Re: [PHP] Re: GD Watermark Question-
At 12:21 PM -0400 9/19/10, TR Shaw wrote: On Sep 19, 2010, at 11:45 AM, tedd wrote: At 6:56 PM -0400 9/17/10, TR Shaw wrote: On Sep 17, 2010, at 6:49 PM, Ashley Sheridan wrote: > At the end of the day, if you want to prevent people downloading your images, then just don't show them the image. Actually you can. Serve up an image from the DB and add watermark or whatever on the fly for web browsers. If a user downloads (assuming that s/he bought the image or the image is a "freebie" ) the image comes from the DB directly to the user using download headers. Tom Actually you can't. Regardless of where the image comes from (DB or file), when the user see's the image, they have it. Tedd, You missed what I said: orig file on server -> php that addes watermark when image is required by a browser -> browser accespts and displays image with watermark on it. Similar to you example. Tom Tom: Are you saying that all images shown to the user via a browser will have a watermark on them and if they get permission (i.e., pay for it) then they can have access to a link that will allow them to download the image? Is that what you are saying? If so, then why not say that? Our points have been that browser download images -- period. If you want to protect your images, then you have to come up with a protection scheme other than simply using browsers to view the images. Cheers, tedd -- --- http://sperling.com/ -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Re: GD Watermark Question-
At 12:32 PM -0400 9/19/10, TR Shaw wrote: On Sep 19, 2010, at 11:50 AM, tedd wrote: At 12:36 AM +0100 9/18/10, Ashley Sheridan wrote: I know this is getting a little off-topic here, but surely the way a jpeg destroys data in an image would destroy the stenography information too? To the human eye all would appear normal, but the copyright info would be lost? I don't know much about this sort of thing, so I'm making assumptions here. It's the difference between lossless and lossy compression. The first meaning no loss in data and the second is loss of data. PNG and jpeg is lossless whereas gif is lossy. Actually GIF is lossless (it uses LZW encoding) PNG is also lossless (Ii uses DEFLATE). The specification for JPEG supports both lossy and lossless. And then, of course there is wavelet used in JPEG2000 and other wavelets These are lossy. Tom Aahh... I stand corrected. My statement was from my experience of taking images (i.e., jpeg/png) and then creating GIF's from them where the process was lossy. The process took the entire palette of colors provided by jpeg/png and then picked the "best" 256 colors to create the image, which is no question lossy. However, the data compression technique to create the GIF was not lossy. My bad. Cheers, tedd -- --- http://sperling.com/ -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Re: GD Watermark Question-
On Sep 19, 2010, at 11:50 AM, tedd wrote: > At 12:36 AM +0100 9/18/10, Ashley Sheridan wrote: >> >> I know this is getting a little off-topic here, but surely the way a >> jpeg destroys data in an image would destroy the stenography information >> too? To the human eye all would appear normal, but the copyright info >> would be lost? >> >> I don't know much about this sort of thing, so I'm making assumptions >> here. > > > It's the difference between lossless and lossy compression. The first meaning > no loss in data and the second is loss of data. PNG and jpeg is lossless > whereas gif is lossy. Actually GIF is lossless (it uses LZW encoding) PNG is also lossless (Ii uses DEFLATE). The specification for JPEG supports both lossy and lossless. And then, of course there is wavelet used in JPEG2000 and other wavelets These are lossy. Tom -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Re: GD Watermark Question-
At 7:56 PM -0400 9/17/10, TR Shaw wrote: Nevertheless, I say again the key is to add something is that if an employee of a customer who purchases the image and resells it that you have a possibility to prove. Yes really smart bad people can defeat but 1) most of these aren't stealing your pictures and 2) the others don't know you have embedded a copyright. tom While it won't defeat smart bad people, it will cause them to pause: http://webbytedd.com/b/protect-image/ Cheers, tedd -- --- http://sperling.com/ -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Re: GD Watermark Question-
At 12:36 AM +0100 9/18/10, Ashley Sheridan wrote: I know this is getting a little off-topic here, but surely the way a jpeg destroys data in an image would destroy the stenography information too? To the human eye all would appear normal, but the copyright info would be lost? I don't know much about this sort of thing, so I'm making assumptions here. It's the difference between lossless and lossy compression. The first meaning no loss in data and the second is loss of data. PNG and jpeg is lossless whereas gif is lossy. Cheers, tedd -- --- http://sperling.com/ -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Re: GD Watermark Question-
