This topic is in the 2015 archive. You can read it and like its posts here. It is read only.
Archive 2015A7rII rumour
p.5 #1A7rII rumour
ecarlino wrote:
has anyone on any thread EVER pined for an UNCOMPRESSED RAW file?
The pining is for an end to lossy compression (and the artifacts that can arise) I think people would take whatever they could get, if it turned out that there were not enough resources to implement lossless compression.
ecarlino wrote:
I think the outtrade in our conversation is that you were referring to UNCOMPRESSED (not sure why) so I guess we can end the pissing match b/c I've always respected your posts so let's let this one go.....
I think I misread what you originally wrote and I made a mistake by not being specific in what I was referring to as lossless (as in without loss, artifacts etc.), I apologise for that. but I completely agree, We're both right just referring to different things, I agree enough has been said on this issue.
So apparently there's going to be some new Sony cameras soon...
has anyone on any thread EVER pined for an UNCOMPRESSED RAW file?
The pining is for an end to lossy compression (and the artifacts that can arise) I think people would take whatever they could get, if it turned out that there were not enough resources to implement lossless compression.
ecarlino wrote:
I think the outtrade in our conversation is that you were referring to UNCOMPRESSED (not sure why) so I guess we can end the pissing match b/c I've always respected your posts so let's let this one go.....
I think I misread what you originally wrote and I made a mistake by not being specific in what I was referring to as lossless (as in without loss, artifacts etc.), I apologise for that. but I completely agree, We're both right just referring to different things, I agree enough has been said on this issue.
So apparently there's going to be some new Sony cameras soon...
Mar 19, 2015 at 10:03 AM
p.5 #2A7rII rumour
Matt Grum wrote:
Lossy compression is not by definition more complex than lossless compression(e.g. truncating every 14 bit value to 8 bits is lossy compression). Also Sony's lossy compression algorithm doesn't use an entropy encoder, it is simpler than lossless JPEG which the other manufacturers use.
Source?
"Lossy compression is not by definition more complex than lossless compression"
It is; you're wrong. What languages do you code? Just curious. I don't see many coders on photography forums (primarily go/c++/asm here)
"We're both right just referring to different things"
He wasn't correct even if you were talking about lossless compression
Edited on Mar 19, 2015 at 10:17 AM · View previous versions
Lossy compression is not by definition more complex than lossless compression(e.g. truncating every 14 bit value to 8 bits is lossy compression). Also Sony's lossy compression algorithm doesn't use an entropy encoder, it is simpler than lossless JPEG which the other manufacturers use.
Source?
"Lossy compression is not by definition more complex than lossless compression"
It is; you're wrong. What languages do you code? Just curious. I don't see many coders on photography forums (primarily go/c++/asm here)
"We're both right just referring to different things"
He wasn't correct even if you were talking about lossless compression
Edited on Mar 19, 2015 at 10:17 AM · View previous versions
Mar 19, 2015 at 10:06 AM
p.5 #3A7rII rumour
Well hopefully the lossy vs lossless raw diversion has ended so we can get back to the meat of the rumors about the a7R II and (hopefully) a9.
So presently SAR is claiming the a7R II will indeed be much the same sort of upgrade as the a7 to a7 II was. Same ol' sensor in a new body with stabilization. Still a nice upgrade.
SAR is also claiming that a new 50 MP camera will be announced along with it. Hope it's the a9! Any reason why Sony would announce a 50 MP a-mount camera instead of e-mount? I would imagine Sony has a far larger potential profit potential for a 50 MP e-mount camera as it has the opportunity to siphon off a good number for potential Canon 5DS/5DS R buyers (who already have Canon-mount lenses they can use with relative ease on the e-mount system).
So presently SAR is claiming the a7R II will indeed be much the same sort of upgrade as the a7 to a7 II was. Same ol' sensor in a new body with stabilization. Still a nice upgrade.
