Re: [Gimp-developer] JPEG quality factor - some remaining odds and ends

2010-01-20 Thread gg
On 01/19/10 22:51, Liam R E Quin wrote: On Tue, 2010-01-19 at 22:38 +0100, yahvuu wrote: [...] II. Range of actually useful values for IJG quality value For GIMP's target users less than half of all possible settings are useful: possibly - I've often used values as low as 35% or

Re: [Gimp-developer] JPEG quality factor - some remaining odds and ends

2010-01-20 Thread Torsten Neuer
Once a user starts to use jpeg they have to decide what to do with quality setting. Bigger number = better quality is not too hard to get your head around. A bit of experimenting quickly reveals what works best for a particular task. You quickly realise what ranges don't fit your needs and

Re: [Gimp-developer] JPEG quality factor - some remaining odds and ends

2010-01-20 Thread yahvuu
Liam R E Quin wrote: On Tue, 2010-01-19 at 22:38 +0100, yahvuu wrote: [...] II. Range of actually useful values for IJG quality value For GIMP's target users less than half of all possible settings are useful: possibly - I've often used values as low as 35% or sometimes lower. The

Re: [Gimp-developer] JPEG quality factor - some remaining odds and ends

2010-01-19 Thread Liam R E Quin
On Tue, 2010-01-19 at 22:38 +0100, yahvuu wrote: [...] II. Range of actually useful values for IJG quality value For GIMP's target users less than half of all possible settings are useful: possibly - I've often used values as low as 35% or sometimes lower. The sweet spot depends hugely

Re: [Gimp-developer] JPEG quality factor - some remaining odds and ends

2010-01-19 Thread Jon Senior
On Tue, 19 Jan 2010 22:38:40 +0100 yahvuu yah...@gmail.com wrote: II. Range of actually useful values for IJG quality value For GIMP's target users less than half of all possible settings are useful: http://yahvuu.files.wordpress.com/2009/08/ijgqualityrange.png or, in ASCII:

Re: [Gimp-developer] JPEG quality factor - some remaining odds and ends

2010-01-19 Thread Scott
On Tue, Jan 19, 2010 at 10:38:40PM +0100, yahvuu wrote: Hi all, recent discussion on gimp-user brought up some usuability issues of the JPEG export dialog [1]. Actually, there's nothing new to say about it... the big JPEG quality thread did cover it all [2]. However, due to the sheer size

Re: [Gimp-developer] jpeg quality factor

2007-07-14 Thread gg
On Fri, 13 Jul 2007 00:03:18 +0200, Chris Mohler [EMAIL PROTECTED] wrote: I'll try to follow the analogy without this becoming rediculous: In this analogy, the new GIMP Hammer would auto-provide a nail (since the nail is clearly better). The carpenter would flip the GIMP hammer around and

Re: [Gimp-developer] jpeg quality factor

2007-07-14 Thread David Gowers
On 7/14/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: On Fri, 13 Jul 2007 00:03:18 +0200, Chris Mohler [EMAIL PROTECTED] wrote: I'll try to follow the analogy without this becoming rediculous: [misrepresentation and reactiveness cut] We all know that jpeg is lossy. You use it with suitable

Re: [Gimp-developer] jpeg quality factor

2007-07-13 Thread saulgoode
Quoting [EMAIL PROTECTED]: On Tue, 10 Jul 2007 19:21:33 +0200, [EMAIL PROTECTED] wrote: No. If you want to specify something other than a user-specified default for an acceptable level of quality while editing in the GIMP (for example, overriding it with an image-specific value), that is

Re: [Gimp-developer] jpeg quality factor

2007-07-13 Thread gg
On Fri, 13 Jul 2007 20:49:49 +0200, [EMAIL PROTECTED] wrote: I fail to see how I have misused the term default in any of this explanation. Sorry , apparently you missed the other post where I explained this more fully, I assumed everyone who was following this was reading the posts. The

Re: [Gimp-developer] jpeg quality factor

2007-07-13 Thread Raphaël Quinet
On Fri, 13 Jul 2007 22:42:29 +0200, [EMAIL PROTECTED] wrote: On Fri, 13 Jul 2007 20:49:49 +0200, [EMAIL PROTECTED] wrote: I fail to see how I have misused the term default in any of this explanation. [...] When an image already has a value for jpeg_quality , or any other paramter,

Re: [Gimp-developer] jpeg quality factor

2007-07-13 Thread Valerie VK
How about creating the following buttons on the jpeg save console? - Save at original image compression value - Save at user-specified compression value (insert current value of used-specified quality) - Change user-specified compression value It can be abbreviated as the following: Save at the

Re: [Gimp-developer] jpeg quality factor.

