Metropolitan Community College Audio Video Production Engineering Part 2 Video Rev. 6c.
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Transcript of Metropolitan Community College Audio Video Production Engineering Part 2 Video Rev. 6c.
MetropolitanCommunityCollege
Audio Video Production EngineeringPart 2 Video
Rev. 6c
Start Week 7
2
Video and Vision
The Human EyeCorneaLensRetina
Optic Nerve
3
Detailed Information
http://www.photo.net/photo/edscott/spectsel.htm#01
4
Human Eye
www.photo.net5
Human Eye Detail
6
Additional Fovea Details
http://en.wikipedia.org/wiki/Fovea
7
More Vision Detail
http://hyperphysics.phy-astr.gsu.edu/hbase/vision/rodcone.html
8
Rods and Cones
www.photo.net9
Visible Light Spectrum
Measured in WavelengthUnit of measure nm
(nanometer)Approx. 400 nm – 700 nm
10
Spectrum
www.photo.net
11
Visible Spectrum
www.photo.net
12
Spectral Sensitivity of Human Eye
www.photo.net13
Adjusted Spectrum
www.photo.net14
Low Light “Rods”
www.photo.net15
www.photo.net16
Color Temperature
Characteristic that can change our perception of color/hue
17
www.photo.net18
Color Temperature
www.photo.net19
Relative intensity has been normalized for each temperature (in Kelvins).
20
Color Temp & Light Source
1000-2000 K Candlelight2500-3500 K Tungsten Bulb (household variety)3000-4000 K Sunrise/Sunset (clear sky)4000-5000 K Fluorescent Lamps5000-5500 K Electronic Flash5000-6500 K Daylight with Clear Sky (sun overhead)6500-8000 K Moderately Overcast Sky9000-10000 K Shade or Heavily Overcast Sky
21
White Balance
22
Lens filter setting
Select the FILTER according to the lighting condition.
Position 1 (3200K) : For shooting indoors with studio lighting
Position 2 (5600K + 1/8ND): For shooting outdoors.
Position 3 (5600K + 1/64ND): For shooting outdoors under a clear sky.
23
White Bal Adjustment1. Set the following switches.• Set the OPERATE switch to ON.• Set the OUTPUT switch to CAM-AUTO
KNEE OFF.• Set the IRIS mode switch of the lens to A
(Auto).2. Set the FILTER knob according to the
current lighting.3. Set the WHT.BAL switch to A or B.
24
4. Place a white object near the center of the screen under the same lighting conditions as the target subject and zoom in to fill the screen with white.
5. Tilt the AUTO WHT./ACCU FOCUS switch upward (to AUTO WHITE) once and release it. "AUTO WHITE A, B OPERATION" is displayed in the viewfinder while the auto white balance adjustment circuit operates. When the white balance has been adjusted correctly, the approximate color temperature is displayed together with “AUTO WHITE A, B OK” for about 5 seconds.
25
Television Lighting
There are several different Lighting instrument types.
Applications vary depending on program needs.
26
Fresnel with barn doors
27
Flood light, focusing
28
Softlight
29
Broad light withBarn Doors
30
Scrim
31
Basic Three Point Lighting
Three point lighting video
32
The Television Picture
NTSC RS-170A standard(standard def.)
33
Horizontal Sync
34
Color Framing
35
Time Code
Considered to be a system of identifying locations of images or sound on recorded medium (film, tape, etc.)
36
Time Code Types
ProprietarySMPTE (LTC)SMPTE VITCEmbedded digitalMIDI
37
Usage Considerations
SMPTE standard will be used for discussion Additional detail:
http://en.wikipedia.org/wiki/Drop-frame_time_code
38
Time Code Structure
80 bit digital contentHour, minute, second,
frame, and other info.
