Tutorials/SteepleBooklet/IntroductiontoDigitalVideo

From Bjoern Hassler

Contents 1 Outline 2 Introduction to Digital Video 3 Why Use Digital Video? 4 What Do You Need for DV? 5 Digital Video Cameras 6 Desktop Video Issues 7 Introduction to Filmmaking 8 iMovie: The Basics 8.1 Introduction 8.2 Starting a Project 8.3 Editing Material 8.4 Adding Audio 8.5 Saving and Exporting 9 Considering Digital Cameras 10 Appendix I: Glossary of Terms 10.1 A to E 10.2 F to J 10.3 L to P 10.4 Q to T 10.5 U to Z 11 Appendix II: Online Points of Reference/Interest

[edit] 1 Outline

This document is intended to give you an introduction to using MiniDV cameras; encompassing filming; editing and post production; a brief guide to purchasing a MiniDV camera; a helpful Glossary of terms used in the world of digital video recording and production and some useful links to websites to find out more about MiniDV recording.

[edit] 2 Introduction to Digital Video

MiniDV, the popular medium for amateur and professional film makers alike, arrived in 1995 and was immediately heralded as a major leap for amateur filmmakers, saving time and money in creating “home movies” that were of an incredibly high-standard. This massive leap in quality launched MiniDV into the most popular medium for filmmakers on a limited budget, as it enabled instant and easy editing in your own living room, rather than the previous, rather expensive, choice of editing professionally.

With MiniDV, desktop video editing became more and more affordable to every user, as computer specifications and hard disk capacities increased the average home computer can now easily cope with the strains of digital video editing, eliminating the need for expensive components of professional help. Digital video (DV) is stored in a sequence of data (01010110111…) and therefore it is far more compatible, easier to store, transfer and manipulate than its analog counterpart. The simplest analogy to compare modern digital video with older analog systems is to think of DV as an audio CD, while analog as an older LP record. The difference in quality between the two is instantly recognisable on all but the very best LPs, as is true with DV and analog video. Basically put, digital video is any video stored in binary data, rather than analog. DV is an international standard created by a consortium of 10 companies for a consumer digital video format. The original 10 companies included the like of Sony, Panasonic and Sharp, since then others have joined up; there are now over 60 companies in the DV consortium and that number expands every year.

Originally known as DVC (Digital Video Cassette), modern DV uses a 1/4 inch (6.35mm) metal evaporate tape to record very high quality digital video. The video is sampled at an incredibly high rate, similar to many industrial video rates; 720 pixels per scanline, which results in a vastly superior image, but at the cost of using equally vast amounts of data storage. DV uses intraframe compression: Each compressed frame depends entirely on itself, and not on any data from preceding or following frames. However, it also uses adaptive interfield compression; if the compressor detects little difference between the two interlaced fields of a frame, it will compress them together, freeing up some of the “bit budget” to allow for higher overall quality within less storage space. In theory, this means that static areas of images will be more accurately represented than areas with a lot of motion; in practice, this can sometimes be observed as a slight degree of “blockiness” in the immediate vicinity of moving objects.

[edit] 3 Why Use Digital Video?

Digital Video, due to its high sampling rate can produce incredibly high quality movies on a very compact tape format. The quality of digital video is far superior to that of VHS, the video recorder that is commonplace in most homes, and it is far easier to edit and manage for amateur and professional filmmakers than VHS.

Filming in traditional VHS, without industrial equipment worth hundreds of thousands of pounds, is a difficult task, and the processes needed to edit and come up with a finished product is also incredibly laborious; often having to rely on professional companies to do much of the work for you. However, digital video has none of these problems, editing it is simple, and can be done on any modern home computer without the need for additional expensive equipment. The level of quality for digital video, compared to its VHS equivalent, is a giant leap above, and more than worth the inconvenience of the large file sizes it requires.

The difference in quality between DV and VHS is largely down to the number of lines that constitute the final picture. VHS is made of approximately 220 lines, while DV is at approximately 500, over twice as many, and therefore the pictures appear sharper, the colours are more true, and less susceptible to noise and degredation. Due to the nature of digital video, being precisely what the name dictates, a stream of “digital data”, it is far easier and quicker to transfer to a computer, or edit directly into a modern camera. This feature, by far one of the greatest advantages of digital video, is what draws millions of people to make their home movies, hopeful feature films, or television reports, in the medium.

MiniDV cameras also have another advantage over traditional film cameras; their size. The average modern DV camera is approximately the size of a single VHS tape, and they are getting smaller every year. A MiniDV camera can be easily transported in a suitcase, or small carry-bag, and can be easily held when filming. When the cameras were first introduced, many organisations saw the advantages of this, not the least the BBC, who began issuing these small cameras to overseas reporters who might find themselves in dangerous situations and need to make a hasty retreat; with their inexpensive DV cameras, the reporters could film what they needed, and then discard the camera, pocketing the minute DV tape to make a dash for safety. While in the past, camera men had to use vastly larger and heavier filming equipment to get the same quality, and due to the cost of these expensive equipment, were less likely to be able to simply discard them. It is this ease; the light weight and small size of DV cameras, which make them so appealing to such a wide range of individuals and organisations.

[edit] 4 What Do You Need for DV?

To create, transfer, edit and publish digital video, the average filmmaker needs relatively little equipment, all of which is readily available from the average electronic superstore for very low prices compared to their industrial counterparts.

A modern DV camera can be linked directly to Apple’s iMac range of desktop computers merely using one simple FireWire cable. While to link to PCs, or other computers, a third party DV video card is required, but with the ever increasing rate of technological development, more and more modern computers are being built with this technology already in them, making the need for additional components redundant. FireWire cables are what makes DV so easy to manage and edit, these small, singular cables can transfer vast amounts of data, ten times that of a traditional USB connection, exchanging data at a rate of 400 KiloBits per second.

