EDCF Technical Support Group meeting at dcinex, Liège, Belgium on 13/11/2013

Transcription

1 EDCF Technical Support Group meeting at dcinex, Liège, Belgium on 13/11/2013 Meeting Location: dcinex s.a. Le Pole Image de Liège, Rue de Mulhouse, 36, B-4020, Liège, Belgium Meeting Minutes The meeting was chaired by Peter Wilson. Introduction After introduction by Peter to thank dcinex for their hospitality, and presentation of present members of the TSG, all attendees presented themselves to the group and completed an list. During the meeting two presentations about alternative content delivery and about the status of the Mezzanine File Format Workgroup were of particular interest and are provided in annex of the minutes. Pending issues from previous TSG meetings were again on the table, with brightness on screen, HFR, DCP delivery, and alternative content on the forefront. Alternative Content Delivery A presentation by Fabrice Testa from D-Sat (see annex 1) was followed by an open discussion. He insisted on the need for a professional solution at the uplink site for live events. Live streaming of embedded subtitles are not yet there but they are close. Expect the feature to become standard practice in Live TV and Live cinema require two different audio mixes as auditorium and home listening environments are very different. LFE in Cinema is LFE whereas the subwoofer channel for TV carries all low frequencies to compensate for small primary loudspeakers. D-sat is delivering live feeds to cinemas but also DCPs. A typical D-Sat down link decoder has 4 Terabytes of internal buffer so reception can be done transparently for the exhibitor: the partly received files are hidden from the theatre manager during transfer. When a DCP is ready to be used, it appears on the decoder hard disk. Discussion

2 Audio delays are still an issue on live alternative content at specific sites, and can be IRD and server specific. As broadcast teams are often managing the capture of live events, they are using 1080i50 format. As a consequence, de-interlacing artefacts are still an issue. The industry should push towards 1080p50 and the sooner the better. French Cinema goes IMF Francois Helt from H-T-Solutions and Hans-Nikolas Locher from the CST presented "Digital file format for conservation and exchange of cinematographic works" (see the full presentation in annex 2). IMF stands for "Interoperable Master Format". This format is also called "mezzanine format"; its standardisation is in the hands of the Mezzanine File Format Workgroup lead by the French CST and FICAM with participation from Éclair, H-T-S, and EVS. MFFW recommends a file format for exchange and conservation of Cinema Masters in order to facilitate exchanges between laboratories, to guide the digitizing work during the scanning and reconstruction phases of 35mm movies, and to define technical specifications of a digital duplicate" coherent with Digital Source Master (DSM). The archive format is NOT intended to be played back in real time. IMF includes lossless JPEG2000 compression for storage efficiency; sound is uncompressed (as in standard DCPs). Data corruption risks are supposed to be managed outside of the IMF spec, by the archive storage management system but nevertheless the order of data blocks inside the file may be important. Images in JPEG2000 format may be rearranged in two ways : CPRL or LRCP. The last one seems better for risk mitigation but is not widespread as all open source libraries such as Kakadu use the CPRL ordering method. Storage size is typically 147 GB for a 20 minutes reel. SMPTE DCP Introduction to Market An open discussion about this always hot topic. It seems that nobody is in a hurry to switch to SMPTE DCP. One of the main reasons is that US lags way behind Europe in terms of software updates so many US theatres are still unable to reliably play SMPTE DCPs. There are some pending issues with subtitles sync which should be fixed when equipment is upgraded. Organizing a European plug-fest for SMPTE DCP testing may be a good thing. This should be organized in a manufacturers-agnostic location. Possible locations may be Munich (at ZweiB) and Liège (at dcinex). We should reactivate the EDCF technical reflector to pinpoint the issues in order to present a unified voice to present European issues to the ISDCF. The naming convention is too short to cover all Movie Parameters and will be complemented with Metadata carried in the CPL. Provision should be made to include European Audiovisual Works Identifiers in this metadata as an option. This issue should be forwarded to ISDCF and/or SMPTE. Lunch and dcinex facilities tour An impressive collection of 12 or so Sony 4K and the same quantity of Christie 2K projectors were just arriving. Most probably the largest digital cinema equipment warehouse in