At 6:56 PM -0400 9/17/10, TR Shaw wrote: On Sep 17, 2010, at 6:49 PM, Ashley Sheridan wrote: > At the end of the day, if you want to prevent people downloading your images, then just don't show them the image. Actually you can. Serve up an image from the DB and add watermark or whatever on the fly for web browsers. If a user downloads (assuming that s/he bought the image or the image is a "freebie" ) the image comes from the DB directly to the user using download headers. Tom Actually you can't. Regardless of where the image comes from (DB or file), when the user see's the image, they have it. Cheers, tedd -- --- http://sperling.com/ -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
[PHP] Re: GD Watermark Question-
At 6:21 PM -0400 9/17/10, Gary wrote: ""Gary"" wrote in message news:1f.27.30333.1d5e3...@pb1.pair.com... Is there a way to insert a watermark on an image as it is being uploaded to the image file, then removed when it is called from a database to be viewed on a website? The rational behind this is I have a photographers site I am doing, and I am limiting the size of the images somewhat to reduce pilferage and I would like to be able to show the images a little larger, hence with a bit more clarity and detail. > Thanks for your input. Gary: When the user see's an image in their browser they *have* downloaded it. You cannot show them an image without a watermark and then somehow prohibit them from downloading the image. When you show it, you've lost control. My advice, show them an image with a watermark and only allow them to see an image without the watermark when you want them to see it -- in other words, protect the image. Cheers, tedd -- --- http://sperling.com/ -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
[PHP] Re: GD Watermark Question
Thank you both for your input, my assumption was when an image file is gathered from a web page, through whatever method, the image was going to be served up from the server, thus if the image file on the server had the watermark, then so would the image that is being captured. Thanks again for your help. Gary ""Gary"" wrote in message news:1f.27.30333.1d5e3...@pb1.pair.com... > Is there a way to insert a watermark on an image as it is being uploaded > to the image file, then removed when it is called from a database to be > viewed on a website? > > The rational behind this is I have a photographers site I am doing, and I > am limiting the size of the images somewhat to reduce pilferage and I > would like to be able to show the images a little larger, hence with a bit > more clarity and detail. > > Thanks for your input. > > Gary > > > __ Information from ESET Smart Security, version of virus > signature database 5458 (20100917) __ > > The message was checked by ESET Smart Security. > > http://www.eset.com > > > > __ Information from ESET Smart Security, version of virus signature database 5458 (20100917) __ The message was checked by ESET Smart Security. http://www.eset.com -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Re: GD Watermark Question-
"Ashley Sheridan" wrote in message news:1284763747.12459.40.ca...@localhost... > On Fri, 2010-09-17 at 18:41 -0400, TR Shaw wrote: > >> Gary >> >> you do realize that if you display the image in a browser without the >> watermark, simple drag and drop can copy the image as is (eg without the >> watermark) >> >> Tom >> >> On Sep 17, 2010, at 6:21 PM, Gary wrote: >> >> > >> > ""Gary"" wrote in message >> > news:1f.27.30333.1d5e3...@pb1.pair.com... >> >> Is there a way to insert a watermark on an image as it is being >> >> uploaded >> >> to the image file, then removed when it is called from a database to >> >> be >> >> viewed on a website? >> >> >> >> The rational behind this is I have a photographers site I am doing, >> >> and I >> >> am limiting the size of the images somewhat to reduce pilferage and I >> >> would like to be able to show the images a little larger, hence with a >> >> bit >> >> more clarity and detail. >> >> >> >> Thanks for your input. >> >> >> >> Gary >> > >> > More info. >> > >> > I was asked off board where the watermark would show, so I am sorry if >> > I was >> > less than clear. The watermark would show on an image that is being >> > downloaded from the server. If this were to work, I could let viewers >> > see >> > an image with a size of 640px in width to show clarity, (they are only >> > able >> > to see an image now with a width of 250 px now) should they decide to >> > help >> > themselves to it, it would download with a watermark on it, but the >> > watermark would not appear on the web page itself. >> > >> > Gary >> > >> > >> > >> > __ Information from ESET Smart Security, version of virus >> > signature database 5458 (20100917) __ >> > >> > The message was checked by ESET Smart Security. >> > >> > http://www.eset.com >> > >> > >> > >> > >> > >> > -- >> > PHP General Mailing List (http://www.php.net/) >> > To unsubscribe, visit: http://www.php.net/unsub.php >> > >> >> > > > There's no way to do this. Anything you see in your browser has already > been downloaded in some form onto your computer, and once that happens > it's out of your control. PHP has no way to detect if the image is being > requested by the browser to view or download, so can't do what you want. > > Besides which, if an image is displayed in the browser, there are dozens > of ways to get at it, from right clicking and saving it, using the media > tab of the file info dialogue (firefox), using firebug to view it, > saving it from the cache, saving the whole page, using wget to spider > and save that page, etc. > > The only way to do what you want is to have your own custom browser app > (possibly written in Java) but even then someone could simply do a print > screen. > > At the end of the day, if you want to prevent people downloading your > images, then just don't show them the image. > > Thanks, > Ash > http://www.ashleysheridan.co.uk > Ashley When I right click on an image, I assumed it is being called from the server, not from the browser, which is why I thought this might work. Thanks for your help. Gary __ Information from ESET Smart Security, version of virus signature database 5458 (20100917) __ The message was checked by ESET Smart Security. http://www.eset.com -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Re: GD Watermark Question-
