|
thumbnail sizes
I've been using this to make thumbnails of jpeg files:
for img in *.JPG; do echo thumbnailing $img convert -geometry 105x70 $img $img done Files from the K10D result in thumbnails of about 57 kB and those from the GR of about 46 kB, with little variation. Is there a simple explanation as to why? The K10D is 10 megapixels and the GR 16, but I don't see why that is relevant here, but maybe I am missing something. |
thumbnail sizes
"Phillip Helbig (undress to reply)" wrote
| I've been using this to make thumbnails of jpeg files: | | for img in *.JPG; do | echo thumbnailing $img | convert -geometry 105x70 $img $img | done | Are people supposed to know what OS/software you're using that code with? I wonder why you don't just extract the thumbnails when possible. Don't your cameras create them in the JPGs? It should be quicker and yield better quality images. |
thumbnail sizes
On 2018-01-07 21:46, Mayayana wrote:
"Phillip Helbig (undress to reply)" wrote | I've been using this to make thumbnails of jpeg files: | | for img in *.JPG; do | echo thumbnailing $img | convert -geometry 105x70 $img $img | done | Are people supposed to know what OS/software you're using that code with? Linux/bash and ImageMagick, obviously :-P I wonder why you don't just extract the thumbnails when possible. Don't your cameras create them in the JPGs? It should be quicker and yield better quality images. To customize the size and quality, for instance. -- Cheers, Carlos. |
thumbnail sizes
On 2018-01-07 21:07, Phillip Helbig (undress to reply) wrote:
I've been using this to make thumbnails of jpeg files: for img in *.JPG; do echo thumbnailing $img convert -geometry 105x70 $img $img done Files from the K10D result in thumbnails of about 57 kB and those from the GR of about 46 kB, with little variation. Is there a simple explanation as to why? The K10D is 10 megapixels and the GR 16, but I don't see why that is relevant here, but maybe I am missing something. I was going to say that the camera with more megapixels would convert to a bigger size, but the reverse is happening. -- Cheers, Carlos. |
thumbnail sizes
On Jan 7, 2018, Phillip Helbig (undress to reply wrote
(in article ): I've been using this to make thumbnails of jpeg files: for img in *.JPG; do echo thumbnailing $img convert -geometry 105x70 $img $img done Why? Why not use decent software? Files from the K10D result in thumbnails of about 57 kB and those from the GR of about 46 kB, with little variation. Is there a simple explanation as to why? Different cameras, different image content. The K10D is 10 megapixels and the GR 16, but I don't see why that is relevant here, but maybe I am missing something. The RAW file size, and native JPEG size is going to be different for those two cameras. As a result any thumbnail from those different sources is going to have a different size. I am still curious as to why you need to generate thumbnails. It seems to be a pointless exercise. -- Regards, Savageduck |
thumbnail sizes
On Jan 7, 2018, Carlos E.R. wrote
(in article ): On 2018-01-07 21:46, Mayayana wrote: "Phillip Helbig (undress to wrote I've been using this to make thumbnails of jpeg files: for img in *.JPG; do echo thumbnailing $img convert -geometry 105x70 $img $img done Are people supposed to know what OS/software you're using that code with? Linux/bash and ImageMagick, obviously :-P That figures. I wonder why you don't just extract the thumbnails when possible. Don't your cameras create them in the JPGs? It should be quicker and yield better quality images. To customize the size and quality, for instance. Quality for thumbnails? To what purpose? It seems to be a waste of time, and a futile, unnecessary exercise. -- Regards, Savageduck |
thumbnail sizes
"Carlos E.R." wrote
| I was going to say that the camera with more megapixels would convert to | a bigger size, but the reverse is happening. | MP doesn't matter because it's the same number of pixels in the thumbnail if they're both the same width/height. There could be slight differences due to simpler or more complex images that compress differently, but with such a big difference the only explanation I can think of is that there's a difference in the compression. The code doesn't include a "quality" parameter to set compression level so maybe ImageMagick is deciding based on input size? Who knows? He's using a hammer to hit a tack. It's hard to see why it should matter. He's using a limited command line tool to get thumbnails and not even setting the quality option. Does he really need exactly that size? If so, why? Is it worth sacrificing quality? He didn't explain any of that. Apparently he doesn't care very much about the quality but is just curious about the different file sizes resulting. |
