Grass Valley K2 Series Media Server Application Note

K2 AFD Concepts and Operation
How the K2 Media Server Solves SD-to-HD Transition Problems with Regards
to Aspect Ratio Conversion (ARC) and Active Format Description (AFD)
Roger Crooks, Product Marketing Manager Grass Valley, a Belden Brand— October 2009
APPLICATION NOTE K2 AFD CONCEPTS AND OPERATION
TABLE 3.
the Problem
OF Defining
3.Active Format Description (AFD) & Bar
CONTENTS
Data
3.Aspect Ratio Conversion (ARC)
3.Wide Screen Signaling (WSS) & Video
Index
4.
Metadata Throughout
the Workflow
4.Ingest – SDI Signals
4.Ingest – File Transfers
5.Edit
5.Playout
5.AFD Settings on SDI
Output
6.AFD Settings on File
Output
7.
8.
Supported
Conversions Using
AFD
9.
Default AFD Settings
10.
Specifications
10.Additional Specifications
10.Summary
10.Definitions
10.SMPTE Standards
11.
Appendix A: Active
Format Description
12.
Appendix B: Aspect
Ratio Conversions on
HD K2 Server Models
Examples
7.Example 1 – SD/HD
Newscast
7.Example 2 – Impact
of an incorrect AFD
setting
7.Example 3 – File
Transfers
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APPLICATION NOTE K2 AFD CONCEPTS AND OPERATION
W
hen dealing with both SD and HD content for an SD or HD broadcast channel, there are many technical issues to deal with that were
not an issue with SD-only playout. This tech note focuses on how the K2 media server automatically deals with these issues by setting
and preserving the correct clip metadata. This includes AFD, which defines the aspect ratio of the signal as it progresses through the
workflow; ingest, editing, up/down conversion and playout. The goal of recent SMPTE standards is to preserve the correct description of the
signal throughout the process so the consumer sees the picture as the broadcaster meant it to be seen.
Defining the Problem
Problems may arise when broadcasting SD
& HD content because:
Active Format Description (AFD)
& Bar Data
Wide Screen Signaling (WSS) &
Video Index
1. SD Content can be in 4:3 or 16:9
The Active Format Description is a 4-bit code
(a0, a1, a2, a3) describing the video picture
in terms of the aspect ratio and other characteristics of the active image within the coded
frame. The complete set of Active Format
Description codes is shown in Appendix A.
Outside the US, WSS was sometimes used
with SD signals to define the aspect ratio as
16:9 or 4:3. It did not include as much information about the image inside the raster as
AFD. WSS is stored on VBI line 20 (NTSC) or
line 23 (PAL) luma.
Additionally, AFD includes an aspect ratio (AR) bit stored as “b2” which indicates
whether the picture is 16:9 (1) or 4:3 (0). The
K2 media server records and sets this bit
correctly.
Video Index (stored on VBI line 14 chroma)
was defined to add additional information
about the display. Together with WSS, it was
sometimes used to try to accomplish what
AFD does today.
Bar Data is 5 bytes of associated data that
defines the precise unused areas of active
video when the active image does not fill the
complete picture area, or where the bars are
asymmetrical (such as when the picture is
not centered). These cases are rarely used in
mainstream broadcast and as such, are not
supported in the K2 system.
WSS and Video Index are not used for HD
material and are replaced with AFD for both
SD and HD material.
2. HD content is always 16:9
3. A broadcaster must play out an SD or HD
channel with all three types of material and
must switch seamlessly between them all
4. The aspect ratio of the clip can be changed
at various points in the broadcast chain
5. Both set-top boxes and TV sets can crop
or scale the picture to various aspect ratios
For the set-top box or the TV to display the
most optimal picture, it must have accurate
information on the format of the picture it receives. If this information is incorrect, the resulting display will be sub-optimal using less
of the screen than desired, often described
as a “postage stamp” display. (See Figure 1).