Tom No, I had never D&D'd an image, however I just did. So I see your point. Thanks for your input. Gary "TR Shaw" wrote in message news:cff72d3b-52cf-4baf-b60f-6b3709c98...@oitc.com... Gary you do realize that if you display the image in a browser without the watermark, simple drag and drop can copy the image as is (eg without the watermark) Tom On Sep 17, 2010, at 6:21 PM, Gary wrote: > > ""Gary"" wrote in message > news:1f.27.30333.1d5e3...@pb1.pair.com... >> Is there a way to insert a watermark on an image as it is being uploaded >> to the image file, then removed when it is called from a database to be >> viewed on a website? >> >> The rational behind this is I have a photographers site I am doing, and I >> am limiting the size of the images somewhat to reduce pilferage and I >> would like to be able to show the images a little larger, hence with a >> bit >> more clarity and detail. >> >> Thanks for your input. >> >> Gary > > More info. > > I was asked off board where the watermark would show, so I am sorry if I > was > less than clear. The watermark would show on an image that is being > downloaded from the server. If this were to work, I could let viewers see > an image with a size of 640px in width to show clarity, (they are only > able > to see an image now with a width of 250 px now) should they decide to help > themselves to it, it would download with a watermark on it, but the > watermark would not appear on the web page itself. > > Gary > > > > __ Information from ESET Smart Security, version of virus > signature database 5458 (20100917) __ > > The message was checked by ESET Smart Security. > > http://www.eset.com > > > > > > -- > PHP General Mailing List (http://www.php.net/) > To unsubscribe, visit: http://www.php.net/unsub.php > __ Information from ESET Smart Security, version of virus signature database 5458 (20100917) __ The message was checked by ESET Smart Security. http://www.eset.com __ Information from ESET Smart Security, version of virus signature database 5458 (20100917) __ The message was checked by ESET Smart Security. http://www.eset.com -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Re: GD Watermark Question-
On Sep 17, 2010, at 7:36 PM, Ashley Sheridan wrote: > > >>> >>> Even the stenography has its flaws. Opening the image in an image editor, >>> then doing a select all and pasting as a new image would remove any hidden >>> meta info, and saving a couple of times as a jpeg would destroy any >>> detailed information without distorting the photo (assuming it was a photo >>> and not a diagram which would look awful as a jpeg) >>> >>> I'm not sure if you ever had this at your school, but back when I was a >>> kid, once a year class photos would be taken, as well as photos by >>> yourself, even if you didn't want them. To ensure people paid for the >>> proper photo, a large watermark was sprawled across the photo. It took a >>> little while, but with a decent image editor you could pull out that >>> watermark from the scanned in photo and have a good quality photo without >>> paying for it. I'm not saying we should all do this (the photographer needs >>> to be paid somehow!) but I'm saying it's possible if you have the time, >>> inclination and means. >>> >> >> Actually Ash, properly done stenography is actually embedded it the pixels - >> not the metadata and can be placed such that only when the image is reduced >> to x degraded percent is it lost which removes the value of the full res >> image. >> >> However, the power of real stenography for copyrights (and not for spying) >> is about the fact that the real user uses the image and if it gets copies by >> someone the stenography copyright signatures remain and the copier doesn't >> know about them >> >> Tom >> >> > > > I know this is getting a little off-topic here, but surely the way a > jpeg destroys data in an image would destroy the stenography information > too? To the human eye all would appear normal, but the copyright info > would be lost? > > I don't know much about this sort of thing, so I'm making assumptions > here. > Totally depends on the approach. Both jpeg and jpeg 2000 have their own mathematical characteristics which can be properly exploited. Nevertheless, I say again the key is to add something is that if an employee of a customer who purchases the image and resells it that you have a possibility to prove. Yes really smart bad people can defeat but 1) most of these aren't stealing your pictures and 2) the others don't know you have embedded a copyright. tom Tom -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Re: GD Watermark Question-