SAR is also claiming that a new 50 MP camera will be announced along with it. Hope it's the a9! Any reason why Sony would announce a 50 MP a-mount camera instead of e-mount? I would imagine Sony has a far larger potential profit potential for a 50 MP e-mount camera as it has the opportunity to siphon off a good number for potential Canon 5DS/5DS R buyers (who already have Canon-mount lenses they can use with relative ease on the e-mount system).
Mar 19, 2015 at 10:13 AM
p.5 #4A7rII rumour
By the way, for those anal enough to want to learn more about compression. Cambridge uni has an awesome comp science programme 
Mar 19, 2015 at 10:16 AM
p.5 #5A7rII rumour
darbo wrote:
Well hopefully the lossy vs lossless raw diversion has ended so we can get back to the meat of the rumors about the a7R II and (hopefully) a9.
So presently SAR is claiming the a7R II will indeed be much the same sort of upgrade as the a7 to a7 II was. Same ol' sensor in a new body with stabilization. Still a nice upgrade.
SAR is also claiming that a new 50 MP camera will be announced along with it. Hope it's the a9! Any reason why Sony would announce a 50 MP a-mount camera instead of e-mount? I would...Show more →
The reason Sony might put the 50MP sensor into an a99 successor first might be:
1) To reassure any a-mount users left that Sony has not abandoned the system.
2) It will be far, far easier for Sony to offer a more competitive pro oriented model with better AF, faster frame rate and so on in a larger body with a separate PDAF module. I don't think the tech is far enough along yet with mirrorless FF otherwise. So, Sony could offer the best of both worlds in a single body if it is a-mount - high resolution, great AF and high FPS. Any Pro oriented body will be larger in any case so the size advantage of going with the E-mount might be sort of irrelevant in this instance versus the obvious technical advantages mentioned above.
Well hopefully the lossy vs lossless raw diversion has ended so we can get back to the meat of the rumors about the a7R II and (hopefully) a9.
So presently SAR is claiming the a7R II will indeed be much the same sort of upgrade as the a7 to a7 II was. Same ol' sensor in a new body with stabilization. Still a nice upgrade.
SAR is also claiming that a new 50 MP camera will be announced along with it. Hope it's the a9! Any reason why Sony would announce a 50 MP a-mount camera instead of e-mount? I would...Show more →
The reason Sony might put the 50MP sensor into an a99 successor first might be:
1) To reassure any a-mount users left that Sony has not abandoned the system.
2) It will be far, far easier for Sony to offer a more competitive pro oriented model with better AF, faster frame rate and so on in a larger body with a separate PDAF module. I don't think the tech is far enough along yet with mirrorless FF otherwise. So, Sony could offer the best of both worlds in a single body if it is a-mount - high resolution, great AF and high FPS. Any Pro oriented body will be larger in any case so the size advantage of going with the E-mount might be sort of irrelevant in this instance versus the obvious technical advantages mentioned above.
Mar 19, 2015 at 10:30 AM
p.5 #6A7rII rumour
Fletcha wrote:
Source?
Here's a source for the Sony lossy algorithm not using entropy encoding:
http://www.rawdigger.com/howtouse/sony-craw-arw2-posterization-detection
Fletcha wrote:
"Lossy compression is not by definition more complex than lossless compression"
It is; you're wrong.
The simplest lossy compression scheme I can think of is to simply throw away the least significant bits. That will a) reduce the storage requirement (fewer bits per pixel) and b) result in some loss of data. It is therefor a form of lossy compression.
The simplest lossless compression scheme would be something like run length encoding, which requires many more lines of code to implement than truncating a binary value, which is a single operation.
We're going way off topic here, so I think that's all I'm going to say on the subject.
Source?
Here's a source for the Sony lossy algorithm not using entropy encoding:
http://www.rawdigger.com/howtouse/sony-craw-arw2-posterization-detection
Fletcha wrote:
"Lossy compression is not by definition more complex than lossless compression"
It is; you're wrong.