This one, ultra-fast cable replaces the need for numerous additional connectors, cables and devices that used to make video editing such a laborious task. FireWire is the common name for the IEEE 1394 industrial standard, while Sony labels the standard as the iLink. This incredible cable was the result of a joint venture between various engineering organisations, Apple, and Sony. Almost every modern DV camera comes with an IEEE 1394 port, with the iMac series having a built in connection. Many computers also come with multimedia FireWire port as standard, but for a small price there are a wide range of compatible FireWire cards that can be integrated into computers that lack the technology. The FireWire technology is widely used by a wealth of different companies in the production of hardware, and other components that need to exchange data at incredibly fast rates in the easiest possible fashion. In the context of digital video, FireWire has resulted in vast improvements of the management of video data. When using a FireWire cable in a simple setup, the video can be transferred in digital data directly from the camera, without the need to actually “capture” the video again. Due to the nature of the transfer, FireWire also eliminates the possibility of any data loss or error during the transfer, as the computer or camera can recognise when a portion of the digital data has been lost or contains errors, and ask for the device to re-transfer it, correcting the problem without needing any input from the user. This system is not just used for DV, but it is used to connect external hard-drives, scanners, card-readers and many more useful products. Using FireWire between a computer and a DV camera also gives the computer total control over the camera it is connected to, allowing the user to rewind, play, stop or fast-forward the camera from a simple menu on the screen.

[edit] 5 Digital Video Cameras

Digital Video Cameras may look different, but they all have the same fundamental features and abilities, regardless of brand or cost. For the purposes of this document, the features are described as on the Panasonic EZ35 MiniDV camera.

On/Off Toggle Switch: Located at the rear right of the camera, ideally placed next to the users thumb to allow easy manipulation of the controls. The toggle switch is slid to the right or left to switch the camera on or off respectively. It is always good practice to switch the camera off whenever in use, as the battery life can be used up quickly.

Record Button: Located inside the On/Off toggle switch, the red record button is the most important feature of any MiniDV camera, and is coloured in bright red for easy recognition. Pressing the button once will set the camera capturing video, while pressing it again will cease it recording.

Eyepiece/Viewfinder: Located at the top rear of the camera, the user looks through this eyepiece to observe what the camera can see. This aperture can be pulled back slightly, and then tilted upwards at the users’ discretion. Note that the viewfinder will only be active if the LCD display is closed.

FireWire/IEEE 1394 Terminal: Located at the rear of the camera, concealed by a small rubber flap, is the terminal slot for the FireWire cable. An essential aspect of the camera, this allows for easy transfer of data. It should be noted however that some cameras are DV out only, and cannot take DV in.

Battery Compartment: Located at the bottom rear of the camera, this compartment houses the battery, or mains power-pack that powers the camera. The small button in the centre of the panel locks and unlocks it, while the small grey switch inside the compartment releases the battery itself.

LCD Flip-Out Monitor: A small flip-out monitor is often integrated in most modern cameras, once open; the image that the camera can see is displayed on this screen instead of in the viewfinder. A small catch at the rear of the camera releases the screen, which can be tilted and rotated as desired.

Camera/VCR Mode Button: Another important feature of any MiniDV camera is the camera or VCR mode button. This button, located on the right side of the camera, at the rear, will put the camera into either VCR mode (for playback of the data on the camera, or needed when connecting the camera to a computer) or conventional camera mode (normal mode for filming). Generally, a little red light will highlight which mode the camera is in.

Zoom Button: Located at the top right of the camera, the small zoom bar enables the camera to enlarge or decrease the image that it sees, focusing tight, or focusing wide, on different items.

Photo Shot: Some cameras also have the ability to take still captures of what they see; it is this button that controls this feature. Once pressed, it will capture a single image.

Eject and Lock Buttons: Since MiniDV cameras record video onto MiniDV tapes, the lock and eject button controls the opening and closing of the tape compartment. The small eject slider on the middle left of the right side of the camera releases the compartment, while the lock button the compartment itself will seal the tape compartment back in place.

MiniDV Tape Compartment: The MiniDV tape is inserted into this compartment.

Shutter/Iris Control: This small wheel closes and opens the iris of the camera. Gradually closing the iris will restrict the amount of light that passes through into the camera, while opening it will gradually increase the amount of light; serving to lighten or darken the video.

Automatic/Manual Slider: This small button, located on the left front of the camera controls the focusing feature of the camera. While in automatic mode, the advised mode for all but the most advanced users, the camera will automatically focus on what it thinks it is being pointed at, generally this is acceptable. But, sliding the bar down to Manual will place the camera in manual mode, where the user will manually adjust the cameras’ focus using the large wheel at the very front of the camera, just behind the lens. Putting the camera into automatic mode should only be used if the camera is not focusing on the desired object.

Menu and Select Button: Located on the left side of the camera, at the very front is the menu and option select button. Pressing the menu button will open the cameras menu mode, with the options being displayed in the flip-out LCD display. Pressing the option select button will allow navigation and manipulation of the items available in the cameras’ menu. Generally, the menu should not need to be changed except when attempting more advanced filming.

Sensors: At the very front of the camera, underneath the lens are an array of sensors that permit the camera to determine the distance of objects from it, and the amount of light &c. Generally, the sensor is in the form of a small clear red plastic section, and should not be obscured while filming.

Lens: The fundamental feature of any camera, the lens is situated at the very front of the camera, and is often surrounded by a large rubber frame. It is through the lens that the camera will record and see objects, the lens also contains the iris and it is through the lens that light will enter in order to enhance the image. Therefore, the lens should not be obscured and should be treated with great care. When not in use, it is good practice to keep the lens-cap on so that no dirt can reach the lens itself.

Playback Controls: Situated on the very top of the camera, this small array of buttons controls the camera playback option, permitting the user to rewind, fast-forward, stop, play and, when the menu is selected on the LCD screen, to perform various other tasks. A common mistake is trying to use the playback controls when in camera mode, but they will only work when the camera is switched to VCR mode.

Mic: Situated on the top of the camera, at the very front, is the mic. A hugely important feature of the camera, as it is through this small tool that all the audio is recorded onto the final video. The mic will attempt to focus in on strong audio that originates from directly in-front of it; therefore it is good practice to get any audio as close and forward of the mic as possible. Just to the rear of the mic is a small slot that has an opening for larger mics to be slotted into to it, in order to rest on the top of the camera.

