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Sinding Large Image files - what is the best metho

What is the best method for sending large image files - i.e above 1mb?

Would it be better for the sender to upload the images to a free online photo album service and the recipient to download from the online phto service?

Or to zip the image files and send each image by separate emails?

Not Paul Gaugain
Monday, August 25, 2003

Also, How would you move Mt. Fuji?

In other words, Not Enough Info.

GiorgioG
Monday, August 25, 2003

Unless you're dealing w/ large uncompressed files, you won't get much mileage from zipping (jpeg compression does a good job).

I've done it a variety of ways.  Usually clients had an FTP server I just uploaded to.  Others I've e-mailed.  I guess you could burn to a CD, but that would be a pain after a while.

Lee
Monday, August 25, 2003

Aw, that idiotic question about mount Fuji again...

John
Monday, August 25, 2003

"Unless you're dealing w/ large uncompressed files, you won't get much mileage from zipping (jpeg compression does a good job)."

That's very much dependent on what sort of jpegs you're dealing with.

Jpeg has variable compression so you can compress a little (and still have excellent quality) or compress a lot (with reduction in image quality).  If you're dealing with low quality jpegs that are optimized for use on web pages, then, yes, you won't get much of a benefit from zipping.  But you'll still get some.

But if you're dealing with large high-quality jpegs (like of photographs), then you'll get a huge benefit from zipping them before transfer.  You'd be silly not to do it.

Herbert Sitz
Monday, August 25, 2003

Lee -- Sorry about that last comment of mine; unfortunately it's not a rare thing for me to put my foot in my mouth.

But I was a little surprised to find out I was dead wrong.

I did some testing, and it turns out that jpegs of all quality levels are indeed compressed about as much as they can be without losing quality.  High-quality jpegs may be big, but it seems you can't compress them much lower with a lossless compression scheme.  You can apply some lossy compression by converting them into a lower quality jpeg.  But again, the lower quality jpeg won't benefit much at all from applying a lossless compression scheme to it.

Herbert Sitz
Monday, August 25, 2003

<quote>
High-quality jpegs may be big, but it seems you can't compress them much lower with a lossless compression scheme. 
</quote>

If you think about it, that is fairly obvious. I mean, if there was an easy way to compress a high quality JPEG using lossless compression - then surely JPEG would use that algorithm rather than its lossy one!

Seeua

Matthew
Monday, August 25, 2003

If you are very particular of the image quality then use PNG compression which is loseless. But JPEG compressed images are also very good in quality.

cooler
Tuesday, August 26, 2003

The basic rule of thumb I find works for reducing image sizes:

If you have images which have gradients (photos would be a good example), you can save a lot of space by using JPEG without sacrificing quality noticeably

If you have images which must be very precise and pixel-perfect, with definite edges, then PNG works wonders.

Now if they just get the alpha channel for PNG working in IE, I'll be happy...

Konrad
Tuesday, August 26, 2003

Just to state the most obvious solutions:

1. Reduce the color depth.
2. Reduce the dimensions.
3. Configure an FTP or Web server at the source*.
4. Configure an FTP server at the destination.
5. Burn a CD and ship it.

* If you have a cable modem Internet connection, it's likely you already have space reserved for a Web site.

If you have an alternative full-time Internet connection, you can configure an FTP server in Windows relatively easily using IIS, although thoroughly reading the documentation for instructions on how to make it secure is a very good idea.

Dave
Tuesday, August 26, 2003

If there aren't any firewalls in the way, you can both use the same Instant Messenging program, be online at the same time and upload the file directly.

I'd be interested in hearing any other ideas that don't involve external storage space, are limited to email account size or require changing the firewall settings. I.e. something my dad can use to send his home movie to other family members.

Big B
Tuesday, August 26, 2003

The best way to send large image files is not to send them at all. More seriously, it's to provide the recipient with thumbnails and let them choose if they want to go ahead and download the larger version (this is actually a cool thing that some of the "wavelet" image compression programs did: As you enlarged your copy, it would download the delta to add the enhanced information -- i.e. what you previously downloaded wasn't all wasted).

Dennis Forbes
Tuesday, August 26, 2003

Herbert Sitz:

Yeah, the only way you can compress furthur is if the format is in a TIFF or something raw. JPEG applies a loss-less compression on whatever quality it has decided on. So you can think of it as two pass:

Phase 1. Lossy compression, what you decide to key or give up.  Without the help of Phase 2 this is compressible.

Phase 2. Compression.

But it's not really two pass.. so I am confusing everyone and myself here.

Li-fan Chen
Tuesday, August 26, 2003

Hi

I found a great software for compression Images. It is simply amazing though it has a strange name Miliki Super Compressor. It compresses even JPEG files over 10 times better than any Zip program and the quality is great.

You can download a 30 day free trial on Download.com
http://download.com.com/3150-2250-0.html?tag=dir

Ihope this helps!:))

Tony Ola
Thursday, September 04, 2003

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