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Std conversion of image file type creates files much much larger

Posted: Sun Aug 07, 2022 4:33 am
by dec
converting JPG to PNG is creating files massively larger eg 1mb > 7mb

Re: Std conversion of image file type creates files much much larger

Posted: Sun Aug 07, 2022 7:12 am
by xnview
It's normal, JPEG is lossy format, and PNG is lossless format

Re: Std conversion of image file type creates files much much larger

Posted: Sun Aug 07, 2022 9:42 am
by dec
this is not my experience with conversions with other graphics programs

Re: Std conversion of image file type creates files much much larger

Posted: Tue Aug 09, 2022 6:54 am
by xnview
could you post the ouput from XnView and from other app?

Re: Std conversion of image file type creates files much much larger

Posted: Tue Aug 09, 2022 1:22 pm
by dec
difficult because i do not want to upload 10mb files

Re: Std conversion of image file type creates files much much larger

Posted: Tue Aug 09, 2022 1:52 pm
by cday
You could possibly post screenshots of the viewer File > Properties... display for a JPEG, and for the same file converted to PNG by XnView MP, and if possible another software that you say produces smaller output sizes...

You might also look at the PNG save compression level set, the default values is 6 and I don't think increasing the value to the maximum of 9 reduces the filesize very much.

I believe without checking that the PNG format supports alternative compression methods, and that the content of the image being saved may also significantly affect the size of the output file, with areas of uniform colour possibly compressing very well.

Re: Std conversion of image file type creates files much much larger

Posted: Tue Aug 09, 2022 3:40 pm
by dec
thank you.
will check some things.