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How does lossless compression in Fuji RAF files work? (2020)

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Re: How does lossless compression in Fuji RAF files work? (2020)

#21

Post by agloe_dreams »

vjvjvjvjghv wrote: post #2

There are always these crazy discussions in photo forums where people are arguing that uncompressed RAW files are better than lossless compressed.

Honestly the best argument for uncompressed is actually nothing to do with file quality or loss - it's that Apple only supports uncompressed Fuji RAWs.

You cannot preview or process lossless compressed Fuji RAWs on iOS natively but the uncompressed files are equal to Apple's own RAWs in support. On the field, it is sadly worth every byte to be able to grab a file directly off the camera and tweak it or send it to an editor. :/

Re: How does lossless compression in Fuji RAF files work? (2020)

#22

Post by ImPleadThe5th »

yboulkaid wrote: post #16

I wonder if something about this explains why Fuji RAF files are the only RAW files that make Lightroom struggle. I never heard the fans on my M1 mac until I started processing those RAF files, they're not even that large but something about them makes Lightroom struggle. And judging by posts on photography forums, I'm not the only one either

I moved away from Adobe recently and ended up trying out Affinity Photo. Opening a RAF file would regularly seize my entire computer.

I always wondered if it was a deadlock situation, because it doesn't spit out any overflow errors.

Re: How does lossless compression in Fuji RAF files work? (2020)

#23

Post by vjvjvjvjghv »

gappa wrote: post #8
matja wrote: post #4

Earlier quoted context omitted.

Those discussions I feel are fuelled by manufacturers like Sony saying [0] things like: Lossless compressed RAW: ... This is a popular format that occupies less space with minimal quality loss. "minimal" "loss"? That's not "no loss", so what exactly is it? [0] https://www.sony.co.uk/electronics/support/articles/00257081

I actually asked Sony Support about that. Their reply: "We can confirm that with Lossless compressed RAW there is a minimal quality loss. To have no impact on image quality I suggest using Uncompressed RAW files." Lossless isn't what it used to be.

That's insane. I honestly thought that lossless basically means to run zip over the file and not more.

Gotta hate companies these days with their dishonesty. "Lossless" means "lossy". "Unlimited" means "limited to 50GB".

Re: How does lossless compression in Fuji RAF files work? (2020)

#24

Post by vjvjvjvjghv »

agloe_dreams wrote: post #21
vjvjvjvjghv wrote: post #2

There are always these crazy discussions in photo forums where people are arguing that uncompressed RAW files are better than lossless compressed.

Honestly the best argument for uncompressed is actually nothing to do with file quality or loss - it's that Apple only supports uncompressed Fuji RAWs. You cannot preview or process lossless compressed Fuji RAWs on iOS natively but the uncompressed files are equal to Apple's own RAWs in support. On the field, it is sadly worth every byte to be able to grab a file directly off the camera and tweak it or send it to an…

The problem is that the size difference between compressed and uncompressed is enormous. This adds up quickly if you shoot sports or wildlife with 20fps bursts.

Re: How does lossless compression in Fuji RAF files work? (2020)

#25

Post by guillego »

Analemma_ wrote: post #15
vadansky wrote: post #12

Earlier quoted context omitted.

I've been thinking of buying that camera for a while, do you recommend it? Do you have anything to say that will finally push me over the edge to actually but it?

I recently upgraded from an XT-3 to an XT-5, but loved my XT-3 and would still recommend it as a good purchase if you can find a decent deal on one in good condition. Fuji’s AF is not the best in the business, so I wouldn’t recommend one if you’re planning on using it for e.g. sports photography, but apart from that the XT series has no real downsides. The physical dials for ISO+exposure+shutter speed are fantastic a…

I have an XT-1 from 2015 (still working!) and recently started considering upgrading to an XT-5 but I'm a little hesitant to buy a "new" camera first released in 2023 that still retails for almost the same price as two years ago. I'm so torn between just going for it and waiting (who knows how long) for the X-T6 to come out. Perhaps I should just try to find a good deal on an X-T4.