> > > > Even the stenography has its flaws. Opening the image in an image editor, > > then doing a select all and pasting as a new image would remove any hidden > > meta info, and saving a couple of times as a jpeg would destroy any > > detailed information without distorting the photo (assuming it was a photo > > and not a diagram which would look awful as a jpeg) > > > > I'm not sure if you ever had this at your school, but back when I was a > > kid, once a year class photos would be taken, as well as photos by > > yourself, even if you didn't want them. To ensure people paid for the > > proper photo, a large watermark was sprawled across the photo. It took a > > little while, but with a decent image editor you could pull out that > > watermark from the scanned in photo and have a good quality photo without > > paying for it. I'm not saying we should all do this (the photographer needs > > to be paid somehow!) but I'm saying it's possible if you have the time, > > inclination and means. > > > > Actually Ash, properly done stenography is actually embedded it the pixels - > not the metadata and can be placed such that only when the image is reduced > to x degraded percent is it lost which removes the value of the full res > image. > > However, the power of real stenography for copyrights (and not for spying) is > about the fact that the real user uses the image and if it gets copies by > someone the stenography copyright signatures remain and the copier doesn't > know about them > > Tom > > I know this is getting a little off-topic here, but surely the way a jpeg destroys data in an image would destroy the stenography information too? To the human eye all would appear normal, but the copyright info would be lost? I don't know much about this sort of thing, so I'm making assumptions here. Thanks, Ash http://www.ashleysheridan.co.uk
Re: [PHP] Re: GD Watermark Question-
On Sep 17, 2010, at 7:25 PM, Ashley Sheridan wrote: > On Fri, 2010-09-17 at 19:20 -0400, TR Shaw wrote: >> >> On Sep 17, 2010, at 6:58 PM, Ashley Sheridan wrote: >> >>> On Fri, 2010-09-17 at 18:56 -0400, TR Shaw wrote: On Sep 17, 2010, at 6:49 PM, Ashley Sheridan wrote: > On Fri, 2010-09-17 at 18:41 -0400, TR Shaw wrote: > >> Gary >> >> you do realize that if you display the image in a browser without the >> watermark, simple drag and drop can copy the image as is (eg without >> the watermark) >> >> Tom >> >> On Sep 17, 2010, at 6:21 PM, Gary wrote: >> >>> >>> ""Gary"" wrote in message >>> news:1f.27.30333.1d5e3...@pb1.pair.com... Is there a way to insert a watermark on an image as it is being uploaded to the image file, then removed when it is called from a database to be viewed on a website? The rational behind this is I have a photographers site I am doing, and I am limiting the size of the images somewhat to reduce pilferage and I would like to be able to show the images a little larger, hence with a bit more clarity and detail. Thanks for your input. Gary >>> >>> More info. >>> >>> I was asked off board where the watermark would show, so I am sorry if >>> I was >>> less than clear. The watermark would show on an image that is being >>> downloaded from the server. If this were to work, I could let viewers >>> see >>> an image with a size of 640px in width to show clarity, (they are >>> only able >>> to see an image now with a width of 250 px now) should they decide to >>> help >>> themselves to it, it would download with a watermark on it, but the >>> watermark would not appear on the web page itself. >>> >>> Gary >>> >>> >>> >>> __ Information from ESET Smart Security, version of virus >>> signature database 5458 (20100917) __ >>> >>> The message was checked by ESET Smart Security. >>> >>> http://www.eset.com >>> >>> >>> >>> >>> >>> -- >>> PHP General Mailing List (http://www.php.net/) >>> To unsubscribe, visit: http://www.php.net/unsub.php >>> >> >> > > > There's no way to do this. Anything you see in your browser has already > been downloaded in some form onto your computer, and once that happens > it's out of your control. PHP has no way to detect if the image is being > requested by the browser to view or download, so can't do what you want. > > Besides which, if an image is displayed in the browser, there are dozens > of ways to get at it, from right clicking and saving it, using the media > tab of the file info dialogue (firefox), using firebug to view it, > saving it from the cache, saving the whole page, using wget to spider > and save that page, etc. > > The only way to do what you want is to have your own custom browser app > (possibly written in Java) but even then someone could simply do a print > screen. > > At the end of the day, if you want to prevent people downloading your > images, then just don't show them the image. Actually you can. Serve up an image from the DB and add watermark or whatever on the fly for web browsers. If a user downloads (assuming that s/he bought the image or the image is a "freebie" ) the image comes from the DB directly to the user using download headers. Tom >>> >>> But the downloading will still be happening through the web browser, which >>> PHP won't be able to recognise. >>> >> >> >> True but the key is that you only download IF the person has paid - lets >> face it once someone has paid and accessed the image all bets are off as for >> control. >> >> >> Now, for those paid for files he could implement