Kdenlive/Manual/快速開工

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Revision as of 10:46, 1 April 2013 by Yurchor (talk | contribs) (Importing a new version from external source)

Quick Start

創建新專案

Kdenlive directory structure

首先,創建新(空)的目錄夾給我們專案使用. 我將稱它 quickstart-tutorial/ 在本次的教學之中.然後放上一些範例素材, 或從這裏下載:kdenlive-tutorial-videos-2011-avi.tar.bz2 (7 MB)[1], 然後將它們解壓縮。 例如. 放到本專案下的子目錄 quickstart-tutorial/Videos/ .

左邊的圖片顯示建議的目錄結構:每個專案有自己的目錄,將影片檔放在Videos 子目錄,聲音檔放在 Audio子目錄,等。(read more)

(從現在開始,本教學假設您使用範例影片,當然你也可以用其他的範例影片。)


New Project dialog

打開 Kdenlive 之後, 新建一個專案 (檔案 -> 新增).

選擇剛才新建的目錄夾(quickstart-tutorial/) ,然後選擇一個合適的專案描述檔。上面提供的影片是720p, 23.98 fps.[2] 假如您用自己的檔案並不清楚該用那一個, Kdenlive 在你載入第一個素材時將建議你一個合適的描述檔[3]


Adding clips

Project Tree: Adding video clips

Now that the project is ready, let’s start adding some clips (i.e. the ones you downloaded). This works via the Project Tree widget; a click on the Add Clip icon directly opens the file dialog, a click on the small arrow shows a list of additional clip types that can be added as well. Video clips, audio clips, images, and other Kdenlive projects can be added via the default Add Clip dialog.


Kdenlive 0.8 window with the tutorial files

After loading the clips, Kdenlive will look similar to this. On the top left there is the already known project tree. Right of it are the monitors that show video; The clip monitor displays video from the original clips, the project monitor shows how the output video will look, with all effects, transitions, etc. applied. The third, also very important, item is the timeline (below the monitors): This is the place where the video clips will be edited. There are two different types of tracks, Video and Audio. Video tracks can contain any kind of clip, audio tracks as well – but when dropping a video file to the audio track, only the audio will be used.


Saving a Kdenlive project

Let’s save the work via File -> Save. This saves our project, i.e. where we placed the clips on the timeline, which effects we applied, and so on. It can not be played.[4] The process of creating the final video is called Rendering.


Timeline

See also Timeline section of the manual

Now comes the actual editing. Project clips are combined to the final result on the timeline. They get there by drag and drop: Drag some Napoli (assuming you are using the files provided above, as in the rest of this quick start tutorial; If not, please make sure your screen is waterproof, and perhaps tomatoproof), and drop it onto the first track in the timeline.

First clips in the timeline

Since some cutlery is needed as well, drop the spoon on the first track as well. Then drag the Napoli to the beginning of the timeline (otherwise the rendered video would start with some seconds of plain black), and the Spoon right after the Napoli, such that it looks like in the image on the left. (Where I have zoomed in with Ctrl + Wheel.)


Timeline cursor

The result can already be previewed by pressing Space (or the Play button in the project monitor). You will see the Napoli directly followed by a Spoon. If the timeline cursor is not at the beginning, the project monitor will start playing somewhere in the middle; you can move it by dragging it either on the timeline ruler or in the project monitor. If you prefer keyboard shortcuts, Ctrl + Home does the same for the monitor that is activated. (Select the Project Monitor if it is not selected yet before using the shortcut.)


Resize marker

Since after eating comes playing, there is a Billard clip. Add it to the timeline as well. The first 1.5 seconds nothing happens in the clip, so it should perhaps be cut to avoid the video becoming boring. An easy way[5] for this is to move the timeline cursor to the desired position (i.e. the position where you want to cut the video), then drag the left border of the clip when the resize marker appears. It will snap in at the timeline cursor when you move close enough.


Overlapping clips

To add a transition between eating (the Spoon) and playing billard, the two clips need to overlap. To be precise: the second clip should be above or below the first one and end some frames after the second one begins. Zooming in until the ticks for single frames appear helps here; it also makes it easy to always have the same transition duration, like five frames in this case.

You can zoom in by either using the zoom slider at the bottom of the Kdenlive window, or with Ctrl + Mousewheel. Kdenlive will zoom to the timeline cursor, so first set it to the position which you want to see enlarged, then zoom in.


