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albytastic

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JPEG or RAW?
« on: February 08, 2019, 09:38:06 am »

With the various arguments about whether Topaz Labs new product "JPEG to RAW" actually can turn a JPEG into a 16 bit TIFF or DNG file.

The usual argument in favour of using RAW is that a JPEG, being only 8 bits, has lost too much digital information for it to become a 16 bit file.

So here is a little test - I have posted 2 images on my Flickr site, can you tell the difference?

A little hint - both were processed in J2R then edited exactly the same way.

They are both 100% crops.

https://www.flickr.com/photos/20926615@N05/46303221754/in/dateposted-public/

https://www.flickr.com/photos/20926615@N05/46303183134/in/dateposted-public/

Look forward to your replies.
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Slobodan Blagojevic

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Re: JPEG or RAW?
« Reply #1 on: February 08, 2019, 10:01:35 am »

... both were processed in J2R then edited exactly the same way.

You started with a raw file and processed it in J2R!?

Mark D Segal

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Re: JPEG or RAW?
« Reply #2 on: February 08, 2019, 10:08:29 am »

I subscribe to Ask Tim Grey's daily newsletter in which he answers readers' questions, and today's email is about Topaz JPEG to RAW. Here is Tim's text:

<<Today's Question
I got an email about software from Topaz Labs that claims to convert JPEG images to raw captures. Is that even possible, and if so will it provide all of the benefits of raw?

Tim's Quick Answer:
The "JPEG to RAW AI" software from Topaz Labs does not provide the same benefits as a raw capture, and frankly I feel that their marketing around this software is misleading.

More Detail:
"JPEG to RAW AI" from Topaz Labs enables you to batch process JPEG images and convert them to a DNG or TIFF image with a 16-bit per channel bit depth. As part of the processing, various enhancements are applied to the image. The claim is that the result will be greater dynamic range, a larger color space, higher bit depth, reduced artifacts, and increased detail.
 
To begin with, converting a JPEG image to a DNG or TIFF file format with a different color space and higher bit-depth setting does not provide any quality benefit for the image all by itself. The only real benefit from these changes would be the potential for better image quality after applying strong adjustments. The exact same results could be achieved by changing the color space and bit depth for an image in Photoshop, for example, with no visible change in appearance for the photo.
 
After testing a variety of images with JPEG to RAW AI, I did not find that there was any significant improvement in the level of detail in the photos. Some photos showed evidence of contrast enhancement and sharpening in certain areas, which obviously could also be applied using other software.
 
While some of the visible artifacts in JPEG images I tested with JPEG to RAW AI were reduced, in areas where artifacts were reduced overall sharpness and detail were also reduced. In some cases detail enhancement in certain areas of an image actually increased the visibility of artifacts in the image.
 
Overall I was not impressed with the results I achieved with the JPEG images I processed with JPEG to RAW AI. More worrisome to me, however, is that I feel the way the product is being marketed is misleading. While I do feel that some of the software products from Topaz Labs are very good, I would not recommend JPEG to RAW AI.
 
If you'd like to check out JPEG to RAW AI for yourself, you can get more info on the Topaz Labs website here:
 
https://topazlabs.com/jpeg-to-raw-ai/ref/273/  >>

It seems that Tim tested the application with at least several sample photos to come to these conclusions.

Beyond what Tim reports, I wonder just how much quality enhancement inventing data can provide. To some extent and depending on the operations being performed, it can be useful; but we need to be mindful that for many of our cameras, bit depth exceeds JPEG bit-depth and the JPEG has already eliminated much of the scene referred raw data that a camera sensor records, so any processing already starts with that disadvantage, which would most likely make a visible difference to image quality the more the photo is processed and magnified. Of course the only way to know for sure whether this application does good things for us is to try it in the context of our own requirements and see. I won't be doing so because none of my photography uses JPEG as the initial capture format. I only record raw files and periodically convert some photos to JPEG as useful for transmission over the Internet.
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Re: JPEG or RAW?
« Reply #3 on: February 08, 2019, 10:18:28 am »


Look forward to your replies.

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albytastic

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Re: JPEG or RAW?
« Reply #4 on: February 08, 2019, 11:41:37 am »

You started with a raw file and processed it in J2R!?