steganography to hide his >> watermark/copyright in the image for later legal action if required. >> >> >> Tom >> >> > > Even the stenography has its flaws. Opening the image in an image editor, > then doing a select all and pasting as a new image would remove any hidden > meta info, and saving a couple of times as a jpeg would destroy any detailed > information without distorting the photo (assuming it was a photo and not a > diagram which would look awful as a jpeg) > > I'm not sure if you ever had this at your school, but back when I was a kid, > once a year class photos would be taken, as well as photos by yourself, even > if you didn't want them. To ensure people paid for the proper photo, a large > watermark was sprawled across the photo. It took a little while, but with a > decent imag
Re: [PHP] Re: GD Watermark Question-
On Fri, 2010-09-17 at 19:20 -0400, TR Shaw wrote: > > > On Sep 17, 2010, at 6:58 PM, Ashley Sheridan wrote: > > > > > On Fri, 2010-09-17 at 18:56 -0400, TR Shaw wrote: > > > > > On Sep 17, 2010, at 6:49 PM, Ashley Sheridan wrote: > > > > > > > On Fri, 2010-09-17 at 18:41 -0400, TR Shaw wrote: > > > > > > > >> Gary > > > >> > > > >> you do realize that if you display the image in a browser without the > > > >> watermark, simple drag and drop can copy the image as is (eg without > > > >> the watermark) > > > >> > > > >> Tom > > > >> > > > >> On Sep 17, 2010, at 6:21 PM, Gary wrote: > > > >> > > > >>> > > > >>> ""Gary"" wrote in message > > > >>> news:1f.27.30333.1d5e3...@pb1.pair.com... > > > Is there a way to insert a watermark on an image as it is being > > > uploaded > > > to the image file, then removed when it is called from a database to > > > be > > > viewed on a website? > > > > > > The rational behind this is I have a photographers site I am doing, > > > and I > > > am limiting the size of the images somewhat to reduce pilferage and > > > I > > > would like to be able to show the images a little larger, hence with > > > a bit > > > more clarity and detail. > > > > > > Thanks for your input. > > > > > > Gary > > > >>> > > > >>> More info. > > > >>> > > > >>> I was asked off board where the watermark would show, so I am sorry > > > >>> if I was > > > >>> less than clear. The watermark would show on an image that is being > > > >>> downloaded from the server. If this were to work, I could let > > > >>> viewers see > > > >>> an image with a size of 640px in width to show clarity, (they are > > > >>> only able > > > >>> to see an image now with a width of 250 px now) should they decide to > > > >>> help > > > >>> themselves to it, it would download with a watermark on it, but the > > > >>> watermark would not appear on the web page itself. > > > >>> > > > >>> Gary > > > >>> > > > >>> > > > >>> > > > >>> __ Information from ESET Smart Security, version of virus > > > >>> signature database 5458 (20100917) __ > > > >>> > > > >>> The message was checked by ESET Smart Security. > > > >>> > > > >>> http://www.eset.com > > > >>> > > > >>> > > > >>> > > > >>> > > > >>> > > > >>> -- > > > >>> PHP General Mailing List (http://www.php.net/) > > > >>> To unsubscribe, visit: http://www.php.net/unsub.php > > > >>> > > > >> > > > >> > > > > > > > > > > > > There's no way to do this. Anything you see in your browser has already > > > > been downloaded in some form onto your computer, and once that happens > > > > it's out of your control. PHP has no way to detect if the image is being > > > > requested by the browser to view or download, so can't do what you want. > > > > > > > > Besides which, if an image is displayed in the browser, there are dozens > > > > of ways to get at it, from right clicking and saving it, using the media > > > > tab of the file info dialogue (firefox), using firebug to view it, > > > > saving it from the cache, saving the whole page, using wget to spider > > > > and save that page, etc. > > > > > > > > The only way to do what you want is to have your own custom browser app > > > > (possibly written in Java) but even then someone could simply do a print > > > > screen. > > > > > > > > At the end of the day, if you want to prevent people downloading your > > > > images, then just don't show them the image. > > > > > > Actually you can. Serve up an image from the DB and add watermark or > > > whatever on the fly for web browsers. If a user downloads (assuming that > > > s/he bought the image or the image is a "freebie" ) the image comes from > > > the DB directly to the user using download headers. > > > > > > Tom > > > > > > > > > But the downloading will still be happening through the web browser, > > which PHP won't be able to recognise. > > > > > > True but the key is that you only download IF the person has paid - > lets face it once someone has paid and accessed the image all bets are > off as for control. > > > > Now, for those paid for files he could implement steganography to hide > his watermark/copyright in the image for later legal action if > required. > > > Tom > > Even the stenography has its flaws. Opening the image in an image editor, then doing a select all and pasting as a new image would remove any hidden meta info, and saving a couple of times as a jpeg would destroy any detailed information without distorting the photo (assuming it was a photo and not a diagram which would look awful as a jpeg) I'm not sure if you ever had this at your school, but back when I was a kid, once a year class photos would be taken, as well as photos by yourself, even if you didn't want them. To ensure people paid for the proper photo, a large watermark was sprawled across the photo. It took a little while,
