2/17/20101
Troubleshooting HD Video Throughout Broadcast Chain
Karl KuhnSr. Video Application [email protected]
2/17/20102 =22
Television Signal Formats--- Tektronix
Matrix
CompositeEncoder
A to DConv
Serializer
R
G
B
270MHz
Y
R-Y
B-Y
6.75MHz Sample
Rate for B-Yand R-Y
13.5MHzSample
Rate for Y
Serializer
Clock X10
ITU-R BT.601-2Serial DigitalComponent270Mb/sec
YR-YB-Y
10 Bits Parallel
ITU-R BT.601-2Parallel Digital Component27MB/sec
Serial Digital Composite143Mb/sec (NTSC)177Mb/sec (PAL)
Parallel Digital CompositePAL=17.7MHz
NTSC=14.3MHz
Multiplexed 27MB/secB-Y/Y/R-Y/Y/B-Y/Y
10 Bits Parallel
4Fsc(PAL=17.7MHz)
(NTSC=14.3MHz)
ComponentAnalog Video
(RGB)
Analog CompositeVideo(PAL/NTSC)
MPEG2ProgramEncoder
DVDDigital Versatile
(Video) Disk
A to DConv
Audio
Color DifferenceComponentAnalog Video(Y, B-Y, R-Y)
MPEG2 Protocol
Transport StreamTransmission
Channel
Tx
TransmissionChannel
RxMPEG2ProgramDecoder
MPEG2 Protocol
Transport Stream
Transmission Channel Analysis
GigE and/or Modulated RF Signals.
MPEG2 Protocol Analysis
PictureQuality
Analysis
SD and HD Digital Video
MPEG2 Protocol
Program Stream
Data
Data
Analog CompositeVideo (PAL/NTSC)
A to DConv
A to DConv
2/17/20103
Basic Anatomy of the human vision system
http://webvision.med.utah.edu/index.html
3 Color and Gamut Monitoring
� Physical part/elements– Eye, Lens and Retina
– Rods – Sensitive to Blue-green light
– Used for vision under dark-dim
conditions.
– Cones – 3 Types of Cones
Sensitive to either
long wavelengths of light (red light)
medium wavelengths of light (green light)
short wavelengths of light (blue light) – Optic nerve
2/17/20104 Tektronix Video Insight Seminar Series4
Technology evolutionNTSC Composite
BlankingLevel 0V,0 IRE
PeakWhite100 IRE
Horizontal Sync Pulse Color Burst
Horizontal Blanking Interval
Active Picture
Setup,Ref
Black7.5 IRE
2/17/20105 Tektronix Video Insight Seminar Series5
Picture Observation of the Digital Cliff
Digital signals are efficient, versatile and provide excellent quality.
Digital signals have strong noise tolerance…
But, be aware of the Digital Cliff
Please
Standby
2/17/201066
� Analog
– Degrades Gracefully
– Window into Electronic World
– You Decide
� Digital
– Cliff Effect
– Can’t See Ones and Zeros
– The Technology Decides for You
� Intensive Care Ward
� Big Circuit Board
� Need Right Tools
� Figure Pointing
� Never Any Funding
Analog vs. Digital
6
2/17/20107 Tektronix Video Insight Seminar Series7
SMPTE 292 Digital Horizontal Line
First active picture sampleLast active picture sample
COMPONENT: Active line digitized, EAV/SAV added
EA
V
SA
V
3F
F3
FF
00
000
0
00
000
0
XY
Z
XY
Z
0C
b
1Y
2C
r
3Y
3F
F C
3F
F Y
000
C
000
Y
00
0
C00
0
Y
XY
Z C
XY
Z Y
LN
0 C
LN
0 Y
LN
1 C
LN
1 Y
CR
C0
YC
R0
CR
C1
YC
R1
XYZ Word Conveys Start/End of Line (H),Vertical Blanking (V), and Field (F)
Analog Tri-level Sync
0mV
-300mV
+300mV
2/17/20108 Tektronix Video Insight Seminar Series8
Chromaticity
• Formats limit color range
• Care has to be taken when converting between formats
2/17/20109 Tektronix Video Insight Seminar Series9
Technology evolutionDigital Component
M
A
T
R
I
XDigitize
At this
point
2/17/201010 Tektronix Video Insight Seminar Series10
Component Waveform Overlay Mode
700
Tek
0
No IRE scale
it’s now a mV
scale 700mV
is now Peek
white.
