giant_planes_comparison.svg - original picture
svg_to_bmp.bmp - this is transcoding from SVG to BMP in XnView MP
bmp_to_jpg.jpg - this is transcoding from BMP to JPG in XnView MP with maximum quality for JPEG plugin all set on maximum quality
from-jpeg-to-bmp-xn.bmp - this is backward transcoding from JPEG to BMP in XnView MP
from-jpeg-to-bmp-acd.bmp - this is backward transcoding from JPEG to BMP in ACDSee Pro 8

Mirror in a separate topic viewtopic.php?f=79&t=48281&p=202832#p202832 now when I understand why so , think what need discuss in other topic )

[xnview]

why ? Where quality more higher ? In XnConvert and XnView MP with transcoding from JPEG to WEBP or in ACDSee Pro with IDE_ACDstd.apl version 5.7.757.0000 and transcoding from BMP to WEBP in XnConvert ? What is the reason for the size of the size? Digital Noise in JPEG decoder from XnSoft or less quality in ACDSee Pro convertation ?

I don't know which jpeg decoder & webp encoder is used in ACD

[Xn User]

Talking about only decode from JPEG to any other format , I do so :
Decoding from JPEG to BMP and next compress from BMP to WEBP in your XnConvert 1.102.0 , so result diffirence and depends of PSNR , the more rude it is decoded with very noticeable distortions , those larger file will be in result )
I can sent to you as ACDSee and photo for learn if you want )