The simplest lossy compression scheme I can think of is to simply throw away the least significant bits. That will a) reduce the storage requirement (fewer bits per pixel) and b) result in some loss of data. It is therefor a form of lossy compression.
The simplest lossless compression scheme would be something like run length encoding, which requires many more lines of code to implement than truncating a binary value, which is a single operation.
We're going way off topic here, so I think that's all I'm going to say on the subject.
Mar 19, 2015 at 10:33 AM
p.5 #7A7rII rumour
Seems like an A7RIi with a 50MP sensor is not enough to compete with the 50MP "Pro" models from Canon and Nikon. Pros generally need way better frame rates, ergonomics, weather sealing, AF speed, etc. etc.. Thus I would not think Sony would make a 50MP A7RII for this purpose. So to me keeping it at 36MP and using the D810 sensor (or maybe an slightly upgraded version) makes far more sense.
A 50MP A8 pro mirrorless that has a substantially different inner and outer design from the A7 series makes more sense as well as a 50MP A-mount - these would compete with Canon and Nikon 50MP offerings far better for typical "pro" work.
Having the A7 series available in three different MP counts makes sense to me - there are many many upgrade features still to add to any of the A7 models and still keep the MP count the same for each.
On the other hand what the heck do I know - Sony may have it's own twisted development path that may make no sense to any of us.
For me, just give me an A7RII with 36MP, IBIS, EFCS, far better mechanical shutter, A7II exterior ergonomics (or even better), improved weather resistance and perhaps even lossless RAW files.
EDIT: Oh, and make that EVF/LCD switching/control thing workable - i.e., put an EVF/LCD ON/OFF button on the body so I can quickly turn it on when I want and not waste battery power.
A 50MP A8 pro mirrorless that has a substantially different inner and outer design from the A7 series makes more sense as well as a 50MP A-mount - these would compete with Canon and Nikon 50MP offerings far better for typical "pro" work.
Having the A7 series available in three different MP counts makes sense to me - there are many many upgrade features still to add to any of the A7 models and still keep the MP count the same for each.
On the other hand what the heck do I know - Sony may have it's own twisted development path that may make no sense to any of us.
For me, just give me an A7RII with 36MP, IBIS, EFCS, far better mechanical shutter, A7II exterior ergonomics (or even better), improved weather resistance and perhaps even lossless RAW files.
EDIT: Oh, and make that EVF/LCD switching/control thing workable - i.e., put an EVF/LCD ON/OFF button on the body so I can quickly turn it on when I want and not waste battery power.
Mar 19, 2015 at 10:43 AM
p.5 #8A7rII rumour
Fletcha wrote:
By the way, for those anal enough to want to learn more about compression. Cambridge uni has an awesome comp science programme
Oh look, someone still in school making blanket statements about others being wrong... Ah to be back in academia again with all the cocksure personalities untested by any experience. Such fond memories...
Take a moment to climb out of the ivory tower into the real world. Most "lossy" compression used in RAW files is simply companding. So it is in fact ridiculously simple and far less complex than most lossless entropy based compression schemes. As someone already illustrated the Sony compression (much like Nikon) is just a compander.
So, to review. Lossy compression /= JPEG or MP3. Not all lossy compression involves domain transforms before quantization based on a psycho-visual or psycho-acoustic model. Some of it is as simple as a gamma curve.
And the beautiful part is that it doesn't matter what you code in to understand all this...
P.S. And of course most lossy compression routines are followed by lossless entropy based compressors. Making any statements about complexity fraught.
By the way, for those anal enough to want to learn more about compression. Cambridge uni has an awesome comp science programme
Oh look, someone still in school making blanket statements about others being wrong... Ah to be back in academia again with all the cocksure personalities untested by any experience. Such fond memories...