Wrong!
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Slobodan Blagojevic

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Re: JPEG or RAW?
« Reply #5 on: February 08, 2019, 11:46:15 am »

Wrong!

So what exactly are you asking us? Can we tell the difference between what? Your thread title and subsequent explanation implies that one of the two images started as a raw file.

albytastic

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Re: JPEG or RAW?
« Reply #6 on: February 08, 2019, 11:49:03 am »

So what exactly are you asking us? Can we tell the difference between what? Your thread title and subsequent explanation implies that one of the two images started as a raw file.

Wrong again!
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Garnick

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Re: JPEG or RAW?
« Reply #7 on: February 08, 2019, 11:49:55 am »

With the various arguments about whether Topaz Labs new product "JPEG to RAW" actually can turn a JPEG into a 16 bit TIFF or DNG file.

The usual argument in favour of using RAW is that a JPEG, being only 8 bits, has lost too much digital information for it to become a 16 bit file.

So here is a little test - I have posted 2 images on my Flickr site, can you tell the difference?

A little hint - both were processed in J2R then edited exactly the same way.

They are both 100% crops.

https://www.flickr.com/photos/20926615@N05/46303221754/in/dateposted-public/

https://www.flickr.com/photos/20926615@N05/46303183134/in/dateposted-public/

Look forward to your replies.


First of all, your first sentence is irrelevant.  Photoshop can do this as well, has been able to do so for many versions.

The second sentence is also somewhat irrelevant.  A JPEG file has 8 bits per channel.  All of this has been previously explained but I will do so one more time.  If you convert a JPEG file to a 16bit file the container is only half full.  You have therefore accomplished nothing.  As far as I'm aware the only way to convert an 8bit file to a true 16bit file is through interpolation, which is never the best approach.  Since we do not know how you have processed each of your example files that is also an irrelevant exercise in my opinion. 

Andrew has many times asked for some real time proof of the claims made by Topaz concerning J2R.  I agree with Andrew to some extent, that being the fact that the initial promotion of this new Topaz app is very misleading.  So basically they're playing a word game here.  If the product is as good as they claim, why not invent a new word to use in their advertising campaign that does not imply that a JPEG  file can magically become a RAW 16bit file? 

Bart has just put up two examples as well and I will say it is starting to look like something to be investigated further.  I have and use some of the Topaz plugins and for the most part they do what is advertised, and with no hyperbole. 

Now here's a test for you.  Open two new files in Photoshop, one 8bit and one 16bit at a size of approximately 10x3".  Now create a gradient from absolute black to absolute white across the 10' dimension on each file, 8 & 16bit.  Then posterize the gradient on each file with 21 steps, or as many steps as you like.  Now look at each file.  The demarcation between steps should look quite different, rather blurred and dirty in the 8bit file as opposed to the clean demarcation between steps in the 16bit file.  Now here's the tricky part.  Convert the 8bit file to 16bits.  Do the demarcations between the steps look any better now?  And of course the answer is NO.  That's because all you have done is put an 8bit file into a 16bit container.  Nothing more and nothing less.  You have not increased the bit depth of the 8bit file.  Now do the same with the 16bit file, convert it to 8bit.  You will notice no difference in the demarcation between steps because all you have done is put the 16bit file into a smaller 8bit container.  In other words, all of the data in the 16bit file has been squished down to fit the 8bit container.  However, if you now try to make some rather difficult adjustment to that new 8bit file you will see problems, because you have discarded some of the actual bit depth you had in the 16bit file and you can never get it back again. 

Perhaps at some point AI will indeed be able to do a much higher quality interpolation routine.  And as I mentioned, Bart's examples are very interesting and I may try the demo as well, but I will not jump on board for full $$ commitment until there's more proof of absolute quality.

Gary
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Slobodan Blagojevic

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Re: JPEG or RAW?
« Reply #8 on: February 08, 2019, 11:57:40 am »

Wrong again!

WTH!? Cat got your tongue!? Can't you answer a simple question?

albytastic

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Re: JPEG or RAW?
« Reply #9 on: February 08, 2019, 12:09:17 pm »


First of all, your first sentence is irrelevant.  Photoshop can do this as well, has been able to do so for many versions.

