Shared HD Workflows For Post And Broadcast


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Shared HD Workflows For Post And Broadcast

  1. 1. Shared HD workflows for Post and Broadcast Trevor Francis Worldwide Marketing Manager Quantel Ltd Newbury, 1
  2. 2. Quantel’s principal markets News Sports Post Digital Intermediate (Film) All require sharing of media and projectsQuantel delivers solutions to four principal market sectors: News, Sports, PostProduction and Digital Intermediate for the film industry. All four requirecollaborative workflows to deliver the speed and efficiency required by profitablebusiness.Each of the four has forward-looking requirements to meet the changingdemands of the industry. For broadcasters, some key technology drivers areHigh Definition, multi-platform delivery and the adoption of standardised ITcomponents wherever possible.For Film and Post Production, 3D stereoscopic is rapidly accelerating as the nextmust-have. The traditional Post industry is forced to re-invent itself as thecapabilities of inexpensive software bring compositing, complex effects,animation and even colour correction to even the smallest production house. 2
  3. 3. Quantel: teamworking on AvatarQuantel is proud of its association with the production of Avatar: Every frame ofthe film as well as all the trailers and promotions have passed through LA posthouse Modern Video Film’s set of three Quantel Pablo Stereo3D systems. Thework completed on Pablo includes conforming and Stereo3D checking,adjustment and quality control. Crucially, the Pablos have also handled all theStereo3D English subtitling required for the Navi language used by somecharacters in the film. 3
  4. 4. Production timescales Months…. years Film DI Weeks… months Post Minutes TV / WebThe production timescales around the branches of the industry vary enormously.Complex projects like Avatar may be months or even years in Post Production.For TV Post, lead times of many weeks or months are common. For livebroadcasting it’s far more immediate, with Sport and News requiring a job to becompleted in a handful of minutes – or less. 4
  5. 5. File sizes 2k, 4k 1080i, 1080p Compressed SD, HD H264, Quicktime etcThe file sizes, file types, compression and wrapper formats are also diverse. ForFilm, 2k and 4k are normal. TV Post is rapidly heading upwards to 1080p –doubling the data rates for 1080i. Mainstream broadcasting may bepredominantly still SD around the world, but the move to HD is acceleratingrapidly, with 1080p moving up for Sport.Much smaller files are in use both for the acquisition and distribution of contentvia the internet. With consumer HD cameras in daily use around the world, addedto the millions of camera-equipped mobile telephones, we’re all now potentialphoto-journalists, so the broadcasters must be able to accept this content intotheir production and playout systems.Most of us still watch TV on TV receivers, but the number using phones,computers and even games machines to screen content is growing fast. Theseare important outlets for the broadcasters. They have to provide files suited tothese distribution channels. 5
  6. 6. A solution for Film and high-end Post Conforming, Grading, Effects, Compositing, Deliverables • Up to 4K image sizes • Uncompressed media • Shared workflows • 3DTo begin our discussion of shared workflow solutions, let’s look at a solution forFilm and high-end Post Production. Typical workflows will include conforming,grading, effects, compositing and deliverables.These are typically using uncompressed media files of up to 4K. So sharing theseisn’t trivial. Copying and moving files of this size is enormously time-consumingand resource-hungry. 6
  7. 7. A big SAN will fix it, right? ?The idea of enabling the various applications to share a common pool of storageusing a SAN is a good one. No time is wasted when transferring betweenapplications and as a consequence there is considerable operational flexibilityabout what happens and when. However, while SANs bring many benefits, thereare many real-world issues that arise: 7
  8. 8. The non-workflow workflow diagram More Media Managers Media Managers ××Guaranteed playback? Guaranteed playback? VFX VFX VFX VFX ××lots of copies lots of copies ××inefficient use of storage inefficient use of storage On Conform line ××parent child deletion protection parent child deletion protection On ××metadata incompatibility Retouch metadata incompatibility SAN SAN line ××essence incompatibility essence incompatibility Central Retouch Store Colour ××even more copies even more copies Format ××creative changes convert creative changes Film Tape Scan Scan Format Rec Out convert Media ManagementSAN performance may not be adequate to support enough real time clients without imposingunrealistic limits such as leaving 50% of disk space free for internal mechanisms to guaranteeperformance.SAN performance under fault conditions, e.g. rebuilding failed disks may be an automatic processbut it can impact