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Compressing pics without loosing visible quality


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dear members

I use paint.net to edit, resize, and compress my digital camera jpeg photos.

Normally I resize my photos (by: image-->resize) to 550*411 pixels, and compress them to less then 40K (save as-->filename.jpeg -->quality setting) in order to publish them on the internet.

with my old camera, after cutting the unnecessary edges, and resizing, I could get under the limit of 40k with a quality of about 90% which practically shows no difference from the original quality.

Now I have a new camera with many more pixels (even when I use it in its lowest pixel mode: 3.5M), and in order to get the same results (image size and file size) I have to choose a quality of about 55%, and that visibly damages the photo.

So, with my new camera, respecting the limit of 40k, I end up with a poorer result then with my old camera.

Is there any manipulation I can do in order to avoid this problem ?

Thanks in advance

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Hello Crimson and Survulus

I thank you for your quick answers.

I've tried you use your advices but I couldn't see amelioration of quality.

I use to add small text to the photo, and the text looks really bad.

I uploaded an example original photo and the resulting photos on

http://bonnielovesclyde.free.fr/

The quality option is not proportional to the file size. The file size decrease rapidly when going down to 70% quality, but lower then that, the file size is practically “stucked” thogh I continue decreasing the quality.

I reached 40k at a poor quality of 16%.

I think (haven’t tried it yet) to photograph my objects from a bigger distance in order to have more background to cut out, in order to start with less pixels in the first place

Regards

Amir

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I tried a couple of things on your photo and I could keep the quality at about 90.

The biggest problem in your example is the part of the background you didn't remove, with a completly white background it was easier. The filesize depends on the image size (number of pixels used), and the number of colors (and transparancy in .png, .gif etc.).

40Kb image:

Untitled.jpg

(bad grammar in the image, sorry...)

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Hello somesone93

thanks for your answer, the photo you've attached respond well to my needs:

pic size 550*365 pixels, file size less then 40k, and good quality.

unfortunately I could not produce the same result.

also after cleaning totaly the background.

(you can see also my new try on http://bonnielovesclyde.free.fr )

can you please give me more details about the operations you've executed and their order.

thanks in advance

Amir

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Select pretty close to the object (try to make the selection the same ratio as you want it to be in the end)

Crop canvas to the selection.

Use the magic wand to remove the most of the background, then remove the rest with the eraser or whatever you like.

New layer, fill with white and move that layer down.

(By now, before the resizing, I can get the size to 40Kb at quality 37)

Resize and crop it to the right size if you need it.

New layer, write text.

Save, filetype jpeg, and put the quality so the size is correct.

Hope this will help! :wink:

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Hello someone93, thanks again for your kind help.

It drives me crazy, I’ve passed hours on this, I tried to follow exactly your steps, or use other methods for cropping or for cleaning the background, but I always end up with a picture of about 125k (even without text in the pic) which needs to loose quality until 17% in order to reach 40k.

Maybe there are some definitions to change in paint.net

(I use paint.net v3.36)

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That's wierd...

If I whould've saved the image before I resized it in the last steps the imagesize whould be about that high.

Edit: I don't get this, I took the result from your site (copy, pasted it) and tried to save. 93 quality needed.

Then I used save image as, then opened and saved. 17 quality needed.

It's the exactly the same image... :?

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yes, I've tried the same actions (copy/paist vs. save as) and the results are different.

stange things are happening in the kingdom of paint.net...

never had compression problems with images from my old camera (though original image and file size are similier.

I maybe try to repost my question in a more precise way.

otherwize, maybe someone can recommand me a good image compression software ?

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well I just addopted the Idea of someone93 who mentioned that by copy/paste he had no problem achiving 40k in about 90% quality.

So I open the "problematic" photo in paint.net I copy/paste it into a new paint.net file and the problem is gone.

see for yourself, I reattach a sample photo here. (to experience the problem you should save it instead of copy/past it)

3873_9cd1058f1c7531f41c1c34de8affacad

and as for my new camera (sony DSLR a350) I'm still learning it, as it has too many options. but I don't think I'm using any infrared stuff.... :oops:

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The infra-red have some noise, And it doesn't look good in the daylight (if you have/had it on). And by scaling down the size it would/could help (on the camera) If this alternatives doesn't help you, then give it back to Sony ;)

Nah, am just joking. Every camera has it own settings, Just for you to get used to ;)

U2l6xrt.png

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