No Reference
Black at 7.5
IRE,
Reference
Black is now
at 0mV
No Sync
Pulse as
such, it’s now
a Data word.
2/17/20101111
Gamut Monitoring — the traditional way
100% Bars
Y, Pr, Pb
White Gamut
Black
Gamut
2/17/201012 Tektronix Video Insight Seminar Series12
Component Color Difference
10-bit Quantizing
Excluded 399.2 mV 3FF 11 1111 1111
Max Positive 350.0 mV 3C0 11 1100 0000
Black 0.0 mV 200 10 0000 0000
Max Negative -350.0 mV 040 00 0100 0000
Excluded -400.0 mV 000 00 0000 0000
Pr Channel Pb Channel
2/17/201013 Tektronix Video Insight Seminar Series13
Impact of Distortions on Different Color Spaces
A signal can be legal in one color space but not valid when converted to another
Legal RGB
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
A
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
Converted back toRGB
D Illegal
Converted to LegalColor Difference
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
B
DistortedColor Difference
Legal
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
C
2/17/20101414
Gamut Monitoring RGB — Diamond display
RGBGamut
Configuration MenuSelectable Gamut Thresholds
2/17/20101515
Gamut Monitoring Composite — Arrowhead display
ChromaGamut
LumaGamut
Configuration MenuSelectable Gamut Thresholds
2/17/20101616
Transmission – Using the Arrowhead display
� Used with both live and test
signals
� Adjustable Alarm limits
� Can be used with SD and HD
content to determine Composite
legality
2/17/201017
New Spearhead Display (Color Lightness, Saturation and Value)
X(i) = max(i) - min(i)
Y(i) = [max(i) + min(i)]/2
50%
75%
25%
100%
75%
50%
25%
Value
Saturation (HSV)
Lightness
black
white
monochrome axis
50%
100%
25%
102% (limit)
0%
- 0.5%
105%
Spearhead triangular RGB Gamut space:
max(i) = maximum of r(i), g(i) , b(i);
min(i) = minimum of r(i), g(i) , b(i);
in mV.
The space is bounded by 3 lines:
1) the vertical line (monochrome) where
max(i) = min(i),
i.e. Y(i) = max(i) = min(i), X(i) = 0;
2) the line of all possible 100% Saturated
colors where min(i) = 0, max(i) = 0..700mV
i.e Y(i) = max(i)/2, X(i) = max(i),
or graphically the y = x/2 line;
and
3) the line of all possible 100% Value colors
where max(i) = 700mV, min(i) = 0..700mV
i.e Y(i) = 700mV/2 + min(i)/2,
X(i) = 700mV - min(i),
or graphically the y = -x/2 + 700mV
Note: All valid rgb values (r(i), g(i), or b(i)
within the range 0.. 700mV) are contained
within the Spearhead triangular gamut
space. All invalid (or illegal) rgb values
(min(i) < 0, or max(i) > 700mV) are outside
the Spearhead gamut space. Adjustable
gamut limit detector thresholds are indicated
as graticule markers (i.e. -0.5% and 105%).
2/17/201018
Constant Hue Test Pattern with combinations of Saturation and Value in 25% intervals
2/17/201019
Rainbow Pattern with Color Corrector Green Gamma Adjustment Error
2/17/201020 Tektronix Video Insight Seminar Series20
Timing Measurement – Using Lightning display
� Bowing indicates a timing error
4 Direction shows advance or delay
4 Location shows which component is at fault
4 Crosshairs quantify
2/17/201021 Tektronix Video Insight Seminar Series21
Construction of Lightning display
2/17/20102222
Color Error Shown Crosshatched
YellowError
2/17/201023 Tektronix Video Insight Seminar Series23
Good Y Pb Pr & RGB but Bad NTSC
2/17/201024 Tektronix Video Insight Seminar Series24
Color Error Shown Crosshatched
YellowError
2/17/201025 Tektronix Video Insight Seminar Series25
Color Error Corrected
2/17/201026 Tektronix Video Insight Seminar Series26
Checking Format Conversion
HD
Content
SD
Content
2/17/20102727
Video Session
� Shows SDI input
� Signal format
� SMPTE 352 Payload ID (more on this later)
� SAV Placement Errors