Adapter: On the very bottom of most cameras is a small covered slot that permits a conventional camera adaptor to be attached to the bottom of the camera.

Tripod Socket: Also situated on the very bottom of the camera, a small hole is available in order to secure the camera onto a tripod. When using a tripod (which should be as often as possible) the camera should be tightly secured onto the small screw on the tip of the tripod so that the camera can not slip or move while filming.

[edit] 6 Desktop Video Issues

Editing video on a desktop is one of the most useful features of MiniDV technology, but doing so does put a huge strain onto a computer, and therefore it is advised that editing is done on a relatively powerful modern computer, with plenty of available disk space.

Editing and transferring digital video requires a large capacity of storage space, and a very fast computer processor. It is heavily advised to have at least a 10 Gigabyte hard drive before even attempting to edit lengthy selections of digital video, as it quickly uses up large amounts of a hard disk.

1 Second of Digital Video = 3 Floppy Disks 5 Minutes of MiniDV Footage = 1 Gigabyte Storage

Due to the high requirements of storage needed, it quickly becomes apparent that the transfer of digital video using conventional methods is near impossible, after-all, who would like to carry around several shopping bags of floppy disks for a mere few minutes of footage? Digital video uses such vast amounts of storage because it is of such an incredibly high quality, therefore sacrifices have to be made somewhere in order to retain such quality. There are several options open to a user on what to do with their video, the first is to transfer the finished, fully edited high quality video back to the digital video camera itself, this is good practice, as it means there will be a full-quality version of the finished film on archive for the future. The second option is to merely save the full quality version onto a hard disk, but due to the large file size, this is rarely the practical answer.

The other options all begin with compressing the full quality version into a smaller file. Compressing a video file is a paramount feature of modern digital video, and is vitally important when considering how to display your video to others, whether that is on a CD-ROM, or via the internet. There are many ways to compress video, and all video editing software titles will have options for a range of different compression types tailored to the different presentational mediums.

The most useful modern compression techniques are tailored to be displayed by a range of processes over the World Wide Web. Due to the wide variation of data rates that modern users connect to the World Wide Web over, it is often necessary to dramatically reduce the size, and thus the quality, of the video. Raw digital video is viewed at over 3,500 Kbytes per second, which is undoubtedly impossible to display over the internet, therefore compression is needed from the very beginning. But the different types of compression are tailored to the different types of connections that the video will be displayed on; larger files, and thus videos of a higher quality are ideal to display over corporate intranets, or T1 connections, as the videos require a huge data rate. As the desired connection rate decreases, so does the size and quality of the video needed, incredibly compressed videos are required if a user on a slow modem is to view them, and due to this heavy compression, the final video file will be much, much smaller with a corresponding drop in quality. It is always a compromise between file size and quality.

High Quality Video = Huge File Sizes Low Quality Video = Small File Sizes

[edit] 7 Introduction to Filmmaking

Filmmaking in digital video is just like filmmaking in the conventional sense; you need to know what you are going to film and how you want to do it. The easiest way to gather ideas before venturing to make your own film is to look around you; watch TV, especially adverts and identify what they’re showing, and how they’re doing it. In the modern world filmmakers need to keep different clips rolling, an interesting statistic is that the average length of clips on American television are a mere 3 seconds, so there is no need to concentrate on one thing for 15 seconds, before moving in a linear fashion to the next. There are no rules that state you must show all of one clip before showing another; long clips can be made more varied and hold the attention of the audience better is they are broken up with other clips.

Having a grasp of a specific theme and narrative when approaching the recording of digital video is greatly to your advantage. Know what you want to film before pressing the record button, and stop when you’ve captured it before you search for more images. Pressing record and then searching for the image you want is a classic “home movie” blunder, and should be avoided whenever possible. With a narrative, think of a beginning, middle, and an end. Very simple principles that will greatly enhance the overall effect of the final movie. Plan how you want a film to begin, and film a certain clip with that in mind as the beginning frame, and film another scene with that in mind as the end, you don’t have to use them in the final product, but it helps to have them there, and helps you to think of the structure of the film. When using a MiniDV camera in your filmmaking, use a tripod! Using a tripod to stabilise the camera greatly increases the effect of the film, and makes it more enjoyable to watch. Filming scenes with the camera in your hand will only make it uneven and “jiggly” and should be avoided unless you definitely want that effect.

Try to record with plain backgrounds; items such as trees and water in the background of your main focus point only puts far more strain on the camera, and the final result will look strange, especially if it is going to be compressed for the World Wide Web.

Don’t be afraid to use the zoom feature to tightly frame what you’re focusing on. Tight framing is used a vast amount by professionals as it is just that, professional. The so-called “talking heads” image is more interesting than carefully positioning the camera several metres from your target, and if it is going to be compressed, the tighter the image, the easier to recognise it will be. Audio is possibly the most powerful asset to digital video, recorded correctly it can greatly boost a mundane film into being interesting, and an interesting film to being a marvellous film. Take care in the position of microphones when recording audio, and position the source of the audio as close, and directly in front of, the microphone. After all, television without audio is nothing, but audio without television is radio.

[edit] 8 iMovie: The Basics

[edit] 8.1 Introduction

iMovie is a free piece of software that comes with Apple’s Macintosh Operating Systems and is meant to work with their complete DV package that is integrated into their iMacs and other available desktop computers. Due to its relatively simple nature, iMovie is targeted at beginners and those who have only just begun editing with digital video, and the features it has are tailored to that fact. Despite this, iMovie is still a powerful and incredibly useful piece of software to digital video filmmakers, and it enables a user to create a relatively good finished video, compress it, and release it to the public in an incredibly short period of time.

iMovie is only available to Macintosh users, thus PC users are restricted primarily to the commercial editing products (Except for Windows XP users, who have an in-built editing software included) like Adobe Premiere or Ulead Video Studio.

[edit] 8.2 Starting a Project

Once beginning a new project in iMovie, it is good practice to begin a new Project in the iMovie window. To create a new project, go to File>Create New Project.