thumbnail sizes
"Phillip Helbig (undress to reply)" wrote
| I've been using this to make thumbnails of jpeg files: | | for img in *.JPG; do | echo thumbnailing $img | convert -geometry 105x70 $img $img | done | | Files from the K10D result in thumbnails of about 57 kB and those from | the GR of about 46 kB, with little variation. Is there a simple | explanation as to why? | | The K10D is 10 megapixels and the GR 16, but I don't see why that is | relevant here, but maybe I am missing something. | Are the originals the same aspect ratio? If not then you might be getting something like a 105x65 and a 105x50. You also didn't spec the compression level with the quality parameter. (Assuming you're using ImageMagick as Carlos speculated.) You didn't say what the context of the code is. You didn't say why you're making thumbnails or whether they need to be the same size. You didn't extract them, which would probably make more sense. So all we know is that you're making thumbnails with a poorly suited tool and you don't much care about the quality of them. But you do care about the file size? Why? It'd be easier for people to provide a helpful answer if you'd explain yourself. We're not your mother. |
thumbnail sizes
On 2018-01-07 22:26, Savageduck wrote:
On Jan 7, 2018, Carlos E.R. wrote (in article ): On 2018-01-07 21:46, Mayayana wrote: "Phillip Helbig (undress to wrote I've been using this to make thumbnails of jpeg files: for img in *.JPG; do echo thumbnailing $img convert -geometry 105x70 $img $img done Are people supposed to know what OS/software you're using that code with? Linux/bash and ImageMagick, obviously :-P That figures. I wonder why you don't just extract the thumbnails when possible. Don't your cameras create them in the JPGs? It should be quicker and yield better quality images. To customize the size and quality, for instance. Quality for thumbnails? To what purpose? It seems to be a waste of time, and a futile, unnecessary exercise. No. I said "to customize the size and quality" which is different than doing a quality thumbnail. ie, to have thumbnails of the exact quality (small quality) that one wishes. -- Cheers, Carlos. |
thumbnail sizes
On 2018-01-07 22:22, Savageduck wrote:
On Jan 7, 2018, Phillip Helbig (undress to reply wrote (in article ): I've been using this to make thumbnails of jpeg files: for img in *.JPG; do echo thumbnailing $img convert -geometry 105x70 $img $img done Why? Why not use decent software? "convert" is very decent and powerful software. What would you use in a script, then? -- Cheers, Carlos. |
thumbnail sizes
On 2018-01-07 23:30, Mayayana wrote:
"Phillip Helbig (undress to reply)" wrote | I've been using this to make thumbnails of jpeg files: | | for img in *.JPG; do | echo thumbnailing $img | convert -geometry 105x70 $img $img | done | | Files from the K10D result in thumbnails of about 57 kB and those from | the GR of about 46 kB, with little variation. Is there a simple | explanation as to why? | | The K10D is 10 megapixels and the GR 16, but I don't see why that is | relevant here, but maybe I am missing something. | Are the originals the same aspect ratio? If not then you might be getting something like a 105x65 and a 105x50. You also didn't spec the compression level with the quality parameter. (Assuming you're using ImageMagick as Carlos speculated.) Oh, I'm more than 95% certain :-) You didn't say what the context of the code is. You didn't say why you're making thumbnails or whether they need to be the same size. I rather suppose he is curious about why they are not about the same size, if the pixel number is the same. But it does not matter to me why is he making them. Not my business :-) You didn't extract them, which would probably make more sense. So all we know is that you're making thumbnails with a poorly suited tool and you don't It is a perfectly suited tool for this task (a repeated task in a script). much care about the quality of them. But you do care about the file size? Why? Then use the -quality parameter, to make sure it is the same on all runs. With no value given, the program tries to estimate the value used in the original and use the same (see http://www.imagemagick.org/script/co...s.php#quality). It'd be easier for people to provide a helpful answer if you'd explain yourself. We're not your mother. Sigh... Maybe he doesn't know what other information to provide, and you can simply politely ask for what you think you need :-) -- Cheers, Carlos. |
thumbnail sizes
