GIMP/C2/Rotating-And-Cropping-An-Image/English-timed

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Time Narration
00:22 Welcome to the spoken tutorial of GIMP.
00:24 Before I start editing this image, I want to tell you in brief about using RAW for your real photography.
00:33 If I had shot this image in JPEG, I would have had 256 steps of brightness for encoding it.
00:42 You can see it’s nearly black and white, a bit bluish greenish tint and basically it’s only gray.
00:52 And with JPEG, you have 256 different values of gray -
01:00 zero for black and 255 for white.
01:05 And in this image there is no white and only a bit black.
01:11 So only a small space of this room is used.
01:16 I’ll show you how much later.
01:19 I had shot this image in RAW and my camera stores RAW images in 12 bit data format.
01:27 This is the image I have got out of the RAW converter after spreading the values and here I have 256 different values of gray and now I can start to edit the image.
01:42 In this image, there are more details saved as compared to the first one.
01:47 This is the first image I remember and this one I have got after conversion.
01:54 The second image is a good base for doing post processing which results in a picture which has the mood of the 1st image but looks better.
02:06 Now I have opened the two images in the GIMP. So let’s have a look at the histogram of the 2 images.
02:14 The histogram is hidden in the image dialog.
02:17 But we have 3 different ways of reaching the image dialog, first way is on the tool bar.
02:33 Second way is to click on Access the image menu here and click on dialogs.
02:40 And the third way is simply right click into the image, then Dialog and Histogram.
02:48 Here’s the histogram of the first image.
02:51 Make it a bit bigger and here you see the distribution of different pixels of the different colors in the image.
02:59 Digital image is similar to painting by numbers.
03:03 When you zoom into the image, you see a lot of little tiles and each of these tiles has a different color which is called as a 'pixel'.
03:14 And each color is defined by a value and I can show you these values here with the help of Color Picker.
03:26 When I use colour picker, I get the values for red, green & blue.
03:32 In this image, the value of red is a bit less than green and blue.
03:38 Green and blue have nearly and exactly the same value.
03:43 Painting by numbers is digital photography.
03:46 In this image here, I have numbers from 0 to 255 and we have a really dark part here but I don’t think it will make into the final image.
04:00 I think, the real part of the image starts here around 80 and the brightest part of the image is here at around 200.
04:10 So, we have room from 0 to 256, but we only use 120 which is less than half of data which we could use.
04:23 And because of that, a lot of information of the image is lost here.
04:29 Let’s have a look at the histogram of the second image.
04:33 As we can see here, there is more data in this histogram as compared to first one but the form of the curve is identical.
04:45 You compare these two histograms.
04:51 Details in the 2nd image is spread out. So the problem I have to solve here is to make the 2nd image compressed like the 1st one.
05:01 But it should have a bit more of details and it should have a bit more of contrast like this one in the first image.
05:11 Before I start working with this image, I want to show you a thing that I found out about the GIMP user interface while recording the last tutorial.
05:23 When you press tab into the image window, the tool-box here vanishes and helps me in getting the image as big as possible and I can switch the tool-box 'On' and 'Off' as per my requirement.
05:41 So I can see it better what I am doing here and you can also see it better.
05:46 Before I start editing the image, I have to change some settings.
05:52 So, I go to File, Preference and here I go to Window Management and choose the option here,
06:03 Keep above for the toolbox and Keep above for the docks and leave the rest of options as it is.
06:11 After I press OK, the GIMP works as advertised.
06:17 I can select the tools from the tool box and get all options of the tool I have selected.
06:25 I can click back into the image and use tab to switch the tool box on and off.
06:33 The first thing to do is to check if the image is leveled.
06:37 In this image, there are no reliable man made structures here. So I can’t use the grid method to check if the image is straight .
06:47 The surface of the water is a very good clue.
06:50 But we don’t see the horizon here and the streaks on the water are also a bit misleading.
06:57 This, here, is not the horizon but just a curve in the river.
07:02 So, I don’t have a real clue where to set a ruler and check the horizon.
07:08 I just have to rely on my eye which I don’t think is the worst way to do something in photography.
07:16 Now, I select the Rotate tool and I choose Normal Forward instead of Corrective Backward and I set in Preview as Image and not the Grid.
07:30 Ok, click into the image.
07:38 Here, in the center, there is a point called "center of rotation" and around that point the image will be rotated.
07:46 And here is the dialog where we can set the Angle about which we want to rotate the image.
07:52 Here I have a slider which can help me in rotating the image but you can see it is difficult to handle and I don’t think I have to tilt the image this much.
08:05 So let’s go back to zero here and now I just use the style here to rotate the image.
08:14 I think the image is bit tilted towards the right. So I have to rotate the image to the left i.e. counter-clockwise, so I have to get here negative values.
08:29 So, I keep on changing the Angle till I get the correct and straight image.
08:36 So, I set the angle for "-0.25°".
08:43 Pull this window in and click on rotate and wait for the result of this operation.
08:50 Next step: "cropping".
08:54 In the image, I want to have the ship, the water and these birds here.
09:02 And I don’t want to have in the image is this grass here, this part here and I m really not sure if I want to have this bank of the river in my image.
09:16 And I think I will crop this part of image because later I want to have the darkest part of the image.
09:24 i.e the birds here, the ship and then the trees, the bank behind the ship, and lastly the water and sky.
09:35 And this part of the image is too dark.
09:39 I want to zoom into this part of the image as I want to include as much as possible the part of the river but nothing of the bank.
09:49 So, I zoom into the part of the image here by pressing the hot key Z.
10:00 Here’s another bird flying.
10:02 So, I go to the left side and I pull over the ruler close to the bank and leave it here.
10:09 And press Shift + ctrl + E which brings me back to the image.
10:15 Now I have to select the Crop tool and set some options in it.
10:20 I want the Fixed aspect ratio 2:1.
10:29 And in Preview, I set Rule of thirds for little bit of help which will provide me some helpful lines.
10:37 Let me see, what all is included here.
10:41 Here, it is a group of birds and single bird appears here.
10:47 Now you can click the rulers away.
10:51 On the lower part of image, there is water but I think it’s not enough water in it and too much sky is included.
11:01 I can lose this single bird up here because I want this group of birds to stay in the image.
11:09 Now I simply pull this down and I think this looks quite nice.
11:14 To check my work, I select Rule of thirds.
11:19 My eye isn’t so bad because I divided the image into 3 different parts i.e the water, the trees and the sky.
11:30 The ship is one of the point of interest.
11:34 This group of birds is second point of interest and this one is nice 1/9th of the image.
11:42 I think this will work; so I click into the image to crop.
11:49 Press tab and shift + ctrl +E to enlarge the image.
11:55 I think we have started very well with the cropping of the image and what else to do with this image, I will show you in the next tutorial.
12:05 Before I say good bye, I should save the image which I should have done much earlier.
12:12 I save the image as Fog.xcf and ‘xcf’ is the extension of GIMP’s own file format and it contains lot of helpful information of layers and undo information and much more from the GIMP.
12:29 I would like to hear from you.
12:32 Tell me what you liked, what I could have made better by mailing me on to info@meetthegimp.org.
12:42 More information is available at http://meetthegimp.org
12:47 This is Hemant Waidande, dubbing for the Spoken Tutorial project .

Contributors and Content Editors

Kavita salve, Minal, PoojaMoolya, Sandhya.np14