Video Basics 8 - Chapter 11
video server
A large-capacity hard-drive array that can ingest, store, and play back a great amount of audio and video data. It can be accessed by several users simultaneously.
memory card
A read/write solid-state portable storage device that can download, store, and upload digital audio and video information.
field log
A record of each take during the video recording.
frame store synchronizer
Image stabilization and synchronization system that has a memory large enough to store and read out one complete video frame. Used to synchronize signals from a variety of video sources that are not locked to a common sync signal.
SD Card Record Protection
SD cards have a movable tab that prevents accidental erasure. The card can be read in the down (locked) position but will write (record) data only when the tab is in the upper (unlocked) position.
pocket recorder
Small camcorder, such as a smartphone, that fits into a shirt pocket. Records exclusively on memory cards. Also called mobile media.
Hard Drives
Some camcorders use hard drives as their video recorder (VR). In concert with data compression, even small hard drives can record a relatively large amount of video and audio. Even if a hard drive is encased in a cassette, however, it is susceptible to shock and extreme weather conditions. This is why memory cards are the preferred recording media for camcorders and portable VRs.
ATSC
Stands for Advanced Television Systems Committee. Sets standards for digital television transmission over terrestrial, cable, and satellite networks. ATSC replaced NTSC as the television analog standards committee.
AVCHD
Stands for Advanced Video Codec High Definition. A signal compression used in consumer HD camcorders that allows burning high-definition video to standard DVDs.
codec
Stands for compression-decompression. Can be one of several compression systems of digital video, graphics, and audio files.
DVR
Stands for digital video recorder. You can use your iPhone to capture HD pictures and sound; or, assuming you have the appropriate software, your laptop computer can serve as a high-quality recording device. DVRs provide you with features that are not readily available on a laptop and that speed up your workflow, from video capture to editing your footage.
Studio DVRs
Studio DVRs are used to record in-house productions and large EFPs. They are often the primary recording unit, with the larger servers providing the recording backup. Much like smaller DVRs, they vary in recording capacity, storage media, codecs, and file formats. Most DVRs use solid-state devices as recording media or high-capacity hard drives. This digital video recorder has two removable solid-state drives for recording and playing back high-definition video and audio. The two drives can record simultaneously for backup or sequentially for longer programs. The operating controls are modeled after traditional videotape recorders.
Clapboard
The clapboard is used for each take and contains the necessary information for locating clips in postproduction. The movable clapstick is snapped closed to synchronize the video and audio of each take.
Field Log
The field log is kept by the VR operator during large productions. It normally indicates the production title, names of producer and director, recording date and location, media number, scene and take numbers and their sequence, whether the takes are good, VR time code number, and what the take was all about.
ingest
The importing and capturing of video and audio data files on a hard drive, usually a server. See also capture.
Character-Generated Slate
The slate gives vital production information and is recorded at the beginning of each take.
Video Leader
The video leader helps identify content and adjust the playback to the original video and audio values.
Read/Write Optical Discs
These laser-operated optical discs let you read (play back) previously recorded material and write (record) new material, just like with a hard drive. In camcorders these optical discs are encased in cartridges, which protect the delicate laser mechanism enough to make the laser media relatively rugged and immune to heat, moisture, and rough camera handling. Again, the maximum recording time depends on two major factors: whether you record your scenes raw, in 1080i HDTV or a lower-scan digital format, and on the capturing frame rate.
Self Contained Portable DVR
This small portable DTE DVR can capture up to 30 frames per second in 1080p (progressive scan) resolution. The touch screen serves as an input video monitor with four channels of audio metering.
SD Memory Card
This solid-state device can record and store a great amount of digital video and audio data.
Portable DVRs
To extend the recording capacity of a camcorder, you can connect it to a portable DVR. Some recorders that can capture raw footage can be plugged right into the camera; others are connected to the camera via cable. This high-capacity recorder plugs onto the back of a high-end 4K Sony camera.
capture
Transferring video and audio from the recording media to the hard drive of a computer with an editing program. See also ingest.
Video Stabilization
Video stabilization is necessary to prevent picture breakup when switching to live video inserts, such as during a newscast or back to the live sporting event after a commercial break. In this case, you may sometimes see the picture break up into different parts and even freeze for a moment until it shows the normal action again. But how can the action temporarily freeze when the telecast is live? The reason is that even if a program is broadcast live, each frame is temporarily recorded and, if necessary, corrected before it is sent to your television receiver.
video leader
Visual and auditory material that precedes any color video recording. It consists of a 30- to 60-second recording of color bars and a 0 VU test tone, an identification slate, circled numbers 2 and 1 that flash on-screen each second, and finally another second of black before the first frame of the program video. Also called academy leader.
Digital Recording Systems
ll video-recording systems operate on the same general principle: the digital video and audio signals are recorded on some kind of electronic storage device that allows playback in a specific order on demand. The systems vary greatly, however, in terms of the recording and storage media.