Re: [PHP] Re: GD Watermark Question-
On Sep 17, 2010, at 6:58 PM, Ashley Sheridan wrote: > On Fri, 2010-09-17 at 18:56 -0400, TR Shaw wrote: >> >> On Sep 17, 2010, at 6:49 PM, Ashley Sheridan wrote: >> >> > On Fri, 2010-09-17 at 18:41 -0400, TR Shaw wrote: >> > >> >> Gary >> >> >> >> you do realize that if you display the image in a browser without the >> >> watermark, simple drag and drop can copy the image as is (eg without the >> >> watermark) >> >> >> >> Tom >> >> >> >> On Sep 17, 2010, at 6:21 PM, Gary wrote: >> >> >> >>> >> >>> ""Gary"" wrote in message >> >>> news:1f.27.30333.1d5e3...@pb1.pair.com... >> Is there a way to insert a watermark on an image as it is being >> uploaded >> to the image file, then removed when it is called from a database to be >> viewed on a website? >> >> The rational behind this is I have a photographers site I am doing, and >> I >> am limiting the size of the images somewhat to reduce pilferage and I >> would like to be able to show the images a little larger, hence with a >> bit >> more clarity and detail. >> >> Thanks for your input. >> >> Gary >> >>> >> >>> More info. >> >>> >> >>> I was asked off board where the watermark would show, so I am sorry if I >> >>> was >> >>> less than clear. The watermark would show on an image that is being >> >>> downloaded from the server. If this were to work, I could let viewers >> >>> see >> >>> an image with a size of 640px in width to show clarity, (they are only >> >>> able >> >>> to see an image now with a width of 250 px now) should they decide to >> >>> help >> >>> themselves to it, it would download with a watermark on it, but the >> >>> watermark would not appear on the web page itself. >> >>> >> >>> Gary >> >>> >> >>> >> >>> >> >>> __ Information from ESET Smart Security, version of virus >> >>> signature database 5458 (20100917) __ >> >>> >> >>> The message was checked by ESET Smart Security. >> >>> >> >>> http://www.eset.com >> >>> >> >>> >> >>> >> >>> >> >>> >> >>> -- >> >>> PHP General Mailing List (http://www.php.net/) >> >>> To unsubscribe, visit: http://www.php.net/unsub.php >> >>> >> >> >> >> >> > >> > >> > There's no way to do this. Anything you see in your browser has already >> > been downloaded in some form onto your computer, and once that happens >> > it's out of your control. PHP has no way to detect if the image is being >> > requested by the browser to view or download, so can't do what you want. >> > >> > Besides which, if an image is displayed in the browser, there are dozens >> > of ways to get at it, from right clicking and saving it, using the media >> > tab of the file info dialogue (firefox), using firebug to view it, >> > saving it from the cache, saving the whole page, using wget to spider >> > and save that page, etc. >> > >> > The only way to do what you want is to have your own custom browser app >> > (possibly written in Java) but even then someone could simply do a print >> > screen. >> > >> > At the end of the day, if you want to prevent people downloading your >> > images, then just don't show them the image. >> >> Actually you can. Serve up an image from the DB and add watermark or >> whatever on the fly for web browsers. If a user downloads (assuming that >> s/he bought the image or the image is a "freebie" ) the image comes from the >> DB directly to the user using download headers. >> >> Tom >> > > But the downloading will still be happening through the web browser, which > PHP won't be able to recognise. True but the key is that you only download IF the person has paid - lets face it once someone has paid and accessed the image all bets are off as for control. Now, for those paid for files he could implement steganography to hide his watermark/copyright in the image for later legal action if required. Tom
Re: [PHP] Re: GD Watermark Question-
On Fri, 2010-09-17 at 18:56 -0400, TR Shaw wrote: > On Sep 17, 2010, at 6:49 PM, Ashley Sheridan wrote: > > > On Fri, 2010-09-17 at 18:41 -0400, TR Shaw wrote: > > > >> Gary > >> > >> you do realize that if you display the image in a browser without the > >> watermark, simple drag and drop can copy the image as is (eg without the > >> watermark) > >> > >> Tom > >> > >> On Sep 17, 2010, at 6:21 PM, Gary wrote: > >> > >>> > >>> ""Gary"" wrote in message > >>> news:1f.27.30333.1d5e3...