Re: How does lossless compression in Fuji RAF files work? (2020)

#26

Post by jcynix »

mlyle wrote: post #10
jsheard wrote: post #3

Earlier quoted context omitted.

Glad to hear that audiophiles have some competition in who can invent the most pointless things to split hairs over. The photo guys need to start taping magic rocks to their cameras to really keep up though.

The problem is camera marketing makes it really unclear what you're actually getting. Really lossless? Does it trigger more on-body processing? Does it throw away bits to be "visually lossless"? If you shoot a few thousand photos and then find you can't fix exposure as well as you'd hoped and the whole batch is worse, it's a pretty big disappointment, so it's smart to be risk adverse and skeptical.

>The problem is camera marketing [...]

IMHO marketing is almost always (part of) the problem. They shouldn't drink or smoke that stuff …

Equating "lossless" with "visually lossless" or some other phrase is newspeak. We could call a JPEG of quality >= 95 (or 96 .. 99) visually lossless too then.

Losslessness is easy to define: compress something, then uncompress it again and both the original and the uncompressed file should compute to the same (cryptographic) checksum.

Re: How does lossless compression in Fuji RAF files work? (2020)

#27

Post by adgjlsfhk1 »

miladyincontrol wrote: post #9
jsheard wrote: post #3

Earlier quoted context omitted.

Glad to hear that audiophiles have some competition in who can invent the most pointless things to split hairs over. The photo guys need to start taping magic rocks to their cameras to really keep up though.

The worst part is its often in areas people improperly understand the benefits and downsides. Biggest problem with good raw compression is you have a linear DNG, half processed essentially. Great, the file size is smaller, but now you miss data that processes like AI denoise can benefit from as the image is already debayered. On the flip side, good compression like DNG 1.7 spec's jpeg-xl compression is borderline mag…

I'm kind of surprised we haven't seen things like 16 bit luminence, 12 bit chromanance. (I guess to do that before debayering would require RGBW pixels or something like that)

Re: How does lossless compression in Fuji RAF files work? (2020)

#28

Post by scblock »

brnt wrote: post #13
manoDev wrote: post #7

Earlier quoted context omitted.

It’s because manufacturers keep inventing their own formats instead of using plain DNG, and you can only figure out the difference reverse engineering the file. Even for the same manufacturer and file type, they may change encoding details between models or firmware revisions. There are situations where they may decrease the bit depth of the final image if there’s not enough dynamic range, there are situations where…

How is DNG tooling these days? It's been ages since I checked, but it used have near zero support in (FLOSS) tools (including ffmpeg/imagemagick). You even had to use Adobe's Windows converter.

DNG is well supported by the typical raw libraries in my experience. My Ricoh records DNG natively, and I work with the results in rawtherapee and darktable. I am less sure about ffmpeg or imagemagick as I don't really automate raw processing.

Re: How does lossless compression in Fuji RAF files work? (2020)

#29

Post by Scaevolus »

matja wrote: post #4
vjvjvjvjghv wrote: post #2

There are always these crazy discussions in photo forums where people are arguing that uncompressed RAW files are better than lossless compressed.

Those discussions I feel are fuelled by manufacturers like Sony saying [0] things like: Lossless compressed RAW: ... This is a popular format that occupies less space with minimal quality loss. "minimal" "loss"? That's not "no loss", so what exactly is it? [0] https://www.sony.co.uk/electronics/support/articles/00257081

A lot of cameras write "lossless" to mean "perceptually lossless". This is easy to do because ~12-bit ADCs have lots of noise in the low order bits.

Re: How does lossless compression in Fuji RAF files work? (2020)

#30

Post by kjkjadksj »

yboulkaid wrote: post #16

I wonder if something about this explains why Fuji RAF files are the only RAW files that make Lightroom struggle. I never heard the fans on my M1 mac until I started processing those RAF files, they're not even that large but something about them makes Lightroom struggle. And judging by posts on photography forums, I'm not the only one either

Lightroom still is terrible for fuji raws from a worm standpoint. Almost looks like they use bilinear debayering. Dcraw is night and day better.
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