After creating a new Project, the next step is to transfer the video from the camera to iMovie, this process is referred to as “log and capture”, and is one of the processes that may take a lengthy period of time, dependant on the length of film that is being captured. The first step in this process is to ensure that the DV camera is connected to the iMac via a FireWire cable, has a DV tape in it, and is on “VCR Mode”. Following this, use the controls on the main iMovie interface to rewind the DV tape to the beginning (or where you wish to begin importing), after which you should use those controls to select the “Import” feature. Once selected, the import button will automatically play the contents of the camera and begin importing it to iMovie. iMovie will load all the clips that you are importing to the frame on the right of the interface, splitting the clips where it thinks there is a change in appearance. While doing this, the small “fuel gauge” below the frame where the clips are being put will begin to move, this gauge registers the amount of free disk space you currently have and it is heavily advised to keep an eye on this amount as raw digital video uses up vast amounts of data very quickly.

At the bottom of the main frame, and the clip frame you can see a long rectangular frame; this is the Timeline frame and where the clips from the clip frame will be assembled. Once the log and capture process has finished it is good practice to check all of the clips that have appeared, and name them according to the images that appear within them. This will prove useful when identifying what each clip is. To do this you can either double click on the clip to bring up its properties, or edit the name directly in the clips frame.

[edit] 8.3 Editing Material

Once the capturing process has finished, and the clips have been named, you will need to watch the clips and amend and modify them accordingly, ridding them of unwanted material and trimming them to desired sections. The method to do this is to do it as quickly as possible, selecting the points where you would like the clip to begin and where you wish it to end. Using the cursor, drag the line in the main frame to the start point, hold down the Shift button, and drag the cursor to where you wish the clip to end. This should select the option you want, highlighting it in yellow. Once you have the correct piece selected you need to Crop the item, to do this you select Edit>Crop.

This process will trim the clip to only the highlighted section, getting rid of the blue section of the clip. You should follow this process through all your clips, until you have them all quickly edited to include only the sections you want. The discarded sections will be sent to iMovie’s own Trash Bin, and it is good practice to empty this as often as you can in order to free up some more disk space for your editing. Once this is done, you should begin to lay your movie in the timeline frame. You do this by dragging and dropping your clips into the timeline frame. Once in that frame, you can drag and drop them into any order that you desire.

[edit] 8.4 Adding Audio

After you have the clips in the desired order, you could move onto adding the various sections of audio you wish to include in the final movie. Once of the easiest and most useful abilities is to record a voiceover directly into the computer through its mic. Once you are sure you have a mic, or have plugged in a simple external one, select the Audio tap in the same frame that your clips first appeared. With this done, move the cursor so that the small horizontal line with a triangle on the top, in the timeline frame, is positioned where you wish the voiceover to begin. With this selected, simply press the Record Voice button on the right frame and begin talking into your mic, once you have finished talking, press the button again to stop the recording.

Once you have finished recording, it should create a yellow selection in the first audio track of the timeline, as below.

iMovie provides you with two audio tracks, clearly labelled 1 and 2, as above. This allows you to input several selections of audio, as well as a soundtrack. You may wish to record a soundtrack from a CD, the process to do so is simple and quick. First insert the audio CD into your computer, and, still on the audio tab, it should appear on the bottom layer of the frame. It will list all the tracks on your CD, therefore select the desired track and click Record Music.

iMovie will begin recording your music, and will create it in the lower track, highlighted purple. iMovie automatically places different music items into the two different tracks so that you will not inadvertently lay several layers of audio over one another. More advanced editor packages will provide you with more audio tracks, but iMovie does not.

With the audio tracks laid down, you may wish to add in some Effects to your movie, either over portions, or the entire movie. To do this you need to select the Effects tab in the same frame as the clips and audio. This will bring up a frame displaying all the effects available to you, and if you select one of them, it will generate a small preview in the upper right window showing you what it will look like when rendered. In order to lay down an effect, select the clips you wish the effect to be on (in the timeline frame at the bottom) and then select the effect from the list. After you have the chosen effect selected, select Apply and iMovie will begin to render the effect onto the clips that you highlighted.

Rendering means the applying of the effect or transition onto the clips, it refers to the process that iMovie follows of adding the effect onto every frame in the clip. iMovie displays how far it has got in the rendering process by using a little red bar that gradually increases until the rendering is complete.

iMovie also enables you to add Titles to sections of your film. To do so, select the Titles tab in the same frame as the Effects tab, this will bring up another list of the available title effects, and will give you several text windows to write the text that you want to appear on your movie. Once you have inputted your text, and selected the style of the title, click the clip that you want it to appear on, and click Preview. This will generate a full scale preview in the main window on the left so that you can view what your title will look like. Once you are happy with it, you need only click Update and iMovie will begin rendering the title to your clip. Once again this may take a few moments, and you can see how far it has got in the process by the little red bar under the clip in the Timeline frame (As above).

Once you have ordered and cropped all your clips to the desired final appearance you may begin to add in different transitions. Transitions are effects that are put in between two clips to make the “transition” between them smoother or more interesting than the sharp cuts that would happen if you didn’t have any. It is advised to include as few of these different transitions, effects and titles as possible, as too many will detract from the actual film and make it appear “gimmicky”. To add a transition select the Transition tab in the same frame as the other effects and titles, which will bring up a list of all the available transitions, and any options you may have with each one, such as the direction or speed of the transition. Select the transition you desire, and click Preview; this will show you what the finished transition will look like in the large frame on the left. One you are happy with the appearance, select the transition again and drag it between the two clips you want it to appear between.

Once again, iMovie will begin to render it. Transitions are displayed by a little square box between the two clips, and they can be deleted at any point if you decide you don’t like it.

[edit] 8.5 Saving and Exporting

Once you have repeated all these processes and are happy with the finished product, you will need to save, and then export the movie. You will need to export it, unless you only want to show people from the computer you edited in. iMovie comes complete with a range of export options, all of which serve to compress the final film into a relevant form. There are several options open, back to the camera (which exports the full un-compressed movie to back to the DV tape in your camera), to iDVD (a special format for producing DVD-Video on a Macintosh computer) or to Quicktime. Quicktime is the desired format for most filmmakers, as it gives you further options of how you will want to display it (for the internet, for e-mail &c). To export a film select File>Export and then select the option you want it to export your finished movie to.

