Doc:Tutorials/Sequencer/Examples 2

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[edit] Working with Blender for Video Editing

This section covers the workflow of the video editor, providing numerous examples of practically using the tools described in the previous sections. While editing can occur in any order, in the real world it begins based on what footage has been shot, called "in the can".

Lots of times, footage is shot out of sequence. For example, they may shoot the fight scene first, then the introduction, then the thrilling climax, and titles added just before release. This style of shooting is motivational, and you have some exciting dailies to show the producer and to lock in total funding, but is hard on the actors to give a good performance, and hard on the editor because he can't tell the whole story. It's analogous to writing a book by starting to write chapter 13 first.

This section assumes that all footage has been shot, and we want to edit the video in sequence to produce a post-production pre-audio copy.

This section also assumes you will be producing an animation, and that the audio track will be recorded or synched after you are done, so you don't have to make markers or insert synch frames into your video.

[edit] Cut Rollup/Rolldown

The Director says "lights, camera, action" to turn on the lights, start the camera rolling, and to get the actors in gear to do their thang. In between camera and action, a clapper claps to enable us to sync audio later with the video. After the scene is complete, he says "cut" which stops the action and camera. When you get the raw footage uploaded, you need to chunk it out into clips that can be reviewed, and the best chosen. The part where the camera starts up to the clap is the rollup and is useless. Any filming from the time he says cut to the end of filming is rolldown garbage.

Everything from the start of the raw footage up to the clapper making the clap can be cut. To cut rollup, simply position your cursor to the frame where the clapper bar meets the clapper as seen in the Sequence window set on Image display (the strip must be selected). Back up one frame rightarrow and press K to cut, and confirm. The strip is cut in two; just like using a bench and a razor. Select the rollup and press X to delete it. Grab and slide the remainder to frame 1.

At the end, everything filmed after and including the word "cut" can be cut, leaving a middle segment that may contain multiple partial or complete takes. To cut rolldown, find where he says "cut", and Kut and X delete the tail (unless there's another scene and/or take left). Sometimes the director will forget to say cut, and the camera keeps rolling, so you have to cut it for him by looking at it and seeing when the actors finish. Cut from there to the next clap (or end of footage), but move up the footage to a higher channel. It will be kept for review by the director, but won't be shown since the video beneath it will be shown instead.

[edit] Cut out Flubs

For example, an actor may get halfway through their lines, flub the last word of the third sentence, do an "ahblahyadayada" to get the marbles out of their mouth, and start over with the start of the third sentence without prompting. In this case, the middle flub needs to be cut out of the middle (more often than not, they will have moved their head or background has changed resulting in a discontinuity, and the footage will have to be tossed. However, using the offset and displace nodes and transform sfx, it may be possible to salvage it and splice the two). Cutting without a clap is a little dangerous, since the audio engineer is going to have to cut out the exact same flub. In this case, keep a record the actual number of frames cut by moving the cut to a higher channel, and the audio engineer can calculate how many milliseconds to cut as well.

For this reason, when you cut the flub, just move the flub up a channel or two, and slide the remainder underneath it. This way the flub is still available for a gag reel, and is available for you to review when the audio engineer asks how many frames were cut because he lost the tracking sheet.

You may also cut out dead time in this manner; cutting straight to the action (from the clap to the start of useable footage) while preserving frames for later review or use by other people.

[edit] Save Scrubs

I hope the previous sections show you how you can use Blender as a full featured video editing system. Ok, time to save:

• In the Buttons window, Output panel, change the output filename to reflect the scene and take number (shown on the clapper). You may want to disable extensions.
• In the Timeline window header, set the start and end frames for the take
• Scrub it
• Enable Do Sequence in the Anim panel, and set whatever your format is needed
• Click Anim and that clip will be saved.

Let's move on to using Blender to composite the action footage into a movie.

[edit] Video Conversion

Many times input video will be in different formats (avi jpeg and quicktime) and/or different sizes (resolutions) and/or different frame rates. As we have seen, Blender automatically converts stills (images and image sequences) into video when Added. Regardless of the input, Blender renders a single output in the format (codec, resolution, framerate) specified. This means that you can Add->Movie and pick a QuickTime movie and load it into the VSE. If you specify "Avi Jpeg" as your output format (in the Buttons window, Scene Render context, Format panel), and "Do Sequence", Blender will convert the QuickTime video to a compressed .avi file which can be played in Windows Media Player.

Images or video are automatically scaled or cropped to fit within the resolution window specified in that output format panel. If they are smaller than the output resolution, they are centered in the video (unless offset by the Transform effect).

Video of differing frame rates can easily be mixed and matched. With regard to frame rate, video is imported on frame-by-frame basis based on its run-time. If a 10 second video that was encoded at 24 frames per second is loaded, 240 frames will be loaded in, even if your output is, say, 30 frames per second. This means that your exported video sequence may run faster or slower than input. In this example, the imported video will be export to run for a duration of 8 seconds (240 frames / 30 frames per second = 8 seconds) instead of 10 seconds. If you want to correct this, select the segment and use the Speed Control effect, specifying a factor of 24 / 30 = 0.80, and the segement will be run in slight slow motion relative to the 30 fps you wanted. You will have to extend the video strip to end two seconds later (to fill up the gap) by right-clicking and grabbing the end frame, and dragging it to the right.

[edit] Overlay Text

In addition to being able to stamp common tracking information on the render, you may want to overlay some comments on top as well, such as a title, or questions for the director on animation, or to call attention to a material or lighting choice.

To do so, create a new scene and in a 3D window, switch to camera view. In that view, add a text object, and edit it to be your comment or import a text file. Position it roughly where you want it. In the VSE, add that comment scene as a scene strip, and AlphaOver it on top of the base video. Use the Premultiply option on the Comment strip so that it does not affect the colors of the base image.

Redirects to fix

• Manual/Sequence Plugins → Doc:Manual/Sequencer/Effects/Plugins
• Manual/Text → Doc:Manual/Modelling/Text
• Manual/Video Sequence FileOrg → Doc:Tutorials/Sequencer/Suggested files organization
• Reference/Panels/Scene/Render/Stamp → Doc:Reference/Panels/Scene/Render/Stamp