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23-504: DNxHD is a video codec intended to be usable as both an intermediate format suitable for use while editing and as a presentation format. DNxHD data is typically stored in an MXF container, although it can also be stored in a QuickTime container. On February 13, 2008, Avid reported that DNxHD was approved as compliant with the SMPTE VC-3 standard. DNxHD is intended to be an open standard, but as of March 2008, has remained effectively

46-445: A container format may be used to provide the appearance of a single file format to users of multimedia playback software. The differences between various container formats arise from five main issues: In addition to pure container formats, which specify only the wrapper but not the coding, a number of file formats specify both a storage layer and the coding, as part of modular design and forward compatibility . Examples include

69-486: A policy known as the Zero Divergence Directive (ZDD). This theoretically enables MXF/AAF workflows between non-linear editing (NLE) systems using AAF and cameras, servers, and other devices using MXF. From 2004 onwards, MXF was in the process of evolving from standard to deployment. The breadth of the standard was subject to lead to interoperability problems, as vendors implement different parts of

92-620: A proprietary Avid format. The source code for the Avid DNxHD codec is freely available from Avid for internal evaluation and review, although commercial use requires Avid licensing approval. It has been commercially licensed to a number of companies including Ikegami, FilmLight, Harris Corporation , JVC , Seachange, EVS Broadcast Equipment . On September 14, 2014, at the Avid Connect event in Amsterdam , Netherlands , Avid announced

115-554: Is "mxf ", including a trailing space. This list represents some examples of free and open source products that support the MXF standard: SMPTE's top standards page has information, for the ordering of CD-ROMs, which would hold formal copy of the SMPTE standards. Judging by SMPTE's index, all of the standards, referenced above, would be contained on those CD-ROMs, as available from SMPTE . IRT Test Center contains up-to-date information on

138-501: Is also used as part of the Digital Cinema Package for delivering movies to commercial theaters. MXF, when used in the form of "Operational Pattern OP1A" or "OPAtom", can be used as a container , wrapper or reference file format which supports a number of different streams of coded " essence ", encoded in any of a variety of video and audio compression formats , together with a metadata wrapper which describes

161-518: Is available to create and play QuickTime files containing DNxHD material. Since September 2007, the open source FFmpeg project is providing 8-bit VC-3/DNxHD encoding and decoding features thanks to BBC Research who sponsored the project and Baptiste Coudurier who implemented it. In July 2011, FFmpeg added 10-bit encoding support. DNxHD support is included in stable version 0.5 of FFmpeg, released on March 10, 2009. This allows Linux non-linear video editors Cinelerra and Kdenlive to use DNxHD. At

184-468: Is packed into big-endian dwords . Actual frame data consists of packed macroblocks using a technique almost identical to JPEG : DC prediction and variable-length codes with run length encoding for other 63 coefficients. DC coefficient is not quantized. The codec supports alpha channel information. The DNxHD codec was submitted to the SMPTE organization as the framework for the VC-3 family of standards. It

207-415: Is possible, as broadcasters develop application specifications they expect their vendors to implement. As of autumn 2005, there were major interoperability problems with MXF in broadcast post-production use. The two data-recording camera systems which produced MXF at that time, Sony 's XDCAM and Panasonic's DVCPRO P2 , produced mutually incompatible files due to opaque sub-format options obscured behind

230-560: Is unique in its support for DNxHD, and records directly to DNxHD encoded video. Such material is immediately accessible by editing platforms that directly support the DNxHD codec. The Arri Alexa supports DNxHD since November 2011 . Blackmagic Design HyperDeck Shuttle 2 and HyperDeck Studio support DNxHD as of 2012. AJA Video Systems has supported the DNxHD codec in its Ki Pro Mini and Ki Pro Rack recorders and players since 2012. A standalone QuickTime codec for both Windows XP and Mac OS X

253-614: The DNxHR codec to support resolutions greater than 1080p , such as 2K and 4K . On December 22, 2014, Avid Technology released an update for Media Composer that added support for 4K resolution, the Rec. 2020 color space, and a bit rate of up to 3,730 Mbit/s with the DNxHR codec. DNxHD was first supported in Avid DS Nitris (Sept 2004), then Avid Media Composer Adrenaline with

