Uploaded textures fixed at 256x256

Hi newbie question I am sure.
I have tried uploading jpegs of various sizes 1024 x 768. Or cropped to other odd sizes ... 456 x 678. Whatever ... but they preview at 256 x 256 and they upload as 256 x 256 distorting the crap out of the picture.
I dont see any options to change the texture size in sl ... and my friends tell me their pictures/textures upload at whatever resolution the original jpeg is.
Any ideas?
Thanks

Texture sizes must be a power of 2. If not, SL rescales them down.

Also, you don't resize/rescale textures once they are uploaded. You can use the Edit/Texture options after you apply them to a prim.

I was wondering about this as well - I have uploaded images in the past at larger sizes that have come in correctly, but for some reason the images I uploaded last night came in at 256x256 regardless of what size they originally were. I gave up rather than spend more $ trying to figure it out.

Either we're both doing something wrong or this is a new glitch.

Which viewer version & operating system version are you using? Could be a bug with a specific viewer/os.

-peekay

thanks for the replys .
I don't think it is the power of 2 solution. The standard resolution of the untouched photographs is a power of 2 and they come in at 256 x 256 also.

And I am really just talking about uploaded photos ... not necessarily a texture to apply to a prim.

Viewer soft ware (also used to edit ) is simply ms picture manager 11.6550.6568.
Operating system is windows xp sp 2.
or at least I think that is what you were asking about.

/shrug

The folowing are the valid power of 2 image dimensions

2
4
8
16
32
64
128
256
512
1024

Your image can be any combination of those for width / height. Any width or height that is not one of those numbers will be resized down to the nearest one.

Hi Reyal, sorry I wasn't clear; I meant which version of the Second Life program you are using (there is the standard viewer and also the "First Look" viewer.)

The version number is displayed on the login screen (bottom-right corner) and also from the Help -> About Second Life menu.

I tried with both the standard viewer (1.13.3(2)) and the latest First Look (on Windows) and was able to upload correctly, however.

Are these JPG images? Maybe you can post a sample image that's getting uploaded incorrectly?

-peekay

Something like 456x678 is not an appropriate texture size. As has been mentioned, all textures must be measurable in powers of two. This is a requirement of OpenGL. Any oddball sizes like that will get downsized at the time of upload to the closest power of two. So, 456x768 should end up being 256x512. Of course, it's a lot better to do the resizing yourself in Photoshop since the results will look a lot nicer, but if you don't, SL will do it for you, just not as well.

By what criteria are you judging that everything is coming out 256x256, by the way? Don't go by the size of previewer window. I'd be willing to be the texture you mentioned is actually 256x512, even if the viewer window is buggy enough to display it as a square instead of a rectangle (which it often does). When you open a texture, look in the lower left hand corner of the viewer window. It will say what the dimensions are.

For more info on texture sizing, see the sticky on the texturing forum: /109/e6/150360/1.html

Whether or not you intend to apply the texture to a prim, there is only one way to upload an image file and it needs to be in the power of 2 dimensions to avoid the lossy SL re-size. "Texture" means "image file" in this context.

Okay, if you're uploading images with an X or Y dimension that is greater than 512 and still always getting 256x256 then that's a bug. However, if it's just the power-of-two resizing issue, here's a tip for making sure that images that you upload maintain the proper dimensions for viewing- for example in a greeting card or wall art in your home:

1. In Photoshop, when you save your image, add the true dimensions of the picture to the name. For example, if I had a picture named "My Cat" that was 746x572 in Photoshop, I'd name the file: My Cat 746x572.tga
   
2. Upload the texture into Second Life and create a prim to use as a canvas for your image. Decide generally how big you want the picture- for example, maybe you want to make a poster that's 2 meters wide. Size the prim so that the longest dimension (whether it be height or width) is the size that you want.
   
3. Apply the uploaded texture to the prim. (As an aside, I like to use the 'Select Texture' feature in the edit window. When you choose that and click the face of the prim you want to texture twice, it will select JUST THAT FACE and leave the rest of the prim alone. For cards and portraits, sometimes I'll texture the front and back so that you can see the image regardless of the viewing angle when the object rezzes.)
   
4. Now grab your calculator and determine the correct size for the other dimension of your viewing prim. So for our above example, we've got an image that was originally 746x572 pixels (now uploaded as a 512x512 texture), and we already decided that we want our poster to be 2 meters wide. Divide the longer dimension of your original image by the shorter dimension, rounding to three digits: 746/572 = 1.304. Next, divide the longest dimension of your viewing prim by the result of the previous equation: 2/1.304 = 1.534.
   
5. Use the result of the above equation to set the height of your viewing prim. The resulting size to properly represent the image described above would be 2mx1.534m.
   
6. If you ever need to resize the canvas to fit someplace, just make sure to use the gray stretch handles instead of the colored ones, so you preserve the dimensions of the original. If you mess up, you've still got the correct pixel size in the texture name, so you can recalculate and fix it.
   

I uploaded several 1024 x 512 wall murals last night, and they came through just fine, using the standard client. Probably the original poster was using the First Look beta cleint. That version number looked like First Look's version to me.

Ok ... Math is just not my strong suit .
Turns out it was the power of 2 problem. I forgot I was compressing all the pictures to "web sized". It didnt make sense why my 1024 x 768 pictures were coming out 256 x 256. But they were really 452 x 342 after compression.

Thanks for the help

I'm usually lazy about the math... I'll just start by creating a prim that is 7.46 x 5.72 meters (that is, just put an appropriate decimal point in the original pixel dimensions and use it as the size in meters), apply the texture, and then use the gray corner handles to stretch or shrink it to an appropriate size. But if you need a prim where one dimension is an exact size, it's calculator time.