If you select Quicktime, iMovie will provide you with several more options to decide. Each of these has certain preset values that Apple thinks you will need the most. All of these are self-explanatory. But, if they are not acceptable it is possible to click Expert and create your own specific size and options. This is complicated if you do not know all the specific values you will need, therefore, in most circumstances, iMovies’ preset examples will serve best.

Once exported, all that is left to do is save your project, get rid of any unwanted items (into the Trash Bin) and admire your finished project.

[edit] 9 Considering Digital Cameras

Buying a Digital Camera can be a daunting task, but by considering the following key features you should be able to create a basic specification to take with you on the hunt. Size: Sleek and compact, digital video cameras are smaller than the camcorders of old. New models are so compact that many fit in one hand. They are truly "take anywhere" cameras and marvels of miniaturization.

Resolution: The difference with digital video is in the multipixel, up to 500-line resolution which is presented via a CCD (charge-coupled device) imaging screen. The CCD is measured in pixels. And the more pixels, the better. DV cameras offer 680,000 pixels to a whopping megapixel (one million pixels) for amazingly sharp, crisp digital video. With digital video, making copies from one camcorder to another is easy and there's virtually no loss in quality.

LCD Screen: There may be a viewfinder, but one of the luxuries of a digital camcorder is also an LCD screen (or a viewscreen). With an LCD screen, you can better see where you're going when trying to capture a scene. Most digital video cameras have both the traditional tilt-up viewfinder on top and a bigger flip-open colour LCD screen on the side. Image Stabilization: Image stabilization (or sometimes called picture stabilization) makes movies viewable without annoying camera shakes. This feature is a must for zoom shots for easy-to-view close-ups. Stabilization tip: Use a tripod wherever possible for ultimate stability.

Zooms: Digital video cameras have both optical and digital zooms. Even though the digital zoom claims of three-hundred times and up sound enticing, this feature lends too much magnification and images are blurred. The optical zoom is what you'll want to use, so get a camera with a long optical zoom range (i.e., 16x and higher) and start recording great footage at a distance.

Connectivity: Look for a digital camcorder with a FireWire (IEEE 1394) connection, also called iLINK and DV In/Out. On most MiniDV cameras, this jack is the key to digital editing. Though you can use a video capture card or device to import video into your PC, the speed and ease of transferring it through a FireWire or iLINK port is unrivalled. Video can transfer through an IEEE 1394 at up to 400 Mbps, much faster than a standard port. The camcorder connects right to the PC for easy transfer. It should be noted that some cameras only have DV out capabilities, and not DV in. We would strongly advise against getting such cameras.

There is no specific camera that you should buy; it all boils down to personal preference and ease of use. Some may find one camera easy to use while others may not. The easiest way to discover which would be the best for you is to try them. Identify the task that you will most likely use the camera in, and search for one you like and feel comfortable with based on that. Prices greatly differ on digital video cameras, anywhere from several hundred to several thousand, dependant on what you may want to use the camera for. The fundamental difference between cameras that may cost several thousand, from one that costs several hundred is often the CCD; the quality of colour on the camera.

[edit] 10 Appendix I: Glossary of Terms

Throughout the Digital Video Course the Staff and Notes may refer to many terms and abbreviations, therefore, the definitions for a range of relevant terms are included below. All the terms included may prove useful in creating and editing your own digital video, and may answer some of the questions you may have.

[edit] 10.1 A to E

8-Bit: Colour depth that permits 256 colours to be displayed at any one time.

16-Bit: Colour depth that permits thousands of colours to be displayed at any one time. This is commonly referred to as Thousands of Colours on Macintosh Operating Systems, and High Colour on Windows Operating Systems.

24-Bit: Colour depth that permits millions of colours to be displayed at any one time. 24-Bit images can often retain a photographic quality. This is commonly referred to as Millions of Colours on Macintosh Operating Systems, and True Colour on Windows Operating Systems. Aliasing: Commonly referred to as “jaggies”, these are the ‘stair’ patterns that appear on the edge of diagonal or curved lines on a computer or video display. They can usually be removed by an Anti-aliasing function.

Alpha Channel: An 8-Bit colour channel that is used to specify the transparency of each pixel of an image. An Alpha Channel is the digital equivalent of a matte.

Analog: Information represented electronically as a continuous, varying signal. Commonly an older version of transferring a range of data.

Anti-Aliasing: The process of eliminating “jagged” edges on computer-generated text and graphics. Anti-aliased graphics have their edges slightly blurred and mixed with background colours to eliminate the jagged, stair stepping patterns that can occur on diagonal, or curved lines.

Aperture: On any camera, light is focused onto the lens through an aperture and unto a focal plane. The size of the aperture controls how much light is focused through. In addition to controlling the brightness of the exposure, the aperture controls the depth of field in the image. By balancing the size of the aperture (as measured in f-stops) with the shutter speed you can trade off between varying depth of field, and or the ability to better-resolve fast motion.

Aspect Ratio: Width to height ratio of an image. This can be expressed as a ratio (4:3, 16:9) or as a number (1.33).

Asymmetric Code: A Codec that takes longer to encode than decode. Most modern codecs are asymmetric code as speed is essential when playing back frames of a video.

Audio sampling rate: The number of samples per second that are used to digitize a particular sound. Most DV cameras can record at several audio sampling rates. Higher rates yield better results. Measured in kilohertz, 44.1 kHz is considered audio CD quality and 48 kHz is considered DAT quality.

Bandwidth: The amount of information that can be sent, processed &c, in a given amount of time. For example, a 2x CD-ROM Drive has a maximum bandwidth of 300 Kbytes/sec, while a 28.8 modem has a theoretical bandwidth of approximately 3 Kbytes/sec.

B-frame (Bi-directional frame): An MPEG difference frame that is based on both the previous and next frame. It is similar to a Quicktime Delta frame, but with the ability to see what is ahead.