Take a moment to climb out of the ivory tower into the real world. Most "lossy" compression used in RAW files is simply companding. So it is in fact ridiculously simple and far less complex than most lossless entropy based compression schemes. As someone already illustrated the Sony compression (much like Nikon) is just a compander.
So, to review. Lossy compression /= JPEG or MP3. Not all lossy compression involves domain transforms before quantization based on a psycho-visual or psycho-acoustic model. Some of it is as simple as a gamma curve.
And the beautiful part is that it doesn't matter what you code in to understand all this...
P.S. And of course most lossy compression routines are followed by lossless entropy based compressors. Making any statements about complexity fraught.
Mar 19, 2015 at 11:41 AM
p.5 #9A7rII rumour
Sadly, the people clamoring for lossless, ultimate image quality, 50MP etc etc are already getting their way, I feel. Has anyone seen the size of the new FE lenses? What is the point of having a mirrorless system the same size as Nikon/Canon OVF systems? Sharp to the corners, OSS, huge IBIS bodies that drain more battery with every iteration... garbage I don't need or want from a FF mirrorless system.
Put me in the "want" category of a FF system that just sucks... crap corners, pancake lenses that smear, contrast AF or none at all (even better), plastic everything, NO IBIS, and for god sakes, the LOSSIEST algorithm Sony can scrape off the engineering floor. Why should I have to pay Leica 8K for the privilege of shooting shitty photos and garbage lenses (please no hate mail, this is tongue in cheek k)? Doesn't Sony get it?
Please god, anything for something small, rudimentary, FF, and cheaper than these new A7 bodies that get bigger, succumb to feature creep, and get higher in price with every iteration.
Put me in the "want" category of a FF system that just sucks... crap corners, pancake lenses that smear, contrast AF or none at all (even better), plastic everything, NO IBIS, and for god sakes, the LOSSIEST algorithm Sony can scrape off the engineering floor. Why should I have to pay Leica 8K for the privilege of shooting shitty photos and garbage lenses (please no hate mail, this is tongue in cheek k)? Doesn't Sony get it?
Please god, anything for something small, rudimentary, FF, and cheaper than these new A7 bodies that get bigger, succumb to feature creep, and get higher in price with every iteration.
Mar 19, 2015 at 11:51 AM
p.5 #11A7rII rumour
taran wrote:
Put me in the "want" category of a FF system that just sucks... crap corners, pancake lenses that smear, contrast AF or none at all (even better), plastic everything, NO IBIS, and for god sakes, the LOSSIEST algorithm Sony can scrape off the engineering floor. Why should I have to pay Leica 8K for the privilege of shooting shitty photos and garbage lenses (please no hate mail, this is tongue in cheek k)? Doesn't Sony get it?
Please god, anything for something small, rudimentary, FF, and cheaper than these new A7 bodies that get bigger, succumb to feature creep, and get...Show more →
I have one of those already...
Put me in the "want" category of a FF system that just sucks... crap corners, pancake lenses that smear, contrast AF or none at all (even better), plastic everything, NO IBIS, and for god sakes, the LOSSIEST algorithm Sony can scrape off the engineering floor. Why should I have to pay Leica 8K for the privilege of shooting shitty photos and garbage lenses (please no hate mail, this is tongue in cheek k)? Doesn't Sony get it?
Please god, anything for something small, rudimentary, FF, and cheaper than these new A7 bodies that get bigger, succumb to feature creep, and get...Show more →
I have one of those already...
Mar 19, 2015 at 12:17 PM
p.5 #12A7rII rumour
taran wrote:
Sadly, the people clamoring for lossless, ultimate image quality, 50MP etc etc are already getting their way, I feel.
Great! I hope we are getting our way.
If you don't really give a rip about ultimate image quality and want a teeny tiny system, why not just go with smaller sensor systems? Seems like the a6000 puts out amazing images in a tiny package. Lenses are smaller and cheaper. If you truly want to compromise image quality for the sake of minimal size why do you need a FF camera at all?
