GIMP/C2/Selecting-Sections-Part-1/English

Time	Narration
00:23	Welcome to the tutorial of Meet The GIMP. My name is Rolf Steinort and i am recording this in Bremen,Northern Germany.
00:31	Lets start todays tutorial with this image. Today I'll work with this image only to use it as an example.
00:44	Before we start to work with selection, I think you should understand a bit about what selections really are.
00:57	This square is a selection and this part is outside of the selection. These moving lines here are the border of the selection.
1:15	The GIMP people call a selection as a channel. A channel like red, green or blue or an alpha channel which controls the transperancy. Outside of the selection, the value of this channel is zero. And inside its 255 ,and between them is the border, and between them there can be values lower than 255 and higher than zero. So changing a selection or making a selection is changing some numbers.
1:55	And now lets have a look at how to make a selection.
2:01	For de-selecting a selection there are 2ways. 1st way is, go to Select and None. You also use the key combination of Shift + Ctr l+ A and get rid of a selection. Now select, the Rectangle Select Tool. And look into the options dialog.
2:33	On top there are four choices. The 1st one is replace the current selection. So I select different area here, and you can see that when I select a new area, the old selection is deleted.
2:52	The 2nd option is add to the current selection. By selecting that option, I can select different areas in the image and get a quite complicated selection. And if I go to my colour tabs and just pull the colour over to the selection, you can see, all the selected areas are filled with that colour and the area which is selected and not connected is also filled.
3:38	So adding something to a selection holds every selection as one, even if there’s no connection between the parts of the selection.
3:56	Its a bit complicated. Press Ctrl + Z to undo the filling. And shift + Ctrl + A to de-select everything. And back to my options dialog.
4:09	Now select a square here and select Subtract from the Current Selection. I Select this area but nothing happens. But when I select these area you can see that the edge is cut out. You can see that the frame of selection stays there and when I move it , changes can be made.
4:46	So the last selection you made can be change until you click into another palce to get a new selection, you can change your work all the time.
5:06	Now the last option is Intersect with the current selection. Lets try that.
5:16	I select a rectangle here and the area outside it is not selected and selections which were done before are deleted. And only selection in this rectangle is kept. I can also modify this rectangle until I have the area selected that I wanted.
5:48	So now we have covered four modes i.e. Replace, Add, Subtract and Intersect.
6:02	You can replace a selection by just clicking. Adding can be done by Click and Shift. So lets try that, I press the shift key and then by clicking I start adding new selections. And when I press the shift key and mouse key, a plus sign appears.
6:35	Now if I want to subtract the selection, I can press the ctrl key and now I press the mouse key and start to move you can see a minus sign. So now I can substract the selection.
6:58	And for intersetion, Shift + Ctrl should be pressed together and then select an area for intersecting.
7:22	If you memorize these key combinations you can select the area faster. And the same key are used by the other selection tool. So you'll just have to learn them only once.
7:44	Shift + Ctrl+ A, disable all the selections and brings back to my normal mode and now let's start with other stuff here.
7:56	Next option is Feather Edges, and when it you get another option here as Radius Count. So I increase it a bit and select an area. Now you can see here, there is rounded corner. I don’t want rounded corners here. Just to show you what has happened i'll filling this with black and I zoom into the image.
8:39	You can see here is a black colour in the middle and it fades out near the border and these margin ends are running in between the real black and the original image and here is the value of selection channel is 128.
9:11	So the half black colour fade's inside the selection and half outside. The margin ends is only the real border of your selection when you have a hard selection.
9:38	Feather edges is a nice option to get smooth selections. With the feather selection you get a less sharp seen and it is easier that way.
10:03	Technically minded people call feather selection as Gaussian blur and the radius I selected here is the radius of the Gaussian Blur.
10:22	The next option is Rounded Corners. It’s a rectangle with rounded corner and you can set the radius of the rounded corners. Here is the round part and these margins are the straight parts.
10:49	Here is the next option Antialiasing. This option sets the corner painting. I just fill this selection with black and now I go back to my selection tool and i de-select antialiasing and make another selection and fill this also with black.
11:30	So select the zoom tool and deselect all selections with Shift + Ctrl + A and zoom into this area. And here the edge is without antialiasing and it is either filled with black or not filled with black. And here you can see the stair of grays.
12:03	Here you can see the smooth corner without jaggis, and that’s called Antialiasing. This selection does not have a rounded corner but it's series of steps.
12:25	And when I go back to 100% zoom, I can see here are jaggies and its not smooth but here it are smooth corners and you can easily try it for yourself.
12:56	So if you want to have smooth corners then select Antialiasing. And if you want to have these gray tones in here then de-select that option.
13:19	So I select that option and there is a sub option called Expand From Centre and start working with it.
13:45	So I place a point here and I start pulling my selection from here and you see it grow from that point and this point is always in the middle of the selection. When I deselect that option I can pull selection here and the position of the corner changes according to my selection.