The second sentence is also somewhat irrelevant.  A JPEG file has 8 bits per channel.  All of this has been previously explained but I will do so one more time.  If you convert a JPEG file to a 16bit file the container is only half full.  You have therefore accomplished nothing.  As far as I'm aware the only way to convert an 8bit file to a true 16bit file is through interpolation, which is never the best approach.  Since we do not know how you have processed each of your example files that is also an irrelevant exercise in my opinion. 

Andrew has many times asked for some real time proof of the claims made by Topaz concerning J2R.  I agree with Andrew to some extent, that being the fact that the initial promotion of this new Topaz app is very misleading.  So basically they're playing a word game here.  If the product is as good as they claim, why not invent a new word to use in their advertising campaign that does not imply that a JPEG  file can magically become a RAW 16bit file? 

Bart has just put up two examples as well and I will say it is starting to look like something to be investigated further.  I have and use some of the Topaz plugins and for the most part they do what is advertised, and with no hyperbole. 

Now here's a test for you.  Open two new files in Photoshop, one 8bit and one 16bit at a size of approximately 10x3".  Now create a gradient from absolute black to absolute white across the 10' dimension on each file, 8 & 16bit.  Then posterize the gradient on each file with 21 steps, or as many steps as you like.  Now look at each file.  The demarcation between steps should look quite different, rather blurred and dirty in the 8bit file as opposed to the clean demarcation between steps in the 16bit file.  Now here's the tricky part.  Convert the 8bit file to 16bits.  Do the demarcations between the steps look any better now?  And of course the answer is NO.  That's because all you have done is put an 8bit file into a 16bit container.  Nothing more and nothing less.  You have not increased the bit depth of the 8bit file.  Now do the same with the 16bit file, convert it to 8bit.  You will notice no difference in the demarcation between steps because all you have done is put the 16bit file into a smaller 8bit container.  In other words, all of the data in the 16bit file has been squished down to fit the 8bit container.  However, if you now try to make some rather difficult adjustment to that new 8bit file you will see problems, because you have discarded some of the actual bit depth you had in the 16bit file and you can never get it back again. 

Perhaps at some point AI will indeed be able to do a much higher quality interpolation routine.  And as I mentioned, Bart's examples are very interesting and I may try the demo as well, but I will not jump on board for full $$ commitment until there's more proof of absolute quality.

Gary

An interesting idea and I will try it when I have time.

But the actual purpose of the 2 test images was simple - how much infomation is there in a JPEG that could be used by JPEG to RAW?

And the answer is a lot more than most people realise.

They were both JPEGs from my Canon 1Ds MkII which gives 16 MP images.

Test A is the original JPEG, just over 10MB in size.

Test B is a reduced version of that - 833Kb in fact!

The original JPEG was reduced by Easy Thumbnails and kept the image size but reduced the filesize (JPEG Quality set to 60%)

Yet it still produced a good image despite the huge loss of data.

So if it is possible to produce a good image from such a small filesize it means there is a huge amount of available data in JPEGs.

So I see no reason why Topaz Program cannot use this data to do exactly what it says.

Both full size images remained at 16MP regardless of the filesize.
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digitaldog

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Re: JPEG or RAW?
« Reply #10 on: February 08, 2019, 12:50:21 pm »

With the various arguments about whether Topaz Labs new product "JPEG to RAW" actually can turn a JPEG into a 16 bit TIFF or DNG file.
What arguments? There's nothing at all unique or special about converting a JPEG to a TIFF into DNG and upping the bit depth. Been doable for couple of decades.
What's bogus is the idea Topaz Labs converts a JPEG to raw data.
Converting a JPEG to DNG absolutely doesn't make it raw! You were told this fact in the other post: DNG like TIFF is simply a container. A JPEG converted to DNG is a JPEG in the DNG wrapper. You can open a JPEG in Photoshop, change the mode to 16-bit and make a DNG. It's still not raw. You didn't add any additional data, you simply provided a finer encoding of the existing numbers!
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albytastic

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Re: JPEG or RAW?
« Reply #11 on: February 08, 2019, 12:53:56 pm »

What arguments? There's nothing at all unique or special about converting a JPEG to a TIFF into DNG and upping the bit depth. Been doable for couple of decades.
What's bogus is the idea Topaz Labs converts a JPEG to raw data.
Converting a JPEG to DNG absolutely doesn't make it raw! You were told this fact in the other post: DNG like TIFF is simply a container. A JPEG converted to DNG is a JPEG in the DNG wrapper. You can open a JPEG in Photoshop, change the mode to 16-bit and make a DNG. It's still not raw. You didn't add any additional data, you simply provided a finer encoding of the existing numbers!

