1. File formats

2. Many different file formats We have seen that PhotoPlus can export a picture into a.jpg file This is only one of many different digital formats that are used for storing pictures Other formats you may have come across include.gif,.bmp,.png, … PhotoPlus also supports a format,.spp, which has many useful features that are not supported by any of the above formats One of these useful features is –spp files allow a picture to have multiple layers

3. A picture with multiple layers This PhotoPlus window shows a picture which has two layers

4. A picture with multiple layers This PhotoPlus window shows a picture which has two layers We can see this by looking at the bottom right corner

5. A picture with multiple layers This PhotoPlus window shows a picture which has two layers We can see this by looking at the bottom right corner This corner can show various tabs

6. A picture with multiple layers This PhotoPlus window shows a picture which has two layers We can see this by looking at the bottom right corner This corner can show various tabs –Currently, the Layers tab is open –It shows two layers –Their names are Layer 4 and Layer 5 but these names are purely coincidental They could have been called Layer 1 and Layer 2

7. A picture with multiple layers This PhotoPlus window shows a picture which has two layers We can see this by looking at the bottom right corner This corner can show various tabs –Currently, the Layers tab is open –It shows two layers –Their names are Layer 4 and Layer 5 but these names are purely coincidental They could have been called Layer 1 and Layer 2

8. A picture with multiple layers This PhotoPlus window shows a picture which has two layers We can see this by looking at the bottom right corner This corner can show various tabs –Currently, the Layers tab is open –It shows two layers –Their names are Layer 4 and Layer 5 but these names are purely coincidental They could have been called Layer 1 and Layer 2

9. Layer control Look at the layer tab

10. Layer control Look at the layer tab Each layer has a little eye beside it If the eye is open, the layer is visible

11. Layer control Look at the layer tab Each layer has a little eye beside it If the eye is open, the layer is visible

12. Layer control Look at the layer tab Each layer has a little eye beside it If the eye is open, the layer is visible If we click on an eye, it closes –and the corresponding layer become invisible

13. When both layers are visible, we see a boy and a picnic basket

14. Suppose we close the eye for Layer 4

16. The picnic basket becomes invisible

17. Suppose we open the eye again

18. The picnic basket becomes visible again

19. Suppose we close the eye for Layer 5

21. The boy becomes invisible

22. The two layers have different backgrounds The layer containing the boy has an opaque background –coloured white The layer containing the basket has a transparent background

23. The two layers have different backgrounds The layer containing the boy has an opaque background –coloured white The layer containing the basket has a transparent background

24. The two layers have different backgrounds The layer containing the boy has an opaque background –coloured white The layer containing the basket has a transparent background

25. The two layers have different backgrounds The layer containing the boy has an opaque background –coloured white The layer containing the basket has a transparent background

26. Backgrounds and layer ordering If the background of a layer is transparent, the content of the layer(s) below it will show through If the background of a layer is opaque, the content of the layer(s) below it will not show through

27. In this picture, the top layer has a transparent background

28. So the bottom layer, and its white background, show through

29. In this picture, the top layer has a transparent background So the bottom layer, and its white background, show through

30. We can drag a layer up Suppose we want to drag Layer 5 up to the top

31. We can drag a layer up Suppose we want to drag Layer 5 up to the top Click on it, so that it is highlighted

32. We can drag a layer up Suppose we want to drag Layer 5 up to the top Click on it, so that it is highlighted And then drag it up with the mouse

33. We can drag a layer up Suppose we want to drag Layer 5 up to the top Click on it, so that it is highlighted And then drag it up with the mouse Notice that the basket no longer shows through

34. So, back to that motivating example The desired effect was achieved by using two layers

35. So, back to that motivating example The desired effect was achieved by using two layers

36. The two layers

37. The transparency/opacity of the two layers The top layer contains the boy –And has a transparent background The bottom layer contains the picture of the girls and picnic basket

38. The transparency/opacity of the two layers The top layer contains the boy –And has a transparent background The bottom layer contains the picture of the girls and picnic basket

39. The transparency/opacity of the two layers The top layer contains the boy –And has a transparent background The bottom layer contains the picture of the girls and picnic basket

40. The transparency/opacity of the two layers The top layer contains the boy –And has a transparent background The bottom layer contains the picture of the girls and picnic basket