2007-07-12 Thread peter sikking
Raphaël wrote: let's see how short I can keep this. We also have to be humble and remember that writing down the current vision only took us a couple of hours, not 5 years (basically one hour of discussion at LGM plus some e-mail exchanges while we were polishing the minutes). Two hours.

Re: [Gimp-developer] jpeg quality factor.

2007-07-12 Thread Sven Neumann
Hi, On Thu, 2007-07-12 at 13:29 +0200, peter sikking wrote: Two hours. The vision has been simmering in the back of the minds of everybody involved for all the years that they have been working on GIMP. If you are now interpreting this vision that way that GIMP is not meant to be used for

Re: [Gimp-developer] jpeg quality factor.

2007-07-12 Thread peter sikking
Akkana wrote: I'm seeing an unspoken assumption in this thread that most photos are edited in multiple sessions: read into gimp, do a few operations, write to disk, read back in (perhaps hours or days later), do a few more operations, write back out, repeat. I was more thinking from the

Re: [Gimp-developer] jpeg quality factor.

2007-07-12 Thread Raphaël Quinet
Let me also try to keep this (relatively) short. I'm not good at this. :-) On Thu, 12 Jul 2007 13:29:49 +0200, peter sikking [EMAIL PROTECTED] wrote: I take the vision as broad as it can be explained (it was phrased not so specific for a reason), but not broader. That's certainly fine. But

Re: [Gimp-developer] jpeg quality factor.

2007-07-12 Thread Raphaël Quinet
On Thu, 12 Jul 2007 14:31:16 +0200, Raphaël Quinet [EMAIL PROTECTED] wrote: Let me also try to keep this (relatively) short. I'm not good at this. :-) I could have made it much shorter. Summary: 1) Our vision focuses on a minority of GIMP users (experienced users, or those who need

Re: [Gimp-developer] jpeg quality factor

2007-07-12 Thread gg
On Tue, 10 Jul 2007 19:21:33 +0200, [EMAIL PROTECTED] wrote: No. If you want to specify something other than a user-specified default for an acceptable level of quality while editing in the GIMP (for example, overriding it with an image-specific value), that is when you should use Save As.

Re: [Gimp-developer] jpeg quality factor

2007-07-12 Thread Chris Mohler
Sorry - I always forget to Reply-All to this list... On 7/12/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: [...] GIMP IS A TOOL, NOT A TUTORIAL. Take an analogy: A builder needs to nail a piece of wood as a guide but all the nails he has to hand are too big. To get round the problem he

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread David Gowers
On 7/10/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: On Tue, 10 Jul 2007 00:46:44 +0200, peter sikking [EMAIL PROTECTED] wrote: Really? Let's have a look at the product vision. 'High-end' is the word I want us to focus on. Please dont distort this by taking one word out of context.

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread Chris Mohler
On 7/9/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: On Tue, 10 Jul 2007 02:08:45 +0200, Chris Mohler [EMAIL PROTECTED] wrote: I expect the Save command to retain *all* data: not just some. If you expect that when using jpeg you are wrong and need to see the first use warning that has

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread Graeme Gill
Chris Mohler wrote: I understand that JPEG drops data. My point: in most applications, 'save' means save your data. In the image editing world, 'save' has come to mean save as much data as you want given the limitations of the format - here are (or might be) some options. One view is that

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread jernej
On Tuesday, July 10, 2007, 8:09:04, Chris Mohler wrote: I understand that JPEG drops data. My point: in most applications, 'save' means save your data. In the image editing world, 'save' has come to mean save as much data as you want given the limitations of the format - here are (or might