39
Timecode Data Structure
Bits Definition Bits Definition
0-3 Frame units 32-35 Minute units
4-7 User bits group 1 36-39 User bits group 5
8-9 Frame tens 40-42 Minute tens
10 Drop frame flag 43 Binary group flag 0
11 Color frame flag 44-47 User bits group 6
12-15 User bits group 2 48-51 Hour units
16-19 Second units 52-55 User bits group 7
20-23 User bits group 3 56-57 Hour tens
24-26 Second tens 58-59 Binary group flags 1 and 2
27 Biphase mark correction 60-63 User bits group 8
28-31 User bits group 4 64-79 Sync word
40
Non-Drop Frame
Non-drop frame needed for digital video medium where each frame needs identification
Running time not accurate
41
Drop Frame
Mainly used when accurate running time is desired
Drops numbers each minute on the minute except on 10th minutes
42
NTSC Color Signals
Have an actual frequency of close to 29.97 frames-per-second. As cue points must be located at frame boundaries, this figure is normally rounded up to 30 frames-per-second, causing an excess of 108 frames per hour.
43
To Eliminate These 108 Frames each HourTwo specific time code
frame values are dropped each minute (2x60=120), except every 10th minute (2x60-2x6=108).
44
Time Code Values Dropped
Are specified as the first two frames of a minute. Thus, the time code number following 01:04:59:29 would be 01:05:00:02, time code frames 01:05:00:00 and 01:05:00:01 don't exist.
45
Non-linear Editor Note:
non-dropframe timecode values as HH:MM:SS:FF and dropframe values as HH:MM:SS;FF
46
VITC
Time code encoded into the video frame
Can be read while in still frame
Replaced in editing process
47
Audio & Synchronizing
When used in audio or sweetening for video (layback) resolution uses ATR Tach. Usually 100th of a frame of video
48
TC Switch Functions
REC :Preset mode. Set to this position when newlypresetting and recording the time code. The timecode mode of the time code generator will be inthe REC run mode (time code runs only duringrecording).This position allows you to record continuous timecodes when recording scenes one after another.
49
TC Switch Functions
FREE :Preset mode. Set to this position when
newly presetting and recording the time code. The time code mode of the time code generator will be in the FREE run mode (time code runs permanently).
Select this setting when the unit should be slavelocked with an external time code generator.
50
TC Switch Functions
REGEN :Regeneration mode, in which the unit
reads existing time codes on the tape and records time codes in continuation of the existing ones. Set to this position when you want to add additional time codes to time codes already recorded on the tape.
51
Time Code Info (16)
52
TC input/output (4&5)
53
TC Input
Input connector for the SMPTE-standard LTC signal. The built-in time code generator can be slave-locked with the input time codes.
If the user’s bits should also be slave-locked, set the VCR Setup Menu item No. 403 U-BIT SLAVE to “TC&UB”.
54
* When the TC GENE switch (#17 on page 15) is set to REC or REGEN, or the VCR Setup Menu item No. 398 SSF MODE is set to “CUE MODE” or “MARK MODE”, slave-locking will not take place. For the slave lock of time code, see page 64.
55
Time Code Menu
56
End Week 7
Review week 8
57
Basic TV Principles
Video – The visible portionSync – The housekeeping
portion
58
Cameras and Monitors
Many types of camera pick-up sensors (tubes, CCD, CMOS)
Many display types (tubes, LCD, Plasma)
59
Image Capture
Some type of scanning is required
Photo sensitive surface is required
60
Image Capture
CCD (Charged Coupled Device) is a passive-pixel sensor
Requires a separate image processer
61
Image Capture
Active-Pixel Sensor (aps) or CMOS uses less power than CCD, has less image lag and is less costly
Image sensor and image processing on same chip
62
Basic Block DiagramCCD
CCD pick up
TimingGenerator
Digital SignalProcessor
FIFORegister
(DSP)
Encoder
EEPROM
Memory
Image
Video ImageOut
63
Basic Block DiagramTube pickup
Pick up TubeX 3 (R G B)
Synchronizingand Sweep
H & V
Amps ProcessingBalance
Encoding
LensControl
Image
Video Image
Genlock
64
Encoding
The process of combining raw image information into a useable format for display such as NTSC, S VIDEO, Component and RGB.