Aspect Ratio Conversion (ARC)
The K2 media server has many different aspect ratio conversion options as shown in
Appendix B. It’s critical that the AFD accurately represents the image of the signal as it
leaves the server, with or without conversion.
If the signal has AFD and it is converted, the
AFD code needs to reflect the change.
The K2 media server will pass the WSS
and Video Index signals through if the user
selects these lines to be stored as uncompressed. If the clip is up-converted, WSS
and Video Index are not preserved as they
are not defined for HD. As described in this
tech note, the K2 media server will correctly set AFD regardless of the WSS and Video
Index settings.
Potential Conversion Problems at the Set-top
16:9 Production (AFD=1010)
Broadcast 4:3
Letterbox (AFD=1010)
Viewer 16:9 Display
Postage Stamp
Display if no AFD
4:3 Production (AFD=1000)
Figure 1 – Examples of displays
resulting from no or incorrect
AFD information. Consumers
complain when only a portion of
their video screen is used.
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Broadcast 16:9
Pillarbox (AFD=1001)
Viewer 4:3 Display
Postage Stamp
Display if no AFD
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APPLICATION NOTE K2 AFD CONCEPTS AND OPERATION
Metadata Throughout the Workflow
Preservation of a clip’s metadata is crucial in
a file-based workflow. The K2 media server
not only preserves metadata throughout the
workflow, but also makes it easily available
to other application via the protocols. For
content on a K2 media server, metadata can
be stored in two locations: K2 Movie Properties and K2 Ancillary Data Track.
K2 Movie Properties – Clip metadata is
stored in the K2 Movie Properties, which is
a database for details of the clip such as
length, compression format, marks, etc. It is
easiest for applications to access this metadata. K2 media server stores AFD in Movie
Properties and uses this data throughout the
workflow. Users can check/modify the AFD
setting via AppCenter.
AFD
AFD
AFD
AFD
AFD
AFD
• The MXF/GXF ANC data track is copied to
K2 ANC data track unchanged
SDI Video/Audio
AFD
AFD
AFD
AFD
AFD
AFD
AFD
AFD
AFD
AFD
AFD
File Ingest
The AFD setting in the MXF/GXF metadata field is copied into the K2 Movie Properties.
The ANC data track is copied into the K2 ANC data track
AFD
AFD
AFD
AFD
AFD
AFD
AFD
SDI Output
For SDI output, the AFD representing the ARC performed is inserted
into the SDI ANC Data Track.
MXF/GXF
Metadata
SDI Video/Audio
AFD
• ARC Property in GXF from pre V3.3 K2
systems is preserved to maintain backward compatibility
New AFD
AFD
K2 ANC data track
AFD
• If neither, no AFD is set
Aspect Ratio
Conversion
K2 Movie
Properties
AFD
MXF/GXF
Metadata
• If no AFD metadata, AFD from two seconds in on the ANC data track is copied to
the K2 Movie Properties
Process
The AFD setting will determine the ARC
performed on an up or down
conversion. A new AFD setting is set.
AFD
AFD
• AFD from MXF/GXF metadata is copied to
K2 Movie Properties
An SDI video signal stores AFD in the ANC
data track (VANC). If AFD is present, its setting two seconds into the file is copied into
the K2 Movie Properties (See Figure 2). The
ANC data track is copied into the K2 ANC
Data track (if selected).
SDI
AFD
For a MXF/GXF file transfer, the AFD is set in
this priority order:
Ingest – SDI Signals
Edit
The user can set/correct the
AFD in Movie Properties
SDI Ingest
If an SDI signal has AFD
set in the ANC data track
then it is copied into K2
Movie Properties and the
ANC data track is copied
into K2 Ancillary data
track
Ingest – File Transfers
K2 Ancillary Data Track – A clip being recorded on a K2 media server has the option
of storing an Ancillary Data Track (playout
always has an Ancillary Data Track). This is
a user option and seldom used for SD clips,
but it should always be selected for HD clips.