On Jan 7, 2018, Carlos E.R. wrote
(in article ): On 2018-01-07 22:26, Savageduck wrote: On Jan 7, 2018, Carlos E.R. wrote (in article ): On 2018-01-07 21:46, Mayayana wrote: "Phillip Helbig (undress to wrote I've been using this to make thumbnails of jpeg files: for img in *.JPG; do echo thumbnailing $img convert -geometry 105x70 $img $img done Are people supposed to know what OS/software you're using that code with? Linux/bash and ImageMagick, obviously :-P That figures. I wonder why you don't just extract the thumbnails when possible. Don't your cameras create them in the JPGs? It should be quicker and yield better quality images. To customize the size and quality, for instance. Quality for thumbnails? To what purpose? It seems to be a waste of time, and a futile, unnecessary exercise. No. I said "to customize the size and quality" which is different than doing a quality thumbnail. ie, to have thumbnails of the exact quality (small quality) that one wishes. I am still baffled as why these thumbnails have to be produced in the first place. A proof/contact sheet, some sort of project, what? If there is some odd reason to produce them, which has yet to be explained, why would the concept of “quality” be attached to thumbnails of all things? I have been doing this digital photography thing for some time, and I have yet to have the need to produce a thumbnail of any quality. -- Regards, Savageduck |
thumbnail sizes
On Jan 7, 2018, Carlos E.R. wrote
(in article ): On 2018-01-07 22:22, Savageduck wrote: On Jan 7, 2018, Phillip Helbig (undress to reply wrote (in article ): I've been using this to make thumbnails of jpeg files: for img in *.JPG; do echo thumbnailing $img convert -geometry 105x70 $img $img done Why? Why not use decent software? "convert" is very decent and powerful software. What would you use in a script, then? Why use “convert” which I have never heard of when I have Lightroom, Bridge, and a few others in my photgraphic tool box? -- Regards, Savageduck |
thumbnail sizes
On 2018-01-08 03:14, Savageduck wrote:
On Jan 7, 2018, Carlos E.R. wrote (in article ): I wonder why you don't just extract the thumbnails when possible. Don't your cameras create them in the JPGs? It should be quicker and yield better quality images. To customize the size and quality, for instance. Quality for thumbnails? To what purpose? It seems to be a waste of time, and a futile, unnecessary exercise. No. I said "to customize the size and quality" which is different than doing a quality thumbnail. ie, to have thumbnails of the exact quality (small quality) that one wishes. I am still baffled as why these thumbnails have to be produced in the first place. A proof/contact sheet, some sort of project, what? Does it matter? If there is some odd reason to produce them, which has yet to be explained, why would the concept of “quality” be attached to thumbnails of all things? I have been doing this digital photography thing for some time, and I have yet to have the need to produce a thumbnail of any quality. Yes, you do. Any JPG generation has a "quality". It can be "one", so very bad, or it can be "a hundred", so as best as can be, or any number in between. Any jpg generated or changed has a quality number. You choose the number, or you let the software decide. Having a quality does not mean having high quality. -- Cheers, Carlos. |
thumbnail sizes
In article , Mayayana
wrote: | I've been using this to make thumbnails of jpeg files: | | for img in *.JPG; do | echo thumbnailing $img | convert -geometry 105x70 $img $img | done | Are people supposed to know what OS/software you're using that code with? yes I wonder why you don't just extract the thumbnails when possible. Don't your cameras create them in the JPGs? It should be quicker and yield better quality images. maybe he wants a different size. |
thumbnail sizes
In article , Carlos E.R.
wrote: I am still baffled as why these thumbnails have to be produced in the first place. A proof/contact sheet, some sort of project, what? Does it matter? yes. If there is some odd reason to produce them, which has yet to be explained, why would the concept of quality be attached to thumbnails of all things? I have been doing this digital photography thing for some time, and I have yet to have the need to produce a thumbnail of any quality. Yes, you do. Any JPG generation has a "quality". It can be "one", so very bad, or it can be "a hundred", so as best as can be, or any number in between. Any jpg generated or changed has a quality number. You choose the number, or you let the software decide. that doesn't answer the question. |
thumbnail sizes
In article , Carlos E.R.