65
NTSC
National Television Standards Committee
Analog standard in USAAlso called composite video
66
S Video
Two wire systemLuminanceChromaImproved video quality
67
Component
Y, R-Y, B-YHigh quality broadcast
recording
68
RGB
Red, Green, BlueHigh Quality Broadcast and
computer imagesSync on Green or separate
Horizontal & Vertical Sync
69
Lens1 FOCUS ringManual focus ring.2 ZOOM lever/ringThis is the manual zoom ring equipped with a zoom lever.To adjust the zoom manually, turn the zoom mode knob 12 to position "M".3 IRIS ringManual iris ring. To activate the auto iris feature, set the IrisMode switch 7 to A.4 [VTR] Trigger buttonTo start/stop shooting.
70
5 [RET] return video button• When GY-DV550 is in the record-pause or stop mode, press this button to check the immediately preceding image recorded.• When the camera control unit is connected, the return video signals can be monitored on the viewfinder while pushing this button.• When an external VCR is connected, the return video and return audio signals can be monitored while pushing this button.(When VTR SELECT switch is set to EXT.)6 ZOOM servo control leverTo operate the servo zoom feature with this lever, set the ZOOM knob 12 to S.• Pressing the W section of this lever increases the angle of the lens for a wider shooting angle.• Pressing the T section of this lever narrows the lens angle perspective for telephoto shots.• Pushing harder changes the speed of the zoom.
71
7 IRIS mode switchA: Activates the auto iris feature.M: Allows manual iris control.8 Momentary auto iris buttonWhen the IRIS MODE switch 7 is at "M", pushing this button activates the Auto Iris Function while it is held down only.9 [S] IRIS speed adjusting control For adjusting the iris operation speed.
Under exposed is better than over exposed for HDTV!
72
10 FILTER threadProtect the lens with a clear filter or UV filter by screwing the filter onto the thread inside the lens hood from the front. Other filters can be used for various effects.11 ZOOM servo connector Connect an optional zoom servo unit here.12 ZOOM mode knobS: Servo zoom mode. Allows operation by the zoom servo control lever 6. M: Manual zoom mode. Allows zoom control by the zoom lever/ring 2.13 BACK FOCUS ring/fixing screwFor back focus adjustment only. Secure with the screw knob after adjustment.
73
14 Macro focusing ring (for close-up shooting)By rotating this ring in the direction of the arrow, close-up
shooting of very small objects becomes possible. Normal focus adjustment and zooming are not available in the macro mode. To shoot images in the macro mode, set the focus ring 1 to the infinite position and the zoom ring 2 to the maximum wide-angle position. To adjust the focus of the macro image, rotate this ring in the direction of the arrow until the object is focused.
74
Back Focus Video
www.dvinfo.net/store/prohd/video11.html
75
Resolution
Horizontal resolutionVertical resolutionPixelsBandwidth dependant
76
Resolution Chart
77
Viewing Information
http://forum.blu-ray.com/showthread.php?t=33462
recommended farthest sitting distance to see full resolution for each screen size is…
78
For DVD (480)
20 inch TV= 7 feet26 inch TV= 9 feet30 inch TV= 10.5 feet34 inch TV= 12 feet40 inch TV= 14 feet50 inch TV= 17.5 feet60 inch TV= 21 feet.
79
For 720 HD sources
20 inch TV= 4 feet26 inch TV= 5 feet30 inch TV= 6 feet34 inch TV= 6.7 feet40 inch TV= 8 feet50 inch TV= 10 feet60 inch TV= 12 feet
780
For 1080 HD sources
20 inch TV= 2.8 feet26 inch TV= 3.5 feet30 inch TV= 4 feet34 inch TV= 4.5 feet40 inch TV= 5.3 feet50 inch TV= 6.5 feet60 inch TV= 8 feet
81
82
Monitors and Receivers
RFAMPMixerLocal Osc
TunerAnt.