Specifying a K2 Ancillary Data Track will take
more storage (approximately equal to four
tracks of audio) but will enable AFD and CC/
Teletext support for HD.
AFD
SDI Video/Audio
AFD
AFD
AFD
AFD
AFD
AFD
AFD
AFD
AFD
File Output
For MXF/GXF file transfers, the Movie Property AFD setting is copied into the MXF
Metadata field and the original ANC Data track is copied into the stream And Data track.
Figure 2 – Example of how AFD is handled when the incoming material contains AFD.
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APPLICATION NOTE K2 AFD CONCEPTS AND OPERATION
Metadata Throughout the Workflow (Cont.)
Edit
The user can view, add or change AFD information manually through
AppCenter or remotely via the K2’s protocols – K2.net or AMP. If the
user sets or changes AFD, it is changed in the Movie Properties — the
original AFD in the Ancillary Data Track remains as it was.
When starting a record, the user can set the format of the input video.
This setting is used as the AFD property of the clip being recorded if it
does not contain AFD. If the clip contains AFD, the clip’s AFD setting
will override this user setting.
SD
HD
Undefined
Undefined
Full screen 4:3
Full screen 16:9
Letterbox 16:9
Pillarbox 4:3
Letterbox 14:9
Pillarbox 14:9
Full screen 16:9
Full screen 16:9 with alternate 4:3 center
Figure 3 – AFD setting available when recording video.
Playout
The K2 media server has the built-in ability
to process the video on playout, which in a
hybrid SD and HD environment can save tremendous cost and time by eliminating specialized equipment downstream.
Up and Down Conversion – A K2 channel
can be configured for SD or HD playout. Both
SD and HD material can be put on a playout
channel’s timeline. If the playout channel is
configured for HD, then all SD material will
be up-converted to HD and visa versa for
an SD channel. The K2’s up/down conversion capability is a standard feature and its
quality is comparable to external conversion
equipment.
Cross Conversion – The K2 media server’s
HD output can be set up for either 720p or
1080i. If an HD channel is set for 1080i, then
720p material will be converted to 1080i and
visa versa. The K2 media server performs
this conversion in real time at playout.
Aspect Ratio Conversion – The K2 media
server has the ability to set any channel to
a default ARC, as well as on a clip-by-clip
basis. With support for AFD, users will now
set the clip’s ARC by setting the AFD code
as defined in Figure 5. This is an operational change from previous version of K2 software. This ARC setting was used to override
the channel’s default ARC setting. Now AFD
will be used to indicate the aspect ratio of
the clip and the ARC performed is determined by the K2 media server. To preserve
backward compatibility, if no AFD is set, the
ARC setting will operate as before.
K2 Movie ARC settings (see Appendix B):
• Default — use the channel default ARC
setting
AFD Settings on SDI Output
The AFD code set on output is determined
by a variety of conditions and user settings
as shown in figure 4. To cover various situations, the user can control how AFD is handled.
The user has three options for AFD control:
• Always Generate: AFD is always generated on the output regardless if the original
source contains AFD or not
• When Known Generate: AFD is only generated if the original source contains AFD
or AFD is set by the user
• Never Generate: AFD is not generated
but will play unchanged from the ancillary
data track if present.
• Stretch
• Half Bars
• Crop
• Bars
The playout priority for aspect ratio conversion is as follows:
1. AFD as stored or set by the user in the
Movie Properties
2. K2 media server’s default ARC channel
setting
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APPLICATION NOTE K2 AFD CONCEPTS AND OPERATION
Metadata Throughout the Workflow (Cont.)