Sadly, the people clamoring for lossless, ultimate image quality, 50MP etc etc are already getting their way, I feel.
Great! I hope we are getting our way.
If you don't really give a rip about ultimate image quality and want a teeny tiny system, why not just go with smaller sensor systems? Seems like the a6000 puts out amazing images in a tiny package. Lenses are smaller and cheaper. If you truly want to compromise image quality for the sake of minimal size why do you need a FF camera at all?
Mar 19, 2015 at 12:18 PM
p.5 #13A7rII rumour
Fletcha wrote:
By the way, for those anal enough to want to learn more about compression. Cambridge uni has an awesome comp science programme
I'm guessing literacy is not an entry requirement?
Edited on Mar 19, 2015 at 12:23 PM · View previous versions
By the way, for those anal enough to want to learn more about compression. Cambridge uni has an awesome comp science programme
I'm guessing literacy is not an entry requirement?
Edited on Mar 19, 2015 at 12:23 PM · View previous versions
Mar 19, 2015 at 12:21 PM
p.5 #14A7rII rumour
taran wrote:
Sadly, the people clamoring for lossless, ultimate image quality, 50MP etc etc are already getting their way, I feel. Has anyone seen the size of the new FE lenses? What is the point of having a mirrorless system the same size as Nikon/Canon OVF systems? Sharp to the corners, OSS, huge IBIS bodies that drain more battery with every iteration... garbage I don't need or want from a FF mirrorless system.
Put me in the "want" category of a FF system that just sucks... crap corners, pancake lenses that smear, contrast AF or none at all (even better), plastic everything, NO...Show more →
I think m43 is calling your name then.
Sadly, the people clamoring for lossless, ultimate image quality, 50MP etc etc are already getting their way, I feel. Has anyone seen the size of the new FE lenses? What is the point of having a mirrorless system the same size as Nikon/Canon OVF systems? Sharp to the corners, OSS, huge IBIS bodies that drain more battery with every iteration... garbage I don't need or want from a FF mirrorless system.
Put me in the "want" category of a FF system that just sucks... crap corners, pancake lenses that smear, contrast AF or none at all (even better), plastic everything, NO...Show more →
I think m43 is calling your name then.
Mar 19, 2015 at 12:21 PM
p.5 #15A7rII rumour
darbo wrote:
So presently SAR is claiming the a7R II will indeed be much the same sort of upgrade as the a7 to a7 II was. Same ol' sensor in a new body with stabilization. Still a nice upgrade.
Put me down for one of those, please...
So presently SAR is claiming the a7R II will indeed be much the same sort of upgrade as the a7 to a7 II was. Same ol' sensor in a new body with stabilization. Still a nice upgrade.
Put me down for one of those, please...
Mar 19, 2015 at 12:26 PM
p.5 #16A7rII rumour
taran wrote:
Sadly, the people clamoring for lossless, ultimate image quality, 50MP etc etc are already getting their way, I feel. Has anyone seen the size of the new FE lenses? What is the point of having a mirrorless system the same size as Nikon/Canon OVF systems? Sharp to the corners, OSS, huge IBIS bodies that drain more battery with every iteration... garbage I don't need or want from a FF mirrorless system.
Put me in the "want" category of a FF system that just sucks... crap corners, pancake lenses that smear, contrast AF or none at all (even better), plastic everything, NO...Show more →
Mirrorless does not equate to small. There are many other advantages of a mirrorless system that have nothing to do with the size of the body. You can have a small mirrorless FX body that necessarily scrimps on features, ergonomics, etc. and you can have a large mirrorless FX body that is fully featured. Sony likely will be making both (A7rII and A9 or whatever it will be called).
I wish Nikon made an A7rII equivalent - i.e., 36MP mirrorless in an A7R-sized body, but the Nikon way. There are times when I want to carry and use small compact primes and times where I want full-on-pro performance and I don't expect them to be the same body.