Checklist: After Video Recording
- Recording Check - Before moving on to the next scene or striking the studio set or remote location, verify that you have actually recorded the scene as planned. Go to the beginning shot, then fast-forward two or three times to spot-check the entire recording. Pay attention to the sound. Sometimes you may think that the audio distortion is in the playback equipment, but more likely than not the problem was caused during the production by connecting the incoming sound signal to the wrong mixer input (line instead of mic or vice versa) or by overloading the incoming digital audio. - Labeling - Label each recording media with the title of the production, the recording date, the media number, and its content. Label the box with the identical information. As trivial as such labeling seems, countless precious hours of postproduction time have been lost because someone labeled the media boxes but not their content. Watch that the media labels match the information on the corresponding field log. Preparing Recorded Material for Postproduction - As soon as possible, copy all recorded files and use verification software to make certain that the copies are identical to the source files. This is the time to add such metadata as shot location, names of people, codex, and the like. For irreplaceable onetime-only footage, such as a documentary on the first climb of a difficult Himalaya peak, you can further protect your recording by storing the raw files or original video on separate drives and, for good measure, with a different codec for each file.
Checklist: Before Video Recording
- Schedule - Most likely, your operation will have more than one type of video recorder available. Be reasonable in your request. You will find that VRs are usually available for the actual production or the remote shoot but not always for your playback demands. - VR Status - Always do a brief test recording and play it back before the actual video capture. Sometimes one of the tiny switches on the VR may be in the wrong position, preventing you from recording either video or audio. - Power Supply - Electronic image stabilization, which corrects minor camera wobbles, and using the foldout monitor and the camera light also rapidly drain the battery. If you use household current for power, you will need the appropriate adapter. Check whether the connectors of the power cable fit the jacks of the power supply and the camera. Don't try to make a connector fit a jack for which it isn't designed; even if you can force it in, you may blow more than a fuse. - Recording Media - Although your camcorder may use a memory card for recording, not all memory cards are alike. Some memory cards may look the same but won't fit the slot in the camcorder. Don't rely simply on the label on the box. Open it and see whether it contains the correct media. Check the card's storing capacity. A low-capacity SD card may be good for quite a few still shots but may not have enough storage space for a longer video shoot. - Cables - The problem with defective cables is that ordinarily, you can't see the damage. If you don't have time to test the cables beforehand, take some spares along. As you recall, most professional recorders and camcorders use XLR jacks for audio inputs, but some may have RCA phono jacks. Video cables have BNC or RCA phono connectors. As you know, computers have their own interfaces (cables) that do not always connect to the electronic video equipment. Keep a supply of adapters on hand, but always try to have cables with the correct plugs; each adapter is a potential trouble spot. - Monitor - Most portable monitors can be powered by battery or household current. When using such a monitor on an EFP, bring a long extension cord as well as two fully charged batteries. You can feed the camera output directly into the monitor via a coaxial cable with a BNC or an RCA phono connector at both ends. Some small video recorders have a monitor attached to them.
Checklist: During Video Recording
- Video Leader - Whenever possible, start each video recording session with a video leader, which consists of a 30- to 60-second recording of color bars and a 0 VU test tone, an identification slate, circled numbers 2 and 1 that flash on-screen each second, and finally another second of black before the first frame of the program video. - Recording Time Readout - Most VRs stamp each frame automatically with some kind of time code or address, which is shown on the digital time readout of the VR. This enables you to quickly locate the approximate starting point when asked for a playback. Most professional VRs show hours, minutes, seconds, and elapsed frames. - Recording Levels - Watch carefully the recording levels of the video and especially the audio. You may get so caught up in the exciting visuals of a scene that minor—or even major—audio problems escape your attention. Many camcorders indicate these levels in the viewfinder display or on VU meters on the video recorder. Note that the volume standard for digital audio is considerably lower than that of analog. In any case, the digital audio signal should never peak above 0 dB, or you will end up with irreparable sound distortion. - Recording for Postproduction - When recording for postproduction editing, record enough of each segment so that the action overlaps the preceding and following scenes. Such trim handles (also called pads and edit margins) greatly facilitate editing. If you have enough media, record the camera rehearsals. Sometimes you will get a better performance during rehearsal than during the actual take. Record a few seconds of black after each take before stopping the VR. This run-out signal acts as a pad during editing or, if you do a live recording, as a safety cushion during playback. - Retakes - As the VR operator, tell the director right away if you feel that another take is necessary for some reason. It is far less expensive to repeat a take than to try to "fix it in post." Be ready to locate the first few frames before the flawed take without undue delay. You can do this quite easily if you keep an accurate field log. - Recordkeeping - Keep accurate records of each take during the recording. A carefully kept field log can save you considerable time in finding takes during the field production and especially when preparing a more accurate VR log in the postproduction phase.