Not what I was actually getting at.
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Re: JPEG or RAW?
« Reply #12 on: February 08, 2019, 12:58:26 pm »

Not what I was actually getting at.
What are you trying to get at? Use your words. Here are some of your words which are not correct (there's no such argument):
The usual argument in favour of using RAW is that a JPEG, being only 8 bits, has lost too much digital information for it to become a 16 bit file.
Got very little to do with bit depth and a lot to do with the difference between a raw, un-rendered piece of digital clay and a JPEG which is baked by something else you have no control over (compared to raw). The extra bit depth is simply icing on the cake. I'll post this again here for you to examine facts about the differences in raw plus JPEG (and there's more but this is a lot):

The JPEG engine that processes the raw massively clips and compresses highlights. We often don't when editing the raw. This compression can clump midtones as much as 1 stop while compressing shadow details! People incorrectly state that raw has more highlight data but the fact is, the DR captured is an attribute of the capture system; it's all there in the raw but maybe not in a camera proceed JPEG.
A raw capture that's 10 or 11 stops of dynamic range can be compressed to 7 stops from this JPEG processing which is a significant amount of data and tonal loss! So when we hear people state that a raw has more DR than a JPEG, it's due to the poor rendering or handling of the data to create that JPEG. The rendering of this data and the reduction of dynamic range is from the JPEG engine that isn't handling the DR data that does exists as well as we can from the raw! Another reason to capture and render the raw data, assuming you care about how the image is rendered!

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Mark D Segal

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Re: JPEG or RAW?
« Reply #13 on: February 08, 2019, 01:07:32 pm »

What arguments? There's nothing at all unique or special about converting a JPEG to a TIFF into DNG and upping the bit depth. Been doable for couple of decades.
What's bogus is the idea Topaz Labs converts a JPEG to raw data.
Converting a JPEG to DNG absolutely doesn't make it raw! You were told this fact in the other post: DNG like TIFF is simply a container. A JPEG converted to DNG is a JPEG in the DNG wrapper. You can open a JPEG in Photoshop, change the mode to 16-bit and make a DNG. It's still not raw. You didn't add any additional data, you simply provided a finer encoding of the existing numbers!

Exactly, and what I was getting at in Reply #2 though in a different way. By the time an image becomes a JPEG it is encoded as pixels and cannot be raw. The only raw data is what the camera captures at the time of capture. Taking your thought a bit further, this is not the first time the same error has been made, with certain developers claiming that the files their software produces are raw when all they've done is to encase fully rendered, pixel-based data in a DNG container.

Now, turning to the 8 to 16-bit part of it, Andrew, you say this is providing a finer encoding of the existing numbers. In a way, yes, the encoding may be finer because 8 depth becomes 16 depth, but is the real content of it any finer? Information is being invented to do this. Is it safe to say that invented information is in one way or another largely a clone of existing information, and therefore doesn't contribute anything incrementally useful to how the file can be edited or purposed?
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Re: JPEG or RAW?
« Reply #14 on: February 08, 2019, 01:16:28 pm »

Exactly, and what I was getting at in Reply #2 though in a different way. By the time an image becomes a JPEG it is encoded as pixels and cannot be raw. The only raw data is what the camera captures at the time of capture. Taking your thought a bit further, this is not the first time the same error has been made, with certain developers claiming that the files their software produces are raw when all they've done is to encase fully rendered, pixel-based data in a DNG container.
I think both are points are falling on deaf ears that need a lot more education on this topic.

