Non Linear Editing Primer

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This page is designed to both educate you about non linear editing (NLE), as well as help you pick out the NLE system that is best for you. Although none of our cards are “broadcast” or commercial quality, you will be amazed at the spectacular videos you can create, and the remarkable picture quality of this new technology. Best of all, you can now get a starting NLE system that will work great using a typical home multimedia computer.

First lets start with the easy answers:

Yes, you can edit video using your computer.

Yes, the video can look as good as the original footage.

Yes, you can add incredible effects, transitions and titles.

No, you don’t need to invest $5,000 or more.

No, you don’t have to be a computer genius to install it.

No, you don’t have to have a super powerful computer.

Now that we got that out of the way, let’s find out what Non Linear Editing is all about and what you really need to get going. By the time you finish this page you will have a good background and understanding of the technology. Hopefully, if I did my job right, you will also be left with a burning desire to start doing it!!

Before we begin to discuss Non Linear Editing (NLE), let’s go over what good old fashioned Linear editing is all about.

Linear Editing

Most of us are familiar with linear editing. The simplest form of linear editing is called assemble editing or deck to deck. This is when you copy only the “good” parts of a tape over to a new tape. Assemble editing systems often include titlers (character generators) or special effects generators to make the videos more fun to watch. A/B roll editing is when we edit from two or more video sources. An A/B roll system often includes a digital mixer, to let us cut, fade, dissolve and wipe from source A to source B. Insert editing is when we splice in a different scene, or video only, into the middle of an existing video tape. Only very expensive, high end editing decks are capable of insert editing.

Today, linear editing means deck to deck. The quality of your linear editing is dependent on the editing capabilities of your decks. For the best results you need special editing decks with flying erase heads, special editing jacks, pre-roll and time codes. These decks often cost $1000 or more.

Non Linear Editing

When we use the term NLE, we mean editing video from your hard drive. NLE requires two things: editing software and a video capture card to get the video into your computer. Once the video clips are digitized and on your hard drive they can be assembled in any order, with the drag of a mouse, much like moving around sentences in a word processing program.

Non Linear Editing software is timeline based. You start by selecting the in and out points of your scene. Remember, that since everything is digital, we can get frame accurate edit points every time! Each scene is then placed on the timeline. You can lay down more then one track of video and audio onto your timeline. If you want to set your video to music, you start by placing the captured sound file onto the timeline. Next you select and arrange all of your video scenes. You can move scenes and clips around in your video just by dragging them with your mouse. It really is that easy!

The best part about NLE is the effects. Since the video is in digital form, we don’t have to worry about time base correctors and frame synchronizers. Our effects are only limited by our own imagination and the software we choose to use. We can add special filters to clean up and restore picture quality, or to place ripples or swirls in the video. We can create awesome transitions between scenes such as page turns, flips, roll ups, and breakaways, plus the standard dissolves and wipes.

When it comes to titling and graphics, NLE lets you go crazy. You can use any Windows true type font, so foreign languages are no problem at all. Want to add a logo or computer graphic you designed onto your video, its a piece of cake. In fact, we can make it fly, bounce, or spin onto the video. Of course all our titles and graphics can be superimposed and mixed with our video.

You can also add cool plug-ins to your NLE software to create create awesome 3D transitions and effects, like having the video spin into a ball or having moving video on all sides of a rotating cube!! You can morph one image into another, just like in commercials and music videos!

You can even add multiple titles, filters and effects onto the same scene. The power of NLE is truly incredible. Now every videographer can create videos that look and feel like network productions. The video you can create using our video capture cards and software will have your audience cheering, with everyone wanting to see more and asking how you did it.

While it is the video editing software that lets you actually create and edit the video, it is the video capture card that determines the quality of your video.

Video Capture

Our video capture cards use various compression methods, called CODECs (COmpression/DECompression), to digitize and pack the video onto your hard drive. It is very important that you select the correct compression method to support your final video production. In today’s world of digital videography it is important to realize that there is much more then old fashion video tape to deliver your content.