@pb1.pair.com... > Is there a way to insert a watermark on an image as it is being uploaded > to the image file, then removed when it is called from a database to be > viewed on a website? > > The rational behind this is I have a photographers site I am doing, and > I > am limiting the size of the images somewhat to reduce pilferage and I > would like to be able to show the images a little larger, hence with a > bit > more clarity and detail. > > Thanks for your input. > > Gary > >>> > >>> More info. > >>> > >>> I was asked off board where the watermark would show, so I am sorry if I > >>> was > >>> less than clear. The watermark would show on an image that is being > >>> downloaded from the server. If this were to work, I could let viewers > >>> see > >>> an image with a size of 640px in width to show clarity, (they are only > >>> able > >>> to see an image now with a width of 250 px now) should they decide to > >>> help > >>> themselves to it, it would download with a watermark on it, but the > >>> watermark would not appear on the web page itself. > >>> > >>> Gary > >>> > >>> > >>> > >>> __ Information from ESET Smart Security, version of virus > >>> signature database 5458 (20100917) __ > >>> > >>> The message was checked by ESET Smart Security. > >>> > >>> http://www.eset.com > >>> > >>> > >>> > >>> > >>> > >>> -- > >>> PHP General Mailing List (http://www.php.net/) > >>> To unsubscribe, visit: http://www.php.net/unsub.php > >>> > >> > >> > > > > > > There's no way to do this. Anything you see in your browser has already > > been downloaded in some form onto your computer, and once that happens > > it's out of your control. PHP has no way to detect if the image is being > > requested by the browser to view or download, so can't do what you want. > > > > Besides which, if an image is displayed in the browser, there are dozens > > of ways to get at it, from right clicking and saving it, using the media > > tab of the file info dialogue (firefox), using firebug to view it, > > saving it from the cache, saving the whole page, using wget to spider > > and save that page, etc. > > > > The only way to do what you want is to have your own custom browser app > > (possibly written in Java) but even then someone could simply do a print > > screen. > > > > At the end of the day, if you want to prevent people downloading your > > images, then just don't show them the image. > > Actually you can. Serve up an image from the DB and add watermark or > whatever on the fly for web browsers. If a user downloads (assuming that s/he > bought the image or the image is a "freebie" ) the image comes from the DB > directly to the user using download headers. > > Tom > But the downloading will still be happening through the web browser, which PHP won't be able to recognise. Thanks, Ash http://www.ashleysheridan.co.uk
Re: [PHP] Re: GD Watermark Question-
On Sep 17, 2010, at 6:49 PM, Ashley Sheridan wrote: > On Fri, 2010-09-17 at 18:41 -0400, TR Shaw wrote: > >> Gary >> >> you do realize that if you display the image in a browser without the >> watermark, simple drag and drop can copy the image as is (eg without the >> watermark) >> >> Tom >> >> On Sep 17, 2010, at 6:21 PM, Gary wrote: >> >>> >>> ""Gary"" wrote in message >>> news:1f.27.30333.1d5e3...@pb1.pair.com... Is there a way to insert a watermark on an image as it is being uploaded to the image file, then removed when it is called from a database to be viewed on a website? The rational behind this is I have a photographers site I am doing, and I am limiting the size of the images somewhat to reduce pilferage and I would like to be able to show the images a little larger, hence with a bit more clarity and detail. Thanks for your input. Gary >>> >>> More info. >>> >>> I was asked off board where the watermark would show, so I am sorry if I >>> was >>> less than clear. The watermark would show on an image that is being >>> downloaded from the server. If this were to work, I could let viewers see >>> an image with a size of 640px in width to show clarity, (they are only >>> able >>> to see an image now with a width of 250 px now) should they decide to help >>> themselves to it, it would download with a watermark on it, but the >>> watermark would not appear on the web page itself. >>> >>> Gary >>> >>> >>> >>> __ Information from ESET Smart Security, version of virus signature >>> database 5458 (20100917) __ >>> >>> The message was checked by ESET Smart Security. >>> >>> http://www.eset.com >>> >>> >>> >>> >>> >>> -- >>> PHP General Mailing List (http://www.php.net/) >>> To unsubscribe, visit: http://www.php.net/unsub.php >>> >> >> > > > There's no way to do this. Anything you see in your browser has already > been downloaded in some form onto your computer, and once that happens > it's out of your control. PHP has no way to detect if the image is being > requested by the browser to view or download, so can't do what you want. > > Besides which, if an image is displayed in the browser, there are dozens > of ways to get at it, from right clicking and saving it, using the media > tab of the file info dialogue (firefox), using firebug to view it, > saving it from the cache, saving the whole page, using wget to spider > and save that page, etc. > > The only way to do what you want is to have your own custom browser app > (possibly written in Java) but even then someone could simply do a print > screen. > > At the end of the day, if you want to prevent people downloading your > images, then just don't show them the image. Actually you can. Serve up an image from the DB and add watermark or whatever on the fly for web browsers. If a user downloads (assuming that s/he bought the image or the image is a "freebie" ) the image comes from the DB directly to the user using download headers. Tom -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Re: GD Watermark Question-