Bin: A film-editing term that refers to the place where the shots for a scene are stored. In software editing systems, bins can also be referred to as folders, galleries, or libraries.

Bit (Binary Digit): A unit of measure for computer data. A bit is a single computer digit (either a 1 or a 0). Eight digits make up a Byte.

Bitmap: A collection of pixels that make up an image. Commonly used to distinguish images that are pixel based to those that are vector based.

Broadcast Colours: Your computer monitor can display many more colours than normal TV can. Broadcast colours are those colours that are safe – that is, they will display properly – for use in broadcast video. Many programs, such as Adobe Photoshop and Adobe After Effects, include special filters that will convert the colours in an image to their nearest broadcast safe equivalent.

Broadcast quality: A relatively vague term, referring to the minimum quality considered acceptable for broadcast television. Until the 1980s, 3/4” Umatic tape was considered broadcast quality, and then Betacam SP was introduced and became the standard for broadcast quality. Today, MiniDV is often considered broadcast quality due to the fact that the final master is usually Digital Betacam.

CCD (Charge Coupled Device): A special type of chip that can convert light into electronic signals. A DV camera focuses light through a lens and onto a CCD where it is converted into electronic signals that can be stored on tape. Many modern, hi-grade DV Cameras have 3 CCD.

Channel: The colour in an RGB image is divided into channels, one each for the red, green, and blue information in the image. When these channels are combined, a full-colour image results. Certain effects are easier to achieve by manipulating individual colour channels.

Chroma Key: A special key function that will render a specific colour in a layer transparent. For example, if you shoot someone in front of an evenly-lit blue screen, you can use a chroma key function to render the blue completely transparent, thus revealing underlying video layers. This is a commonly used function in the film industry to impose actors onto computer generated surroundings.

Chroma: The element of a video signal that contains the colour information.

Chrominance: A colour component of an image.

Cinemascope: A very wide (2.21:1) aspect ratio that is one of the standards in MPEG-2. When displayed on a normal television, Cinemascope material requires pronounced “letterboxing” (black bars on the top and bottom of the screen). Similar to that of many widescreen effects now available.

Cinepak: A Quicktime codec used primarily for CD-ROM video compression. It allows temporal and spatial compression, as well as limiting the data-rate. Newer codecs offer superior image quality and features, but Cinepak is still used for backwards capability.

Codec (Compressor/Decompressor): A software component that translates video or audio between its uncompressed form and the compressed form in which it is stored. Sorenson Video and Cinepak are common Quicktime video codecs, while the MPEG series are common, industry-standard examples.

Colour Depth: The possible range of colours that can be used in a movie or image. There are generally four choices with video; Greyscale, 8-bit, 16-bit, and 24-bit. Higher colour depths provide a wider range of colours, but require more space for a given image size.

Colour Space: A mathematical model that describes colours. RGB, CMYK, HSV and YUV are common model of colour spaces.

Colour Sampling: The method of reducing the size of an image by storing colour data with lower resolution than luminance data. Typically used in video with the YUV colour space.

Compression: In multimedia, this term means the compression of a file. Commonly referred to as encoding.

Data Rate: The amount of information per second used to represent a movie, often expressed in Kilobytes per second (Kbytes/sec). A single speed CD-ROM movie is usually made at a data rate of 100 KBytes/sec and a double speed CD-ROM movie about 200 Kbytes/sec. The data rate of uncompressed NTSC video is about 15 Mbytes/sec.

Decibel: The standard unit for measuring sound. A subjective scale where one unit equals one increment of “loudness.”

Delta Frame: Frames that contain only changes from the previous frame. Delta frames are created by codecs that use temporal compression. Delta frames are also called difference frames.

Digital: Information recorded electronically as a series of discrete pulses, or samples, usually using a binary system.

Digitising: The process of taking analog video information from a camera or deck and turning it into digital information that can be used by a computer.

Diopter: An adjustment on the eyepiece of a camera that allows you to correct the focus of the eyepiece to match your vision.

DVD-Video: A version of the DVD disk format used for storage of pre-recorded movies that is expected to replace VHS. The DVD-Video specification uses MPEG-2.

Electronic Image Stabilisation: Special circuitry in a camera that attempts to compensate for shaking and vibrating by electronically shifting the image to compensate for camera movement. Electronic image stabilisation frequently results in a slightly blurred image.

Encode: The process by which files are reduced in size by the removal of redundant or less important data.

Equalisation: The process of adjusting the volume of individual frequency ranges within a sound. Equalisation can be used to correct problems in a sound, or to “sweeten” or enhance the sound to bring out particular qualities

Exposure: The process of allowing light to enter the camera, exposing the film or video stock to light, which results in a recorded image.

[edit] 10.2 F to J

Fast Start: A progressive-steaming feature of Quicktime that allows movies to be viewed in a browser before the entire movie has been fully downloaded.

Field: Half of an interlaced video frame consisting of odd or even image lines. Alternating video fields in PAL (UK television) are drawn every 1/50 of a second to create 25 frames per second (fps) video.

Filters: Special glass attachments that can be added to a camera lens to change the optical properties of the lens. Or, special pieces of software that can be added to a host application to perform special image processing functions.

FireWire: Apple’s trademarked name for the IEEE 1394 standard.

Flat Field Noise: Slight differences in areas that should be identical. Although not often objectionable by the human eye, flat field noise degrades the compression and may be removed using some software’s built in filters.

Flattening: A final pass applied to a Quicktime movie that ensures that the movie data us laid out in a linear fashion and all external references are removed so that a file can be played on a Windows machine. It also ensures that the sound is interleaves properly with the video.

Focal Length: The size of the angle of view of the lens, measured in millimetres. The smaller the number, the wider the lens. Zoom lenses have a range of focal lengths.

Focal Plane: The area in a camera onto which light is focused. In a film camera, the film rests on the focal plane, in a digital video camera, the CCD rests on the focal plane.

FPS (Frames Per Second): The measure of the frame rate of video or film. PAL video is 25 fps and film is 24 fps.

Frame: One single image among many that make up a movie. A conventional video frame is made up of two fields. A film frame is a single photographic image, and does not have separate fields.

