Resizing Images

[raphy]

No, there aren't any naked pictures here. Well, there might be, depending on whether people post any - But I'll not be posting any. My AmPics thread lived a brief but glorious life about 2 years ago. (actually, this should probably be in How-To, but I don't know how many AmPics people look on that board)

No, this isn't about me. This thread is for anyone and everyone who wants to take pictures, but doesn't know how to resize the overly large and unwieldy pictures taken by most digital cameras today. Seriously. Digital camera manufacturers seem to think we're all David Bailey or something, and we all need 3 gazillion megasuperduper pixel hi-def Pulitzer-prize winning images.

Wait, do they even award the Pulitzer for photography? I have no idea. That's why I'm not a journalist, writer or photographer, I guess. .

Anyhoo, I am aware that there are people out there with:

a) Slow modems.
b) Small monitors. (Doesn't everyone say size isn't important?)
c) Large images.

or

d) all of the above.

So people will slow modems and small monitors can't view large images, because it forces them to scroll. People with better systems and better digital cameras can't upload their pictures to lit because lit has as maximum filesize and resolution.

Wait, Raph, what's resolution?

Well gee golly gosh, I'm glad you asked.

See, there's two aspects to digital imaging. Resolution and compression. Let's talk about resolution first.

Resolution generally means the number of pixels that go into making up the image. It also commonly refers to the height and width of the image in pixels.

A very 'standard' resolution for windows desktop computers these days is 1024x768. That means that there's 1024 pixels across the top, and 768 pixels down the side.

That seems like an awful lot of pixels, Raph, why can't I view some of the images I take on my 3.1 megapixel camera?

Well, a 3.1 megapixel image is, as you have probably guessed, an image that contains 3.1 million pixels.

Taking 1.33 as the standard aspect ratio for screens (Width divided by height), an image that contains 3.1 million pixels is actually 2048 wide by 1536 high. Your standard computer monitor can display 72 pixels per inch (some go to 96), so in order to view that at full size you'd need a monitor that was 28 inches wide or thereabouts (2048 divded by 72)

Remember, 1.3 megapixels is 1.3 million pixels. Your 1024 by 768 monitor can display 1024 times 768 pixels, which is 786432 pixels. And that's a lot less than 1.3 million, I think you'll agree.

So why do they make digital cameras that take pictures at such a high resolution? For printing. While your computer monitor may only be able to display 72 dots in an inch, magazines and other professional printing uses use far more, 300, 600 and up.

If you're printing 600 pixels in an inch, suddenly your 1.3 million pixel image becomes a lot more manageable.

But I'm digressing. I'm supposed to be talking about resolution. Not print quality. So resolution is important to digital images, because of the limitations of computer monitors. It's also important for another reason, which brings me to the next part of digital imaging: Image quality and file size.

A 1024 by 648 image will have many more pixels than a 640 by 480 image, obviously. That means that it takes up more space to store that image on your hard drive (simply due to there being more pixels involved in the image)

However, there are ways to reduce the file size of the image without actually reducing it's physical size. jpg, a popular image format on the internet looks at each block of 8x8 pixels and decides whether it can cheat and reduce the number of bytes needed to store the color data for that block.

For example, a picture of a blue screen can be easily compressed, because all the pixels are mostly the same color, so the image data can cheat. It can say 'most of these pixels are blue, except for this one, this one and this one', which in computer terms works out to much less file space than saying 'blue pixel, blue pixel, blue pixel, blue pixel, blue pixel, blue pixel, blue pixel' a gazillion times.

A picture of a brightly-colored hummingbird is not so easy to compress, because the colors change dramatically and in small areas.

There are, of course, different levels of compression. The more you compress an image, the poorer the quality. The trick is to find the balance. The human eye, generally speaking, doesn't have a particularly good resolution. We think we do, because our brains are pretty clever and fill in the gaps, or smooth out the edges, but in reality, we're probably worse than the average scanner you can buy at Best Buy.

So there's a compromise to be found between image quality and file size.

So, now that I've probably bored you all to death, I suppose I should go back to the reason why I started this thread:

How to post pictures on lit that lit won't accept.