Re: [Gimp-developer] jpeg quality factor

2007-07-10 Thread saulgoode
Quoting [EMAIL PROTECTED]: On Tue, 10 Jul 2007 01:24:40 +0200, [EMAIL PROTECTED] wrote: If I have a Quality setting of 95 and I load an image that was saved with a Q=50, I should be very disappointed if the GIMP degraded to that level when I have specified that I expect less loss when

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread peter sikking
gg, my dear agent provocateur, creating interaction requires making hard choices, because you cannot make an application for everybody. For that you use the product vision that you set as a team at the beginning of the project. And then you don't fudge when the moment is there. You make hard

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread Raphaël Quinet
On Tue, 10 Jul 2007 12:29:23 +0200, peter sikking [EMAIL PROTECTED] wrote: creating interaction requires making hard choices, because you cannot make an application for everybody. For that you use the product vision that you set as a team at the beginning of the project. And then you don't

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread peter sikking
Raphaël wrote: creating interaction requires making hard choices, because you cannot make an application for everybody. For that you use the product vision that you set as a team at the beginning of the project. And then you don't fudge when the moment is there. I would like to temper this

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread Michael Schumacher
Von: Raphaël Quinet [EMAIL PROTECTED] We also have to be humble and remember that writing down the current vision only took us a couple of hours, not 5 years (basically one hour of discussion at LGM plus some e-mail exchanges while we were polishing the minutes). ... plus the better part of

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread Michael Schumacher
Von: Michael Schumacher [EMAIL PROTECTED] Kanila's Kamila, sorry for misspelling your name. Michael -- GMX FreeMail: 1 GB Postfach, 5 E-Mail-Adressen, 10 Free SMS. Alle Infos und kostenlose Anmeldung: http://www.gmx.net/de/go/freemail ___

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread Raphaël Quinet
On Tue, 10 Jul 2007 16:32:11 +0200, peter sikking [EMAIL PROTECTED] wrote: Raphaël wrote: I would like to temper this a bit (not agent provocateur as gg, but maybe devil's advocate): a team that is too rigid about its vision and never adapts it over time runs a real risk of becoming

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread Raphaël Quinet
On Tue, 10 Jul 2007 00:46:44 +0200, peter sikking [EMAIL PROTECTED] wrote: There is also a real benefit in opening a jpeg and then saving the result in another (GIMP) file. We see from the explanations in this thread that opening a jpeg and then saving it again means a loss of information. So

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread Raphaël Quinet
On Tue, 10 Jul 2007 18:26:38 +0200, Michael Schumacher [EMAIL PROTECTED] wrote: Von: Raphaël Quinet [EMAIL PROTECTED] We also have to be humble and remember that writing down the current vision only took us a couple of hours, not 5 years (basically one hour of discussion at LGM plus some

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread Akkana Peck
peter sikking writes: But in between, as long as it is not finished, there is no role for jpeg. Only one decompression at the beginning and a compression of the end result is defendable in high-end graphics. I'm seeing an unspoken assumption in this thread that most photos are edited in

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread Raphaël Quinet
On Tue, 10 Jul 2007 09:51:24 -0700, Akkana Peck [EMAIL PROTECTED] wrote: Another thing I'm unclear on in this thread: when I first heard the idea of forcing Export instead of Save, the plan seemed to be that Save would always save XCF, and anything else would require Export. But now you seem

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread Alexandre Prokoudine
On 7/10/07, Raphaël Quinet wrote: GIMP parasites, etc. In fact, even the current XCF loses some information if you consider that it does not record the full undo history and the current tool contexts, but this is something that most users accept. They really do? Alexandre

Re: [Gimp-developer] jpeg quality factor

2007-07-10 Thread saulgoode
Quoting [EMAIL PROTECTED]: On Tue, 10 Jul 2007 01:24:40 +0200, [EMAIL PROTECTED] wrote: If I have a Quality setting of 95 and I load an image that was saved with a Q=50, I should be very disappointed if the GIMP degraded to that level when I have specified that I expect less loss when

