AFD - PBS

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QG

Implementing AFD at PBS member station WSIU

Terry Harvey WSIU/ Southern Illinois University, Carbondale Illinois

NETA QG Workshop January 13, 2011

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AFD – What is it?

AFD is Active Format Description: defines aspect ratio.

AFD is used to define how the video originating in one aspect ratio may be “optimally” displayed on a display of a different aspect ratio.

AFD metadata is carried in baseband video and in an MPEG2 transport stream.

QG NETA QG Workshop January 13, 2011

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AFD broadcast from WSIU

 All HD programs and interstitials have AFD added.

 AFD no benefit to consumer DTV receivers:  Older DTV receivers do not use AFD  Newer DTV receivers are 16:9 and HD AFD not required!

 Cable and DTH Satellite benefit from AFD: head end IRD correctly formats for 4:3.

QG NETA QG Workshop January 13, 2011

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Complete list of AFD codes Values from ETSI TS 101 154 V1.7.1 Annex B, ATSC A/53 Part 4 and SMPTE 2016-1-2007

0 1 2 3 4 5 – 7 8 9

ESTI: reserved; ATSC: undefined reserved ETSI: 16:9 active picture (top aligned); ATSC: "not recommended" ETSI: 14:9 active picture (top aligned); ATSC: "not recommended" ETSI: box > 16:9 (center): wider than 16:9 active picture. The aspect ratio of the source area is not given, and the size of the top/bottom bars is not indicated.

ATSC: bar data (indicating the extent of top, bottom, left, and right bars) should be transmitted when using this code.

reserved Full Frame image, same as the frame (4:3 or 16:9).

4:3 Image: Full Frame in 4:3 frame, Pillarbox in 16:9 frame.

10 11 12 13 14 16:9 Image: Letterbox in 4:3 frame, Full Frame in 16:9 frame.

14:9 Pillarbox/Letterbox image.

unused 4:3 with shoot and protect 14:9 centre. The term "shoot and protect" is not explained in the standard, but means that the areas above and below the central 14:9 region of the 4:3 active picture can be trimmed without losing important detail.

16:9 with shoot and protect 14:9 centre. Here, the areas to the right and left of the central 14:9 region of the 16:9 active picture can be trimmed without losing important detail.

15 QG

16:9 with shoot and protect 4:3 centre. Here, the areas to the right and left of the central 4:3 region of the 16:9 active picture can be trimmed without losing important detail.

NETA QG Workshop January 13, 2011

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List of AFD codes that benefits us Values from ETSI TS 101 154 V1.7.1 Annex B, ATSC A/53 Part 4 and SMPTE 2016-1-2007 8 - Full Frame image, same as the frame (4:3 or 16:9).

9 - 4:3 Image: Full Frame in 4:3 frame, Pillarbox in 16:9 frame.

10 -16:9 Image: Letterbox in 4:3 frame, Full Frame in 16:9 frame. 15 -16:9 with shoot and protect 4:3 centre. Here, the areas to the right and left of the central 4:3 region of the 16:9 active picture can be trimmed without losing important detail.

QG NETA QG Workshop January 13, 2011

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List of AFD codes that we need only use.

Values from ETSI TS 101 154 V1.7.1 Annex B, ATSC A/53 Part 4 and SMPTE 2016-1-2007

8 (1000)

Full Frame image, same as the frame (4:3 or 16:9).

9 (1001)

4:3 Image: Full Frame in 4:3 frame, Pillarbox in 16:9 frame.

QG NETA QG Workshop January 13, 2011

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Without Broadcast AFD

HD Broadcast Cable TV Forced Letterbox AFD absent Forced Center Cut AFD absent

NETA QG Workshop January 13, 2011

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With Broadcast AFD

HD Broadcast Cable TV AFD Controlled Center Cut AFD 1001 AFD Controlled Letterbox AFD 1000

NETA QG Workshop January 13, 2011

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How is the AFD conveyed?

 AFD will be carried in HD and SD baseband Serial Digital Video Interface in the VANC as per SMPTE-334M. (HD-SDI VANC line 11).

QG NETA QG Workshop January 13, 2011

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How is the AFD conveyed?

 In ATSC over-the-air transmission, the AFD is carried in the picture user data bits in MPEG2 Transport Stream.

Transport Stream Packet Transport Stream Packet Transport Stream Packet Transport Stream Packet Transport Stream Packet Header Video Payload Adaptation Field

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Picture User Data Bits

NETA QG Workshop January 13, 2011

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AFD: Practical Implementation

 Must ensure a correct AFD code is applied to all program elements in HD broadcast: eg. HD and upconverted SD content.

 HD and SD AFD is supported but PBS does not yet forward SD-AFD.

 Member station must therefore generate AFD for SD and all local content.

QG NETA QG Workshop January 13, 2011

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Prerequisites for AFD- IRDs

 IRDs (Satellite Receivers): Older IRDs (BitLinks) do not employ AFD decoding (eg extraction of AFD from transport stream and placement in HD-SDI VANC).

 Sencore MRD3187 IRDs do employ AFD (Note earlier MRD3187B’s need upgrading).