VideoIF Amps
VideoDet.
AudioIF Amps
AudioDet.
Video AmpChroma processing
AudioAmp
Speaker
Audio In
Video In
SyncSep & Amp Horiz.
Sweep
VerticalSweep
High Voltage
Picture tube
Deflection
83
Inputs
Video (all types)RFDigital
84
Display
CRT (cathode ray tube)Flat screens (LCD & Plasma)Projection (LCD & DLP)
85
Display
LCD (Liquid Crystal Display)Not the best for fast moving
images (greatly improved since 2009)
Accurate black display difficult
86
Display
LED back lit LCDEdge lit…blacks not as evenFull array…better black
levels with little light leakage
87
Display
Plasma long life, good viewing angle and good brightness
Subject to image burn-in
88
DLP (Digital Light Processing)
Better suited for projection than flat screen.
Requires a lamp and has narrow viewing angle when used as flat screen
89
Interlaced Scanning
Produces odd lines first then even lines each takes 1/60th second (field)
Two fields make complete frame (1/30th sec.)
90
Progressive Scanning
All lines are progressively scanned starting with line one, then two, three, etc.
The refresh rate can be higher than interlaced scanning often 1/60th sec.
91
DTV Systems
480p 480 active scan lines 1/60th Sec.
720p 720 active scan lines 1/60th Sec.
1080i 1080 active scan lines 1/30th Sec.
92
Refresh Rates above 60
Applies to LCD displays.Improves a jerky appearance
called “Judder”. 120 Hz & 240 Hz refresh cuts down on motion induced artifacts.
93
Refresh Rates
The use of 120 & 240 Hz refresh rates causes unwanted background noise and can cause a lack of depth in the images.
94
End week 8
Review Week 9
95
Measurement & Wiring
Waveform monitorVector scopeMany new equipment types
since HD introduced
96
New Test Equipment
http://www.tek.com/testimonial/benefits-waveform-monitors-color-correction-video(6:05)
97
Broadcast Specs
http://www.tek.com/how/editing-compliance-broadcast-specifications(6:43)
98
Color Grading HD
http://www.tek.com/how/art-color-grading-scopes?utm_source=epiphany&utm_medium=email&utm_campaign=eNewsFebruary2013(27:52)
99
Camera Alignment
http://link.brightcove.com/services/player/bcpid424610616001?bctid=1155879794001(8:51)
100
Video Links
Waveform Monitor videoVector scope videoMonitor setupApplying WFM & VSGrey Card
101
Tektronix link102
Grey Bar
Tektronix link103
Tektronix link104
External Reference
Needed to compare timing and phasing
Needed to lock signals to same reference (genlock)
105
External ReferenceMostly “Black Burst or Tri-
Level Sync” is used as the reference signal.
A single “Master” generator is used and the signal split using VDA and sent to other equipment.
106
107
External Reference
For Waveform Monitor and Vectorscope, the reference signal is connected to “Ext. Ref. In”. It has to be selected using the “int/ext” reference switch.
108
External Reference
For use in a camera/switcher chain, the reference signal is applied to the “Genlock” in connection.
109
Wiring and cable
Impedance75 ohm standard
Wiring must always look at 75 ohm load (terminated)
110
Looping
Method of connecting more than one device from a single feed
Cable lengths must be shortLast device must be
terminated111
Looping Example
112
Video Connectors
Depends on type of video signal ( comp. , S, etc.)