Lit won't accept pictures for 2 reasons:

a) The image dimensions are too large.
b) The file size of the image is too large.

So, given those two rules, and all that crap I posted above, how do we actually get our 1.3 megapixel image to post on literotica?

Well, it just so happens that I have a handy-dandy walkthrough guide all ready and prepared for you all. For this walkthrough, I'll be using a piece of software called Irfanview, which you can get from their webside irfanview.com - It is 100% free for private non-commercial use, and contains all the functionality that you need to be able to resize and compress your digital camera images.

And with that, on with the walkthrough.......

 

[raphy]

Step 1 - The image.

Here's a picture. It's actually my current desktop and it's the most beautiful car in the world. Well, maybe beautiful is the wrong word to describe this car. Anyway. It's my dream car. It's 600 horses of British Beef all wrapped up in a Saville Row suit with more leather than the living rooms of most houses.

The original of this picture is 1024 pixels wide by 768 pixels high, and in bitmap (bmp) form weighs in at a little under 2.5 megabytes. Waaaay too big for lit. Even in jpg form, it's 168k, which is still too big for lit. And besides, 1024x768 fills a lot of people's monitors and I don't know about you all, but I never run my web browser full-screen.

Anyway.. In the screenshot, I have it opened up in irfanview, all ready for resizing and compressing.

 

[raphy]

Step 2 - The Resizing.

See? isn't it a sexy car? The Aston Martin Vantage, and in British Racing Green too. Good stuff.

Now, you click on Edit and then Resize. In the resize box there's a few options, all of which look confusing. I've drawn little circles around the only ones you need to worry about.

The first picture shows where the Resize option is. The second shows the resize window that comes up, and the 3rd is a zoom-in on that window. I've drawn a red circle around the stuff you'll need to change, but before you go typing numbers into boxes, let me draw your attention to the blue circle at the bottom of the image. That's the 'preserve aspect ratio' checkbox. You'll want to leave that checked (or check it if it is unchecked. That preseves the ratio between the height and width of your picture, and you mess with that any, you'll end up with a picture that looks kinda like trying to view widescreen TV on a regular TV without the top and bottom borders.

What to put into that box? Well, it's really up to you, but the first thing you have to think about is - Which is my longest dimension? Height, or width? I usually found that putting something between 500 to 600 in the box corresponding to my longest dimension seemed to work okay for me.

Remember, we're aiming on reducing the image dimensions *and* the file size of the image to get it posted on literotica.

You'll find that you only need to enter a value into *one* of the dimension boxes (either height or width), because the program will figure out what the other one is based on the current dimensions. It's clever like that.

 

[raphy]

Step 3 - Saving and Compressing.

Now your image is resized. That's (hopefully) fixed the resolution requirements for literotica. Now we have to deal with the image size (if necessary). In irfanview (and most picture editors) the compression is done at the same time as you save the image.

I've put a bunch of screenshots up for this stage too, although I'm sure you all won't need the first few.

The first one is simply a screenshot marking where the 'save' button on irfanview is.
The second shows what the save window looks like. See that weird window sticking out to the left. We'll be looking at that in a moment.
The third is a zoom in on the save as boxes. You'll probably want to pick jpg as your format to save it in. Also, don't save over your original file.
The fourth is a zoom in on that new weird window that was on the left. This is where you can set exactly how much you want to compress your image. The little slider moves from the left to the right. Right is zero compression, full quality. Left is maximum compression, zero quality.

I've set mine to 80% - that's quality, not compression. So 20% compression, just to reduce the file size a little, without losing any noticable (to human eyes) quality in the image.

Experiment with the settings. Maybe you'll find different ones work for you.

Save the image, and that's it, you're done. There was an awful lot of typing in these posts, but really, it's not a very complicated procedure. 3 stages, that's all. Open the image. Resize the image. Save (and compress) the image.

 

[raphy]

And here's the final resized image - Resized to 600x450 pixels, and weighing in at a much trimmer 59Kb

I hope this thread helps those of you who are having trouble trying to post pictures directly from a digital camera to lit and getting file too big errors.

If we're lucky maybe one of the mods will happen along here and sticky this for future AmPics posters that have the same problems!

Best wishes to all of you!

Raph