Sadly, the people clamoring for lossless, ultimate image quality, 50MP etc etc are already getting their way, I feel. Has anyone seen the size of the new FE lenses? What is the point of having a mirrorless system the same size as Nikon/Canon OVF systems? Sharp to the corners, OSS, huge IBIS bodies that drain more battery with every iteration... garbage I don't need or want from a FF mirrorless system.
Put me in the "want" category of a FF system that just sucks... crap corners, pancake lenses that smear, contrast AF or none at all (even better), plastic everything, NO...Show more →
Mirrorless does not equate to small. There are many other advantages of a mirrorless system that have nothing to do with the size of the body. You can have a small mirrorless FX body that necessarily scrimps on features, ergonomics, etc. and you can have a large mirrorless FX body that is fully featured. Sony likely will be making both (A7rII and A9 or whatever it will be called).
I wish Nikon made an A7rII equivalent - i.e., 36MP mirrorless in an A7R-sized body, but the Nikon way. There are times when I want to carry and use small compact primes and times where I want full-on-pro performance and I don't expect them to be the same body.
Mar 19, 2015 at 12:27 PM
p.5 #17A7rII rumour
jhinkey wrote:
Put me in the "want" category of a FF system that just sucks... crap corners, pancake lenses that smear, contrast AF or none at all (even better), plastic everything, NO IBIS, and for god sakes, the LOSSIEST algorithm Sony can scrape off the engineering floor. Why should I have to pay Leica 8K for the privilege of shooting shitty photos and garbage lenses (please no hate mail, this is tongue in cheek k)? Doesn't Sony get it?
Please god, anything for something small, rudimentary, FF, and cheaper than these new A7 bodies that get bigger, succumb to feature creep, and get higher in price with every iteration.Mirrorless does not equate to small. There are many other advantages of a mirrorless system that have nothing to do with the size of the body. You can have a small mirrorless FX body that necessarily scrimps on features, ergonomics, etc. and you can have a large mirrorless FX body that is fully featured. Sony likely will be making both (A7rII and A9 or whatever it will be called).
I wish Nikon made an A7rII equivalent - i.e., 36MP mirrorless in an A7R-sized body, but the Nikon way. There are times when I want to carry and use small compact primes...Show more →
Is the "Nikon way" mean you get to send in the camera for quality control issues or maybe wait for the "10" version of the camera.
taran wrote
Sadly, the people clamoring for lossless, ultimate image quality, 50MP etc etc are already getting their way, I feel. Has anyone seen the size of the new FE lenses? What is the point of having a mirrorless system the same size as Nikon/Canon OVF systems? Sharp to the corners, OSS, huge IBIS bodies that drain more battery with every iteration... garbage I don't need or want from a FF mirrorless system.Put me in the "want" category of a FF system that just sucks... crap corners, pancake lenses that smear, contrast AF or none at all (even better), plastic everything, NO IBIS, and for god sakes, the LOSSIEST algorithm Sony can scrape off the engineering floor. Why should I have to pay Leica 8K for the privilege of shooting shitty photos and garbage lenses (please no hate mail, this is tongue in cheek k)? Doesn't Sony get it?
Please god, anything for something small, rudimentary, FF, and cheaper than these new A7 bodies that get bigger, succumb to feature creep, and get higher in price with every iteration.
I wish Nikon made an A7rII equivalent - i.e., 36MP mirrorless in an A7R-sized body, but the Nikon way. There are times when I want to carry and use small compact primes...Show more →
Is the "Nikon way" mean you get to send in the camera for quality control issues or maybe wait for the "10" version of the camera.