Standard Professional is BNC (old type UHF)
Consumer often use RCA
113
Common Connectors
S video RCA BNC
HD-15 (VGA) DVI (digital) HDMI (High Def)
114
Cable Types and Loss
Cable selected for application
Short length may use smaller diameter cable
Long length use RG-6 type
115
Cable Construction
Center conductorDielectricShieldOuter jacket
116
Coax Cable Construction
117
Cable Loss
Loss per foot increases as cable size decreases
Loss greatest at high freq. Resulting in lack of picture definition (detail)
118
Cable Types
Video double shielded (RG6 type), .305” diameter, 75 Ohm, 98% Shield, VOP 66%, loss/C 1MHz .25dB, 10MHz .78dB
119
Cable Types
Video single shielded (RG59 type), .242” diameter, 75 Ohm, 95% Shield, VOP 78%, loss/C 1MHz .3dB, 10MHz .9dB
120
Cable Types
CATV Double shield(RG59 type), .237” diameter, 75 Ohm, 100% Shield, VOP 82%, loss/C See chart
121
Cable Types
CATV Double shield(RG6 type), .275” diameter, 75 Ohm, 100% Shield, VOP 82%, loss/C See chart
122
Loss Per Hundred Ft.Ch 2 54 MHzCh 13 216 MHzCh 36 300 MHzCh 62 456 MHzCh 80 872 MHzCh 158 1002 MHz
123
124
End Week 9
Review Week 10
125
Distribution, Switching, and RecordingDiscussion
126
Distribution
Video distribution amplifier VDA
Amplifier that provides usually 4 – 6 isolated outputs from one input
127
Equalizing
Equalizing may be stand alone or part of a VDA
Compensates for long video cable runs
Multiburst test signal usually used.
128
Multiburst Test Patern
129
Normal Response
130
High Freq. Loss
12331
High Freq. Peaking
132
Routing Switchers
Sometimes called cross-point switchers.
May have many inputs and many outputs.
Often use electronic control panels
133
Routing Switchers
May be build into equipment to provide “Input” selection or stand alone unit to provide a mechanical way to select a signal to send to a destination (1 x 10, 6 x 2, etc.)
134
Switching (Production)
Signals must be synchronous
Non-synchronous signals processed with frame synchronizer (built in)
135
Ross Prod. Switchers
http://www.rossvideo.com/production-switchers/vision/models.html
136
Timing
Signals must be timed (adjusted) so leading edge of sync is the same for all inputs.
137
138
Phasing
Subcarrier phase must be adjusted to the same value for all signals.
Do not confuse with Burst Phase
139
1400
Dissolve, Wipe, Key
Switcher has a number of buses
Two paired buses may mix signals in a number of ways
141
Dissolve
The process of replacing one signal with another
During the transition both signals are present
142
Wipe
The process of replacing one signal with another
The two signals are separated by a pattern one signal on one side the other on the second side
143
Key
Luminance keyChroma keyMat keyExternal key
144
Luminance Key process
Electronic circuits detect adjustable luminance levels of the video signal and creates a cut-out signal that is filled with a second video
145
Mat Key process
Electronic circuits detect adjustable luminance levels of the video signal and creates a cut-out signal that is filled with a color produced by the mat generator.
146
Chroma Key process
Electronic circuits detect adjustable chroma values of the video signal and creates a cut-out signal that is filled with a second video
147
External Key process
External device (like a CG) that provides a key signal (cookie cutter) as well as a fill signal. The key signal cuts a pattern out of the primary video signal.