Input and Settings
Output AFD Value
AFD Clip AFD Data
ARC
Generate AFD Setting
Properties
Track
Performed
As set
in Movie
Property
Y
n/a
N
Always or When Known
Y
n/a
Y
Always or When Known
N
Y
N
Always or When Known
N
Y
Y
Always or When Known
N
N
n/a
When Known
N
N
n/a
Always
n/a
Y
n/a
Never
n/a
N
n/a
Never
Derived
As set in
from Movie Data Track
Property
Derived
from Data
Track
No AFD
Default
AFD
X
X
X
X
X
X
X
X
Y = AFD value is set
N = No AFD value is set
n/a = setting does not impact output
Figure 4 – AFD output settings based on inputs and user settings.
AFD Settings on File Output
The AFD code is set in the MXF/GXF output file’s metadata and in the Ancillary data track.
• The file metadata setting is determined by the setting in the K2 Movie Properties from the original source or as set by the user
• The file ancillary data is never changed by the K2 media server – it is always the same as the ancillary data track from the original file or
source
• Note: it is possible for the Metadata AFD setting to be different from the AFD in the ancillary data track
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APPLICATION NOTE K2 AFD CONCEPTS AND OPERATION
Examples
Example 1 – SD/HD Newscast
A station simulcasts an HD and SD news
channel with exactly the same content. They
have archival SD material in standard 4:3
(AFD=1000), 16:9 widescreen (AFD=1010)
and 16:9 letterbox (AFD=1010) formats.
All the HD video is 16:9 (AFD=1010), shot in
4:3 protect mode. Archival SD video is used
during broadcast and needs to seamlessly
switch between HD and SD content.
K2 channel 1 is set to playout SD, 4:3 mode
with AFD set to down convert 16:9 HD material to letterbox (AFD=1010).
K2 channel 2 is set to playout HD, 1080i,
16:9 with AFD set to up convert 4:3 content
to pillarbox (AFD=1001).
Channel 1: SD — 4:3 — Letterbox set as
default
Example 2 – Impact of an incorrect AFD setting
• 4:3 SD Standard: Plays straight through —
AFD in the output stream is set to 1001,
AR=4:3
If the AFD setting is missing or set incorrectly, the user may see a “Postage Stamp” display where the display image is shrunk with
black bars on the top, bottom and sides.
• 16:9 SD Widescreen: Displays as letterbox — AFD in the output stream is set to
1010, AR=4:3
• 16:9 SD Letterbox: Displays as letterbox
— AFD in the output stream is set to 1010,
AR=4:3
• 16:9 HD: Down converted to letterbox —
AFD in the output stream is set to 1010,
AR = 4:3
Channel 2: HD — 16:9, Pillarbox set as default ARC
• 4:3 SD Standard: Up converted to pillarbox — AFD in the output stream is set to
1001, AR = 16:9
• 16:9 SD Widescreen: Up converted and displays full screen — AFD
in the output stream is set to 1010,
AR = 16:9
• 16:9 SD Letterbox: Up converted and displays full screen — AFD
in the output stream is set to 1010,
AR = 16:9
For example, in Figure 1, in the top example, an HD clip is down converted to SD with
a letterbox (AFD=1010). The display device
with no AFD information may shrink the letterbox display and add bars to the side giving the “Postage Stamp” effect.
The same results in the bottom example with
SD up converted clips.
Example 3 – File Transfers
AFD is also critical when transferring files
from one system to another. If AFD exists
(either originally or set by the user on the K2
media server) it needs to be preserved when
that file is sent to another K2 server, archive
or another system. The K2 media server
will pass AFD in the MXF or GXF stream as
stored or, if no AFD code is set, the K2 media server will set the AFD default code as
described in Figure 5.
• 16:9 HD: Plays straight through — AFD
in the output stream is set to 1010,
AR = 16:9
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APPLICATION NOTE K2 AFD CONCEPTS AND OPERATION
Supported Conversions Using AFD
SD to HD
SD
AFD=1010
AR=4:3
HD
SD
Scale down
letterbox
AFD=1010
AR=16:9
AFD=1000 or 1010
AR=16:9
HD
HD
Scale up
pillarbox
Scale up
AFD=1000 or 1010
AR=16:9
SD
AFD=1011
AR=4:3
HD
Scale up
crop vert.
