Millisecond Forums

Your display has a limited amount of pixels. If the images involved need to be resized a lot by Inquisit -- i.e. they have many more pixels than they end up occupying on the screen given their /size settings -- it's possible for it to look like thin borders aren't there. Make sure your images have an original resolution that's as close as possible to their eventual size on-screen in pixels. Also note that Inquisit never distorts the original image files aspect ratio, regardless of what you specify in the <picture> element's /size attribute. In other words, you may have chosen positions such that some of the images subtly overlap on-screen.

If you can take a look at the two attached files, the image stimulus that I am displaying are matrices which have different number of rows, therefore, Inquisit also changes the display of the image stimulus so that they are different sizes. 

I am having difficulties with displaying the images so that they have the same absolute size on the screen. Furthermore, the line borders as you can see are also missing.
Are there any suggestions of fixing these two problems?

Thanks.

Happy to take a look but the two screenshots you posted are of little use in isolation. Please provide some actually runnable example code and include the actual image files you are using with that code.

Hi, below are some of the code and attached are two different png files for the image stimulus that have different matrix sizes.

<item matrices>
/1 = "M1R1S36A7.png"
/2 = "M1R4S36A17.png"
/3 = "M2R1S36A15.png"
/4 = "M2R4S36A22.png"
/5 = "M3R2S36A18.png"
/6 = "M3R5S36A28.png"
/7 = "M4R2S36A36.png"
/8 = "M4R5S36A7.png"
/9 = "M5R3S36A4.png"
/10 = "M5R6S36A34.png"
/11 = "S6/M1R1S6A1.png"
/12 = "S6/M5R1S6A2.png"
/13 = "S6/M6R1S6A6.png"
/14 = "S6/M7R1S6A2.png"
/15 = "S6/M8R1S6A6.png"
</item>

<picture matrices>
/ items = matrices
/ size = (100%, 100%)
/ width = 50%
/ height = 100%
</picture>

<textbox t1q1>
/ caption = "Answer:"
/ position = (80%, 10%)
/ textboxsize = (15%, 5%)
/ required = true
/ mask = positiveinteger
/ range = (1, 36)
</textbox>

<block first_trial>
/ preinstructions = (instructions)
/ trials = [1 = t1page1; 2 = t1page2; 3 = t1page3]
</block>

<surveypage t1page1>
/ stimulusframes = [1 = noreplacenorepeat(picture.matrices)]
/ caption = "Enter the grid number which you think best completes the matrix"
/ questions = [1 = q1]
/ showquestionnumbers = false
/ itemfontstyle = ("Arial", 2.5%, false, false, false, false, 5, 1)
/ responsefontstyle = ("Arial", 2.5%, false, false, false, false, 5, 1)
/ nextbuttonposition = (80%, 35%)
/ showpagenumbers = false
/ recorddata = true
</surveypage>

<surveypage t1page2>
/ stimulusframes = [1 = noreplacenorepeat(picture.matrices)]
/ questions = [1 = q1]
/ showquestionnumbers = false
/ itemfontstyle = ("Arial", 2.5%, false, false, false, false, 5, 1)
/ responsefontstyle = ("Arial", 2.5%, false, false, false, false, 5, 1)
/ nextbuttonposition = (80%, 35%)
/ showpagenumbers = false
/ recorddata = true
</surveypage>

<surveypage t1page3>
/ stimulusframes = [1 = noreplacenorepeat(picture.matrices)]
/ questions = [1 = q1]
/ showquestionnumbers = false
/ itemfontstyle = ("Arial", 2.5%, false, false, false, false, 5, 1)
/ responsefontstyle = ("Arial", 2.5%, false, false, false, false, 5, 1)
/ nextbuttonposition = (80%, 35%)
/ showpagenumbers = false
/ recorddata = true
</surveypage>

Well, first off, those images have pretty large dimensions. They are 1667 x 1354 pixels for M1R1S6A1.png, and 1667 x 2438 pixels for M1R1S36A7.png respectively. If you display the images on a monitor that has fewer pixels and/or are not using the entire screen area to draw on (per the script's /canvasaspectratio setting, for example), the images will have to be scaled _down_ quite a bit. Moreover, the "borders" are extremely thin -- they have a width of exactly one pixel (out of 1667 pixels, out of 1354 pixels, and out of 2438 pixels respectively). There is no way to reliably preserve that faint border if the whole image -- with original dimensions of 1667 x 2438 pixels -- has to be squeezed down to, say, 985 x 1440 pixels as would be the case if you were using a fairly high-res 2560 x 1440 monitor. The lower the monitor resolution, the more drastically the images have to be squeezed, of course.

So, ultimately, what you should do is decrease the original images' resolutions, i.e. pick dimensions that will work reasonably well across a wide range of display resolutions. You should avoid situations where the images have to be either scaled down or scaled up too much. Also make sure that the image features that are important for your purposes aren't too faint (cf. the single pixel "borders" mentioned above).