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread Sven Neumann
On Mon, 2007-07-09 at 18:37 -0400, Liam R E Quin wrote: For my part I miss save a copy as... which in some programs saves the file like Save As but doesn't change the filename of what's being edited. GIMP 2.3 has this feature for quite a while already. I wonder if it'd be possible, for gimp

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread Guillermo Espertino
So I broke my promess. creating interaction requires making hard choices, because you cannot make an application for everybody. I have to agree. A good UI doesn't do what users ask. It does what is better for the users. ;-) This approach of taking the lossy format to an import/export section

Re: [Gimp-developer] jpeg quality factor.

2007-07-10 Thread Liam R E Quin
On Tue, 2007-07-10 at 19:41 +0200, Sven Neumann wrote: On Mon, 2007-07-09 at 18:37 -0400, Liam R E Quin wrote: For my part I miss save a copy as... which in some programs saves the file like Save As but doesn't change the filename of what's being edited. GIMP 2.3 has this feature for

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread Sven Neumann
Hi, On Sun, 2007-07-08 at 19:15 -0400, guepe wrote: In fact, my patch... does exactly that : if defaults settings are already saved, jpeg is saved with the parasites one (erasing the hardcoded ones). If no settings have been saved, then hardcoded are used. There is another player in the

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread Sven Neumann
Moin, On Mon, 2007-07-09 at 00:03 +0200, Sven Neumann wrote: The JPEG plug-in should not use the last-used values when being run non-interactively from the Save action. It should use the, now user-configurable, default values. Of course if the jpeg-save-options parasite is set on the image

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread gg
On Mon, 09 Jul 2007 08:14:29 +0200, Sven Neumann [EMAIL PROTECTED] wrote: Hi, On Sun, 2007-07-08 at 19:15 -0400, guepe wrote: In fact, my patch... does exactly that : if defaults settings are already saved, jpeg is saved with the parasites one (erasing the hardcoded ones). If no settings

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread Tor Lillqvist
Sven Neumann writes: If someone wants to try to recover some of the JPEG save settings when loading the JPEG file, feel free. There are some scenarios in which blindly reusing the quality factor guesstimated from loading an image is not a good idea, even if the guesstimate is very accurate.

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread Tor Lillqvist
Sven Neumann writes: If someone wants to try to recover some of the JPEG save settings when loading the JPEG file, feel free. I did. Index: plug-ins/jpeg/jpeg-load.c === --- plug-ins/jpeg/jpeg-load.c (revision 22905) +++

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread Raphaël Quinet
On Mon, 9 Jul 2007 17:32:29 +0300, Tor Lillqvist [EMAIL PROTECTED] wrote: Sven Neumann writes: If someone wants to try to recover some of the JPEG save settings when loading the JPEG file, feel free. I did. Thanks for this very nice patch! It would be even better to do the same for the

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread peter sikking
guys, what a thread. I say that the solution for all this lies in treating these lossy (my spell-checker proposes lousy) formats the same we are (gonna) handle indexed mode: import + export only. This would prevent the misunderstanding that there is a continuous lossless workflow for these type

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread Raphaël Quinet
On Mon, 9 Jul 2007 17:54:29 +0200, peter sikking [EMAIL PROTECTED] wrote: guys, what a thread. I say that the solution for all this lies in treating these lossy (my spell-checker proposes lousy) formats the same we are (gonna) handle indexed mode: import + export only. Eek! That would

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread Michael Schumacher
Von: Raphaël Quinet [EMAIL PROTECTED] On Mon, 9 Jul 2007 17:54:29 +0200, peter sikking [EMAIL PROTECTED] wrote: guys, what a thread. I say that the solution for all this lies in treating these lossy (my spell-checker proposes lousy) formats the same we are (gonna) handle indexed

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread Sven Neumann
Hi, On Mon, 2007-07-09 at 18:42 +0200, Raphaël Quinet wrote: Side note: as suggested by Sven in #gimp, I just had a look at ImageMagick to try and find out how they retreive or guess the quality settings from JPEG files. The code is about 100 lines long and can be found in