1.MJPEG

If you want to edit video and go back out to video tape, MJPEG is the best, and most popular, technology currently available. Most of our cards use MJPEG. MJPEG is intended for creating high quality non linear editing with output back to tape. It is considered a “lossy” CODEC, so the lower the compression, the larger the file size, and the higher the video quality. 640×480 is considered to be full screen capture. This results in the best quality video. MJPEG cards often support 1/2 or 1/4 screen capture as well. These formats are good for multimedia or VHS editing because you get more video per gig. The downside of these smaller capture sizes is that the card ends up having to recreate the missing info so you can end up with artifacts and blurred colors.

The big decision you have to make with MJPEG is the size/compression/quality trade off. We consider SVHS quality to be full screen capture, 30 frames per second, both fields at compression ratios lower then 6:1. At this rate you will get a little over 5 minutes of video (with stereo audio) per gig. Video at this quality requires hard drives that can sustain data throughput over 3.5 megs per second. Professional SVHS video requires compression below 4:1, requiring data rates of 4.5 megs per second or higher!

If you plan on using data rates over 3.5 megs per second or making videos over 5 minutes long, we strongly recommend you get a dedicated video storage solution. Either SCSI, VideoRaid or FastTrack. These solutions will let you capture and play back very long video segments without dropping frames.

NOTE: While MJPEG is excellent for delivering fantastic video quality out to tape, it is a poor choice for multimedia. MJPEG is a hardware compression, so the video files created using it can only be played back in computers with the MJPEG hardware installed. You can convert your MJPEG files into other CODECs using your video editing software, but this can take a long time and result in significant video quality loss.

2.MPEG-1

MPEG-1 is the ideal choice for creating multimedia or web based video. Unlike MJPEG, MPEG-1 is designed to pack a large amount of good quality video into a small file. It is a low loss compression method. Best of all, today’s multimedia Pentium can play back beautiful full screen, full motion video on your computer monitor. Current versions of Win95 include an MPEG-1 player, so any one can take your MPEG-1 files and play them on their computer. This makes MPEG-1 ideal for creating video CD ROMs and multimedia. Using MPEG-1 you can pack over 10 minutes of VHS quality video onto a single 100Mb zip disk!

3.DV

This is the latest and greatest technology to hit video. The IEEE1394 standard allows super high speed data transfers. The 3rd generation of FireWire cards are now shipping. The CODEC used is very similar to MJPEG, with less loss. It is roughly equal to 5:1 compression or a data rate of 3.7 megs/sec. The DV video compression is fixed, it is not scaleable. You can’t lower the screen size, change the screen size or data rate. But don’t let the relatively low data rate fool you. DV video looks as good as MJPEG video at data rate over 5 megs per second! One of the biggest advantages of having a fixed data rate of 3.6 megs per second is that sustaining it is a breeze for todays screaming fast computers. In fact with a PII 350+, 128 megs SDRAM and a big 10+ GB UltraDMA drive you can add one of our inexpensive DV capture cards and edit.

We now sell more DV capture cards then any other format. By year end ’99 more DV cams will be sold each month then SVHS or Hi8. DV is the future of video. If you are planning on getting a new camcorder, make sure it is a DV cam, that fully supports two way FireWire.

4.MPEG2

We are on the brink of a video revolution that is going to make digital video production easier, faster and less expensive. MPEG2 is the first video compression that supports non-linear editing for all formats of video. VHS, 8mm, Hi8, SVHS, DV, DVC Pro on up to broadcast quality. Even more important, MPEG2 video can be put on CD-ROM, Video CD, and DVD or you can stream it over the Internet. Even better, the newest MPEG2 chipset from C-Cube supports real time, dual stream 2D transitions and effects! It looks like it’s going to be the Holy Grail of digital videography. A few years from now, we may look back at the Summer of ’99 as the beginning of the end for video tape and the transformation of video from a linear medium to one of random access. Just imagine having all your video archived on CD or DVD. If you want to find all the clips of the family dog, you just pull them out of the index. Want to skip from the baby being born straight to the first home run she hit in little league? No rewinding, fast-forwarding or searching. Every scene is indexed and just a click of the remote or mouse away. We can see the future of video, and tape is not in it!!