On Fri, 2010-09-17 at 18:41 -0400, TR Shaw wrote: > Gary > > you do realize that if you display the image in a browser without the > watermark, simple drag and drop can copy the image as is (eg without the > watermark) > > Tom > > On Sep 17, 2010, at 6:21 PM, Gary wrote: > > > > > ""Gary"" wrote in message > > news:1f.27.30333.1d5e3...@pb1.pair.com... > >> Is there a way to insert a watermark on an image as it is being uploaded > >> to the image file, then removed when it is called from a database to be > >> viewed on a website? > >> > >> The rational behind this is I have a photographers site I am doing, and I > >> am limiting the size of the images somewhat to reduce pilferage and I > >> would like to be able to show the images a little larger, hence with a bit > >> more clarity and detail. > >> > >> Thanks for your input. > >> > >> Gary > > > > More info. > > > > I was asked off board where the watermark would show, so I am sorry if I > > was > > less than clear. The watermark would show on an image that is being > > downloaded from the server. If this were to work, I could let viewers see > > an image with a size of 640px in width to show clarity, (they are only > > able > > to see an image now with a width of 250 px now) should they decide to help > > themselves to it, it would download with a watermark on it, but the > > watermark would not appear on the web page itself. > > > > Gary > > > > > > > > __ Information from ESET Smart Security, version of virus signature > > database 5458 (20100917) __ > > > > The message was checked by ESET Smart Security. > > > > http://www.eset.com > > > > > > > > > > > > -- > > PHP General Mailing List (http://www.php.net/) > > To unsubscribe, visit: http://www.php.net/unsub.php > > > > There's no way to do this. Anything you see in your browser has already been downloaded in some form onto your computer, and once that happens it's out of your control. PHP has no way to detect if the image is being requested by the browser to view or download, so can't do what you want. Besides which, if an image is displayed in the browser, there are dozens of ways to get at it, from right clicking and saving it, using the media tab of the file info dialogue (firefox), using firebug to view it, saving it from the cache, saving the whole page, using wget to spider and save that page, etc. The only way to do what you want is to have your own custom browser app (possibly written in Java) but even then someone could simply do a print screen. At the end of the day, if you want to prevent people downloading your images, then just don't show them the image. Thanks, Ash http://www.ashleysheridan.co.uk
Re: [PHP] Re: GD Watermark Question-
Gary you do realize that if you display the image in a browser without the watermark, simple drag and drop can copy the image as is (eg without the watermark) Tom On Sep 17, 2010, at 6:21 PM, Gary wrote: > > ""Gary"" wrote in message > news:1f.27.30333.1d5e3...@pb1.pair.com... >> Is there a way to insert a watermark on an image as it is being uploaded >> to the image file, then removed when it is called from a database to be >> viewed on a website? >> >> The rational behind this is I have a photographers site I am doing, and I >> am limiting the size of the images somewhat to reduce pilferage and I >> would like to be able to show the images a little larger, hence with a bit >> more clarity and detail. >> >> Thanks for your input. >> >> Gary > > More info. > > I was asked off board where the watermark would show, so I am sorry if I was > less than clear. The watermark would show on an image that is being > downloaded from the server. If this were to work, I could let viewers see > an image with a size of 640px in width to show clarity, (they are only able > to see an image now with a width of 250 px now) should they decide to help > themselves to it, it would download with a watermark on it, but the > watermark would not appear on the web page itself. > > Gary > > > > __ Information from ESET Smart Security, version of virus signature > database 5458 (20100917) __ > > The message was checked by ESET Smart Security. > > http://www.eset.com > > > > > > -- > PHP General Mailing List (http://www.php.net/) > To unsubscribe, visit: http://www.php.net/unsub.php > -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
[PHP] Re: GD Watermark Question-
""Gary"" wrote in message news:1f.27.30333.1d5e3...@pb1.pair.com... > Is there a way to insert a watermark on an image as it is being uploaded > to the image file, then removed when it is called from a database to be > viewed on a website? > > The rational behind this is I have a photographers site I am doing, and I > am limiting the size of the images somewhat to reduce pilferage and I > would like to be able to show the images a little larger, hence with a bit > more clarity and detail. > > Thanks for your input. > > Gary More info. I was asked off board where the watermark would show, so I am sorry if I was less than clear. The watermark would show on an image that is being downloaded from the server. If this were to work, I could let viewers see an image with a size of 640px in width to show clarity, (they are only able to see an image now with a width of 250 px now) should they decide to help themselves to it, it would download with a watermark on it, but the watermark would not appear on the web page itself. Gary __ Information from ESET Smart Security, version of virus signature database 5458 (20100917) __ The message was checked by ESET Smart Security. http://www.eset.com -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