3 Europe! dcinex operate a warehouse with Quality Control and inspection facilities. They have a test facility with one of each projector and server type in their network. This gives them the possibility to configure and test software releases prior to distribution. They also run a service Network Operation Centre which allows for remote diagnostics and service / repair visit coordination. HFR Requirements 48 fps is now seen as normal, but what about archive frame rates? It seems that nothing moved, except maybe an Experimental project in the Netherlands trying to support 18 fps. According to SMPTE ST428-11:2013, the Additional Frame Rate standard now allows for 2D and 3D movies at 24, 25, 30, 48, 50 and 60 fps per eye, the last three being newly added by this amendment. This is an amendment to the SMPTE ST428-11:2009 Additional Frame Rates for D-Cinema standard. The text is available at: Next big alternative content event: The Dr Who 50th Anniversary special will be broadcast on November 23, 2013 in 3D and the episode will also be released in selected cinemas (in DCP format) in UK, Ireland, Germany, Russia, and selected locations in Australia, New Zealand and the USA. New Audio Systems There are two new emerging tridimensional surround sound formats: Dolby Atmos and Barco Auro-3D. The questions are: Will they be interoperable? and compatible with a single master format? Barco-Auro3D says it is possible but part of the problem is on the speakers side: there are as many loudspeakers configurations as there are theatres and the speakers configuration is outside of the SMPTE standard scope. An object-based standard may be the way to go but there is also merit in a simpler system. Dolby Atmos Connect (DAC) may be licensed for free. DAC is an audio-over-ethernet protocol based on a 2xGig-E Ethernet connection linking the audio processor and up to 48 loudspeakers (more than 48 are possible but you will need two audio processors). Auro3D distributes surround sound through a standard 5.1 mix, so it is natively compatible with the installed base equipment and can be included in SMPTE and Interop DCPs. Watermarking audio is still a pretty ambiguous topic. What will it become in a future object-based standard? Content made for broadcast is generally not suitable for cinemas. i.e. the LFE channel is too loud, rear channels are too weak,... How can we change that? LFE in Cinema is LFE whereas the subwoofer channel for TV carries all low frequencies to compensate for small primary loudspeakers. Should we make/require a specific mix for cinemas mandatory in live alternative content events? Brightness on Screen Measurement

4 Brightness (and lack of it) is still a big problem for 3D. Measurement is one of the weak points in the chain. Brightness is hampered by several often neglected factors such as projection booth port window transparency and light scattering. Usual spectrometers only give 7% accuracy. There is no protocol or standard procedure on how to measure brightness. The protocol should take into account lots of variables such as scene geometry. Equipment manufacturers are reluctant to promote measurement methods that may force them to revise their announced brightness. SMPTE has a standardisation group looking at this area and this group should be supported. They are not suggesting different light levels just a consistent method of measurement. DCP Delivery Options The Smartjog distribution setup was described. Problems can appear when other files than DCPs are present on the same disk or volume. suggestion should be made to server manufacturers to relax this constraint. On SONY servers, navigating the directories is difficult because the software is too rigid; the process is very time consuming. Satellite distribution is not really fast but is the best solution when fast Internet connection is not available: remote countryside areas, northern countries, isolated small towns,... Time of week is a factor for hard disk shipping as delivery over week-ends is often delayed. Festival Support Group Update There are three types of festivals : big ones (Cannes,...), medium ones with small budgets, and small ones that can afford to miss a single DCP here and there but often make compromises of delivery methods and/or quality. Some festivals require unencrypted DCP only in order to avoid KDM problems. Festivals need a clear set of guidelines and help to formulate rules on how DCP s are to be encoded and submitted. Festival personnel need education on how to write those guidelines, how to check and ingest DCPs, etc. Reminder If it was possible an automatic DCP checker would be very useful. 24p and 25p frame rates sometimes cause DCP audio and/or subtitles desynchronisation. The EDCF Revised Mastering Guide is available to download from the Members Area of the EDCF web-site since September. For Live events a technical guide is available from the UK Digital Television Group. Broadcasting Live Events to Cinema Recommendations for preparation, transmission, reception and presentation

5 Notes by Benoit Michel 13/11/2013 Attendees Peter Wilson HDDC Benoit Michel dcinex Mark Waldman dcinex Nick Watson Dolby Frank De Neve CineServer Mirko Heukemes dcinex Radoslav Markov Camera Ltd François Helt H-T-Solutions Jérôme Delvaux Barco Michihiro Tobita Sony Rich Phillips Arts Alliance Tammo Buhren ZweiB Manu Finck dcinex Alexandre Weiser dcinex Fabrice Testa D-Sat Wolfgang Ruppel Rhein Main University Angela Bungo Ecco gmbh Michael Gillessen dcinex Christophe Lemort dcinex Thomas Caspersen Nordisk Film Shortcut Hans-Nikolas Locher CST

6 Annex 1 Alternative Content Delivery

7 Annex 2 Digital file format for conservation and exchange of cinematographic works

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