How do I compress a jpg file?

[walter_strong2]

I'd like to compress some of my jpg files to 150 kb for posting on

another website. How does one go about doing this? I have PS 6 and

Photo Deluxe.

[noshir_patel]

In PS6, use the "save for web" command from the "file" menu. In the resulting dialog, adjust the quality until it tells you a file size close to what you want (I think it displays this under the image). It also provides a preview so you can see how much image degradation you are going to get.

[Jerry_]

.jpg files are pretty much compressed. You can size your image smaller, resulting in few K. A 700x400 pixel image is somewhat large in file size, where a 300x200 pixel image is much smaller.

 

A large image .jpg file is not going to compress much.

[swenson]

In PS 5 as well as others you 'save as' even if you are replacing.

This forces the same quality dialog box. The lower the quality the

more the compression.

[jlewis]

Walter,

 

I think there are two things to worry about: (1) the display size of your image and (2) the file size. Worry about #1 first, using image, resize to get the image the size you want it on the viewer's screen (1 " equal 72 pixels.) Save this as a TIFF file under a new name. (Every time you open and resave a JPEG file, you lose detail due to JPEG compression, so use it only as the last step.)

 

Now open Save For Web, reassign the file type as JPEG in the righthand box, and follow the instructions the others have given you. My guess is that your image may come in well under the 150 kb you specified, but if not, you can reduce the quality using the sliders until you get the file size you need (it displays at the bottom on the work area.)

 

Jim Lewis

[ahaohio]

Always work with a copy of your original file!!

 

The compression in JPG files is "lossy" which means that if you compress the file information in the original file is actually lost - forever unless you have the original file someplace.

[Former P.N Member]

Before worrying about the file size you need to address the issue of image quality. I've put together a demonstration of the image degradation inherent with JPG compression and posted it at <a href="http://casualphotos.vze.com/Web-JPGCompress">http://casualphotos.vze.com/Web-JPGCompress</a>. (A word of warning, some of the images are over 250k so loading may take a while.)

<p>

The advice you got as to how to do it is correct after you determine how much you want to do.

<p>

Dick

[gordonr]

This kind of question has been asked before, and covered in the archives. Try reading <a href="http://www.photo.net/bboard/q-and-a-fetch-msg.tcl?msg_id=000jrw">Ideal compression rate for JPEG Format</a> (http://www.photo.net/bboard/q-and-a-fetch-msg.tcl?msg_id=000jrw) and other related threads.

[steve_hovland]

150kb is a bit big for a web photo.

 

Due to common modem speeds, 50 kb is a better size.

 

On my site, the "big" pictures are 4" by 4" at 100 dpi.

[paul_purcell]

When you Save (or Save As) a JPG, there is a JPG Quality Scale somewhere on that save screen. Change the JPG quality number to a lesser quality number (which may be up or down the scale; depends on the particular program--it should tell you right there at the scale which way is which) to make a JPG compress more. Up to a certain point, there is little visible difference for having a smaller file size, but experiment to see what works for you because image definition and quality can suffer if you go too far.

[dave_mcmicken]

<p>This doesn't solve your problem if you're posting pictures on a website for viewing but it will if you're posting them as zip files on sites like rapidshare to share with others.<br /> <br /> I use Shrink to compress all my pictures. I compressed 366mb of pictures to one 125mb file. On a single picture, I was able to reduce the picture size by 82%. The big thing is that Shrink does it with no loss of image quality. I know everyone says you can't compress jpgs but Shrink does it and the images maintain the same dimensions, memory size and image quality of the originals when decompressed.<br /> <br /> I was skeptical but compared original pictures with decompressed ones and found no difference even after zooming the view in.<br /> <br /> It also makes sending email faster. I got my brother to use it so our emails wouldn't take forever to send when we attached pictures.<br /> <br /> Shrink is really cheap to register and you can it here-<br /> http://www.sharewaregenie.com/ShrinkReview.php<br /> <br /> I hope this helped.<br /> <br /></p>