the number of real-time concurrent usersProviding multiple streams of 2K and 4K remains a challenge in some systems. All the abovemake providing a mission critical shared environment almost impossible so local storage is oftenintroduced where absolute reliability is required, i.e. client review, ingest and playout. Of coursethis adds inefficiency, increases costs and produces more copies of media to be managed.Applications may copy data to reorder it (edit it), this quickly leads to not only inefficient use ofdisk space but also adds a management overhead to manage all the copies of data.Different applications may support different file formats, resolutions, colour spaces or even bit-depths. These application-imposed limits mean media must be converted before it can be sharedmeaning new file conversion applications and more copies of data to be stored.Incompatible metadata between different applications and the inability to roundtrip dark metadatamean flexibility is lost when work moves between systems and external asset management needsto be introduced to track what happened where. This becomes a big overhead once the usualcreative changes part way through the process start to occur.These issues are well understood by manufacturers of high-end edit systems and are the reasonwhy close-coupled direct attach storage is still widely used in practice with SAN based solutions. 8
  9. 9. Teamworking in Post NAS/SAN LAN Audio Shared WorkspaceAn ideal sharing infrastructure for post and DI would suffer from none of the above drawbacks. An ideal infrastructure would:Provide deterministic performance for specified clients even at 4K when required without unnecessary overheads (no leave 50% free requirement)• Provide guaranteed performance under severe fault conditions• Never copy media for re-ordering• Guaranteed fast access allows live ‘play’ of edits• Provide high bandwidth open ‘files and folders’ access to media in the pool for clients not requiring deterministic access• Solve application file format, resolution, colour space and bit-depth issues without requiring multiple copies of media• Keep track of media relationships• e.g. know which four layers in a composite relate through to the final flattened result.• Provide facilities for storing and managing both open and dark metadata• Scale to any extent 9
  10. 10. Quantel ‘Dylan’ storage High-speed access Fault tolerance No-copy editing Frame-based media managementHigh Speed Access Dylan storage will support continual playout of realtime 4K, i.e. over one GByte/second (GB/s) and also error-free dual 2Kstereoscopic playback. The performance is maintained even with the diskover 90% full and irrespective of where the media is physically located onthe disk media. The disk never requires defragmenting so all thebandwidth is available to the user at all times.Fault tolerance In addition to dual power supplies the storage providesauto-rebuild of hot swapped disks without compromising performance.Where required dual parity protection can be implemented to protectagainst the failure of a second disk in an array while another is rebuilding.Again this does not impact performance.No copy editing The disk is capable of playing out media in any order inreal-time. It does not need to copy or move media in order to play outedited selections of shots. Multiple edited clips can refer to the samemedia. This technique makes storage incredibly efficient as the mediaonly exists once on the disk irrespective of how many times it is used.Frame-based media management To implement no-copy editingrequires a strong media management mechanism or inefficiencies areeasily reintroduced. The media management tracks each usage of everyframe, this ensures that long rushes are not locked from deletion simplybecause a few frames are used elsewhere in an edit and also that eachuser can safely delete unused material as the system will not deleteframes if they are being used in other clips. Both the above mechanismsare completely transparent to the user, the storage manages the processwithout any user input allowing the user more creative (billable) time andto spend less (non-billable) time on media and disk management. 10
  11. 11. ‘Genetic Engineering NAS/SAN LAN Audio ‘GenePool’ WorkspaceGenetic Engineering infrastructure allows multiple Quantel systems toshare the same ‘GenePool’ workspace. This shared workspace replacesthe direct attach storage. Each system accessing the pool retains exactlythe same capabilities as it would have with direct attach storage – thereare no compromises that have to be made to benefit from the sharedinfrastructure.In order to increase reliability and minimise system components there isno storage controller required, each mainframe manages its own storagejust as it does with direct attach workspace. Audio is stored in a separatedisk array connected by fibre channel to each mainframe. Newmechanisms are provided to ensure each system knows the current stateof the free space so there is no