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread Guillermo Espertino
There is another player in the game and that's the last-used values stored with gimp_[gs]et_data(). And that's what has bitten Guillermo. He has saved an image as JPEG with low quality settings. No, I haven't. Since I know the problem I'm using always save as with quality=95 but it's still

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread Sven Neumann
Hi, On Mon, 2007-07-09 at 09:42 +0200, [EMAIL PROTECTED] wrote: Ha, cross post . Cross post? Huh? Btw, is it intentional that you are mailing from two (or three) different accounts and never put your real name in the From field? I find the use of two accounts annoying and the lack of a real

Re: [Gimp-developer] jpeg quality factor

2007-07-09 Thread Scott
On Sun, Jul 08, 2007 at 09:59:18AM -0400, Robert L Krawitz wrote: Think of the quality setting as an indication of expectations rather than a specific outcome. It may not be possible to get the exact same outcome (and obviously -- at least to us -- there's no way to retroactively improve

Re: [Gimp-developer] jpeg quality factor

2007-07-09 Thread Sven Neumann
Hi, On Mon, 2007-07-09 at 11:36 -0600, Scott wrote: Just curious, what would be so wrong with saving the original file as a backup before doing a destructive save? Emacs only bites me when I'm *really* stupid There's nothing wrong with that. It's even on the list of things that the file

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread gg
On Mon, 09 Jul 2007 19:32:14 +0200, Sven Neumann [EMAIL PROTECTED] wrote: Btw, is it intentional that you are mailing from two (or three) different accounts No it's not intentional. I share this email client which has several accounts configured. Occassionally I hit reply and fail to notice

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread Guillermo Espertino
Scott wrote: I am so glad that Guillermo stuck by his guns and apparently *finally* got the developers to realise the illogic of this feature. Scott: Please keep in mind that I was trying to collaborate, not to fight. In these cases is very common to see differences of criteria and some rough

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread gg
On Mon, 09 Jul 2007 17:54:29 +0200, peter sikking [EMAIL PROTECTED] wrote: guys, what a thread. das stimmt! I say that the solution for all this lies in treating these lossy (my spell-checker proposes lousy) formats the same we are (gonna) handle indexed mode: import + export only. I

Re: [Gimp-developer] jpeg quality factor

2007-07-09 Thread Scott
On Mon, Jul 09, 2007 at 08:18:44PM +0200, Sven Neumann wrote: Hi, On Mon, 2007-07-09 at 11:36 -0600, Scott wrote: Just curious, what would be so wrong with saving the original file as a backup before doing a destructive save? Emacs only bites me when I'm *really* stupid There's

Re: [Gimp-developer] jpeg quality factor

2007-07-09 Thread Sven Neumann
Hi, On Mon, 2007-07-09 at 14:07 -0600, Scott wrote: If more users would be so persistent, as you call it, then there would probably not a single developer left who would feel that developing GIMP is fun. There would probably be noone who would be willing to spend his/her free time on it.

Re: [Gimp-developer] jpeg quality factor

2007-07-09 Thread Scott
I was refering to your reply which was discouraging and completely needless. And so was your second reply. sorry to bother. The happy user is silent. Is that from the Book of Tao, or what? I like it. I shall remain silent. The silent user is happy (or unhappy - who knows?). Scott Swanson

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread gg
On Mon, 09 Jul 2007 11:33:34 +0200, Tor Lillqvist [EMAIL PROTECTED] wrote: There are some scenarios in which blindly reusing the quality factor guesstimated from loading an image is not a good idea, even if the guesstimate is very accurate. (Which happens when the loaded image's quantization

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread Liam R E Quin
On Sun, 2007-07-08 at 12:19 +0200, Sven Neumann wrote: [...] Due to the way file plug-ins are implemented in GIMP, it is not trivial to do this. But you can easily work around it by assigning Ctrl-S to Save As. I'd advise making ^S to be Quit. Then you'll be prompted, realise your mistake,

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread peter sikking
Raphaël wrote: I say that the solution for all this lies in treating these lossy (my spell-checker proposes lousy) formats the same we are (gonna) handle indexed mode: import + export only. Eek! That would significantly break the flow for what must be the most common image format for