� Field Length Errors
� Line Length Errors
� Line Number Errors
� Stuck Bits
� CRC Checksum Errors
– Error Sec, # of Error Fields
% Error Fields
2/17/201028 Tektronix Video Insight Seminar Series28
CRC Process, (EDH)
Standard Definition 270Mb/s
High Definition1.485 Gb/s even rates(1.485/1.001) = 1.4835 Gb/s odd rates
2/17/201029 Tektronix Video Insight Seminar Series29
UnitInterval
0.8 Volts+ 10%
Jitter0.2 UI p-pAlignment
OrTiming
20% to 80%Risetime
0.4 to 1.5 nsshall not differ by more than .5 ns
SD Serial Digital Waveform
One Clock Interval 3.7ns
+/-10%Overshoot/Undershoot
2/17/201030 Tektronix Video Insight Seminar Series30
UnitInterval
0.8 Volts+ 10%
20% to 80%Risetime
< 270psshall not differ by more than 100 ps
HD Serial Digital Waveform
+/-10%Overshoot/Undershoot
Jitter0.2 UI p-pAlignment1.0 UI p-p
Timing
One Clock Interval 673ps
2/17/201031 Tektronix Video Insight Seminar Series31
HD Eye Measurement
80%
20%
AmplitudeAmplitude
Rise Time
Rise Time
Fall Time
Fall Time
Auto MeasureAuto Measure
2/17/201032 Tektronix Video Insight Seminar Series32
Eye Specifications Summary
Rise/Fall Time
SD HD 3Gb/s
Shall be no less than 0.4ns, no
greater than 1.50ns,
and shall not differ
by more than 0.5ns
Shall be no greater than 270ps and
shall not differ by more than 100ps
Shall be no greater than 135ps and
shall not differ by more than 50ps
Unit Interval
SD (259M)
HD (292M)
3Gb/s (424M)
3.7ns 673.4ps 336.7ps
UnitInterval
0.8 Volts+ 10%
Jitter 20% to 80%Risetime
+/-10%Overshoot/Undershoot
2/17/201033 Tektronix Video Insight Seminar Series33
The variation in position of a signal’s
transitions relative to those of a clock
extracted from the signal.
The variation in position of a signal’s
transitions occurring at a rate greater than
a specified frequency, typically 10Hz
Alignment Jitter
SD HD 3Gb/s
0.2UI (740ps) @ 1kHz
0.2UI (135ps) @
100kHz
0.3UI (101ps) @
100kHz MaximumPreferred 0.2UI
(67.3ps) @ 100kHz
Timing Jitter (10Hz)
SD HD 3Gb/s
0.2UI (740ps) 1.0UI
(673.4ps @ 1.485Gb/s)
(674ps @ 1.4835Gb/s)
2.0UI
(673.4ps @ 2.97Gb/s)
(674ps @ 2.967Gb/s)
Jitter Measurements� Timing Jitter
� Alignment Jitter
33
2/17/201034 Tektronix Video Insight Seminar Series34
Eye and Jitter Measurements at a Glance
� Physical Layer Measurements at a Glance
� Multiple Eye Displays
– 3 Eye, 10/20 Eye
� Two Jitter Measurement
– Timing Jitter
– Alignment Jitter
� Automated Eye Measurements
– Amplitude
– Rise/Fall Time
– Cable Length Measurements
– Two Jitter Readouts
2/17/201035 Tektronix Video Insight Seminar Series35
Transmission Path VerificationEye test procedure
1. Initial cable length – test signal
2. Increase cable length (87 m)
� Amplitude decrease
� Reduced Frequency Response
� Increased Rise & Fall Times
� Eye Opening barely discernible
� Jitter does not change
3. Increase cable length (> 120 m)
� Non Discernible Eye
� No Errors Indicated
� Equalizer still able to recover
4. See equalized eye
� A receiving device could still recover
the data
2/17/20103636
HD Eye Measurement
80%
20%
AmplitudeAmplitude
Rise Time
Rise Time
Fall Time
Fall Time
Auto MeasureAuto Measure
2/17/20103737
Jitter Display and Measurement
� Demodulation method
� Shows jitter related to video
line and field rates
� Launch amplitude of device
should be less than 0.2UI
2/17/201038 Tektronix Video Insight Seminar Series3838
SMPTE424M Signal/Data Serial Interface
� Defines the transport of bit-serial data structure for 3.0Gb/s
� Using a single coaxial cable interface
� Supports either 10 or 12 bits data words
� Mapped into two virtual interfaces
– 10 bit parallel data streams (Data Stream One & Data Stream Two)
Data stream one of the virtual interface
Interface Frequency 148.5MHz or
