|In this tutorial I want to tell us an interesting experiment I did with the textures: this experiment, that you can easily reproduces with your own pictures, will give you valuable guidance on how to best manage texures of your models, improving the quality and even saving space in filesize!||IMPORTANCE
you can download the model used for this experiment in 3Dwarehouse by clicking on icon above
Carefully examining several models in 3dwarehouse, I have noticed that very often the skp files are unnecessarily too weight ... because of the excessive size of the images used for textures! In fact, the images are often unpleasant things – or bad and ugly beast - for most modelers, because they don’t know how to treat them, and believe that bigger images cause automatically higher quality. My experiment would dispel this prejudice and give you some useful guidance to tame these wild animals.
PREPARING THE EXPERIMENTStep 1. OBTAINING 20 DIFFERENT PICTURES (USING A GRAPHIC TOOL) Before building the model skp, I uploaded into my Photoshop Elements an image of the famous, full of grace picture “La Primavera” from wich I’ve carved a square detail of about 900x900 pixels. From this square detail I have gradually reduced the size, first at 800x800, 600x600, 400x400 and 200x200 pixels.
From each image thus obtained I created 5 jpeg files, with different quality factors, id est with 0 = minimal, 10 = low, 30 = average, 60 = high and 100 = maximum quality. For the 200x200 picture I’ve created 5 files: P200_00.jpg, P200_10.jpg, P200_30.jpg, P200_60.jpg, P200_99.jpg with these sizes: 5 kb, 7 kb, 11 kb, 19 kb, 56 kb For the 400x400 picture I’ve created 5 files: P400_00.jpg, P400_10.jpg, P400_30.jpg, P400_60.jpg, P400_99.jpg with these sizes: 18 kb, 23 kb, 37 kb, 70 kb, 206 kb And so on… Step 2. PAINTING THE FACES IN THE MODEL (IN SKETCHUP) The model used for the experiment was divided into four sections: Section A the 20 squares are painted using the 20 textures from the files created in Step 1 Section B here are the details corresponding to each square of A Section C this is THE HEART of the experiment, in wich are reported a few significative specimens of the B identified by a little red triangle Section D this is an appendix for a special case
Now our environment is OK and we can examine, slowly and quietly, our wild animals…
DISCUSSING THE EXPERIMENTI suggest you to begin from Section C - What is the pictures quality? What is the worst and what the best picture? What is the corresponding weight in kbytes of corresponding textures? The assumption “The greater the size of the JPEG file, the better the image quality?” is true, isn’t it? Or not!? Now we can begin to make some hypothesis, and we can check them on the section B which also shows, neatly, all other details. Here we note that each time we board a row there is a definite breakthrough in quality, while the other hand, within the same line, the improvement in quality does not seem too equally obvious. At this point I advise you to consult and carefully look the Section A, in which are clearly marked on all the characteristic elements of the file used for texturing the squares. Finally, I suggest you carefully examine the different textures on the rows and columns carrying out all possible comparisons – closely and at medium and long distances.
RECOMMENDATIONS AND CONCLUSIONSThe first conclusions are:
|If you know of other interesting articles on this topic, or if you have any remark or comment, please use the COMMENTS area to share with us all your experiences!|