SD
AFD=1000 or 1001
AR=4:3
HD to SD
AFD=1001
AR=16:9
HD
HD
AFD=1000 or 1010
AR=16:9
AFD=1000 or 1010
AR=16:9
HD
HD
Scale down
AFD=1011
AR=16:9
SD
SD
AFD=1011
AR=16:9
AFD=1011
AR=4:3
SD
HD
Scale down
crop horz.
AFD=1111
AR=16:9
AFD=1001
AR=4:3
AFD=1000 or 1010
AR=16:9
Scale down
crop horz.
letterbox
Scale down
crop vert.
pillarbox
AFD=1010
AR=4:3
SD
Scale down
crop horz.
AFD=1001
AR=16:9
SD
AFD=1001
AR=4:3
Figure 5 – Supported ARC Conversion using AFD for K2 HD systems.
Note: In several cases above, there are two valid AFD codes indicated. The SMPTE standard (Appendix A) describes this in notes 4 and 5. Based on customer feedback, K2 uses the second
value.
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APPLICATION NOTE K2 AFD CONCEPTS AND OPERATION
Default AFD Settings
HD
SD
Presumed
Source
Format
Presumed Source Format
SD
HD
HD
No
conversion
Not widescreen
SD
AFD = 1000
AR = 16:9
Widescreen
"Crop"
SD
Scale Up
Crop
Vertical
HD
No
conversion
No
conversion
(only if
ARC is set
to "stretch")
HD
Scale Down
Letterbox
AFD = 1010
AR = 16:9
SD
AFD = 1001
AR = 4:3
SD
AFD = 1000
AR = 16:9
"Bars"
SD
AFD = 1010
AR = 4:3
"Bars"
"Crop"
SD
HD
SD
HD
Scale Up
Pillarbox
Scale Down
Crop Horz.
AFD = 1001
AR = 16:9
AFD = 1001
AR = 4:3
N/A
"Stretch"
SD
Scale Up
HD
HD
Scale Down
HD
AFD = 1010
AR = 16:9
AFD = 1010
AR = 16:9
"Half Bars"
"Half Bars"
SD
HD
Scale Up
Crop
Vertical
Pillarbox
SD
HD
Scale Down
Crop Horz.
Letterbox
AFD = 1011
AR = 16:9
AFD = 1011
AR = 4:3
Figure 6 – Default AFD settings. When up/down converting, AFD is set according to this table.
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APPLICATION NOTE K2 AFD CONCEPTS AND OPERATION
Specifications
Additional Specifications
Definitions
Pillarbox
1. A
FD can be defined on a field-by-field or
clip basis. The K2 media server supports
clip basis. After 2 seconds of recording,
the AFD at that field is used for the whole
clip (or last frame on a clip shorter than 2
seconds)
Active Image
“Pillarbox” describes a frame that the active image does not fill horizontally, requiring
bars without active image information at the
left and/or right sides of the image. Some
publications, including SMPTE RP 199, refer
2. AFD Bar Data is not supported (rarely
used)
3. AFD Aspect Ratio bit is supported (4:3 or
16:9)
4. S
upported K2 Media Clients: K2-SD-04,
K2-HD-xx, K2 Summit. K2-SDA-22 does
not support AFD
Summary
A video server that supports the current
SMPTE standards will result in a better looking picture without the extra cost and complexity of downstream equipment. The K2
media server fills this requirement for quality
SD and HD broadcasts.
The Active Image is the portion of the video
picture area that is being utilized for program
content. In CEA-CEB16 it is defined as the
useful image inside the video frame. Active
Image excludes letterbox bars and pillarbox
bars.