Re: [Gimp-developer] jpeg quality factor

2007-07-09 Thread saulgoode
Quoting Sven Neumann [EMAIL PROTECTED]: ... The happy user is silent. If we would do a change every time a user asks for a change, then GIMP would be a lot more inconsistent and probably also more buggy. For that reason it is important to

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread Graeme Gill
On Mon, 09 Jul 2007 11:33:34 +0200, Tor Lillqvist [EMAIL PROTECTED] wrote: There are some scenarios in which blindly reusing the quality factor guesstimated from loading an image is not a good idea, even if the guesstimate is very accurate. (Which happens when the loaded image's quantization

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread Chris Mohler
At the risk of lengthening this thread... :) I agree with Peter - saving in a lossy format is a last-step operation in a good workflow. I respect the case of simple tweak and saving, but in the long run, all users should never being able to choose save and then lose data. I expect the Save

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread gg
On Tue, 10 Jul 2007 00:46:44 +0200, peter sikking [EMAIL PROTECTED] wrote: Raphaël wrote: I say that the solution for all this lies in treating these lossy (my spell-checker proposes lousy) formats the same we are (gonna) handle indexed mode: import + export only. Eek! That would

Re: [Gimp-developer] jpeg quality factor

2007-07-09 Thread gg
On Tue, 10 Jul 2007 01:24:40 +0200, [EMAIL PROTECTED] wrote: If I have a Quality setting of 95 and I load an image that was saved with a Q=50, I should be very disappointed if the GIMP degraded to that level when I have specified that I expect less loss when saving. It would NOT degrade it

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread gg
On Tue, 10 Jul 2007 01:58:50 +0200, Graeme Gill [EMAIL PROTECTED] wrote: On Mon, 09 Jul 2007 11:33:34 +0200, Tor Lillqvist [EMAIL PROTECTED] wrote: There are some scenarios in which blindly reusing the quality factor guesstimated from loading an image is not a good idea, even if the

Re: [Gimp-developer] jpeg quality factor.

2007-07-09 Thread gg
On Tue, 10 Jul 2007 02:08:45 +0200, Chris Mohler [EMAIL PROTECTED] wrote: I expect the Save command to retain *all* data: not just some. If you expect that when using jpeg you are wrong and need to see the first use warning that has been suggested. Assuming you do have some knowlege of

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread gg
On Sun, 08 Jul 2007 07:22:24 +0200, Guillermo Espertino [EMAIL PROTECTED] wrote: In Gimp, it saves the file directly, without asking for the compression setting. Result: an image over-compressed with artifacts. Smaller size than the original. In Photoshop, it shows the quality settings

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Øyvind Kolås
On 7/8/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: On Sat, 07 Jul 2007 21:38:57 +0200, Øyvind Kolås [EMAIL PROTECTED] wrote: the image used in the JPEG Generation Loss figure in the example in the following text uses an image that shows how JPEG compression keeps different aspects of

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Sven Neumann
Hi, On Sat, 2007-07-07 at 22:13 -0300, Guillermo Espertino wrote: Back to the topic: I propose to display the quality settings when an image is resaved as jpeg for the first time, if it's possible. I don't know how it's done, but when I take my image to PS from my camera, it asks me to

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread gg
On Sun, 08 Jul 2007 12:10:30 +0200, Øyvind Kolås [EMAIL PROTECTED] wrote: But a full decode/encode/decode cycle of JPEG / DV / MJPEG etc will accumulate more and more errors/artifacts. This accumulated error would be smaller with a higher default quality though. /Øyvind K. -- Obviously

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Øyvind Kolås
On 7/8/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: You clearly know more about the detail of this than I do but isn't there a direct one-to-one mapping once the original compression is done? Nope. Any deviation from that must be errors in the decoding, so is what you posted a symptom of

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Robert L Krawitz
Date: Sun, 08 Jul 2007 11:44:17 +0200 From: [EMAIL PROTECTED] On Sun, 08 Jul 2007 07:22:24 +0200, Guillermo Espertino [EMAIL PROTECTED] wrote: In Gimp, it saves the file directly, without asking for the compression setting. Result: an image over-compressed with

