After discussion with some people (especially Tannin) on the en.wikipedia, I propose a few changes (more like additions) to the thumbnail function.
Here's the "main proposal":
[[image:bla.jpg|thumb|some text]] generates a normal thumbnail [[image:bla.jpg|thumb=bla_small.jpg|some text]] uses "bla_small.jpg" as the thumbnail
This associates the manually created thumbnail with the larger image in a machine-readable fashion. It should only be used if the manual thumbnail is of significant better quality than the automatic one, or if the manual thumbnail shows an alternate view (e.g., only a part) of the larger image.
Additionally, the automatic thumbnail generation should be improved: * Add a little sharpening, at least to photos (.jpg/.jpeg). * Apparently, automatically generated thumbnails look nicer when they are recaled by an exact even number. For example, for a 640x480 image, a thumbnail of 200px is requested, generate one with a width of 213px instead, as this is a factor of 33.3%, or 1/3. I propose to use a variation of up to 10% from the requested width.
If there is no special reason *not* to do this, implementation can start soon. At least the "main proposal" should be easy enough to code.
Magnus
Magnus proposed some improvements to the thumbnail function, notably:
[[image:bla.jpg|thumb|some text]] generates a normal thumbnail [[image:bla.jpg|thumb=bla_small.jpg|some text]] uses "bla_small.jpg" as the thumbnail Add a little sharpening, at least to photos (.jpg/.jpeg). Other stuff
This is an excellent and much-needed improvement. As I have documented at length on his en wiki talk page (among other places), the current thumbnailing method produces significantly sub-optimal results. This will deal with the criticisims I and others have made, and provide a major improvement in our visual presentation.
(PS: the styling of the thumbnail boxes is still pretty ordinary: some attention to the CSS would also be good.)
Tannin (Tony Wilson)
Magnus-
- Apparently, automatically generated thumbnails look nicer when they
are recaled by an exact even number. For example, for a 640x480 image, a thumbnail of 200px is requested, generate one with a width of 213px instead, as this is a factor of 33.3%, or 1/3. I propose to use a variation of up to 10% from the requested width.
Please don't do this. It would break many layouts (e.g. multiple images aligned horizontally or vertically, images in fixed width tables ..) and be very confusing.
Regards,
Erik
I pointed out (elsewhere) that thumbnail image quality is better when the rescale uses an exact even number. (50%, 33.3%, etc.). (Not under all circumstances, by the way. It depends of the resolution of the source image. In general, the larger the original the less it matters.)
Magnus proposed that the software generate a thumbnail *close* to the requested size (and thus preserve as much image quality as possible, at the cost of producing (e.g.) a 213px rather than a 200px thumb.
Erik said please don't do it as it would break many layouts.
Ahh! I hadn't thought of that!
No matter. Exact fraction resizes are really only required for a small proportion of images - off the top of my head, maybe 10%. These can be hand-thumbnailed instead. As it happens, it is low to medium-resolution originals that tend to have the worst problems when autothumbnailed, and benefit most from human intervention, so the reality is that we were probably going to want to hand-thumbnail most of the images that could benefit from the (e.g.) 200 to 213px rescale anyway, so we can simply leave the even-fraction rescale part out of the overhaul and not particularly miss it.
Tannin (Tony Wilson)
On Thursday 01 July 2004 18:04, Tony wrote:
Magnus proposed that the software generate a thumbnail *close* to the requested size (and thus preserve as much image quality as possible, at the cost of producing (e.g.) a 213px rather than a 200px thumb.
