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Posting an image?

by pivoxa15
Tags: image, posting
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pivoxa15
#1
Dec17-06, 01:42 AM
P: 2,268
I like to post about 500kB images when placed in Word or Paint exceeds the maximum limit that can be uploaded. Are there any suggestions about how I could post these images in another fashion?

Thanks
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3trQN
#2
Dec17-06, 01:48 AM
P: 349
Try putting them on ImageShack and link to them with the image tags, not sure if they have a size limit though.

Also, word/paint may not be the best at optimising an image, the format also effects the file size.
dontdisturbmycircles
#3
Dec17-06, 01:48 AM
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If I understand your question correctly, you are looking for a way to upload images and display them in a thread. I suggest that you use www.imageshack.us

Simply browse for your file, and upload it. At the page that pops up after you do that, at the very bottom, is a line that says "Direct link to image", go ahead and copy that.

Then in a thread use the tags "[img]" and "[ /img]"(no space) and put your URL for the direct link inbetween those tags.

dontdisturbmycircles
#4
Dec17-06, 01:49 AM
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Posting an image?

woops, sorry 3trQN, you snuck in before me.
3trQN
#5
Dec17-06, 01:53 AM
P: 349
'tis OK you did a much more thorough explanation than me :)
ZapperZ
#6
Dec17-06, 05:55 AM
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Note that the img tags will only display an image in the General Discussion forum. All other forum will only display the link within the posting, not the image.

Zz.
neutrino
#7
Dec17-06, 07:09 AM
P: 2,047
Best solution is to link to an image hosting site as mentioned above. When placing images in paint, save them as a jpg or gif (and crop them to a reasonable size). bmp's take up a lot of space.
pivoxa15
#8
Dec24-06, 06:30 PM
P: 2,268
Quote Quote by neutrino View Post
Best solution is to link to an image hosting site as mentioned above. When placing images in paint, save them as a jpg or gif (and crop them to a reasonable size). bmp's take up a lot of space.
That is amazing, a 380kb bmp went to 8.3kb when saved as jpg.
russ_watters
#9
Dec24-06, 09:23 PM
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Yah....learn about image compression and resolution. It's a critical computer/internet skill.

That said, a 380K image won't generally look good compressed to 8.3K unless it is a very simple image...
pivoxa15
#10
Dec24-06, 10:49 PM
P: 2,268
Quote Quote by russ_watters View Post
Yah....learn about image compression and resolution. It's a critical computer/internet skill.

That said, a 380K image won't generally look good compressed to 8.3K unless it is a very simple image...
Good idea. How would you recommand me learn these computer skills? Comptuers change very fast and so it can be hard to know which ones are more worthwhile to learn.

The image I posted was a simple image of a handrawn picture in Paint. It didn't look too bad as a 8.3k.
Evo
#11
Dec25-06, 09:24 PM
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Quote Quote by pivoxa15 View Post
Good idea. How would you recommand me learn these computer skills? Comptuers change very fast and so it can be hard to know which ones are more worthwhile to learn.

The image I posted was a simple image of a handrawn picture in Paint. It didn't look too bad as a 8.3k.
Understanding the ratio of pixels to inch isn't hard and is standard. The higher the resolution (higher number of pixels to inch) the better quality the picture will be.
russ_watters
#12
Dec26-06, 12:24 AM
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Well, for starters, if you right click your desktop and click "properties", then "settings", it'll tell you your display resolution. A picture that you want to display on the internet should be some fraction of that (say, 800x600). As evo said, higher resolution means more bytes (and it is an exact ratio: a 1600x1200 image is exactly 4 times as big as an 800x600 image).

For compression, an image on your screen is just a matrix (a referenced list) of pixels and their colors. Jpeg compression works by grouping colors in adjacent pixels together and only listing them once. Obviously, then, a picture of a clear blue sky or a black on white sketch is extremely compressible because there are a lot of adjacent pixels of exactly the same color. A photo with medium detail can be compressed by 90% at 90% quality (a good rule of thumb when you are saving images for the web - it is in the options for every photo editor). As you found, a pencil sketch on a white background can be compressed 100x with little loss in quality.

As for how to learn, gee, I'm not exactly sure how I did. I guess it was some combination of trial and error and doing what other people did. I do remember a very specific time in '95 or '96 when the internet (as we know it today) was young when I downloaded a photo (an X-plane from the Dryden website) and started playing with compression ratios to see how they came out.
DaveC426913
#13
Dec26-06, 01:17 AM
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Quote Quote by pivoxa15 View Post
Good idea. How would you recommand me learn these computer skills? Comptuers change very fast and so it can be hard to know which ones are more worthwhile to learn.

The image I posted was a simple image of a handrawn picture in Paint. It didn't look too bad as a 8.3k.
It's very simple for most purposes.

If your image is photographic in nature or has subtle, complex shading of colours, save it as a jpg.
If your image is simpler than photographic (such as your hand-drawn pic), save it as a gif.

Either way, when saving, it's up to you to decide how high quality you need it to look to your viewers. Save at the lowest quality (smallest filesize) that will meet your purposes (gifs and jpgs do this in different ways. With jpgs you increase compression rate, whereas with gifs you reduce number of colours).

BTW, don't underrate the effect that a smaller picture size will have on the filesize! Halve the dimesions of the pic, you quarter the filesize.

That will take care of 90% of your picture saving needs.
jtbell
#14
Dec26-06, 10:52 AM
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Quote Quote by DaveC426913 View Post
IIf your image is photographic in nature or has subtle, complex shading of colours, save it as a jpg.
If your image is simpler than photographic (such as your hand-drawn pic), save it as a gif.
When I make a drawing by hand and scan it, I save it first as a TIFF file which is usually huge (several megabytes). Then I open it in Photoshop (most other image editors can probably do what I'm going to describe), and use the "Levels" adjustment to make all the grey shades in the paper background pure white, and make the "ink" in the drawing as dark and uniform as possible without obscuring details. Then I save it as a GIF. The fewer colors or shades a picture has, the more efficiently the GIF algorithm works and the smaller the resulting file.

If you make the drawing on the computer using drawing software, it will probably have only a few colors and shades already, or even just black and white, so you can save it directly as a GIF.
DaveC426913
#15
Dec26-06, 11:07 AM
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Quote Quote by jtbell View Post
When I make a drawing by hand and scan it, I save it first as a TIFF file which is usually huge (several megabytes). Then I open it in Photoshop (most other image editors can probably do what I'm going to describe), and use the "Levels" adjustment to make all the grey shades in the paper background pure white, and make the "ink" in the drawing as dark and uniform as possible without obscuring details. Then I save it as a GIF. The fewer colors or shades a picture has, the more efficiently the GIF algorithm works and the smaller the resulting file.
Yeah that's kinda what I do too.

Hey, are you a sketch artist? Post some of your stuff?
jtbell
#16
Dec26-06, 10:48 PM
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Well, my "artistry" is limited to simple diagrams. I've done a few in the relativity forum, but when I do a search for my own postings, I can't tell which ones have attachments without actually looking at them. Or maybe I just haven't come across one in the listings yet.


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