148
Transitions & MovesVideo Transitions 5:10https://mccneb.ensemblevideo.com/app/plugin/embed.aspx?ID=nePspdTVvEGXfEBfDgjNBw
Camera Lens Adjustments 4:18https://mccneb.ensemblevideo.com/app/plugin/embed.aspx?ID=_DXLd6a3mk65OpbqI7H7CA
Camera Movements 4:00https://mccneb.ensemblevideo.com/app/plugin/embed.aspx?ID=iWG_rnKMNEC8bLAHLejbAA
149
Recording
Similar to audioUses both stationary and
rotating headsMany formats
150
Video heads
151
152
Heads
Stationary heads used for audio and control track
Rotary heads used for video erase and record/playback
Some have stationary erase head
153
Tape formats
BetaCamVHS and SVHS¾” U-Matic1” type COther consumer types
154
Playback
Tracking (control track)Slow motionTime base correctionDropout compensation
155
End Week 10
156
Digital Video
Process similar to audioSample rate often 4X SCSync is not sampled coded
word contains sync infoRequires high bandwidth
157
Storage medium
DV tape recorderHard DriveVCD/DVDOther professional formatsSD type cards
158
Antialiasing
Low pass filtering necessaryBlurry glass used to add a
small blur to image
159
A to D conversion
Analog signal from sensor is converted to digital and sent to DSP
160
Other processes
Matrix for colorimetry and white balance
GamaChroma SubsamplingSharpening
161
Compression
Type of compression depends on use of media
StoredTransmittedTransmission medium
162
Compression Basics
Uncompressed NTSC720X480 using 4:2:2 YCrCbAt 30 FPS Requires 165 Mbps
163
Compression Basics
Used to reduce file size or transmission bandwidth
Most types are based on retaining static image segments and transmitting motion
164
Type of Compression
MPEG 1 and 2MPEG 4JPEGH.261, 263, 264 for packet
switched networksOthers
165
Improving fine motion detailH.263 and others use Block
sizes of 16X16 or 8X8H.264 and Windows Video 9
CODEC (WMV9/VC-1) use 4X4
166
8X8 vs 4X4
167
DV Format
Use 8 bits (0 – 255)Black is 16White is 235
168
Setup (pedestal) on DV
Europe and Asia use 0 for black
USA uses 7.5 IRE for blackMenu selected for analog
out (0 or 7.5)
169
DV Sampling
Same rate as D1, D5, Digital Betacam
720 Pixels per scan lineColor sampled at ½ rateHence 4:1:1 for 525 line
(NTSC)170
DV Compression
Uses Intraframe CompressionDoes not depend on
preceding or following frames
171
DV Compression
Uses Adaptive Interfield compression
If little difference in two interlaced fields are detected it will compress them together
172
DV Compression
5:1 compressionDV Video 25 megabit/secSound 1.5 Subcode & Error corr. 8.7Total data stream about
35.382 megabit/sec173
File Format Conversion
174
Prism features
Prism lets you set compression/encoder rates, resolution and frame rate of output files. Prism supports everything from HD to high compression for smaller files. You can even set a specific size for output files.
175
File format conv. from
.avi .asf .mpg .mpeg
.mpe .vob .mov .3gp
.mp4 .m4u .flu .mku
.mod .ogm .divx .dv(Both Windows & MAC
format)176
File format conv. to
.avi .wmv* .asf* .mpg
.mov .3gp .mp4 .flu
.swf .rm* .gif* .dv
.mp3 .wavBoth Windows and Mac
format (except *)177
Menu Options
178
Menu Options
179
USB 1 and USB 2
Rely on host processorsUSB 1 speed of 1.5 Mbit/sUSB 2 speed of 480 Mbit/sMost USB 2 devices run at
240 Mbit/s
180
Cable Lengths
USB 1 & 2 16’ (up to 5 active extensions)
USB 3 9.8’ (active cable available 65’)
1394 15’ (new type 32.8’)
181
Power available
USB 1 100 maUSB 2 100 maUSB 3 150 ma1394 1.5 A 45 wattsThunderbolt 10 watts
182
1394 Firewire
Brand names for 1394FireWire – Apple Inc.i.LINK – SonyLYNX – Texas Instrument
183
Firewire
More used than USB2 as it does not need computer support and has higher speed (400 Mbit/S)
184
Firewire Connectors
4 Pin does not have power 6 pin does have power
185
Firewire
1394c amendment will support 800Mbit/sec for 100 m of CAT 5 cable Approved June 12, 2008
186
Thunderbolt Information
http://www.apple.com/thunderbolt/
187
Comparing I/O Speeds
188
Resources
http://en.wikipedia.org/wiki/Firewire
189
Discussion
QuestionsFeedbackSuggestionsOther
190