JPEG , JPEG 2000 and JPEG Stereo

[bnnrcn]

When I save my PSD files as JPEGs in PS CC , I always choose JPEG (JPG, JPEG, JPE) option. But there are also JPEG 2000 (JPF,JPX, JP2, J2C, J2K,JPC) and JPEG Stereo (JPS) options. I don't know what they are used for and because there are so many options I don't know if my choice (JPEG) is the best one

I would be happy to hear your opinions about it

[John 2]

.................confused:......

....and so am I even after reading this explanation on Wiki

http://en.wikipedia.org/wiki/JPEG_2000

However, although JPG 2000 is supposed to improve on the original, I'm guessing the real controlling factor is what the forum software will handle. I suspect that JPG 2000 may not be compatible. Try it and see.

Jpg stereo seems to be just the standard JPG format but in double the width to allow stereo pairs to sit alongside each other(?).

[bnnrcn]

Thank you John. It says in the link you posted that JPEG 2000 is not widely supported in web browsers hence is not generally used on the internet. So , it is better to stick with the old JPEG format

I googled jpg stereo format and found this http://www.stereomerger.com/mw/index.php/Stereo_JPEG

....and so am I even after reading this explanation on Wiki

http://en.wikipedia.org/wiki/JPEG_2000

However, although JPG 2000 is supposed to improve on the original, I'm guessing the real controlling factor is what the forum software will handle. I suspect that JPG 2000 may not be compatible. Try it and see.

Jpg stereo seems to be just the standard JPG format but in double the width to allow stereo pairs to sit alongside each other(?).

[Geoff F]

For everything except internet and a few exports on disc to various users, I keep with PSD which creates smaller files than Tiff but without any quality loss. In theory, PSD should remain an available format for evermore, unlike some software native formats which could be unusable when that company goes out of business.

But, yes, many programmes which require images from me won't accept anything except regular Jpeg. I accidentally gave some photos on a CD to a commercial printer (for use in a printed programme) and left them as Tiff. He couldn't open the files so he took it to several other people, including a web designer and nobody could access the photos!

And technology has now advanced so far that his composing computer won't even accept discs! I have to put images on a memory stick for him.

Anyway, returning to the original question; I have tried Jpeg 2000 which is supposed to be lossless compression but found it took so much time to create files that it wasn't really worthwhile. Even longer than creating a Tiff.

Then, as previously mentioned, only a few other users could open these files.

Jpeg isn't the only format which exists in a number of odd forms. There are also a considerable number of Tiff versions.

PNG is another potentially useful format which isn't so widely supported now.

[dje]

Hi Binnur

I can only go on what I've read such as the Wiki article but jpeg2000 appears to be a new improved standard that simply didn't provide sufficient benefit to warrant it's universal acceptance, given it was introduced 14 years ago !

Stereo jpeg appears to be a specialised format for 3D imaging. It brings back memories for me of my early career in microwave radio system design when we used stereo photos (prints of course) and an optical stereo viewer to get a 3D view of the topology of the land along a microwave path !

Dave

[tclune]

I can only go on what I've read such as the Wiki article but jpeg2000 appears to be a new improved standard that simply didn't provide sufficient benefit to warrant it's universal acceptance, given it was introduced 14 years ago !

Before I retired, I worked a lot with imaging compression in medical applications. The main thing that slowed down acceptance of Jpeg2000 was the legal situation -- the underlying wavelet technology was patented, and there was considerable concern that use of the format could expose businesses that used it to lawsuits and possible monetary damages. The JPEG group tried to get assurances that this would not happen, but the nature of the assurances was always murky.

The attractive things about JPEG2000 over the original JPEG standard included that you could compress further without visible artifacts (the Wikipedia article downplays this, but we found that typically you could cut the file sizes in half from those of the older DCT-based technology for the same quality output); that lossless JPEG2000 was just a choice of compression level instead of a different algorithm; that you could specify a desired file size and achieve it without having to iterate on the compression (DCT compression varies with the image, and so cannot be set in advance: wavelets can); and, for general use, the artifacts that JPEG2000 introduces when an image is compressed too much are considerably less objectionable than the artifacts in over-compressed JPEGs. The last point is interesting because one of the major attractions of the original JPEG compression to medical imaging is that the artifacts are so unnatural that they are readily recognizable as artifacts of compression. Wavelet compression, on the other hand, looks quite natural. In some medical contexts, the compression artifact can be confused with a clinical condition -- which might lead to an unnecessary biopsy, for example. But, with your vacation photos, a bit of unobtrusive "ricing" created by the compression algorithm is much to be preferred to random squares scattered over your lovely landscape shot. So, for general use, JPEG2000 has genuine advantages on a technology level. But, at this point, the biggest problem in internet use is the general lack of support for the format on websites. FWIW

[dje]

Tom thanks for that background information, it is most interesting.

Dave

[bnnrcn]

Thank you Geoff, Dave and Tom for the further explanations

Very interesting background info Tom .

[IzzieK]

Geoff when my husband have a hard time trying to send images this friends, he cut and paste his images (?) it as a PDF file and everyone can see it, just pretty much like a word processor I suppose.. because even a MAC has PDF. And oh, I must add, hubby is not graphic nor photo savvy. It is just easier for him to do that.

[Stagecoach]

I have often wondered what JPG 2000 was and now I know about it, thanks Tom.

[Geoff F]

Yes, Izzie, I use PDF a lot. Particularly useful when sending (internet upload or burnt to a disc) and there is a mix of images plus text. So many formats which are used by operations like desktop publishing software etc will not be visible with other software!

When scanning old material, like old programmes or guide books, for my local history society and there is a mix of text, adverts and photos I often find that scanning directly to PDF creates better results than Tiff or Jpeg which eventually needs to be converted to PDF anyway. Obviously, printed photos have to be separately scanned with a descreening photo setting.

Sometimes I scan with OCR software and create new text but a lot of this sort of stuff requires an exact digital copy.

But I have been surprised how many people, who are operating with older systems, still can't accept any PDF.

[mikelilin]

Yes, Izzie, I use PDF a lot. Particularly useful when sending (internet upload or burnt to a disc) and there is a mix of images plus text. So many formats which are used by operations like desktop publishing software etc will not be visible with other software!

When scanning old material, like old programmes or guide books, for my local history society and there is a mix of text, adverts and photos I often find that scanning directly to PDF creates better results than Tiff or Jpeg which eventually needs to be converted to PDF anyway. Obviously, printed photos have to be separately scanned with a descreening photo setting.

Sometimes I scan with free ocr software and create new text but a lot of this sort of stuff requires an exact digital copy.

But I have been surprised how many people, who are operating with older systems, still can't accept any PDF.

I agree, maybe some years later, PDF will replace the image.

[Shadowman]

Geoff when my husband have a hard time trying to send images this friends, he cut and paste his images (?) it as a PDF file and everyone can see it, just pretty much like a word processor I suppose.. because even a MAC has PDF. And oh, I must add, hubby is not graphic nor photo savvy. It is just easier for him to do that.

I couldn't immediately find the original program I used, but this attached link has a program that allows you to print large images and it's saved as a pdf. Usually, when images are imbedded in pdf's the quality isn't that great unless you have additional formatting capabilities. However, programs such as the one in the link produce pretty good enlargements.

http://rasterbator.net/

[Geoff F]

My software which produces PDF does have options for setting different image quality so that is worth adjusting when the data is intended to high quality printing work; although, of course, it does produce larger file sizes.