risk of two systems attempting to write tothe same free space. This inter-system communication takes place overthe LAN whenever space needs to be allocated. This method alsoautomatically provides fault tolerance should a mainframe becometemporarily unavailable.Due to the fibre channel topology each mainframe has access to the samedisk bandwidth as it would have with direct attach storage so itsperformance remains unchanged. In the above diagram each system canreliably and deterministically play 4K (or could play for example Stereo3D)without any impact on the systems’ operation. So for example one systemcan be doing a client-attended grading session, another can be performingquality control and the third playing out a 4K stream as HDRGB toHDCAMSR for a high quality deliverable. There is only ever one copy ofany particular media and each system can, in theory, have independentaccess to it. 11
  12. 12. Teamworking in Post NAS/SAN LAN Movie ‘Sam’ Audio File System Presentation Shared WorkspaceIf the GenePool infrastructure only provided Quantel to Quantel sharing itwould be a useful development for the post and DI pipeline but this is onlyhalf the story. As has already been stated Post, DI and BroadcastCreative Services today are about teamworking and the GenePoolinfrastructure integrates any system capable of working with media instandard file systems.A shared access product, Sam, provides open read/write access to mediain the GenePool.Using CIFS (Common Internet Filing System) third party applications,running Linux (2.6 Kernel) or Windows XP/Vista or Mac OSX can gainread/write access to media in the shared pool. There is no modification orspecial API required, any application that can access media over anetwork will be able to access the shared pool ‘out of the box’. The SamCIFS server supports multiple simultaneous clients each accessing themedia at the same time without blocking. Depending on configuration andthe network Sam can deliver several hundred MB/s to support 3rd partyapplications. Of course any file i/o activity does not impact on theperformance of the Quantel mainframes connected to the shared pool. 12
  13. 13. Shared inventory view Sam Access to: flattened files and ingredients Storage automatically tracks and manages media relationships Virtualise asset in different formatsThe above four layer composite is presented not only as a flattened file but alsoas a series of ingredients. This allows 3rd party systems to not only access themedia itself but also to access the history of how the media was created, allwithout any external media management system. This is a truly powerfulenvironment for VFX or Broadcast Creative services. 13
  14. 14. File virtualisation Sizing: high quality up or down-res Colorspace: YUV to RGB, 601 to 709 Bit depth: 16, 10 and 8 bit with dynamic rounding DPX handling: data packing/unpacking Colorspace Bit Depth Shared High YUV-RGB Dynamic Nx Disk DPX CIFS Workspace Quality RGB-YUV Rounding 2Gb FC interface Packing Presentation Pool Sizing 601-709 On 709-601 truncationA further aspect of Sam is to virtualize media, initially to differentresolutions and a common RGB colorspace but in the future to differentfile formats and bit depths. For example a clip that contains mediaoriginally from Digital Betacam (SD 4:2:2) from film (2K 4:4:4) and from.r3D Red camera files, can be presented to the outside world as if it wasall HD RGB in dpx, Tiff or non compressed Quicktime files. Sam usespurpose-built hardware to handle the computationally intensiveconversions on-the-fly as the media is read by the 3rd party system.As always, no new media is created on disk during these operations.Each application simply has access to the media in the format it needs itwhen it needs it without having to explicitly manage file conversions. Howthe clip is virtualised is controlled by modifying an associated XML file.A ‘distribute’ function on each workstation then allows media to be re-formatted and made available for third party systems without anyrendering – for example an HD clip can be made available in SD to adesktop application that cannot play back HD. 14
  15. 15. Typical Post applicationA VFX facility can use multiple desktop VFX systems each accessing media inthe GenePool. Media does not have to be transferred to the desktop systemsthey can work direct on the media in the shared pool, this greatly simplifies mediamanagement and also makes it straightforward to see an overall view of thecurrent state of the work in progress as all the media is one location and can beinstantly conformed for viewing. Full history remains available and files are neverflattened making changes much easier than today. 15