wrote: I've been using this to make thumbnails of jpeg files: for img in *.JPG; do echo thumbnailing $img convert -geometry 105x70 $img $img done Why? Why not use decent software? "convert" is very decent and powerful software. What would you use in a script, then? there's no need to use a script at all. why make things more difficult than they need to be? |
thumbnail sizes
On Jan 7, 2018, Carlos E.R. wrote
(in article ): On 2018-01-08 03:14, Savageduck wrote: On Jan 7, 2018, Carlos E.R. wrote (in ): I wonder why you don't just extract the thumbnails when possible. Don't your cameras create them in the JPGs? It should be quicker and yield better quality images. To customize the size and quality, for instance. Quality for thumbnails? To what purpose? It seems to be a waste of time, and a futile, unnecessary exercise. No. I said "to customize the size and quality" which is different than doing a quality thumbnail. ie, to have thumbnails of the exact quality (small quality) that one wishes. I am still baffled as why these thumbnails have to be produced in the first place. A proof/contact sheet, some sort of project, what? Does it matter? If there is some odd reason to produce them, which has yet to be explained, why would the concept of “quality” be attached to thumbnails of all things? I have been doing this digital photography thing for some time, and I have yet to have the need to produce a thumbnail of any quality. Yes, you do. Any JPG generation has a "quality". It can be "one", so very bad, or it can be "a hundred", so as best as can be, or any number in between. Any jpg generated or changed has a quality number. You choose the number, or you let the software decide. Having a quality does not mean having high quality. ....er, OK. It seems we are talking at cross purposes. While I have produced many JPEGs, I have not gone out of my way to deliberately produce thumbnails. -- Regards, Savageduck |
thumbnail sizes
On 2018-01-08 03:17, Savageduck wrote:
On Jan 7, 2018, Carlos E.R. wrote (in article ): On 2018-01-07 22:22, Savageduck wrote: On Jan 7, 2018, Phillip Helbig (undress to reply wrote (in article ): I've been using this to make thumbnails of jpeg files: for img in *.JPG; do echo thumbnailing $img convert -geometry 105x70 $img $img done Why? Why not use decent software? "convert" is very decent and powerful software. What would you use in a script, then? Why use “convert” which I have never heard of when I have Lightroom, Bridge, and a few others in my photgraphic tool box? Because it is a tool designed for scripts and other repetitive tasks. Most Linux users doing image handling will be familiar with it, but you also have it in Windows, and is used by other tools in the back without telling you. https://en.wikipedia.org/wiki/ImageMagick The tiny code excerpt from the OP would process an entire directory in one click. Or one "enter". As you can see in the documentation, "convert" has dozens of possible options, several pages: http://imagemagick.org/script/convert.php There are also many examples of use. For instance, there is one "-thumbnail": https://www.imagemagick.org/Usage/resize/#thumbnail A whole chapter of it: https://www.imagemagick.org/Usage/thumbnails/ And it has some information that may explain what is happening to the OP: «Many images from digital cameras, scanning software, and some paint programs (photoshop is notorious for this), save extra information about the image in the form of profiles. This includes image formats such a JPEG, PNG, TIFF and as of IM v6.2.4-1 GIF. Of course the IM specific format, MIFF also does this. (See Image Profiles for more detailed information).» «These profiles can be up to 60 Kb in size, so can make a big difference to your file size, and by default IM will preserve this profile information. Thumbnails have no need for this data and often not even the main image needs it.» -- Cheers, Carlos. |
thumbnail sizes
On 2018-01-08 03:49, nospam wrote:
In article , Carlos E.R. wrote: I've been using this to make thumbnails of jpeg files: for img in *.JPG; do echo thumbnailing $img convert -geometry 105x70 $img $img done Why? Why not use decent software? "convert" is very decent and powerful software. What would you use in a script, then? there's no need to use a script at all. why make things more difficult than they need to be? Scripts are trivial to use for automation. What, you do not know...? Wow. -- Cheers, Carlos. |
thumbnail sizes
On 2018-01-08 03:49, nospam wrote:
In article , Carlos E.R. wrote: I am still baffled as why these thumbnails have to be produced in the first place. A proof/contact sheet, some sort of project, what? Does it matter? yes. No. If there is some odd reason to produce them, which has yet to be explained, why would the concept of ³quality² be attached to thumbnails of all things? I have been doing this digital photography thing for some time, and I have yet to have the need to produce a thumbnail of any quality. Yes, you do. Any JPG generation has a "quality". It can be "one", so very bad, or it can be "a hundred", so as best as can be, or any number in between. Any jpg generated or changed has a quality number. You choose the number, or you let the software decide. that doesn't answer the question. Yes. -- Cheers, Carlos. |
thumbnail sizes
In article , Carlos E.R.
wrote: The tiny code excerpt from the OP would process an entire directory in one click. so will other apps, *without* needing to write a script. |
thumbnail sizes
In article , Carlos E.R.