Quote
Now, turning to the 8 to 16-bit part of it, Andrew, you say this is providing a finer encoding of the existing numbers. In a way, yes, the encoding may be finer because 8 depth becomes 16 depth, but is the real content of it any finer? Information is being invented to do this. Is it safe to say that invented information is in one way or another largely a clone of existing information, and therefore doesn't contribute anything incrementally useful to how the file can be edited or purposed?
It's quite possible subsequent editing now on high bit data could be useful but there are too many factors to declare one way or the other: what kind of edit, what condition was the JPEG in, in the first place.
As you know, LR and ACR process JPEGs in high bit, wide gamut. That's how their processing engines operate. There are advantages to parametric editing and at least in terms of Adobe, that the edits are applied in a fixed order, not user order. So there are possible difference in just the order edits are applied (Photoshop vs. LR) that alone could factor into this. Too many variables.
What people need to understand, most certainly the OP, is there's no free lunch. Raw, high bit, wide gamut potential (let alone huge options for rendering) isn't anything like a baked, sRGB JPEG in 8-bits per color.
A carrot cake isn't the same as the individual ingredients used to make that cake and you can't extract them and start over again. Raw equates to the ingredients and how you deal with those ingredients plays a massive role in the outcome. JPEG is the baked cake. You can add more icing perhaps or sprinkles. But if you used salt instead of sugar to make that cake, NOTHING will make it taste right. No matter how much additional sugar you pour on top of it.
These facts are ignored by some who are looking for magic software with algorithm's that contain unicorns, coded by the tooth fairy. Those that think one can use a product to convert a JPEG into raw data. We can't get them out of that unreality bubble easily.  :-[
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Re: JPEG or RAW?
« Reply #15 on: February 08, 2019, 01:27:54 pm »

Exactly, and what I was getting at in Reply #2 though in a different way. By the time an image becomes a JPEG it is encoded as pixels and cannot be raw. The only raw data is what the camera captures at the time of capture. Taking your thought a bit further, this is not the first time the same error has been made, with certain developers claiming that the files their software produces are raw when all they've done is to encase fully rendered, pixel-based data in a DNG container.

Hi Mark,

Quite true, if that were all that happens here.

With all the risk of failure that's inherent with analogies, maybe the following concept is of some use to those unfamiliar with A.I.:
The challenge is not unlike trying to unscramble an omelet.

It is not possible with traditional means, but we can try by starting over with fresh image fragments eggs and through a process of training and learning (scrambling and comparing the new result with the omelet we had), one might be able to approach the result of the omelet at hand, and maybe improve it in certain aspects. If improved, we achieved that by using (newly synthesized) Raw files eggs.

Cheers,
Bart
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Re: JPEG or RAW?
« Reply #16 on: February 08, 2019, 01:41:10 pm »

Hi Bart,

OK, Andrew posted at 1:16 and you posted at 1:27 so presumably you saw what he wrote. Does this boil down to the proposition that only the tooth fairy can unscramble omelettes, or does A.I. really make it possible to reverse-engineer or parse what is an already heavily compromised data base into anything resembling what the original raw data would have been like? I have to say that regardless of the amazing things A.I. can do these days, I remain thoroughly unconvinced about this one.
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Re: JPEG or RAW?
« Reply #17 on: February 08, 2019, 01:46:10 pm »

Does this boil down to the proposition that only the tooth fairy can unscramble omelettes, or does A.I. really make it possible to reverse-engineer or parse what is an already heavily compromised data base into anything resembling what the original raw data would have been like? I have to say that regardless of the amazing things A.I. can do these days, I remain thoroughly unconvinced about this one.
Content aware fill frequently works surprisingly well.
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Mark D Segal

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Re: JPEG or RAW?
« Reply #18 on: February 08, 2019, 01:55:33 pm »

Content aware fill frequently works surprisingly well.

Correct, and that's why near the bottom of Reply 2 I said invented information can be useful.
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Re: JPEG or RAW?
« Reply #19 on: February 08, 2019, 01:58:33 pm »

Hi Mark,

Quite true, if that were all that happens here.

With all the risk of failure that's inherent with analogies, maybe the following concept is of some use to those unfamiliar with A.I.:
The challenge is not unlike trying to unscramble an omelet.
The challenge is telling the truth with a software manufacturer that tells us that's what it's doing; converting a JPEG into raw.
They don't have to say that, since it's untrue. But they have decided to go that route. I find it inexcusable. But some don't mind being lied to.
A.I. isn't converting the JPEG to raw.
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