 ASI interface on Bitlink will convey AFD.

QG NETA QG Workshop January 13, 2011

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Prerequisites for AFD - Servers

 Most servers now record and playback HD and SD AFD.

 AFD extracted from baseband input VANC stored with caption data in auxiliary referenced file.

 AFD extracted from transport stream when recorded via ASI must be stored and made available for baseband VANC playback.

QG NETA QG Workshop January 13, 2011

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Prerequisites for AFD - Encoders

 AFD carried in HD-SDI VANC must pass through the master control switcher and applied to the MPEG2 Emission Encoder.

 Encoder must be capable of extracting AFD from HD-SDI VANC and placing AFD in MPEG2 transport picture user data bits.

QG NETA QG Workshop January 13, 2011

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Example AFD Implementation

IRD - HD IRD - SD HD Source SD Source AFD on HD-SDI Upconverter Includes AFD AFD on HD-SDI Automation GPI Control of Preset AFD codes and aspect ratio Universal Converter Includes AFD Video Server HD-SDI Master Control Switcher HD Emission Encoder

QG NETA QG Workshop January 13, 2011

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Another Example

IRD - HD No AFD on HD-SDI Video Server HD-SDI Master Control Switcher Automation GPI Control of Preset AFD codes and aspect ratio AFD Insertion Card HD-SDI with AFD HD Source SD Source Universal Converter Includes AFD HD Emission Encoder

QG NETA QG Workshop January 13, 2011

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To Ensure the Highest Quality

 Minimize unnecessary codec cycles.

 Minimize unnecessary video rescaling eg. 480i to 1080i then to 720p for emission.

 Record Full Frame 16:9 and 4:3, no local pillarbox or letterbox.

 All locally produced programming in HD and SD is now 16:9 format.

 SD to HD Upconvertor controlled by automation to correct format and add AFD.

QG NETA QG Workshop January 13, 2011

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WSIU - HD AFD

 Satellite receiver provides HD AFD from PBS.

 Server records and playbacks HD AFD.

 File based HD local production has HD AFD added at Transcode/ Transwrap when transferred to Omneon server.

 Three HD AFD format codes:    16:9 FF AFD codes 1000 16:9 FF center cut safe AFD code 1111 (from PBS) 16:9, 4:3 Pillarbox AFD code 1001

QG NETA QG Workshop January 13, 2011

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WSIU - SD AFD

 All SD recorded and archived as native SD.

 Local SD file base production has no AFD.

 SD playback upconvert to air where AFD is added.

 SD four formats:  16:9 Full Frame AFD code 1000  16:9, 4:3 Pillarbox AFD code 1001  4:3, Full Frame AFD code 1001  4:3, 16:9 Letterbox AFD code 1000

QG NETA QG Workshop January 13, 2011

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WSIU 720p Master Control with AFD

FCP files from Post Production AMC21 IRDs Ku22

HD01 HD02

Sencore IRD Ku23a

HD04

Sencore IRD Ku23b

SD05

Sencore IRD Ku23c

SD06

Sencore IRD Ku23d

SD07

Sencore IRD Ku24

HD03 SD01

Sencore IRD Transcode

Adds AFD To HD

Omneon MIP-4010 Omneon MIP-4010 Omneon MIP-4010 Omneon MIP-4010 Omneon MIP-4010 Omneon MIP-4010

ASI Record Ports for SD and HD

Omneon Spectrum Video Server Omneon MIP-5321 VDCP Omneon MIP-5321 1080i VDCP Omneon MIP-5321 VDCP 720p 480i Evertz 7812 CC 720p Evertz 7812 UDX 720p GPI for Aspect Ratio and AFD NVerzion Automation ProTrack

QG NETA QG Workshop January 13, 2011

720p 20

QG NETA QG Workshop January 13, 2011 ProTrack Database Record for SD 16:9

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QG NETA QG Workshop January 13, 2011 ProTrack Database Record for SD 16:9

ProTrack facilitates identification of aspect ratio.

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QG NETA QG Workshop January 13, 2011 ProTrack Database Record for SD 16:9

ProTrack also differentiates between video formats 1080i , 720p and 480i: Each can be 16:9.

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WSIU Playlist

SVR1A SVR1B – HD Playback – SD Playback Formats for SVR1B (SD) NS = 4:3 Full Frame LB = 4:3,16:9 Letterbox WS=16:9 Full Frame PB =16:9,4:3 Pillarbox AFD for SVR1A (HD) -from HD File AFD for SVR1B (SD) NS = 9 (1001) LB = 8 (1000) WS = 8 (1000) PB = 9 (1001)

QG NETA QG Workshop January 13, 2011

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AFD – It Does Work!

 PBS began applying AFD to HD programs April 2009.

 WSIU began broadcasting AFD in July 2009.

 All WSIU programming and individual WSIU interstitials have AFD applied.

 Broadcast SD Distributors using WSIU AFD:  DirecTV and Dish Network July 2009  Charter Communications September 2009  MediaCom July 2010

QG NETA QG Workshop January 13, 2011

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