wrote: "convert" is very decent and powerful software. What would you use in a script, then? there's no need to use a script at all. why make things more difficult than they need to be? Scripts are trivial to use for automation. What, you do not know...? Wow. wow what? i know what a script is. the point is there is no need for one when existing apps *already* can do it. |
thumbnail sizes
On Jan 7, 2018, Carlos E.R. wrote
(in article ): On 2018-01-08 03:17, Savageduck wrote: On Jan 7, 2018, Carlos E.R. wrote (in article ): On 2018-01-07 22:22, Savageduck wrote: On Jan 7, 2018, Phillip Helbig (undress to reply wrote (in article ): I've been using this to make thumbnails of jpeg files: for img in *.JPG; do echo thumbnailing $img convert -geometry 105x70 $img $img done Why? Why not use decent software? "convert" is very decent and powerful software. What would you use in a script, then? Why use “convert” which I have never heard of when I have Lightroom, Bridge, and a few others in my photgraphic tool box? Because it is a tool designed for scripts and other repetitive tasks. Most Linux users doing image handling will be familiar with it, but you also have it in Windows, and is used by other tools in the back without telling you. https://en.wikipedia.org/wiki/ImageMagick Interesting. However, I do not use Linux, or Windows, or ImageMagick. The tiny code excerpt from the OP would process an entire directory in one click. Or one "enter". As you can see in the documentation, "convert" has dozens of possible options, several pages: http://imagemagick.org/script/convert.php Did I say that I do not use ImageMagick? I have all sorts of tools I can use (including scripts) for various types of bulk processing. There are also many examples of use. For instance, there is one "-thumbnail": https://www.imagemagick.org/Usage/resize/#thumbnail A whole chapter of it: https://www.imagemagick.org/Usage/thumbnails/ ....and in my opinion, all of that appears to be a royal PIA. And it has some information that may explain what is happening to the OP: «Many images from digital cameras, scanning software, and some paint programs (photoshop is notorious for this), save extra information about the image in the form of profiles. This includes image formats such a JPEG, PNG, TIFF and as of IM v6.2.4-1 GIF. Of course the IM specific format, MIFF also does this. (See Image Profiles for more detailed information).» «These profiles can be up to 60 Kb in size, so can make a big difference to your file size, and by default IM will preserve this profile information. Thumbnails have no need for this data and often not even the main image needs it.» ....but why the need for thumbnails in the first place, or have I missed something? -- Regards, Savageduck |
thumbnail sizes
"Carlos E.R." wrote
| It'd be easier for people to provide a helpful | answer if you'd explain yourself. We're not your | mother. | | Sigh... Maybe he doesn't know what other information to provide, and | you can simply politely ask for what you think you need :-) | And apparently he also can't speak for himself. Maybe *you're* his mother. :) |
thumbnail sizes
On 2018-01-08 04:03, nospam wrote:
In article , Carlos E.R. wrote: The tiny code excerpt from the OP would process an entire directory in one click. so will other apps, *without* needing to write a script. But having to navigate several menus to set the options right. -- Cheers, Carlos. |
thumbnail sizes
In article .com,
Savageduck wrote: There are also many examples of use. For instance, there is one "-thumbnail": https://www.imagemagick.org/Usage/resize/#thumbnail A whole chapter of it: https://www.imagemagick.org/Usage/thumbnails/ ...and in my opinion, all of that appears to be a royal PIA. exactly. And it has some information that may explain what is happening to the OP: Many images from digital cameras, scanning software, and some paint programs (photoshop is notorious for this), save extra information about the image in the form of profiles. This includes image formats such a JPEG, PNG, TIFF and as of IM v6.2.4-1 GIF. Of course the IM specific format, MIFF also does this. (See Image Profiles for more detailed information). These profiles can be up to 60 Kb in size, so can make a big difference to your file size, and by default IM will preserve this profile information. Thumbnails have no need for this data and often not even the main image needs it. ...but why the need for thumbnails in the first place, or have I missed something? still unanswered. |
thumbnail sizes
On 2018-01-08 03:56, Savageduck wrote:
On Jan 7, 2018, Carlos E.R. wrote (in article ): On 2018-01-08 03:14, Savageduck wrote: On Jan 7, 2018, Carlos E.R. wrote (in ): I have been doing this digital photography thing for some time, and I have yet to have the need to produce a thumbnail of any quality. Yes, you do. Any JPG generation has a "quality". It can be "one", so very bad, or it can be "a hundred", so as best as can be, or any number in between. Any jpg generated or changed has a quality number. You choose the number, or you let the software decide. Having a quality does not mean having high quality. ...er, OK. It seems we are talking at cross purposes. While I have produced many JPEGs, I have not gone out of my way to deliberately produce thumbnails. Me neither, but some people do :-) Maybe he wants to have a directory that loads and browses fast with small versions of the photos. Who knows? For instance, somebody I knew generated them in order to create a web page on his home server. The user would see a bunch of photos, click on one and get the large version. So he wanted to generate much smaller versions to optimize load time for the preview. Yeah, sure, there will be some product out there that does it all. Where is the joy in it, instead of doing it yourself completely? Or maybe he was creating one of those "products" :-P -- Cheers, Carlos. |
thumbnail sizes
In article , Carlos E.R.
wrote: The tiny code excerpt from the OP would process an entire directory in one click. so will other apps, *without* needing to write a script. But having to navigate several menus to set the options right. not at all, but even if that were true, it would be much easier than writing (and debugging) a script to do what is *already* built in. not only that, but those apps can also be scripted. |
thumbnail sizes
In article , Carlos E.R.