Frame Rate: The number of frames per second in a movie.

Frequency: An audio signal is made up of different frequencies, or wavelengths, which yield the high (or treble), mid and low (or bass) tones. The human voice resides mostly in the mid-tones

FTP (File Transfer Protocol): A common internet protocol used to transfer files between computers.

Gain: The strength (or amplitude) of an audio or video signal.

Gamma: The curve that describes how the middle tones of images appear. Often confused with brightness/contrast, gamma is a non-linear function. Changing the value of the gamma affects the middle tones while leaving the white and black of the image unaltered. Gamma adjustment is commonly used to compensate for differences between Macintosh and Windows video cards and display.

Hard Cut: An edit from one shot to another without any sort of transition in between.

HSV (Hue Standard Value): The colour space that defines in terms of their hue (the colour of an object, such as green), saturation (how much grey is in the colour), and value (the lightness or darkness of the colour). Variations on this colour space include the HSB (Hue Saturation Brightness) and HSL (Hue Saturation Lightness).

HTML (Hyper Text Transfer Protocol): The most common protocol used on the World Wide Web to transfer and view pages in a web browser.

IEEE 1394: Also known as FireWire, or iLink, it is a very high speed serial protocol often used to connect DV cameras to computers. IEEE 1394 is widely applicable to consumer electronics that move large amounts of data. This protocol is incredibly fast at transferring data with almost no data loss during the process.

I-Frame (IntraFrame): A complete MPEG frame containing the entire image. This is the same as key frames in Quicktime/AVI.

Illumination: The amount of light cast onto an item or object.

IMA: 4:1 compression audio codec that words with 16-bit audio. A standard created by the Interactive Multimedia Association.

Indeo: A family of several codecs developed by Intel, now owned by Ligos Technology, that allows temporal and spatial compression, as well as data rate limiting.

Intelligent Streaming: Windows Media scalability feature that allows multiple versions of a file to be encoded in a single file and delivered to viewers based on their connection.

Interlaced Video: Each PAL video frame consists of two fields. When displaying video, a PAL television displays one field every 1/50 of a second. Our eyes put the two alternating fields together to create 25 whole PAL frames per second. This effect is undesirable for multimedia applications and should be removed (de-interlaced) prior to compression.

Interleaving: The process of intermixing the video and audio data into one final file. Interleaving is required for proper playback of movies because it allows the drive to read the file in a linear fashion and still receive the separate audio and video data as needed.

Iris: Synonymous with aperture. The iris is the physical mechanism that can be opened or closed to change the size of the aperture. “Irising down” for example, means to close down the iris (go to a higher f-stop).

ISO-9660: A format for writing CD-ROMs. Can be read by either Mac or Windows-based computers.

JPEG: A graphic format developed by the Joint Photographic Experts Group. JPEG is a bitmapped image format that is widely used for online graphics. JPEG works well for photographic images.

[edit] 10.3 L to P

LAN (Local Area Network): A network that connects computers within a geographically small region, usually within one building or campus.

Lens: Usually a series of separate glass lenses, the lens on a camera is what focuses light onto the focal plane to create an image.

Live: Video or information that is captured, compressed or distributed in real time, such as live broadcasts.

Lossless: Used to denote a form of compression that does not degrade the quality of the image being compressed.

Loss: Used to donate a form of compression that does degrade the quality of the image being compressed.

Luminance Key: A special key function that will use the luminance values in a layer to determine the transparency of that layer. For example, a luminance key could be set to render the darkest areas of the layer transparent

Luminance: The strength (or amplitude) of the grey scale (or brightness) portion of a video signal.

Metadata: Additional identification information that is assigned to a movie or image using a series of protocol standards or hidden watermarks.

MIDI (Musical Instrument Digital Interface): An architecture protocol that is used to instruct musical instruments how to play a specific notes of music.

MPEG (Moving Picture Experts Group): The file format name and extension used to donate the industry standard protocol for video and audio that was jointly developed by the Moving Pictures Experts Group. The various forms of the MPEG codec are widely used in a diverse range of multimedia situations.

MPEG-1: The format that produces high quality video and audio streams at approximately 2 x CD-ROM data rates. Standard MPEG-1 is full frame rate (24-30 fps, depending on the source) with a quarter size image (352x240 NTSC) and is useful for playback on most desktop computers. Like all the MPEG versions, .mpg is the commonly used filename.

MPEG-2: The format that produces high quality, full broadcast quality files. MPEG-2 playback requires an extremely fast computer and video card or a hardware accelerator card. MPEG-2 is the format for DVD-Video and many home satellite dish systems. Standard MPEG-2 is full frame rate and full resolution.

MPEG-4: An international video format used by Windows Media and other systems for web video that produces good image quality at low bandwidths. MPEG-4 is fairly CPU intensive, so larger frame sizes and frame rates may require fast computers.

Multimedia Architecture: Software, including system extensions, plug-ins, severs &c, that provides for the creation, storage and playback of synchronised multiple media types.

Noise: Any element of a video or audio signal with unwanted randomness. In audio signals this is generally the adding of hiss or fuzz noises, while in video an image can appear to have a grain effect, or another unwanted change of the original image.

Non-linear editing system: A digital editing system that uses a software interface and digitized audio and video stored on a hard drive which allows for random access, non-linearity, and non-destructive editing.

NTSC: An acronym for National Television Standards Committee, NTSC is the broadcast video standard for North America and Japan, with a frame rate of 29.97 fps and 525 horizontal scan lines.

Optical image stabilisation: A special optical apparatus in a camera that attempts to compensate for shaking and vibrating by altering the camera’s optical properties on-the-fly to compensate for camera movement. Because OIS doesn’t alter your image data, there is no image degradation.

Overexposure: Overexposure refers to video or film that was shot with too much light or the wrong camera settings, resulting in a whitish, washed-out, faded-looking image.

PAL: An acronym for Phase Alternate by Line, a television standard used in most of Europe and Asia, with a frame rate of 25fps and 625 horizontal scan lines, resulting in somewhat higher quality video than the American NTSC.

Pan: To rotate the camera left and right around the camera’s vertical axis.