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Sven Neumann
Hi, On Sun, 2007-07-08 at 08:17 -0400, Robert L Krawitz wrote: Note that GIMP is not the only application that does this; Why should any application do what you suggest? If you open a JPEG file and save it again as JPEG, then the original quality factor is completely irrelevant. You are doing

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread gg
On Sun, 08 Jul 2007 14:35:30 +0200, Sven Neumann [EMAIL PROTECTED] wrote: Hi, On Sun, 2007-07-08 at 08:17 -0400, Robert L Krawitz wrote: Note that GIMP is not the only application that does this; Why should any application do what you suggest? If you open a JPEG file and save it again as

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Sven Neumann
Hi, On Sun, 2007-07-08 at 14:53 +0200, [EMAIL PROTECTED] wrote: Does your reply indicate you take a this feature not a bug approach here and you think is the best way gimp should deal with this situation? Indeed. When you open a JPEG file, then you have a decoded image. The settings that

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread gg
On Sun, 08 Jul 2007 15:12:03 +0200, Sven Neumann [EMAIL PROTECTED] wrote: Hi, On Sun, 2007-07-08 at 14:53 +0200, [EMAIL PROTECTED] wrote: Does your reply indicate you take a this feature not a bug approach here and you think is the best way gimp should deal with this situation? Indeed.

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Robert L Krawitz
From: Sven Neumann [EMAIL PROTECTED] Date: Sun, 08 Jul 2007 15:12:03 +0200 On Sun, 2007-07-08 at 14:53 +0200, [EMAIL PROTECTED] wrote: Does your reply indicate you take a this feature not a bug approach here and you think is the best way gimp should deal with this situation?

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread David Gowers
On 7/8/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: On Sun, 08 Jul 2007 15:12:03 +0200, Sven Neumann [EMAIL PROTECTED] wrote: Hi, On Sun, 2007-07-08 at 14:53 +0200, [EMAIL PROTECTED] wrote: Does your reply indicate you take a this feature not a bug approach here and you think is

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Robert L Krawitz
Date: Mon, 9 Jul 2007 00:26:21 +0930 From: David Gowers [EMAIL PROTECTED] On 7/8/07, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: On Sun, 08 Jul 2007 15:12:03 +0200, Sven Neumann [EMAIL PROTECTED] wrote: Hi, On Sun, 2007-07-08 at 14:53 +0200, [EMAIL PROTECTED] wrote:

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Roel Schroeven
Sven Neumann schreef: Hi, On Sun, 2007-07-08 at 14:53 +0200, [EMAIL PROTECTED] wrote: Does your reply indicate you take a this feature not a bug approach here and you think is the best way gimp should deal with this situation? Indeed. When you open a JPEG file, then you have a decoded

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread gg
On Sun, 08 Jul 2007 19:55:30 +0200, Sven Neumann [EMAIL PROTECTED] wrote: Hi, On Sun, 2007-07-08 at 17:37 +0200, Roel Schroeven wrote: 2. read the quality when loading a jpeg, and used that to save the image (if save as is not used). Last time we discussed this (a couple of years ago),

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Sven Neumann
Hi, On Sun, 2007-07-08 at 17:37 +0200, Roel Schroeven wrote: 2. read the quality when loading a jpeg, and used that to save the image (if save as is not used). Last time we discussed this (a couple of years ago), libjpeg didn't allow us to read the JPEG quality factor that was used to save

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread gg
On Sun, 08 Jul 2007 17:37:28 +0200, Roel Schroeven [EMAIL PROTECTED] wrote: 1. open a.jpg 2. save a.jpg - a.jpg is saved with the default quality, 85. Fine by me. 3. save a.jpg with save as, with quality say 55 - as expected it is saved with quality 55. 4. open b.jpg 5. save b.jpg -

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread gg
On Sun, 08 Jul 2007 17:53:59 +0200, Robert L Krawitz [EMAIL PROTECTED] wrote: What about the case where the original quality was 96 or 98, and it's resaved at the same quality level? My quick test showed a slight decrease in file size, but probably very little in the way of image

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Roel Schroeven
[EMAIL PROTECTED] schreef: On Sun, 08 Jul 2007 17:37:28 +0200, Roel Schroeven [EMAIL PROTECTED] wrote: 1. open a.jpg 2. save a.jpg - a.jpg is saved with the default quality, 85. Fine by me. 3. save a.jpg with save as, with quality say 55 - as expected it is saved with quality 55. 4.

