How Do I Zip A Jpeg File --------

  Clive of India 22:46 24 Jan 2017
Locked

Hi Guys

Can anyone tell me if I’m doing something wrong, I need to compress a photo which I’ve saved to my computer in the form of a jpeg.

I’ve right clicked the jpeg image and then clicked Send to Compressed (zipped) folder. When I click properties on the zipped file, the file size is still the same size.

What am I doing wrong, incidentally I’m using Windows 10 with Microsoft Office Professional 2016 if that has anything to do with it.

Thanks for any advice

Clive

  lotvic 22:52 24 Jan 2017

Why don't some files compress very much? info read kb.winzip.com click here

  alanrwood 11:15 25 Jan 2017

A jpg is already compressed so not much room for any additional compression.

  Forum Editor 12:10 25 Jan 2017

Additional compression of a jpeg is going to result in loss of image quality, and I'm wondering why you need to do it?

  Burn-it 13:44 25 Jan 2017

Just Zipping a jpeg should NOT change the quality since zip is a lossless compression. However, as pointed out, there is little point sinces JPEG is already compressed and a zip of it is likely to be larger than the original since extra zip headers are added.

It is also worth pointing out here that openning a JPEG in an editor and resaving it WILL cause a loss of detail (unless you take care NOT to let the save re-compress it) since JPEG is a LOSSY compression.

Browsing should not affect it unless you (by some method) force a resave.

  Clive of India 17:50 25 Jan 2017

Hi Guys

First off thank you all for taking the time to reply, and for the link you gave me lotvic, at least I now know why I couldn’t compress the files any further.

I guess I could try a couple of things, trim the image size or re take the photos at a lower camera setting at the moment the camera is set at 14M for printing A2 (16” x 20”).

I’m just as bad with cameras as I am with computers, the camera is capable of taking photos at 14M, 10M, 7M, 5M, 3M and 0.3M I’m not sure which would be the best for uploading to the internet, guess I will just have to experiment.

Forum Editor, the reason I wanted to compress the photos was in order to upload them onto a website and the maximum size they will accept is 5MB, so I at least need to get them below that size.

  lotvic 17:58 25 Jan 2017

If you are going to alter photos like that, I advise you copy them and work with the copy, that way you will always have the original to go back to (and make another copy of) if you mess up.

  Clive of India 18:40 25 Jan 2017

lotvic

Point taken, mind you in this instance it wouldn’t be a great loss if I messed up they aren’t very thrilling photos anyway, well unless you think pictures of the underside of the car are anything to get excited about :)

  Burn-it 00:05 26 Jan 2017

The point of working with copies is that if someone comes back to you and asks you to show a section of the picture a bit larger, you still have the original which has not been chopped and resaved to go back to without having to take the pictures again. I always take pictures in as high a resolution as I can afford the space to save and always save the original as a bitmap or other NON-LOSSY format so I can always start again with any adjustments. Often colour correction is needed as well as cropping.

  Bris 15:14 26 Jan 2017

This link may help click here.

As Burn-it suggested its essential to work on a copy of the original because you cant recover the detail lost when you change then save the JPEG.

  lotvic 18:01 26 Jan 2017

A quick way to get a small file of a pic or a close-up of a section of a pic:

  1. Open the pic in whatever pic viewing program you have.
  2. Zoom in (hold down Ctrl and scroll the mouse wheel then use bottom and side scroll to centre on screen the part of the pic you want.
  3. Hold down Alt and press PrintScreen on keyboard (takes a screenshot of the open window)
  4. Open Paint or similar program and paste the screenshot in.
  5. Edit as required.
  6. Save the pic and it will be less than 1MB

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