wrote: ...er, OK. It seems we are talking at cross purposes. While I have produced many JPEGs, I have not gone out of my way to deliberately produce thumbnails. Me neither, but some people do :-) Maybe he wants to have a directory that loads and browses fast with small versions of the photos. Who knows? no point in that when apps do that far better, faster and with far more flexibility. For instance, somebody I knew generated them in order to create a web page on his home server. The user would see a bunch of photos, click on one and get the large version. So he wanted to generate much smaller versions to optimize load time for the preview. couple of clicks to export a webpage that does that (and more). Yeah, sure, there will be some product out there that does it all. Where is the joy in it, instead of doing it yourself completely? Or maybe he was creating one of those "products" :-P if you like making more work for yourself, go for it. it's the linux way. |
thumbnail sizes
On 2018-01-08 04:12, Savageduck wrote:
On Jan 7, 2018, Carlos E.R. wrote (in article ): On 2018-01-08 03:17, Savageduck wrote: On Jan 7, 2018, Carlos E.R. wrote (in article ): On 2018-01-07 22:22, Savageduck wrote: On Jan 7, 2018, Phillip Helbig (undress to reply wrote (in article ): I've been using this to make thumbnails of jpeg files: for img in *.JPG; do echo thumbnailing $img convert -geometry 105x70 $img $img done Why? Why not use decent software? "convert" is very decent and powerful software. What would you use in a script, then? Why use “convert” which I have never heard of when I have Lightroom, Bridge, and a few others in my photgraphic tool box? Because it is a tool designed for scripts and other repetitive tasks. Most Linux users doing image handling will be familiar with it, but you also have it in Windows, and is used by other tools in the back without telling you. https://en.wikipedia.org/wiki/ImageMagick Interesting. However, I do not use Linux, or Windows, or ImageMagick. But the OP is using Linux :-) Can you help him? I don't criticize people for using Windows or whatever. Why have some people got to criticize people for their choices? The tiny code excerpt from the OP would process an entire directory in one click. Or one "enter". As you can see in the documentation, "convert" has dozens of possible options, several pages: http://imagemagick.org/script/convert.php Did I say that I do not use ImageMagick? Then don't post, perhaps? :-P I have all sorts of tools I can use (including scripts) for various types of bulk processing. There are also many examples of use. For instance, there is one "-thumbnail": https://www.imagemagick.org/Usage/resize/#thumbnail A whole chapter of it: https://www.imagemagick.org/Usage/thumbnails/ ...and in my opinion, all of that appears to be a royal PIA. Everybody is entitled to his opinion :-) And it has some information that may explain what is happening to the OP: «Many images from digital cameras, scanning software, and some paint programs (photoshop is notorious for this), save extra information about the image in the form of profiles. This includes image formats such a JPEG, PNG, TIFF and as of IM v6.2.4-1 GIF. Of course the IM specific format, MIFF also does this. (See Image Profiles for more detailed information).» «These profiles can be up to 60 Kb in size, so can make a big difference to your file size, and by default IM will preserve this profile information. Thumbnails have no need for this data and often not even the main image needs it.» ...but why the need for thumbnails in the first place, or have I missed something? Why does it matter? It doesn't to me, at all. -- Cheers, Carlos. |
thumbnail sizes
On 2018-01-08 04:23, nospam wrote:
In article , Carlos E.R. wrote: The tiny code excerpt from the OP would process an entire directory in one click. so will other apps, *without* needing to write a script. But having to navigate several menus to set the options right. not at all, but even if that were true, it would be much easier than writing (and debugging) a script to do what is *already* built in. not only that, but those apps can also be scripted. Yeah, sure :-P -- Cheers, Carlos. |
thumbnail sizes
On 2018-01-08 04:23, nospam wrote:
In article , Carlos E.R. wrote: ...er, OK. It seems we are talking at cross purposes. While I have produced many JPEGs, I have not gone out of my way to deliberately produce thumbnails. Me neither, but some people do :-) Maybe he wants to have a directory that loads and browses fast with small versions of the photos. Who knows? no point in that when apps do that far better, faster and with far more flexibility. For instance, somebody I knew generated them in order to create a web page on his home server. The user would see a bunch of photos, click on one and get the large version. So he wanted to generate much smaller versions to optimize load time for the preview. couple of clicks to export a webpage that does that (and more). Yeah, sure, there will be some product out there that does it all. Where is the joy in it, instead of doing it yourself completely? Or maybe he was creating one of those "products" :-P if you like making more work for yourself, go for it. it's the linux way. Have fun your way, then! :-P -- Cheers, Carlos. |
thumbnail sizes
On 2018-01-08 04:11, nospam wrote:
In article , Carlos E.R. wrote: "convert" is very decent and powerful software. What would you use in a script, then? there's no need to use a script at all. why make things more difficult than they need to be? Scripts are trivial to use for automation. What, you do not know...? Wow. wow what? i know what a script is. the point is there is no need for one when existing apps *already* can do it. Ok, I'll bite. Which one? In Linux, of course. You know all. :-P -- Cheers, Carlos. |
thumbnail sizes
In article , Carlos E.R.