Erik said please don't do it as it would break many layouts.
it might be a solution to modify the code, such that
[[image:bla.jpg|thumb|200px ...]]
gives the old result and
[[image:bla.jpg|thumb|~200px ...]]
means that you want something which is roughly ~200 px (+-10% with the advantage of a slightly higher quality). At least this would solve the above mentioned problem and the notation would make some sense to me.
best regards, Marco
I have summarized all proposed changes on http://meta.wikipedia.org/wiki/Thumbnails
Marco Krohn wrote:
it might be a solution to modify the code, such that
[[image:bla.jpg|thumb|200px ...]]
gives the old result and
[[image:bla.jpg|thumb|~200px ...]]
means that you want something which is roughly ~200 px
So funny, I thought of the exact same syntax befor I reached your mail in the thread. Must really be intuitive! :-)
Magnus
On Thursday 01 July 2004 18:04, Tony wrote:
I pointed out (elsewhere) that thumbnail image quality is better when the rescale uses an exact even number. (50%, 33.3%, etc.). (Not under all circumstances, by the way. It depends of the resolution of the source image. In general, the larger the original the less it matters.)
Magnus proposed that the software generate a thumbnail *close* to the requested size (and thus preserve as much image quality as possible, at the cost of producing (e.g.) a 213px rather than a 200px thumb.
Erik said please don't do it as it would break many layouts.
As I said, specifying image width to 200 in HTML will show an image 200 pixels wide even if the image in the file is 213 pixels wide.
OTOH, browsers actually achieve that by re-scaling the image; it might end up with the same problem but now at the client side.
On Sat, 10 Jul 2004 12:01:11 +0200, Nikola Smolenski smolensk@eunet.yu wrote:
As I said, specifying image width to 200 in HTML will show an image 200 pixels wide even if the image in the file is 213 pixels wide.
OTOH, browsers actually achieve that by re-scaling the image; it might end up with the same problem but now at the client side.
That's correct; the browser would simply resize the image and you'd have the same image quality issues all over again.
If somebody requests a thumbnail that's 200px wide, they should get a thumbnail that's 200px wide. I don't see any problem with telling them that one 213px wide would look better, but the choice should be theirs.
-Bill
On Sat, 10 Jul 2004 08:20:35 -0400, Bill Clark wclarkxoom@gmail.com wrote:
If somebody requests a thumbnail that's 200px wide, they should get a thumbnail that's 200px wide. I don't see any problem with telling them that one 213px wide would look better, but the choice should be theirs.
Exactly- there should be a way to say "about 200px wide, whatever size looks best in that region".
On Sat, 10 Jul 2004 12:43:39 -0400, Fennec Foxen fennec@gmail.com wrote:
Exactly- there should be a way to say "about 200px wide, whatever size looks best in that region".
Maybe the sizing option could be given as both a dropdown (with precisely 1/2 size, 1/3 size, 1/4 size, etc.) and a regular text input that allows arbitrary dimensions.
Or a checkbox that says "allow the dimensions to vary slightly, to improve image quality."
I think the second way would be better, but that's just me.
-Bill
IMHO the argument "~200px" is very nice (I don't recall who suggested it). "1/3" or "25%" could also be supported.
BTW, I just commited the "thumb=xyz.jpg" option to CVS HEAD. That seemed to be the primary concern. I'll get to the other things later.
Magnus
Bill Clark wrote:
On Sat, 10 Jul 2004 12:43:39 -0400, Fennec Foxen fennec@gmail.com wrote:
Exactly- there should be a way to say "about 200px wide, whatever size looks best in that region".
Maybe the sizing option could be given as both a dropdown (with precisely 1/2 size, 1/3 size, 1/4 size, etc.) and a regular text input that allows arbitrary dimensions.
Or a checkbox that says "allow the dimensions to vary slightly, to improve image quality."
I think the second way would be better, but that's just me.
-Bill _______________________________________________ Wikitech-l mailing list Wikitech-l@Wikipedia.org http://mail.wikipedia.org/mailman/listinfo/wikitech-l
On Thursday 01 July 2004 09:26, Magnus Manske wrote:
- Apparently, automatically generated thumbnails look nicer when they
are recaled by an exact even number. For example, for a 640x480 image, a thumbnail of 200px is requested, generate one with a width of 213px instead, as this is a factor of 33.3%, or 1/3. I propose to use a variation of up to 10% from the requested width.
Sometimes people might need images EXACTLY so-and-so wide. I'm for this if it would still create <img width=200 ...> tags with actual image being 213px wide.
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