  16. 16. Locking image qualities together Work done on one file type reflected in others Files may be real or virtual Requires Robust identity model Virtual filing system This is crucial for a scalable broadcast workflow Web Desktop SD HDEverything we’ve discussed so far relies on a robust relationship betweendifferent qualities of media, whether those files are real or virtual. AllQuantel solutions are built on an identity model, which is the subject ofanother paper[] which provides this relationship.This is critical to Quantel’s broadcast server workflow, where broadcastand proxy media are held side-by-side on the same storage. 16
  17. 17. Broadcast solution requirements Short timescales Lots of users Different skills Teamworking in Post Range of file formats Different sources Multi-platform output SD, HD….3D?News is only news if it’s current. So a solution must be capable of publishingcontent quickly. Sports highlighting has even faster reaction times.In broadcast installations there’s typically a (relatively) large number of users,with different roles and skill-sets.Incoming content will be in a wide variety of file formats, image sizes, frame-rates. Lots of sources will arrive at the same time and must be accommodated.Outlets to TV, Web, Mobile must be provided – each with the rapid responserequired by news itself.Most TV news broadcasting in the world is still SD and all broadcasters havelegacy archives of SD content - but acquisition is turning rapidly to HD and mustbe handled efficiently.It’s probably a fair prediction that 3D news is a way off, but sport will be theresoon and other genres, like home shopping channels, can see the benefits. 17
  18. 18. Shared workflow for live TV Sources Workflow Output Journalists Editors Producers Cameras Production Graphics Directors Managers AnchorsLet’s remind ourselves of the workflow requirements for live broadcasting:Content comes from diverse sources; is processed by a cross-discipline teamand output to a range of platforms. TV is still predominant, but outlets to fixed andmobile computers/ hand-held devices are growing rapidly.The diagram shows a relationship between the different groups – they don’t actas an individuals, they’re a team. They need instant, uncontested access to themedia. They need to be able to share their work within the groups and with thewider team. 18
  19. 19. Collaborative working Desktop Database Desktop Editors Desktop Editors Desktop Editors Desktop Proxy files Editors Editors Broadcast File Video Proxy File Craft Craft Editors Broadcast files Editors Transcode ? Dylan storage Broadcast and Proxy files locked together Large numbers of workstations with instant, uncontested access Collaborative workflowHow do we make content available to large numbers of users distributed arounda production facility?The Quantel broadcast server is built around the same ‘Dylan’ storage describedabove.Video ingest is fed to a dual encoder which simultaneously creates a broadcast-quality and proxy file, linked by a single ID. Both files are stored on the samestorage with a separate database to hold both technical and essence metadata.Client workstations are supported over gigabit Ethernet connections. Desktopeditors working with proxy files; craft editors working with full-quality media. TheIdentity model guarantees a frame-accurate relationship between proxy andbroadcast content. 19
  20. 20. Make it fast Use an Identity model to represent every frame of stored media 1 2 3 4 5 6 7 8 9 10 Edits can be pointers to the stored frames 1 2 3 4 5 6 7 8 9 10 In Out Managed rendered sequences as ‘Deltas’ and add only these to the storage 3 4 5 6 7 8 A B C Use these techniques to keep data copying and movement to a minimumIt is beyond the scope of this paper to cover the subject in exhaustive detail, but itis necessary to highlight the design background of a fast, responsive sharedworkflow solution.We make a shared workflow solution fast and responsive by minimising therequirement to copy and move large media files.Every incoming file – whether acquired as video or via a network connection – issplit into individual frames. Each file is assigned a unique ID and each frame isindexed by counting from the start of the file. Thus, every frame can bereferenced, as can every piece of metadata attached to a frame or range offrames.Edit decisions can then be referred to those frames, allowing a simple subclip tobe created by simply storing the In and Out frames.In this way, edits based solely on server-held content are ready to play or exportimmediately with no new files created.Any new sequences, like effects, transitions or keys, create what we call ‘DeltaFrames’, the difference between the original media and the edited clip. Onlythese new frames are added to the storage. The database will register a logicalclip which comprises the original file plus the deltas and use this information onplayback or file export. 20
