file formats. many different file formats we have seen that photoplus can export a picture into...

File formats

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

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

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

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

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

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

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

Layer control• Look at the layer tab

Layer control• Look at the layer tab• Each layer has a little

eye beside it• If the eye is open, the

layer is visible

Layer control• Look at the layer tab• Each layer has a little

eye beside it• If the eye is open, the

layer is visible

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

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

Suppose we close the eye for Layer 4

Suppose we close the eye for Layer 4

Suppose we close the eye for Layer 4

• The picnic basket becomes invisible

Suppose we open the eye again

Suppose we open the eye again

• The picnic basket becomes visible again

Suppose we close the eye for Layer 5

Suppose we close the eye for Layer 5

Suppose we close the eye for Layer 5

• The boy becomes invisible

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

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

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

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

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

In this picture, the top layer has a transparent background

In this picture, the top layer has a transparent background

• So the bottom layer, and its white background, show through

In this picture, the top layer has a transparent background

• So the bottom layer, and its white background, show through

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

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

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

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

So, back to that motivating example

• The desired effect was achieved by using two layers

So, back to that motivating example

• The desired effect was achieved by using two layers

The two layers

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

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

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

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