Mar 19, 2015 at 12:32 PM
p.5 #18A7rII rumour
Matt Grum wrote:
Here's a source for the Sony lossy algorithm not using entropy encoding:
http://www.rawdigger.com/howtouse/sony-craw-arw2-posterization-detection
It is; you're wrong.The simplest lossy compression scheme I can think of is to simply throw away the least significant bits. That will a) reduce the storage requirement (fewer bits per pixel) and b) result in some loss of data. It is therefor a form of lossy compression.
The simplest lossless compression scheme would be something like run length encoding, which requires many more lines of code to implement than truncating a binary value, which is a single operation.
We're going way off topic here, so I think that's all I'm...Show more →
"The simplest lossy compression scheme I can think of is to simply throw away the least significant bits. That will a) reduce the storage requirement (fewer bits per pixel) and b) result in some loss of data. It is therefor a form of lossy compression. "
You skipped the compression side of the algorithm. Truncation + compression > compression. Keep in mind we're talking about image compression.
"Here's a source for the Sony lossy algorithm not using entropy encoding"
It seems you've misunderstood the un-authoritative article. It does not contain the sony's source code; furthermore, it does not state entropy is not used. I suggest you look at patents.
http://pastebin.com/9TvedTK6
http://pastebin.com/VbLQnR6J
These two should help you understand a bit about compression.
molson wrote:
I'm guessing spelling and grammar are not entry requirements?
You're going to make fun when 1) Your post is grammatically incorrect 2) It was a simple typo? They are requirements, but surprisingly I don't spend much time thinking about the spelling and grammar of my posts; I care about the content as a whole; furthermore, "programme" is the correct word; Americans spell it "program" I believe. The full-stop was a typo. Your sentence is grammatically incorrect by the way. Your posts are littered with grammatical errors but it doesn't necessarily mean you are illiterate.
Clearly none of you code (and that is fine, it's a photography site) and you're not willing to listen to a coder. Dunning-kruger effect is obnoxious, as is the progressively worse posts. For that reason, I have no interest to post here any longer. I tried to educate you in a non condescending and offensive manner but children will be children.
I plan to code a custom firmware similar to magic lantern. Not as complex but it'll fix some of the issues I have with the a7r. I believe I can implement EFCS.
Peace out
Fletcha wrote
Source?http://www.rawdigger.com/howtouse/sony-craw-arw2-posterization-detection
Fletcha wrote
"Lossy compression is not by definition more complex than lossless compression"It is; you're wrong.
The simplest lossless compression scheme would be something like run length encoding, which requires many more lines of code to implement than truncating a binary value, which is a single operation.
We're going way off topic here, so I think that's all I'm...Show more →
"The simplest lossy compression scheme I can think of is to simply throw away the least significant bits. That will a) reduce the storage requirement (fewer bits per pixel) and b) result in some loss of data. It is therefor a form of lossy compression. "
You skipped the compression side of the algorithm. Truncation + compression > compression. Keep in mind we're talking about image compression.
"Here's a source for the Sony lossy algorithm not using entropy encoding"
It seems you've misunderstood the un-authoritative article. It does not contain the sony's source code; furthermore, it does not state entropy is not used. I suggest you look at patents.
http://pastebin.com/9TvedTK6
http://pastebin.com/VbLQnR6J
These two should help you understand a bit about compression.
molson wrote:
Fletcha wrote
By the way, for those anal enough to want to learn more about compression. Cambridge uni has an awesome comp science programmeYou're going to make fun when 1) Your post is grammatically incorrect 2) It was a simple typo? They are requirements, but surprisingly I don't spend much time thinking about the spelling and grammar of my posts; I care about the content as a whole; furthermore, "programme" is the correct word; Americans spell it "program" I believe. The full-stop was a typo. Your sentence is grammatically incorrect by the way. Your posts are littered with grammatical errors but it doesn't necessarily mean you are illiterate.
Clearly none of you code (and that is fine, it's a photography site) and you're not willing to listen to a coder. Dunning-kruger effect is obnoxious, as is the progressively worse posts. For that reason, I have no interest to post here any longer. I tried to educate you in a non condescending and offensive manner but children will be children.