P-Frame: MPEG difference frame that looks to previous frames. Same as a Quicktime/AVI delta frame.

Pixel: One dot in a video or still image. A very low resolution computer screen is 640 pixels wide and 480 pixels tall. Digital video movies are often 320 pixels wide and 240 pixels tall.

Pixelisation: When the pixels of an image are defined or exaggerated, making the image appear as many large blocks of colour.

Progressive Streaming: A term referring to online media that viewers can watch as it downloads onto their computer. Progressive streaming files do not adjust to match the bandwidth of the viewers’ connection like realtime streaming format do.

[edit] 10.4 Q to T

QDesign Music Code: A Quicktime audio codec for a low bandwidth connection.

QuickTime: A software architecture for displaying and manipulating time-based data (such as video and audio) on a computer.

RCA Connector (Phono): A small, single prong connector most commonly used to carry composite video and unbalanced audio signals.

Realtime Streaming: Technologies that match the bandwidth of the media signal to the viewers’ connection so that the media is always seen in realtime.

Real Media: A special streaming video and audio architecture created by Real, Inc.

Recompress: The art of compressing an already compressed file into a new format. Repression of material that is already highly compressed should be avoided if at all possible, as it would result in further degradation of the movie.

RGB (Red Green Blue): The colour space commonly used on computers. Each colour is described by the strength of its red, green and blue components. This colour space directly translates to the red, green and blue phosphors used in computer monitors. The RGB colour space has a very large gamut; meaning is can reproduce a very wide range of colours.

Sample: A measurement of a signal level at one specific instant in time.

Sample Rate: The accuracy with which sound is recorded. Generally, audio sample size is 8 or 16-bits. The latter is more accurate and provides more dynamic range, but takes up more storage space.

Saturation: The amount of colour in the video signal.

SECAM: SECAM is the broadcast television standard for France, Russia and much of eastern Europe.

Sequence: An assembly of shots edited together.

Sharpening: In a video camera, a special algorithm that is applied to the video image to make it sharper. With too much sharpening, strange artefacts will appear in the image.

Shutter speed: The speed of the rotation of the shutter inside the lens, measured in rotations per second.

Shutter: In a camera, the shutter opens and closes to control how long the focal plane is exposed to light. There is no physical shutter in a video camera, instead the camera’s CCD samples light for an appropriate length of time, and then shuts off.

Single-chip: A camera that uses a single CCD to gather all three (red, green, and blue) of the signals that will be used to create a full-colour image.

SMIL (Synchronised Multimedia Integration Language): This language enables the synchronisation of media and actions within a web page in addition to video and audio. SMIL can control the precise moments when certain options become available, or when certain items begin to play.

Sorenson Video Codec: A widely used high-quality, low bandwidth video codec, available in Quicktime products.

Spatial Compression: A compression method that removes redundant data within any given image.

Streaming video: Video that is downloaded, on-demand, iteratively to the viewer’s computer.

Streaming: The network delivery of media. This may refer to technologies that match the bandwidth of the media signal to the viewers’ connection, so that the media always appears as real time, while also referring to progressive or fully downloaded streaming where the media is downloaded entirely before beginning to play.

Symmetric Codec: A codec that encodes and decodes video roughly the same amount of time. Live broadcast and teleconferencing systems generally use fairly symmetric codecs in order to encode the video in realtime as it is captured.

TCP (Transfer Control Protocol): The common network protocol used widely on the World Wide Web.

Telecine: A film-to-video conversion system that introduces the 3:2 pull down necessary to compensate for the differences in frame rates between film and video.

Telephoto lens: A lens with a very narrow field of view (and, therefore, a long focal length). Telephoto lenses magnify objects in their field of view. Typically, lenses with focal lengths greater than 70 mm (equivalent to a 35mm film camera) are considered wide angle.

Temporal Compression: Video compression that compares the frames and only transmits the differences between them.

Three-chip: A camera that uses three separate CCDs to gather separate red, green, and blue data.

Timeline: A chronological display of an edited sequence in a non-linear editing system.

Tracks: The separate media types that make up a final movie. Most movies include a video track and an audio track.

[edit] 10.5 U to Z

Upload: The process of moving a file from a computer to a server (Commonly using FTP).

USB (Universal Serial Bus): A standard for attaching serial devices such as keyboards, disk drives, and some types of storage. At the time of this writing USB video capture devices were just becoming available.

Variable Bitrate (VBR) Encoding: A two-pass process of analysing and then compressing movies into an optimal data rate.

Variable Frame Length Movies: A movie that contains frames that are not all of equal duration.

VCD: Video compact disc. A format for storing 70 minutes of full-frame, full-motion, MPEG1 compressed video on a normal compact disc or recordable compact disc.

Vector: Multimedia formats that store graphical information as mathematical algorithms instead of pixels. These images do not have any pixels, but are equations describing the objects portrayed. Vector images scale perfectly to large and smaller sizes.

Video Buffer Verifier: A tool used to emulate the data buffer size on an MPEG player so the stream plays smoothly.

Video for Windows: Also called AVI, Microsoft’s initial multimedia architecture primarily aimed at CD-ROM video.

Widescreen: PAL video uses an aspect ratio of 4:3. Most film features are shot in a wider-screen aspect ratio. Some cameras include an option for shooting in a 16:9 aspect ratio. However, these modes are not actually any wider. Rather, they are just copped 4:3 images.

XLR connectors: Three-pronged, balanced audio connectors for connecting mics and other recording equipment.

Y/C video: Also called S-video (short for separate video), Y/C video has separate luma (Y) and chroma (C) video signals. (See also component video and composite video.)

[edit] 11 Appendix II: Online Points of Reference/Interest

Learning Technologies Group: http://www.oucs.ox.ac.uk/ltg/

Computer Video Magazine Self-Help Forums: http://www.computervideo.net

The Digital Filmmaker’s Resource Site: UK http://www.2-pop.com UK

Low-Budget Filmmaker E-Mail List: http://www.shootingpeople.org

WebMonkey Multimedia Tutorials: http://www.webmonkey.com/multimedia