Letterbox
PillarBox
Coded Frame
The Coded Frame is the video frame as coded in a compressed bitstream for emission.
For consistency with ATSC, CEA, ETSI and
other standards, the Active Format Description and Bar Data specifications in this document refer to the term Coded Frame. For
the purpose of this SMPTE standard, use of
the words “Coded Frame” shall be taken to
apply also to the active video area defined by
the applicable production format standard
for the video signal being described by the
AFD and Bar Data.
Letterbox
“Letterbox” describes a frame that the active
image does not fill vertically, requiring bars
without active image information at the top
and/or the bottom of the image.
Active Image
4:3 PillarBox
Coded Frame
16:9
Figure 7 – Active Image vs. Coded Frame
Figure 8 – Two most popular cropping formats
to pillarbox in a 16:9 display area by the term
“sidebar.”
Anamorphic Widescreen
This is a term used to describe a videographic technique utilizing rectangular (wide) pixels to store a widescreen image to standard
4:3 aspect ratio.
SMPTE Standards
SMPTE
2016-1
Format for Active Format Description and
Bar Data
SMPTE
Format for Pan-Scan Information
2016-2
SMPTE
2016-3
Vertical Ancillary Data Mapping of Active
Format Description and Bar Data
SMPTE
2016-4
Vertical Ancillary Data Mapping of Pan-Scan
Information
SMPTE
2016-5
KLV Data Coding for Active Format Description, Bar Data and Pan-Scan Information
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APPLICATION NOTE K2 AFD CONCEPTS AND OPERATION
Appendix A: Active Format Description
Active Format Description codes from SMPTE 2016-1 Specification
Active Format Description
In a 4:3 coded frame
AFD Code
In a 16:9 coded frame
a3, a2, a1, a0
Undefined (see below)
Undefined (see below)
‘0000’
Reserved
Reserved
‘0001’
Letterbox 16:9 image, at top of the coded frame
(see note 1)
Full frame 16:9 image, the same as the coded frame
(see notes 1 and 2)
‘0010’
Letterbox 14:9 image, at top of the coded frame
(see note 1)
Pillarbox 14:9 image, horizontally centered in the coded frame
(see notes 1 and 3)
‘0011’
Letterbox image with an aspect ratio greater than
16:9, vertically centered in the coded frame (see note
1)
Letterbox image with an aspect ratio greater than 16:9, vertically
centered in the coded frame (see note 1)
‘0100’
Reserved
Reserved
‘0101’
Reserved
Reserved
‘0110’
Reserved
Reserved
‘0111’
Full frame 4:3 image,
the same as the coded frame
Full frame 16:9 image, the same as the coded frame
‘1000’
Full frame 4:3 image,
the same as the coded frame (see note 4)
Pillarbox 4:3 image, horizontally centered in the coded frame
‘1001’
Letterbox 16:9 image, vertically centered in the
Full frame 16:9 image, with all image areas protected (see note 5)
coded frame with all image areas protected (see note
5)
Letterbox 14:9 image, vertically centered in the
coded frame
‘1010’
Pillarbox 14:9 image, horizontally centered in the coded frame
‘1011’
Reserved
Reserved
‘1100’
Full frame 4:3 image, with alternative 14:9 center
(see note 6)
Pillarbox 4:3 image, with alternative 14:9 center (see note 6)
‘1101’
Letterbox 16:9 image, with alternative 14:9 center
(see note 6)
Full frame 16:9 image, with alternative 14:9 center (see note 6)
‘1110’
Letterbox 16:9 image, with alternative 4:3 center
(see note 6)
Full frame 16:9 image, with alternative 4:3 center (see note 6)
‘1111’
Notes:
If Bar Data is not present, AFD ‘0000’ indicates that exact information is not available and the active image should be assumed to be the same
as the coded frame. AFD ‘0000,’ when accompanied by Bar Data, signals that the active image’s aspect ratio is narrower than 16:9, but is not
4:3 or 14:9. As the exact aspect ratio cannot be conveyed by AFD alone, wherever possible AFD ‘0000’ should be accompanied by Bar Data
to define the exact vertical or horizontal extent of the active image.