I plan to code a custom firmware similar to magic lantern. Not as complex but it'll fix some of the issues I have with the a7r. I believe I can implement EFCS.
Peace out
Mar 19, 2015 at 12:51 PM
p.5 #19A7rII rumour
Matt Grum wrote:
It apparently is for the Nikon bodies that offer it as an option. It seems perfectly viable if lossless compression is causing your cameras to overheat.
There are a couple of things wrong with this claim "you are INCORRECT to suggest that LOSSY requires more computation than LOSSLESS. the advantages to designers of using LOSSY over LOSSLESS are: simpler computation and smaller resulting file size."
1) Lossy by definition is more complex; it requires additional preprocessing
2) The claim that designers use lossy over lossless for "simpler computation" is erroneous.Lossy compression is not by definition more complex than lossless compression(e.g. truncating every 14 bit value to 8 bits is lossy compression). Also Sony's lossy compression algorithm doesn't use an entropy encoder, it is simpler than lossless JPEG which the other manufacturers use.
It's a shame that Sony is so stubborn. Even Samsung switched to lossless compressed RAW files a couple of years ago (on all their cameras, through simple firmware upgrade). Write times decreased in direct correlation to the files size. The only reason I see Sony sticking with their format is because their camera specs look better for FPS and write times. What a shame
Samsung now plans plans to make all options available to the user in their next firmware update. Samsung listened to users and went from uncompressed RAW's and lossles compressed RAW files. Now they will let the USER decide what they want: uncompressed, loss-less compressed, or lossy compressed.
Fletcha wrote
Uncompressed is not viable.Fletcha wrote
Typically speaking, if the truncation of data is substantially large, the entropy encoder has to do a bit less work (this applies to most but not all compression algorithms); however, the overall computation is more complex; in addition, the additional preprocessing loads a processor.There are a couple of things wrong with this claim "you are INCORRECT to suggest that LOSSY requires more computation than LOSSLESS. the advantages to designers of using LOSSY over LOSSLESS are: simpler computation and smaller resulting file size."
1) Lossy by definition is more complex; it requires additional preprocessing
2) The claim that designers use lossy over lossless for "simpler computation" is erroneous.
It's a shame that Sony is so stubborn. Even Samsung switched to lossless compressed RAW files a couple of years ago (on all their cameras, through simple firmware upgrade). Write times decreased in direct correlation to the files size. The only reason I see Sony sticking with their format is because their camera specs look better for FPS and write times. What a shame
Samsung now plans plans to make all options available to the user in their next firmware update. Samsung listened to users and went from uncompressed RAW's and lossles compressed RAW files. Now they will let the USER decide what they want: uncompressed, loss-less compressed, or lossy compressed.
Mar 19, 2015 at 01:10 PM
p.5 #20A7rII rumour
darbo wrote:
why do you need a FF camera at all?
Of course you are right, and I am prejudiced because I hate DSLR style bodies, but I can think of three reasons:
1) Bigger prints
2) 35mm lenses at their native focal length
3) DOF
To achieve the above with sub FF systems requires some trickeration. Also, since my subjects don't ever need AF, there are a billion 35mm lenses that are cheap as chips which I would love to work thru/adapt, those lenses are crap anyway, so a perfect sensor or IBIS is really not a consideration.
why do you need a FF camera at all?
Of course you are right, and I am prejudiced because I hate DSLR style bodies, but I can think of three reasons:
1) Bigger prints
2) 35mm lenses at their native focal length
3) DOF
To achieve the above with sub FF systems requires some trickeration. Also, since my subjects don't ever need AF, there are a billion 35mm lenses that are cheap as chips which I would love to work thru/adapt, those lenses are crap anyway, so a perfect sensor or IBIS is really not a consideration.
Mar 19, 2015 at 01:20 PM