148.5/1.001 MHz
Data stream two of the virtual interface
Interface Frequency 148.5MHz or
148.5/1.001 MHz
SA
V
EA
V
+ L
ine
No
. +
CR
C
Digital Active Line
Active Picture or Ancillary Data
SA
V
Digital Line Blanking
Blanking Level or Ancillary Data
SA
V
EA
V
+ L
ine
No
. +
CR
C
Digital Active Line
Active Picture or Ancillary Data
SA
V
Digital Line Blanking
Blanking Level or Ancillary Data
Digital Line Period
2/17/201039 Tektronix Video Insight Seminar Series39
Tektronix patented Timing display
2/17/201040 Tektronix Video Insight Seminar Series40
Tektronix patented Timing display
2/17/201041 Tektronix Video Insight Seminar Series41
Timing Measurement – Using Lightning display
� Bowing indicates a timing error
4 Direction shows advance or delay
4 Location shows which component is at fault
4 Crosshairs quantify
2/17/20104242
Pathological Signals - Stress TestingSDI Checkfield
20 BITS
19 BITS
1 BIT
20 BITS
HORIZONTAL ACTIVE LINE ONLY
� Condition occurs once per field for a complete line
VERTICAL BLANKING INTERVAL
FIRST HALF OF ACTIVE FIELD
300h, 198h
FOR CABLE EQUALIZER TESTING
SECOND HALF OF ACTIVE FIELD
200h, 110h
FOR PHASE LOCKED LOOP TESTING
2/17/20104343
Digital Closed Captions
� HD 708 Captions are a data stream in the VANC of the SDI video
2/17/20104444
Ancillary header flag with examples
000
ADF
3FF,3FF
ADF 2E7
DID
21B
SDID
/DBN
218
DC
2/17/20104545
Simultaneous Closed Caption Display
2/17/20104646
� AFD describes the aspect ratio of video signals
� AFD codes embedded in video signals using SMPTE 2016-3
� Allow video processing equipment to correctly format the picture
� Used by display devices and set-top boxes to automatically control how pictures are formatted
� Various methods have been used in Europe for these type of aspect ratio formatting
– Wide-Screen Signaling (WSS)
– Video Index
Active Format Description
46
2/17/201047 Tektronix Video Insight Seminar Series47
� SMPTE 2016 – 1 Format for Active Format Description and Bar Data
� SMPTE 2016 – 2 Format for Pan-Scan Information
� SMPTE 2016 – 3 Vertical Ancillary Data Mapping of Active Format Description and Bar Data
� SMPTE 2016 – 4 Vertical Ancillary Data Mapping of Pan-ScanInformation
� ATSC A/53 – AFD Carriage in MPEG2
� CEA-CEB16 – Digital Receiver Guidelines
Standards Documents
47
2/17/20104848
Waveform Monitor Picture View with AFD
2/17/20104949
Multi-Channel Audio MonitoringSurround Sound Display
� Allows visualization of interaction between multiple channels
– Left (L), Right (R), Center (C), Left Surround (Ls), Right Surround (Rs)
– Show Dominant Sound
– Correlation between channels
– Phantom Phase Indicators
– Linear or A Weighting Filters
2/17/20105050
Phantom Source Indicators
� Associated with each channel pair
� Provides indication on the localization of the sound
� White tic mark indicates correlated sound (+1)
� Slightly Correlated (<0.9)
� Negative Correlation (<0.2)
� Out of Phase (-0.3)
2/17/20105151
Configuring Loudness Measurement
� Select Weighting Filter
� Select Duration
� Select Start & Stop Time
� Leq or LAeqmeasurements
– Individual Channel
– Channel Pairs
– Selected Channels
– 10 second Short Average
– Program Average
True PeakAudio Level
2/17/20105252
ITU-R Template
C'C
Detectability Threshold
Unacceptability Threshold
Sound Advanced wrt
Vision
Sound Delayed wrt
Vision
Undetectability Plateau
B B'
A A'
-2
-1.5
-1
-0.5
0
-200 -180 -160 -140 -120 -100 -80 -60 -40 -20 0 20 40 60 80 100
Delay time (ms)
Su
bje
cti
ve
Eva
lua
tio
n R
es
ult
s (
Dif
fgra
de
)
2/17/201053 Tektronix Video Insight Seminar Series53
AV Delay Measurement Audio Advanced
� Measurement made on a AMM768
� Or on a WFM7120
� Or on a WVR7120