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Guillermo Espertino
OMG, at last! That's what I was trying to say since the beginning. I know jpeg is a lossy format (I knew that for at least ten years). I know, and always knew, that it has generational degradation. I didn't know that PS compression scale doesn't follow the jpeg specification. Thanks for the

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Sven Neumann
Hi, On Sun, 2007-07-08 at 18:31 -0300, Guillermo Espertino wrote: What I didn't know (and wouldn't expect) is that Gimp will destroy my pictures without warning me. And that's exactly what I get. I have a picture taken at 95, open it and save it, and it ends up at 85. Why is that?

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Sven Neumann
Hi, here's what I suggest that we do (short-term). It should be a simple change and it will avoid that what happened to Guillermo happens to others in the future. The JPEG plug-in should not use the last-used values when being run non-interactively from the Save action. It should use the, now

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread gg
On Sun, 08 Jul 2007 23:48:28 +0200, Sven Neumann [EMAIL PROTECTED] wrote: Hi, On Sun, 2007-07-08 at 18:31 -0300, Guillermo Espertino wrote: What I didn't know (and wouldn't expect) is that Gimp will destroy my pictures without warning me. And that's exactly what I get. I have a picture

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Guillermo Espertino
So please calm down and let the developers deal with this. After all this is a developer list. Your harsh comments are not helpful. I'm not being harsh. At least it wasn't my intention. In fact, this list is commonly considered to be harsh by many people, but now I learn that there's

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Robert L Krawitz
From: Sven Neumann [EMAIL PROTECTED] Date: Sun, 08 Jul 2007 23:48:28 +0200 On Sun, 2007-07-08 at 18:31 -0300, Guillermo Espertino wrote: What I didn't know (and wouldn't expect) is that Gimp will destroy my pictures without warning me. And that's exactly what I get. I have

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Tor Lillqvist
Guillermo Espertino writes: I didn't know that PS compression scale doesn't follow the jpeg specification. There is no such specification for a compression scale or quality factor. Inside an JPEG image, what actually defines the lossiness of the compression are a set of so-called

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Tor Lillqvist
Sven Neumann writes: I already explained that the JPEG plug-in cannot access the settings that were used to save the file. Actually, it shouldn't be that hard to at least try. If the quantization tables used in an image correspond exactly (or closely enough) to those produced by libjpeg with

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Tor Lillqvist
Tor Lillqvist writes: One might imagine some application even doing a clever analysis of an individual image to come up with image-specific quantization tables.

Re: [Gimp-developer] jpeg quality factor.

2007-07-08 Thread Graeme Gill
Tor Lillqvist wrote:One might even consider keeping and re-using the original quantization tables instead of using jpeg_set_quality() in case the quantization tables don't seem to be produced by libjpeg. Which is what I understand Photoshop does, thereby giving users the least level of

Re: [Gimp-developer] jpeg quality factor.

2007-07-07 Thread gg
On Sat, 07 Jul 2007 07:19:57 +0200, Guillermo Espertino [EMAIL PROTECTED] wrote: Se only opened the image from the camera, adjusted the curves, and scaled it down (BTW, the downscale code should do oversamplig by default. It always breaks a little the edges). Until she saved, the image

Re: [Gimp-developer] jpeg quality factor.

2007-07-07 Thread Michael Schumacher
Guillermo Espertino wrote: In Gimp the compression factor is expressed as quality factor. So 100% is the best and 0% is the worst. GIMP does use the IJG quality scale. Well, 70% isn't the same in Gimp and in Photoshop. And it doesn't sound very logical. Blame Adobe for this. The JPEG FAQ

  1   2   >