AFD code ‘0100’ signals that the active image aspect ratio is wider than 16:9. As the exact aspect ratio cannot be conveyed by AFD alone,
wherever possible AFD ‘0100’ should be accompanied by Bar Data to define the exact vertical extent of the active image.
Bar Data is not supported by the K2 media server as these formats are not commonly used today in broadcast.
1. In determining AFD codes to originate, readers are cautioned that emission systems in some areas of the world may not support some or
all of AFD codes ‘0001’ through ‘0111.’
2. In a 16:9 coded frame, AFD code ‘0010’ represents the same image display as AFD code ‘1000.’ AFD code ‘1000’ is the preferred coding
for full-frame 16:9 images. AFD code ‘0010’ is not used in North America.
3. In a 16:9 coded frame, AFD code ‘0011’ represents the same image display as AFD code ‘1011.’ AFD code ‘1011’ is the preferred coding
for a horizontally centered 14:9 pillarbox image. AFD code ‘0011’ is not used in North America.
4. In a 4:3 coded frame, AFD code ‘1001’ represents the same image display as AFD code ‘1000.’ AFD code ‘1000’ is the preferred coding for
full-frame 4:3 images.
5. AFD code ‘1010’ is intended for use with images that may not fill the frame vertically but where all areas of the image should be displayed
(i.e., an image where cropping is not permitted) and which therefore can only be adequately displayed in letterbox format.
6. The “alternative center” image refers to an area of essential picture information. The areas outside this area (shown gray in the illustrations)
may optionally be cropped without significant loss to the viewer.
7. Aspect ratio information for the coded frame is not part of the AFD code and it is necessary to code this aspect ratio information separately.
The AFD and aspect ratio codes may be transported together as part of a larger data structure.
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APPLICATION NOTE K2 AFD CONCEPTS AND OPERATION
Appendix B: Aspect Ratio Conversions on HD K2 Server Models
S o u r c e Source Image
Aspect
Ratio
C o n v e r s i o n Conversion Description
Option
4:3
16:9
Converted Converted Image
A s p e c t
Ratio
Bar
The 4:3 aspect ratio is maintained centered on
the screen, with black bars filling the left and right
portions of the 16:9 display.
16:9
Half Bar
The picture aspect ratio is maintained, but the
image is slightly enlarged. The top and bottom of
the image are slightly cropped, and thin black bars
fill the left and right portions of the 16:9 display.
16:9
Crop
The picture aspect ratio is maintained, but the
image is enlarged so that it horizontally fills the HD
display. The top and bottom of the 4:3 SD image
are cropped to fit in the 16:9 display.
16:9
Stretch
The picture aspect ratio is distorted. The image
fills the screen vertically without cropping, and is
stretched horizontally to fill the 16:9 display. This
conversion upconverts Full Height Anamorphic
(FHA) 16:9 SD material.
16:9
Bar
The 16:9 aspect ratio is maintained, centered
on the screen, with black bars filling the top and
bottom portions of the 4:3 display.
4:3
Half Bar
The picture aspect ratio is maintained, but the
image is slightly enlarged. The left and right sides
the image are slightly cropped, and thin black bars
fill the top and bottom portions of the 4:3 display.
4:3
Crop
The picture aspect ratio is maintained, but the
image is enlarged so that it vertically fills the SD
display. The left and right sides of the 16:9 HD
image are cropped to fit in the 4:3 SD display.
4:3
Stretch
The picture aspect ratio is distorted. The image
fills the screen horizontally without cropping, and
is stretched vertically to fill the 4:3 display. This
conversion generates Full Height Anamorphic
(FHA) 16:9 SD material.
4:3
GVB-1-0128A-EN-AN
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