pxt-calliope/docs/reference/images/scroll-image.md

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# Scroll Image
Scroll (slide) an [image](/reference/images/image) (picture) from one
side to the other of the [LED screen](/device/screen).
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### Parameters
* ``offset`` is a [number](/reference/types/number) that means
how many LEDs to scroll at a time, from right to left or
left to right. If you use a positive number like `2`, the image
will scroll from the right side of the screen to the left.
If you use a negative number like `-2`, the image will scroll
in the other direction. If you use `5` or `-5`, the image
will scroll one **frame** at a time. (A frame is a part of the
image. It is a square with five LEDs on a side). This is
useful for **animation**.
* ``interval (ms)`` is a [number](/reference/types/number) that means
how many milliseconds to wait before scrolling the amount that
``offset`` says. (1000 milliseconds is one second.) The bigger you
make this number, the slower the image will scroll.
### Example
This program scrolls an image of two arrows five LEDs at a time,
with a pause of 200 milliseconds between each time it scrolls.
Because each frame is five LEDs wide, that means this program
will look like it's animating one arrow flipping and flopping.
Of course, you can use any two frames you want instead.
```blocks
let arrows = images.createBigImage(`
. . # . . . . # . .
. # # # . . . # . .
# . # . # # . # . #
. . # . . . # # # .
. . # . . . . # . .
`);
basic.forever(() => {
arrows.scrollImage(5, 200);
});
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```
### See also
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[show image](/reference/images/show-image), [image](/reference/images/image), [create image](/reference/images/create-image), [show animation](/reference/basic/show-animation)
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