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One major problem with your tests is that you're basing them on your own perception. How about measuring the SNR between the original and compressed versions. That way you'll have a numerical comparison instead of saying "because I said so." I have no doubt that HD Photo is better, but you don't have any concrete numbers.

Another thing is that HD Photo's rival should really be JPEG2000, not JPEG. Comparing HD Photo to JPEG is like comparing VC1 or H.264 to MPEG1.

You can make a TIFF of the actual two images side by side after they are compressed so we could see them.

Much better Emil, this is a much better test using much higher quality photos (with much higher bit per pixel original images). This new format has lots of potential, especially considering its going to be free. It looks like you're saving something like 30-40% size at what you think is a not noticeable compression level. If this gets implemented into digital cameras thats a lot more photos per CF or SD card (with the potential to have those "more" photos being of a higher quality and more colourfull).

I'm not sure jpeg2000 is even relevant, regardless of its abilities, it's been out for years now and I have yet to see one image posted anywhere that uses that format... ok except for today when someone posted one in Emil's earlier thread....before that, never. It sounds like this is due to licensing costs, which will no doubt, never change so I'm not sure why it keeps getting brought up.

Thanx for the more indepth and useful comparison Emil.

Frazer

I haven't actually looked at any pictures or read anything about Microsoft's new format but I have some questions about your "test".



Is this a typo or are you trying to make me believe the a jpeg saved at maximum compression doesn't have artifacts?





Here you have the same image with different filesize at WDP@0.5/1. How did that happen?

For those who are familiar with signal processing:

HD Photo Versus JPEG

HD Photo is based on lapped biorthogonal transform (LBT), which in itself is based of discrete cosine transform (DCT), which is based on discrete fourier transform (DFT).

LBT was developed to handle the blocking issue that occurs between borders with a normal DCT.

So if you're comparing JPEG to HD Photo, of course HD Photo is going to look better, but at the cost of performance because of the additional "smoothing" operations.

Also, since LBT is based on DFT, they are both going to distort at approximately the same rate. This means that as you drop the file size the image quality for both HD Photo and JPEG should drop by the same amount.

HD Photo Versus JPEG 2000

JPEG 2000 is based of this new concept called discrete wavelet tranform (DWT).

Fourier Transform basically takes a function and tries to represent it with sines and cosines. The coefficients are the values that are stored, which makes the images smaller.

Wavelets on the other hand try to generalize what the Fourier Transform does by allowing basis functions other then sine and cosine. The basis functions must still average to zero, just like the sine and cosine functions.

Theoretically speaking, wavelets allow for better compactification versus fourier because you can choose the optimal basis function that allows you to represent the signal you're working with.

Here is an paper that shows that JPEG 2000 can be significantly better then HD Photo as you compress the images more. Remember, PSNR is logarithmic, therefore any small change in PSNR dramatically alters the quality of the image.

http://www.compression.ru/video/codec_comp...mparison_en.pdf

Last edited by dduardo on 11 Mar 2007 - 03:44

A side question. Let's take A 1.0MB black and white TIFF image of a crouching man. When I zoom it in to max using default Windows Picture Viewer, I do not see any pixelation, pretty cool. Why is that??? It's not like TIFF is a vector format.

See now this kind of discussion is what makes Neowin awesome.
It's still largely a "this is what i notice" test, but it's still a good indicator.

Good work.

Normal JPEG's can be optimized further (I.E. it is not well optimized by default). This application lets you set different compression levels for color and luminance values, and can increase PERCEIVED quality by quite a bit.

Also, there is a difference between Black and White (1bit), Grayscale (8/16bit) and Color (24/48bit). Grayscale != Black and White.

Hm.....
you can see difference only if you compress picture to the maximum, and who will make that ? If you converting picture you like to be good not to be distorted. When converting from RAW or PSD there is not difference. I take shot with my Canon 400D with RAW quality and compare pictures. There is not BIG differences. It is hard to compare all formats because WDP format can be opened an seen only in Windows Photo Gallery in Vista and Photoshop. PSD format can't be seen in Windows Photo Gallery so you can't compare this formats here. Programs like ACDSee or XnView have support for PSD, JPG, JPEG2000 but not for WDP, so I compare all formats but screenshot is only from WDP 16 bit at Low quality and JPG 8 bit at Low quality saved with Photoshop (0 quality). It's a part of a picture. Test archive with all formats is 35,0 MB I can't post it here.
This is RapidShare link: Compare fileformats

will the new format support transparent stuff?

I've done a comparison between Jpg and Jpeg2000 using the same Tiff files given above, again using the freeware FastStone Image Viewer (btw, XnView is another free program that fully supports Jpeg2000).
I used the same size for the Jp2 files as for the Wdp files in the test above to have a good base for comparison.

I've uploaded Jpg and Jp2 in a zip here so you can compare for yourself:
http://rapidshare.com/files/20515297/Neowi...rison2.zip.html

First part (lowest Jpg quality)
1) Crouching man
With nearly half the size of the Jpg file, Jp2 doesn't have any artifacts, but loses a little bit of sharpness.

2) World map
With hardly any difference in file size, the quality of Jp2 is clearly superior to Jpg (which by itself is superior to Wdp... now there's food for thought).

3) Boxer
Even though the Jp2 file has less than half the size of the Jpg file, it still has clearly better quality.

4) Dave Legg’s laptop
Again, the Jp2 file has a clearly better quality than Jpg, even though the Jp2 is only about half the size.