Best of all, the quality of these MPEG2 based cards is outstanding. MPEG2 is a much more efficient compression then MJPEg, so you can maintain video quality at 1/2 the data rate!! In fact, many of them support Native DVcompression in addition to MPEG2, so you get the best possible video output!

Video Storage

While the video capture card determines the actual video quality of your project, it is the sustained throughput of your video storage that determines whether you drop frames or get perfect playback. If you set your capture card at a higher data rate then your storage can handle, you will drop frames during capture and/or get jittery playback. We strongly suggest a dedicated disk drive for your video clips. If you must use your system drive, make sure you create a separate partition for your video files. The longer the video, the more important your choice of video storage becomes. You may be able to get very good results for a minute or two, but longer video (over 5 min) requires a dedicated storage solution.

This does not mean that you must invest now in super fast storage. Just be prepared that you may have to live with lower video quality until you can get the kind of storage your capture card craves. The good news for digital videographers is that hard drives keep getting faster and cheaper. SCSI prices have fallen dramatically and new EIDE RAID systems are an excellent choice for hi-resolution home digital videography.

A very important issue you need to know about NLE and video storage is the 2GB file limitation in Video for Windows. This means that you can’t create an avi file over 2GB in size. Even though new versions of Windows let you create partitions that are 100s of GB in size, the 2GB avi file limit remains. Note: New rendering technology and playback utilities have made it possible to work around this limitation.

Rendering

Before your edited video can be played back to tape, the computer must “render” or “make” the finished movie as a single continuous avi file. Once this new file is created, you can play it back anytime you like with the click of a mouse. I have added this section because one of the most misunderstood aspects of NLE is rendering. First, as the description implies, you will need to have enough disk space to create your finished movie. Second, the rendering process takes up a lot of computer power and time. The more titles, effects and filters you use, the more processing power, speed and time will be needed to create the finished video. This is the area where more RAM and a faster processor can really make a difference. This is why we recommend a P200MMX with 64 megs RAM as our optimum system. The latest NLE software is optimized for MMX and the additional RAM can make a huge difference in render times.

Rendering can take 10 to 20 times as long as the total time of the finished movie. Rendering times of several hours are not uncommon. Until rendering becomes faster, long videos (over 1/2 hour) are not very practical. This combined with the massive storage required, makes us recommend doing NLE in segments of 15 minutes at a time. If you are planning on creating a movie over an hour long, be prepared for the rendering times involved.

Timeline Playback

Timeline Playback technology has been implemented by most of the leading hardware/software vendors. This new technology allows you to play video directly from the project timeline. All transitions and effects are rendered into temp files and then the entire video is played out to tape. Since a second AVI file is not created, you save a ton of disk space. In addition, if you render out previews of the transitions/effects, they are remembered by the software and do not have to be re-rendered. This decreases the time required to create the new video dramatically. The other key benefit of this technology is that it gets around the 2GB file limitation of Video for Windows. This makes it possible to create non linear edited video up to and over an hour is length (assuming you have the storage).

Real-time

Real-time dual stream playback technology means that you can play video directly from the timeline and that the transitions do not have to be rendered!!!

We now offer several cards that have real-time capabilities. Real-time technology is a combination of hardware, software, special drivers and the speed and power of your computer. Not everything in these cards is real-time. The capture card you get will offer a set amount of real-time transitions and effects. Some of the newer, less expensive cards offer real-time output for analog, but require rendering for DV/FireWire output. The effects and transitions you get that are real-time will vary from product to product, depending on how the engineers have implemented their real-time technology. These cards do have very specific hardware requirements. You must make sure you have the computer power to support this technology. We have added a page to our website that features just our real-time cards.

Which One?

We carry several different video capture cards and software packages that are affordable and work great. All of our video capture cards have video& SVHS/Hi8 inputs and outputs. This means you can digitize the video and store it on your hard drive, edit it, then output your finished video to tape. All of our cards are multi system,and work in NTSC (the US television standard) and PAL (used in many European, South American and countries across the globe). In order to help you decide which of our NLE systems is for you, read the “Video Capture Card Round Up V” Article.

You can also check out our interactive video capture card comparison page. We tell you what operating systems each card works on, what non linear editing software is included and list any special features.

Desktop Video Handbook Part 1

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