  21. 21. SD and HD Held natively Edited together Converted on output as required SD output SD sources HD sources HD output Auto size & ARC EditingThere are advantages to holding SD and HD content in native file formatand resolution, notably efficiency of storage.Editing workstations connected to the Quantel server may assemble atimeline of cuts, transitions or keys using any combination of SD and HDcontent. The edits are created and stored using the pointers plus ‘Delta’method described above. Video ports and FTP export modules areconfigurable and may be formatted to be SD (4:3 or 16:9) or HD. Contentis up or down rezzed on the fly during the playback / export process. Fileconversion and MXF wrapping is also applied live on export.. 21
  22. 22. People make TV Different jobs Different skill-sets Teamworking in Post Graduated application set Viewing Basic cut editing News editing Craft editing / effects Final Cut ProIt’s important to recognise that TV is not made by technology; it’s made by peopleusing technology.Quantel offers a range of editing tools, targeted at the different tasks which makeup TV production and the range of editing skills held by the operators.So, a simple viewing and logging tool, with basic drag and drop editing capability.A cuts-only editor, with sufficient functionality to start and finish a news or sportsstory. No video modifications in here, but audio tools including level controls andvoice-over recording.A news editor equipped for all but the most sophisticated features. Including toolsto fix the kind of problems news people hit every day. Like disguising faces; fixingcolour-balance errors or adjusting badly-exposed shots.Finally, a full effects editor with independent storage and hardware processing.In response to demand, Quantel have added Apple’s Final Cut Pro to theworkflow. 22
  23. 23. Efficiency What are the components of a typical News/Sports broadcast? Headlines, teases, bumpers, LVOs Packaged storiesThe design of our range of editing tools was considered alongside thereal-life requirements of live TV production.A news broadcast, for example contains many items of different lengths;different degrees of sophistication and different timescales.Many items – like headline sequences, the stories voiced live by theanchor (known as LVO – Live Voice-Over- in some parts of the world) andthe ‘tease’ items shown just before a commercial break – are short. Theseare perfectly suited to a simple drag and drop desktop workstation. Thetraining requirement is minimal, so a producer can learn to use italongside their scripting tools and take pressure off the craft editingresources.Our Viewer or Cuts-only editor is also a perfect rough-cutting or ‘offline’editor. Edits begun on the desktop may be accessed by the craft editors –including Final Cut Pro – for finishing. 23
  24. 24. Efficiency Sharing and delegating Jobs View, Log Editing Skills Heads, Opens, Bumpers, Review View View View View LVO’s, simple edits Cut Cut Cut Package editing Edit Edit Edit Animations, features, promos FCP Edit +A hierarchy of editing tools can be used to ‘filter’ the jobs flowing from theproduction.Some may be started and finished at the simplest level – like theheadlines described above.Others may be passed on to a higher level of competence for finishing.This is an important contrast with the ‘traditional’ idea of an editing poolstaffed entirely with trained editors with sophisticated workstations. This isextremely wasteful of resources. Our model allows for larger numbers ofsimpler, inexpensive workstations, with each contributing to the stream oftasks and leaving the craft facilities to dedicate themselves to high-qualityproductions. Thus, the quality of the output may be increased. 24
  25. 25. Quantel sQ server workflow ENPS Project sharing Playlist control Status feedback sQ View sQ Cut Desktop viewer Desktop editor PCR control Proxy media Record SD video Control HD video Quantel sQ server Broadcast media File Output WWW sQ Edit sQ Edit Plus Final Cut Pro News editor Craft editor Craft editor File Transcode ArchivePutting all this together – the shared workflow model is superficially verydifferent from Post, with some common technical elements and designphilosophy.Content is acquired and stored on a common pool. A range ofworkstations – with a common project structure – is arranged around thisstorage.Separate, less-agile storage may be used for mid- or long-term archiving,using an MXF file exchange to off-load and restore content.The shared storage in the server is designed to be scalable on threelevels:• Numbers of clients• Number of Input/Output nodes• Quantity of on-line storageUsers may work with newsroom management tools, like ENPS, to buildrundowns, write scripts etc. The rundowns may be linked to PCR playoutusing the MOS protocol.Video playout may be specified to be SD, HD or both at the same time.Separate FTP outputs may be scripted to deliver content in any file format,image size and wrapper, suitable for web or mobile distribution. 25
  26. 26. Conclusion Quantel has shared workflow solutions tailored to the requirements of the Post and Broadcast users Quantel philosophy is to empower creativity while keeping the engineering where it belongs – in the machine room Teamworking in Post 26
  27. 27. Thank you Trevor FrancisWorldwide Marketing Manager Quantel Ltd Newbury, UK 27