5) Metal art plate
Even with the lowest quality possible (1%), I couldn't get the Jpg smaller than 377kB. With Jp2, I easily hit 173kB at a quality of 20% (so it could've got quite a bit smaller still). Again, the Jp2 quality beats that of the Jpg.

Second Part (Jpg 50% quality)
1) Crouching man
At 50% quality, the Jpg is 100kB, while the Jp2 is 51kB. Pretty much half the file size for the same quality.

2) World map
Here, the Jpg is 331kB with 50%, while Jp2 is 308kB, but retains a better quality. With a quality of 20%, Jp2 has a comparable quality with a file size of 123kB (well below half).

3) Boxer
Jpg with 50% quality reaches 410kB, while Jp2 is reaching 200kB there (less than half).

4) Dave Legg’s laptop
Using 50% quality, Jpg takes still 2.5MB, while Jp2 takes only 1.4MB while still having better quality. Jp2 reaches a comparable quality at 25% with a file size of 737kB (less than a third).

5) Metal art plate
A full 2.6MB is the space a Jpg with 50% quality still requires here. Jp2 manages quite an amazing feat here as its file at 50% quality is only 411kB, which is only about 16% of the size!

Conclusion:
With greyscale pics, Jp2 generally has half the file size (or even less) of Jpg at the same quality setting.
With colour pics, the quality setting though is not comparable. While Jp2 pics with the same setting (e.g. 50%) are still bigger than half the size, they still have better quality, so you generally can reduce the setting to get a file with half the file size and still have a quality that is comparable to the Jpg file.

In essence, one could say that Jp2 (unlike Wpd) fully fulfills the claim: “It compresses data twice as efficiently as JPEG, with either twice the quality at a given file size or half the file size at a given quality.”

I can't say I'm too impressed by HD Photo yet. JPEG is certainly due for a replacement, but a quick test shows the quality to be worse at the same file size. Perhaps the Photoshop plugin isn't up to the task yet, but the results aren't even as good as JPEG.

Here's an example showing exactly what I mean. To me, the HDP version doesn't look nearly as good:

http://farm1.static.flickr.com/128/4176383...745780e3c_o.png

I've tried it and I may say, JPEG and PNG are better

Well, if you wanted to show us what the difference was, why not just save the original file as a WDP and JPG, then re-save them as PNG images?

haha...its bloody pictures formats..get over it

who cares????
as long as it looks gd and doensnt eat my space..im happy

anyone know where a plugin can be found?

Instead of relying on the 'art' where lines and colours can be lost, why don't you do a test with alphanumeric content?

If a high resolution picture of a letterboard, maybe submitted in raw format from someone who has a camera capable enough is posted ... will that not be a better judge than a few pictures with fine details that getlost and unnoticed?

Why do people keep comparing it to jpeg2000? That format is practically dead thanks to all sorts of legal reasons. I mean ffs, look at the name, it's been around since 2000 and 7 years on, nobody uses it for anything.

Ok, I am so tired of everyone trying to compare HD Photo (Windows Media Photo) and JPG.

Either you don't get it, or you are trying to create controversy that doesn't exist.

HD Photo DOES several things you cannot do univerally in other formats, including JPG. The fact that the image quality is on par with JPeg is just one of the side effects.

Here is what IS important about HD Photo...

• HD Photo does Mipmaps (for example, a website could provide a HIGH RESOLUTION IMAGE in HD Photo format, but only the displayed thumbnail size selected is sent to the client. Examples of this can be found in the British Library applications that are using HD Photo and Microsoft's 3D Photo project that combines photos in high resolution into a semi virtual 3D space.)

• HD Photo provides higher bit storage than JPEG, this gives professional photographers the ability to use the full spectrum of what the new digital imaging chips are producing, even though most people cannot see the difference with the naked eye. And yes the extra bits are VERY important when dealing with image manipulation and output.)

• HD Photo allows for BOTH Lossy and Non-Lossy compression. JPEG is Lossy only, and other formats are usually all non-Lossy. HD Photo gives the best of both world options in one format. (i.e. Non-Lossy great for Text and Graphic Arts, Lossy Great for Photos)

• HD Photo is designed to chunk data specifically in the way digital imaging devices capture the Raw image, this speeds up the process of getting the data from the imager to the storage device on the card, and by also being faster than JPEG extra speed is added even further.

There currently is NO image format standard that meets just these features that HD Photo does in one format. Right now we are having to choose between PNG, TIFF, JPG, etc. And each has advantages and limitations making any form of universal image currently not possible. For example, you could decide to go with PNG for your media, but PNG doesn't support meta tags, or you could go with TIFF, but it is more of an enclosure layer and the compression used inside can be many different types and cause problems with software that don't understand the internal compression, or you could choose JPG, but lose resolution, color fidelity and lossless compression.

Instead, you could use HD Photo which doesn't have the same limitations, and we could eventually move to a universal image format that not only does more than what we need today, but is extensible enough to support even future imaging needs.

All this comparing JPG to HD Photo is crap, as you are using beta software and then trying to determine the quality based on your eye. And if your monitor is more contrasted than someone else’s, one format is going to look better, and if your monitor is less contrasted another format is going to look better. Let alone the fact you are viewing these images on LCDs and Monitors that CANNOT even product the entire spectrum of the format in the first place. If you think you can see the difference between 24bit and 36bit on an LCD that displays at 18bit, you are insane.

So please stop the comparisons..

And I apologize to the person who wrote this article in advanced, but if this is your knowledge and understanding of digital imaging, you need to find someone else to do these types of reviews.