Windows Paint Q ?

Morrisseeee

I have my original image in RAW format (10MB file).
I then save to .JPG (3MB file).
I then open the image in Paint and save as JPG again but now the file is 500KB, same attributes, ie. 3648*2736, 300dpi, bit dept 24 !!
Both JPEGs look very similar and I can't see a quality reduction, even printed as A3's in Black-n-White (ordinary printer paper, 1200*1200 256 shades of gray).
I'm presuming Paint is doing another compression of the file ?

Ricky91t

I'm sure adobe do "camera raw" converter for free someone will give you more info on that

Morrisseeee

No, converting from RAW isn't a problem, I have adobe and Olympus Master, but I was just wondering WHY Paint does another conversion to the JPEG file ? and if you are loosing quality ?

davmigil

Morrisseeee wrote: »

I have my original image in RAW format (10MB file).
I then save to .JPG (3MB file).
I then open the image in Paint and save as JPG again but now the file is 500KB, same attributes, ie. 3648*2736, 300dpi, bit dept 24 !!
Both JPEGs look very similar and I can't see a quality reduction, even printed as A3's in Black-n-White (ordinary printer paper, 1200*1200 256 shades of gray).
I'm presuming Paint is doing another compression of the file ?

Lossy compression. Depending on the initial image difference in quality will be more or less apparent. Try experimenting with different images to see the difference. Also look closely in areas like sky and see if the gradation between light and dark areas is less gradual in the smaller file.

Morrisseeee

Thanks. Will do.;)

sineadw

Every time you save a jpeg from a jpeg it compresses more. That's why you should always go back to the original file when re-working an image..

Morrisseeee

Every time you save a jpeg from a jpeg it compresses more.

Nope, just tried it in Paint. It still is 500KB. Seems like Paint compresses the original JPEG to the max, I know my camera has options to store/save JPEG's in certain compressions (1/4, 1/16 etc), Paint must be using the highest available.

City-Exile

Yeah, MS Paint produces small images.
If you had a full colour bitmap & converted it to jpeg, you'd see a massive degradation!

ThOnda

Some "better" programs will allow you to set level of the file compression and also the file size. It is preset in MS Paint, therefore you have no control about it.
I would suggest using Picture Manager that is in the Windows as well - it offers a little more control.

Morrisseeee

Ah this is the answer I was looking for,

It is preset in MS Paint

, but at what level I wonder !!

Anyways, my Q was just an observation more than anything else.

Quote from the internet (somewhere) : "Microsoft Paint is a minimal (and aged) bitmap editing program. When you save a BMP as JPG, it does not provide you an option to select the compression level from "lowest" quality to "best" quality. I suspect the compression level is fairly low because the produced JPG is very "noisy" (the reconstructed pixels are interpolated incorrectly because too much original information has been removed). For evidence, just draw a short black line at an angle on a white background, save that picture as JPG, then visually inspect the saved JPG: there are now a lot of small dots around the line that used to be clean.

However, it all depends on what you want to use the JPGs for. Better-quality JPGs mean larger files that occupy more disk space and take longer to transfer over the Internet."

democrates

Can your version of MS Paint save as PNG for printing instead of JPG, and if so can MS paint avoid lossy compression that way? There's always bmp of course.

Failing that you could download GIMP, which gives lots of options for jpeg exports. I'm as yet unsure whether setting all options for best quality results in lossless jpg, so again png might be better, or gimps native xcf for total preservation of your post-processing settings.