Transition marker

Now that the clips overlap, the transition can be added. This is done either by right-clicking on the upper clip and choosing Add Transition or, easier, by clicking the green triangle that appears when you hover the mouse over the lower right corner of the Spoon clip. The latter, by default, adds a dissolve transition, which is in this case the best idea anyway since the Spoon is not required for playing anyway.

The dissolve transitions fades the first clip into the second one. See also Transition section of the manual.


Let’s add the last clip, the Piano, now, and again apply a dissolve transition. When adding it on the first track of the timeline, you need to click on the new clip’s lower left edge to add the transition to the previous clip.



Effects

Effect List

The Piano can be colourized by adding an effect to it. Select the piano clip, then double-click the RGB Adjustment effect in the Effect List. If it is not visible, you can get it via View -> Effect List.


Once the effect has been added, its name will be added to the timeline clip. It will also be shown in the Effect Stack widget.


Effect Stack with RGB adjustment

To get a warm yellow-orange tone on the image, fitting the comfortable evening, blue needs to be reduced and red and green improved.

The values in the effect stack widget can be changed by using the slider (middle mouse button resets it to the default value), or by entering a value directly by double-clicking the number right to the slider.

Effects can also be added with the Add new effect icon (framed in the image on the left) in the Effect Stack; It always refers to the timeline clip that is currently selected. By unchecking the checkbox they are temporarily disabled (the settings remain though), this is e.g. useful for effects that require a lot of computing power, so they can be disabled when editing and enabled again for rendering.

For some effects, like the one used there, it is possible to add keyframes. The framed watch icon indicates this. Keyframes are used for changing effect parameters over time. In our clip this allows us to fade the piano’s colour from a warm evening colour to a cold night colour.


Keyframes for effects

After clicking the keyframe icon (the clock icon framed in the previous image), the Effect Stack widget will re-arrange. By default there will be two keyframes, one at the beginning of the timeline clip and one at the end. Move the timeline cursor to the end of the timeline clip, such that the project monitor actually shows the new colours when changing the parameters of the keyframe at the end.

Make sure the last keyframe is selected in the Effect Stack’s list. Then you are ready to flood the piano with a deep blue.

Moving the timeline cursor to the beginning of the project and playing it (with Space, or the Play button in the Project Monitor), the piano should now change the colour as desired.

Keyframing was the hardest part of this tutorial. If you managed to do it, you will master Kdenlive easily!

See also Effects section of the manual.


Music

Audio fadeout

Since the clips do not provide any audio, let’s search for some nice piece of music, on your local collection or on web pages like Jamendo. The audio clip should, after adding it, go to an audio track on the timeline.

The audio clip can be resized on the timeline the same way as video clips are. The cursor will snap in at the end of the project automatically. To add a fade out effect at the end of the audio clip (except if you found a file with exactly the right length) you can hover the top right (or left) edge of the timeline clip and drag the green disc to the position where fading out should start.[6]


Rendering

Rendering dialog

A few minutes left, and the project is finished! Click the Render button (or go to Project -> Render, or press Ctrl + Enter) to get the dialog shown on the left. Select the desired output file for our new video with all effects and transitions, choose MPEG4 (works nearly everywhere) and a bitrate of 2000k (the higher the bitrate, the larger the output file and the better the quality – but since the bitrate for the input clips was 2000k already, using a higher one would not improve quality and is therefore unnecessary), and press the Render to File button.


Rendering progress

After some seconds rendering will be finished, and your first Kdenlive project completed. Congratulations!


References and notes

  1. 假如你偏好 Theora (因為你覺得 Ogg 格式的影片常發生問題), 你可以從這裏下載 kdenlive-tutorial-videos-2011-ogv.tar.bz2.
  2. 720 是片的高度 , p 代表 增進式掃描 可對照 interlaced video, 而 fps 數字表示每秒鐘的影格數.
  3. Kdenlive 設定提供的組態, 在 Misc 這裏設定成 Check if first added clip matches project profile當第一個素材加入時檢查合適的專案描述檔
  4. To be correct, it can be played using melt yourproject.kdenlive, but this is not the way you would want to present your final video since it is (most likely) too slow. Additionally, it only works if melt is installed.
  5. Writing it this way suggests that there are several ways of cutting a clip. This is in fact true.
  6. This green disc is a shorthand for adding the effect Fade -> Fade out. Both ways lead to the same result.