14:19	There is a key code for this. When I click at this point and press ctrl and I have a selection from centre and the selection expands from centre. And when I release the ctrl key, the selection vanishes.
14:55	When I press the Ctrl key before I press the mouse button, I can substract a selection and but when I first press the mouse key and then the Ctrl key I get selection from centre. The next option here is Fixed Aspect Ratio and I can have here pre-selected aspect ratio as 1 by 1 and when I draw it will always be a square.
15:52	I can select here 2 by 3 and I always get a selection in 2 by 3 ratio and switching to 3 by 2 gives such a selection in landscape mode.
16:15	There is another way to create a perfect square. I start the selection at this point and pull and then press shift. And now the fixed aspect ratio is selected with pre-selected value here.
16:43	And this is a fast way, so I can select areas with aspect ratios that I want and by just pressing shift.
17:00	The next option is highlight and when I use that, the area that is not selected is gray and all the area that is selected is white. And this concerns only the current selection so lets de-select it and look at other options. Here you can set these values by hand and if you click on fix here, then I can't change the size of the selection.But if I want to have set width two pixels less and height one pixel more so it fine tunes the selection.
17:51	I can move the selection a little bit to the right by increasing the value of X which is the point of origin. An when I click on fix, I can move the whole selection. So the ‘X’ and ‘Y’ value is the point of origin of this left top point and with fix button I can block the movement.
18:24	The next option is the guides. I can select a Centre Line which shows me where the middle point of the selection is. I can have the Rule Of Thirds, which is used for the graphic work or I can have the Golden Sections which is similar to the Rule Of Thirds.
19:00	On the bottom is Auto Shrink Selection and Shrink Merged. Auto Shrink Selection is not very useful. But Shrink Merged is an option which if selected, the algorithm looks at the all the layers, and if de-selected only the layer that you are working on is taken into consideration.
19:42	Before having a recap of these options we'll talk about Ellipse Selection. So de-select all the selections by pressing Shift+ctrl+A. On top you get the same options like Replace current selection, Add to the selection with Shift key before clicking and Subtract with Ctrl key before clicking and Intersect with Shift and Ctrl key before clicking.
20:20	Antialiasing is again for smooth edges. It is more important with ellipse then with rectangles because ellipse are always round.
20:34	Feather edges the same option as in rectangle. When I fill it with black and you can see a smooth gradient between black and white and these margin ends are in between black and white.
21:12	Expand from centre also works the same with the Ctrl key after clicking the mouse button.
21:26	Fixed aspect ratio is also the same, after clicking the mouse button you get a perfect circle with aspect ratio 1 by 1. Now let come to the last tool I want to show you for today and thats the Free Select tool.
21:50	When I select that tool I see the same options here and also the keys work the same for Add, Replace, Subtract and Intersect. It has only 2 further option i.e Antialiasing and feather edges with some functions. Here I get the radius of the circle and i de-select it now.
22:21	I select this lower part of the leaf to show you as example. And I click into the image where I want to start the selection and draw a line and follow the border of the leaf.
23:04	So now I have selected this area. I zoom into the image to do fine tuning. And in my selection dialog I select Add To The Current Selection and start adjusting the selection.
23:41	The algorithm looks for the shortest way to the point where you started the selection. For making the selection easy I can use a Quick Mask.
24:02	On the bottom left corner is the option, Toggle Quick Mask and I toggle that and you can see now my whole image is red.
24:14	It is a bit confusing option because the area which I have selected and the area which is not selected is shown in red. So I go to the toggle and right clicking on it gives me Configure, Colour and Opacity and here I can select a color so i set it to blue.
22:43	Now the area which is selected is Red and all the area is blue. And now I select a pen and start painting the selected area but before that I change the foreground and background with the key ’X’. And now I start to paint.
25:23	And when I over paint the border I can paint with the background colour.
25:36	For painting I should select the right size of the brush.
25:59	And when I untoggle the mask, you can see here is the mistake in selection and here also. So I select the toggle and correct the mistakes.
26:20	Fixed.
26:25	So the Quick Mask is an easy way to get a complicated selection right. You can use the quick selection as a tool.
26:46	You can change the opacity of the mask and now you can hardly see the parts which is not selected. 50% opacity is the right amount in most of the cases.
27:19	You can choose a colour of your choice for the unselected areas.
27:28	There is another option here called mask selected areas. It has just the opposite effect of the quick mask. So now the selected area is painted blue and this looks better in this case here. And when you de-select the quick mask, you can see your selection.
28:00	So now lets pretend that I have made a perfect selection here and I want to save the selection for the next time to work and dont want to loose it.
28:22	Just go to Select and Save to Channel because selections are basically channels.
28:38	I save it as Mask 1 and it will be stored with the ’XCF’ file. So now I can de-select everything with Shift + Ctrl + A. Select another part, and when I go back to my selection here and I can add to selection or subtract from selection or even intersect with selection and my selection is back here.
29:16	So if you want to save that,just go to select and save to channel. Good Bye.
29:28	This is Hemant Waidande dubbing for the Spoken Tutorial Project.

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