wrote: "convert" is very decent and powerful software. What would you use in a script, then? there's no need to use a script at all. why make things more difficult than they need to be? Scripts are trivial to use for automation. What, you do not know...? Wow. wow what? i know what a script is. the point is there is no need for one when existing apps *already* can do it. Ok, I'll bite. Which one? lightroom and photos both can export photos in whatever sizes the user wants. plenty others. there is also no need to generate separate thumbnails anyway. it's a manufactured problem. In Linux, of course. You know all. :-P no, not in linux. linux has the least amount of available software and most of what does exist for linux isn't particularly good. that's why you have to resort to writing scripts to do basic tasks such as exporting photos. |
thumbnail sizes
In article , Carlos E.R.
wrote: The tiny code excerpt from the OP would process an entire directory in one click. so will other apps, *without* needing to write a script. But having to navigate several menus to set the options right. not at all, but even if that were true, it would be much easier than writing (and debugging) a script to do what is *already* built in. not only that, but those apps can also be scripted. Yeah, sure :-P it's true. |
thumbnail sizes
On Jan 7, 2018, Carlos E.R. wrote
(in article ): On 2018-01-08 04:12, Savageduck wrote: On Jan 7, 2018, Carlos E.R. wrote (in article ): On 2018-01-08 03:17, Savageduck wrote: On Jan 7, 2018, Carlos E.R. wrote (in article ): On 2018-01-07 22:22, Savageduck wrote: On Jan 7, 2018, Phillip Helbig (undress to reply wrote (in article ): I've been using this to make thumbnails of jpeg files: for img in *.JPG; do echo thumbnailing $img convert -geometry 105x70 $img $img done Why? Why not use decent software? "convert" is very decent and powerful software. What would you use in a script, then? Why use “convert” which I have never heard of when I have Lightroom, Bridge, and a few others in my photgraphic tool box? Because it is a tool designed for scripts and other repetitive tasks. Most Linux users doing image handling will be familiar with it, but you also have it in Windows, and is used by other tools in the back without telling you. https://en.wikipedia.org/wiki/ImageMagick Interesting. However, I do not use Linux, or Windows, or ImageMagick. But the OP is using Linux :-) For the task he has in mind, an unfortunate choice. Can you help him? Since he hasn’t responded to any of our questions yet, probably not. Unless of course you are his self-appointed spokesperson. I don't criticize people for using Windows or whatever. Neither do I. Feel free to use Linux, Windows, macOS. However, there is one of those which is not a good choice for phographic work. Why have some people got to criticize people for their choices? So far in this thread there has been no criticism for any choice of OS. However, don’t take offence when it is pointed out that perhaps a particular choice for a specific job is a bad one. The tiny code excerpt from the OP would process an entire directory in one click. Or one "enter". As you can see in the documentation, "convert" has dozens of possible options, several pages: http://imagemagick.org/script/convert.php Did I say that I do not use ImageMagick? Then don't post, perhaps? :-P The OP, Phillip said nothing about ImageMagick, you did. He said that he was using a script to make thumbnails. I have all sorts of tools I can use (including scripts) for various types of bulk processing. There are also many examples of use. For instance, there is one "-thumbnail": https://www.imagemagick.org/Usage/resize/#thumbnail A whole chapter of it: https://www.imagemagick.org/Usage/thumbnails/ ...and in my opinion, all of that appears to be a royal PIA. Everybody is entitled to his opinion :-) Well, you have mine. And it has some information that may explain what is happening to the OP: «Many images from digital cameras, scanning software, and some paint programs (photoshop is notorious for this), save extra information about the image in the form of profiles. This includes image formats such a JPEG, PNG, TIFF and as of IM v6.2.4-1 GIF. Of course the IM specific format, MIFF also does this. (See Image Profiles for more detailed information).» «These profiles can be up to 60 Kb in size, so can make a big difference to your file size, and by default IM will preserve this profile information. Thumbnails have no need for this data and often not even the main image needs it.» ...but why the need for thumbnails in the first place, or have I missed something? Why does it matter? It doesn't to me, at all. However, there is something pointless about the idea. -- Regards, Savageduck |
thumbnail sizes
"Savageduck" wrote
