In the past, film editing was done in a linear fashion, where the film was literally cut into long strips divided by scene and take, and then glued or taped back together to create a film in logical sequence. This was time-consuming, tedious and highly specialized work. While linear editing is still relevant today, there is a newer and more user-friendly system available for editors: nonlinear editing. Curious about what these systems can and can’t do and the pros and cons each system has? Well, let’s take a look…
Linear Video Editing Method
Linear video editing is a process of selecting, arranging and modifying images and sound in a pre-determined, ordered sequence – from start to finish. Linear editing is most commonly used when working with videotape. Unlike film, videotape cannot be physically cut into pieces to be spliced together to create a new order. Instead, the editor must dub or record each desired video clip onto a master tape.
For example, let’s say an editor has three source tapes; A, B and C and he decided that he would use tape C first, B second and A third. He would then start by cutting up tape C to the beginning of the clip he wants to use, then as he plays tape C, it would also be simultaneously recording the clip onto a master tape. When the desired clip from tape C is done, the recording is stopped. Then the whole process is repeated with tapes B and A.
Pros vs Cons
There are a couple of disadvantages one would come across when using the linear video editing method. First, it is not possible to insert or delete scenes from the master tape without re-copying all the subsequent scenes. As each piece of video clip must be laid down in real time, you would not be able to go back to make a change without re-editing everything after the change.
Secondly, because of the overdubbing that has to take place if you want to replace a current clip with a new one, the two clips must be of the exact same length. If the new clip is too short, the tail end of the old clip will still appear on the master tape. If it’s too long, then it’ll roll into the next scene. The solution is to either make the new clip fit to the current one, or rebuild the project from the edit to the end, both of which is not very pleasant. Meanwhile, all that overdubbing also causes the image quality to degrade.
However, linear editing still has some advantages:
It is simple and inexpensive. There are very few complications with formats, hardware conflicts, etc.
For some jobs linear editing is better. For example, if all you want to do is add two sections of video together, it is a lot quicker and easier to edit tape-to-tape than to capture and edit on a hard drive.
Learning linear editing skills increases your knowledge base and versatility. According to many professional editors, those who learn linear editing first tend to become better all-round editors.
Nonlinear Video Editing Method
The nonlinear video editing method is a way of random access editing, which means instant access to whatever clip you want, whenever you want it. So instead of going in a set order, you are able to work on any segment of the project at any time, in any order you want. In nonlinear video editing, the original source files are not lost or modified during editing. This is done through an edit decision list (EDL), which records the decisions of the editor and can also be interchanged with other editing tools. As such, many variations of the original source files can exit without needing to store many different copies, allowing for very flexible editing. It is also easy to change cuts and undo previous decisions simply by editing the EDL, without having to have the actual film data duplicated. Loss of video quality is also avoided due to not having to repeatedly re-encode the data when different effects are applied.
Nonlinear editing differs from linear editing in several ways.
First, video from the sources is recorded to the editing computer’s hard drive or RAID array prior to the edit session.
Next, rather than laying video to the recorder in sequential shots, the segments are assembled using a video editing software program. The segments can be moved around at will in a drag-and-drop fashion.
Transitions can be placed between the segments. Also, most of the video editing programs have some sort of CG or character generator feature built in for lower-thirds or titles.
The work-in-progress can be viewed at any time during the edit in real time. Once the edit is complete, it is finally laid to video.
Non-linear video editing removes the need to lay down video in real time. It also allows the individual doing the editing to make changes at any point without affecting the rest of the edit.
Pros vs Cons
There are many advantages a nonlinear video editing system presents. First, it allows you access to any frame, scene, or even groups of scenes at any time. Also, as the original video footage is kept intact when editing, you are able to return to the original take whenever you like. Secondly, nonlinear video editing systems offers the flexibility of editing. You can change your mind a hundred times over and changes can also be made a hundred times over without having to start all over again with each change. Thirdly, it is also possible to edit both standard definition (SD) and high definition (HD) broadcast quality videos very quickly on normal PCs which do not have the power to do the full processing of the huge full quality high resolution data in real-time.
The biggest downside to nonlinear video editing is the cost. While the dedicated hardware and software doesn’t cost much, the computers and hard drives do, from two to five times more than the gear. As such, the average price for a basic nonlinear video editing package can come in between $5,000 and $10,000. For stand-alone systems that approach broadcast quality, the amount you pay may be twice that. However, as the nonlinear technology pushes forward, count on big gains in digital video storage and compression, as well as lower prices on computers and hard disks in the very near future.
Making the Choice
Now that you know the differences between linear and nonlinear editing systems, you are now equipped to make a choice between the two for your editing needs. But keep this in mind – on certain types of production, a linear editing system may actually be more efficient and nonlinear may reign supreme on other types of productions; so don’t write off either one. Whatever you do, just make sure to do your homework before deciding.