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276-532: The JPEG File Interchange Format (JFIF), for containing JPEG data, and Portable Network Graphics (PNG) formats. In principle, coding can be changed while the storage layer is retained; for example, Multiple-image Network Graphics (MNG) uses the PNG container format but provides animation, while JPEG Network Graphics (JNG) puts JPEG encoded data in a PNG container; in both cases however,

299-453: The April 2012 NAB show , Brevity introduced a customized algorithm for the accelerated transport and encoding of DNxHD files. DNxHD is very similar to JPEG . Every frame is independent and consists of VLC -coded DCT coefficients. The header consists of many parts and may include quantization tables and 2048 bits of user data. Each frame also has two GUIDs and timestamp. The frame header

322-471: The DNxcel option (Dec 2004) and finally by Avid Symphony Nitris (Dec 2005). Xpress Pro is limited to using DNxHD 8-bit compression, which is either imported from file or captured using a Media Composer with Adrenaline hardware. Media Composer 2.5 also allows editing of fully uncompressed HD material that was either imported or captured on a Symphony Nitris or DS Nitris system. Ikegami's Editcam camera system

345-518: The MXF file extension. Without advanced tools, it was impossible to distinguish these incompatible formats. Some of the incompatibilities were addressed and ratified in the 2009 version of the standard. MXF is used as the audio and video packaging format for Digital Cinema Package (DCP). It is also used in the STANAG specification documents. The file extension for MXF files is ".mxf". The Macintosh File Type Code registered with Apple for MXF files

368-472: The contained data. In these cases, programs usually emit an error message that complains of a missing codec, which users may be able to acquire. Container formats can be made to wrap any kind of data. Though there are some examples of such file formats (e.g. Microsoft Windows 's DLL files), most container formats are specialized for specific data requirements. For example, since audio and video streams can be coded and decoded with many different algorithms,

391-465: The different formats have different magic numbers – the format specifies the coding, though a MNG can contain both PNG-encoded images and JPEG-encoded images. The container file is used to identify and interleave different data types. Simpler container formats can contain different types of audio formats, while more advanced container formats can support multiple audio and video streams, subtitles , chapter-information, and meta-data ( tags ) — along with

414-428: The earliest cross-platform container formats were Distinguished Encoding Rules and the 1985 Interchange File Format . Although containers may identify how data or metadata is encoded, they do not actually provide instructions about how to decode that data. A program that can open a container must also use an appropriate codec to decode its contents. If the program doesn't have the required algorithm, it can't use

437-506: The material contained within the MXF file . Other "Operational Patterns" can contain or reference multiple materials, just like a simple timeline of a video editing program. MXF has full timecode and metadata support and is intended as a platform-agnostic stable standard for future professional video and audio applications. MXF was developed to carry a subset of the Advanced Authoring Format (AAF) data model, under

460-459: The standard or interpret misleading parts of the standard differently. MXF is fairly effective at the interchange of D10 (IMX) material, mainly because of the success of the Sony eVTR and Sony's eVTR RDD to SMPTE. Workflows combining the eVTR, Avid NLE systems, and broadcast servers using MXF in coordination with AAF are now possible. Long- GOP MPEG-2 material interchange between video servers

483-549: The status of the SMPTE documents. Container format (digital) A container format (informally, sometimes called a wrapper ) or metafile is a file format that allows multiple data streams to be embedded into a single file , usually along with metadata for identifying and further detailing those streams. Notable examples of container formats include archive files (such as the ZIP format ) and formats used for multimedia playback (such as Matroska , MP4 , and AVI ). Among

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506-646: The synchronization information needed to play back the various streams together. In most cases, the file header, most of the metadata and the synchro chunks are specified by the container format. For example, container formats exist for optimized, low-quality, internet video streaming which differs from high-quality Blu-ray streaming requirements. Container format parts have various names: "chunks" as in RIFF and PNG, "atoms" in QuickTime/MP4, "packets" in MPEG-TS (from

529-407: Was approved as SMPTE VC-3 after a two-year testing and validation process in 2008 and 2009: Material Exchange Format Material Exchange Format ( MXF ) is a container format for professional digital video and audio media defined by a set of SMPTE standards. A typical example of its use is for delivering advertisements to TV stations and tapeless archiving of broadcast TV programs. It

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