| Can you help him? | | Since he hasn't responded to any of our questions yet, probably not. Unless | of course you are his self-appointed spokesperson. Maybe Carlos and Phillip are 2 aliases for the marketing person at ImageMagick. That would explain a lot. Phillip asked what seems to be an unimportant question in an almost childish way, with no context, and then checked out. While Carlos uses every post to sing the praises of ImageMagick. I've looked into ImageMagick before as a possible programming tool for graphics operations. I've never seen the sense of it. As a resource for programming it's very clunky and indirect, having no value in actual usage because the operations are all inside. A programmer is a cook. ImageMagick is a waiter's order window. You tell it what you want. It loads an image, does that operation, then resaves the image. As a command-line tool.... A vast collection of graphic editing functions that only work from the command line? Only Linux people could think that makes sense. Here's an example of drawing a line across an image, from their drawing tutorial: convert rose: -fill none -stroke white -draw 'line 5,40 65,5' rose_raw.png How do you know the coordinates to draw from/to without a GUI? You don't, of course. Then that one operation has to resave the image. It's nonsensical. But I suppose he has a point in a very limited context: If you only have Linux and if you don't have any tool to do batch thumbnail production... and that's what you want to do... and you don't mind spending a couple of hours learning commandline incantations... and you don't much care about the quality of the thumbnails... then ImageMagick might be a very good choice. It could also be handy for similar, simple batch tasks like resizing hundreds of images. But on Windows (and no doubt on Mac) there are plenty of options for things like that. |
thumbnail sizes
On Jan 8, 2018, Mayayana wrote
(in article ): wrote Can you help him? Since he hasn't responded to any of our questions yet, probably not. Unless of course you are his self-appointed spokesperson. Maybe Carlos and Phillip are 2 aliases for the marketing person at ImageMagick. That would explain a lot. Phillip asked what seems to be an unimportant question in an almost childish way, with no context, and then checked out. While Carlos uses every post to sing the praises of ImageMagick. I've looked into ImageMagick before as a possible programming tool for graphics operations. I've never seen the sense of it. As a resource for programming it's very clunky and indirect, having no value in actual usage because the operations are all inside. A programmer is a cook. ImageMagick is a waiter's order window. You tell it what you want. It loads an image, does that operation, then resaves the image. As a command-line tool.... A vast collection of graphic editing functions that only work from the command line? Only Linux people could think that makes sense. Here's an example of drawing a line across an image, from their drawing tutorial: convert rose: -fill none -stroke white -draw 'line 5,40 65,5' rose_raw.png How do you know the coordinates to draw from/to without a GUI? You don't, of course. Then that one operation has to resave the image. It's nonsensical. But I suppose he has a point in a very limited context: If you only have Linux and if you don't have any tool to do batch thumbnail production... and that's what you want to do... and you don't mind spending a couple of hours learning commandline incantations... and you don't much care about the quality of the thumbnails... then ImageMagick might be a very good choice. It could also be handy for similar, simple batch tasks like resizing hundreds of images. But on Windows (and no doubt on Mac) there are plenty of options for things like that. I agree. While Linux has a place in the computing spectrum, it is not the most sensible choice for most folks when it comes to doing anything productive with photography, or graphics. There is a reason that the great majority of photography, and graphics software is only written for, and supported by WIN, and/or macOS. At this point in this thread I would have expectedthat we would have heard from Floyd Davidson to challenge that assertion. I am surprised that he hasn’t as he has been the champion of Linux, and GIMP in this NG. Floyd, like many of us in this NG is no youngster, so I hope that he is in good health up there above the Arctic Circle in Barrow. Regardless of his support of all things Linux, Floyd is knowledgeable with regard to many photography, and technology related things, and would probably have had an answer that Carlos would have approved of. -- Regards, Savageduck |
thumbnail sizes
In article , Mayayana
wrote: But I suppose he has a point in a very limited context: If you only have Linux and if you don't have any tool to do batch thumbnail production... welcome to linux. and that's what you want to do... and you don't mind spending a couple of hours learning commandline incantations... and you don't much care about the quality of the thumbnails... then ImageMagick might be a very good choice. yep. It could also be handy for similar, simple batch tasks like resizing hundreds of images. But on Windows (and no doubt on Mac) there are plenty of options for things like that. yep. |
All times are GMT +1. The time now is 08:25 PM. |
|
Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
PhotoBanter.com