Sustainability of Digital Formats
Planning for Library of Congress Collections
Sustainability of Digital Formats
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| Introduction | Sustainability Factors | Content Categories | Format Descriptions | Contact | |
| Full name | ISO/IEC 15444-3:2007. Information technology -- JPEG 2000 image coding system -- Motion JPEG 2000 (formal name); Motion JPEG 2000 (common name) |
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| Description | Object-oriented file wrapper designed for time-based audio-visual information, including video, audio, and other tracks. In contrast to the temporal or inter-frame compression found in formats like MPEG-2, MPEG-4_V, and MPEG-4_AVC, MJP2 frames are represented as separate entities encoded with J2K_C (lossy or lossless). The standard permits creators to declare profiles; the main specification defines the Simple Profile (described in the Notes to this description), while amendment 1 specifies two archive-oriented profiles. Amendment 1 also includes an annex that highlights the format's value to an archive that plans to ingest instances of digital cinema packages DCP_1_0 and its successors as standardized by SMPTE. Although the format is oriented to newer progressive-scan video streams and "the use of interlaced material is not recommended" (annex E.2), the specification's annex D provides guidance on the inclusion of interlaced streams. |
| Production phase | Generally used for middle- and final-state archiving or end-user delivery. |
| Relationship to other formats | |
| Subtype of | ISO_BMFF, ISO Base Media File Format |
| Has subtype | Motion JPEG 2000 Simple Profile, not described at this site at this time |
| Has subtype | Motion JPEG 2000 Motion Picture Archive Preservation Format Profile, not described at this site at this time |
| Has subtype | Motion JPEG 2000 Motion Picture Archive Access Format Profile, not described at this site at this time |
| LC experience or existing holdings | None |
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| LC preference | For preservation reformatting, the Library of Congress' Packard Campus for Audio-Visual Conservation has chosen MXF_OP1a_JP2_LL (lossless JPEG 2000 wrapped in MXF operational pattern 1a). |
| Disclosure | Open standard. Developed jointly by the Motion Pictures Expert Group (MPEG), a working groups within the ISO/IEC committee structure formally known as ISO/IEC JTC 1/SC 29. |
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| Documentation | ISO/IEC 15444-3:2007. Information technology -- JPEG 2000 image coding system: Motion JPEG 2000. Also ISO/IEC 15444-3:2007, Amendment 1 (2010): Additional profiles for archiving applications. |
| Adoption | No adoption by broadcasters or other media-industry professionals known to the compiler of this description; comments welcome. There are, however, descriptions and tools for the creation of Motion JPEG 2000 animations in the field of astronomy, using the IDL language, from NASA. |
| Licensing and patents | Annex H of the standard reports that "compliance with this document may involve the use of a patent concerning JPEG 2000," "the holder of this patent right . . . is willing to negotiate licences under reasonable and non-discriminatory terms." The patent holder is identified as Sony Corporation. For additional information, see also ISO_BMFF. |
| Transparency | Depends upon tools to read; will require sophistication to build tools. |
| Self-documentation | The structure includes boxes and headers that contain the technical metadata needed to manage the media streams. There are many types of boxes and headers, including this example : "Motion JPEG 2000 video is stored in tracks . . . the exact format of the video is declared by the sample description." Sample descriptions are the topic of section 6.1 of the standard. |
| External dependencies | None. |
| Technical protection considerations | See ISO_BMFF. |
| Moving Image | |
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| Normal rendering | Good support. The format supports timescales that manage the playout of time-based media streams. |
| Clarity (high image resolution) | Excellent potential; the outcome will depend on the type and extent of compression, and the encoder used. |
| Functionality beyond normal rendering | The specification discusses features like composition (the mixing or matrixing of tracks), random access, and fragmented movie files. Options for 3D picture data not investigated for this description. |
| Sound | |
| Normal rendering | Good support. |
| Fidelity (high audio resolution) | Excellent; the format supports LPCM encoding (as "raw" or "twos-complement" data) with no stated limit on sampling or bit depth. The simple profile, however, is limited to a single audio track, not to exceed 48 kHz and 16 bits. The format also supports tracks using any encoding specified in MPEG-4; for information, see MP4_FF_2. |
| Multiple channels | The support for multiple tracks permits the use of multiple audio streams and/or individual streams encoded in structures like 5.1 (e.g., AAC_MP4 from the MPEG-4 family). |
| Support for user-defined sounds, samples, and patches | Not investigated for this description. |
| Functionality beyond normal rendering | See beyond-normal-rendering note in the video section above. |
| Tag | Value | Note |
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| Filename extension | mj2 mjp2 |
From the specification; mj2 is preferred. |
| Internet Media Type | video/mj2 |
From http://www.ietf.org/rfc/rfc3745.txt |
| Magic numbers | 12 byte string: X'0000 000C 6A50 2020 0D0A 870A' |
"For all JPEG-2000 family files," from http://www.ietf.org/rfc/rfc3745.txt |
| File type brand (ISO Base Media File Format) | mjp2 |
In the ISO_BMFF file type box, "indicates unrestricted conformance to this specification," from Annex A of the specification. |
| File type brand (ISO Base Media File Format) | mj2s |
In the ISO_BMFF file type box, "indicates indicates the simple Motion JPEG2000 profile," from Annex A of the specification. |
| File type brand (ISO Base Media File Format) | mpap |
From amendment 1, brand for the Motion JPEG 2000 Motion Picture Archive Preservation Format. |
| File type brand (ISO Base Media File Format) | mpaa |
From amendment 1, brand for the Motion JPEG 2000 Motion Picture Archive Access Format. |
| General | An early expression of the connection between MJ2_FF and digital cinema is provided by Siegfried Foessel's 2002 slide show Motion JPEG2000 and Digital Cinema. In 2005, Glenn Pearson, associated with the National Library of Medicine, organized a symposium on Motion JPEG 2000 and its relevance to video reformatting (generally understood as having analog videotapes as a source); in the same year, Pearson and Michael Gill co-published an analytic paper on the format. The Motion JPEG 200 Simple Profile includes the following elements: • Exactly one video track is present. • At most a single audio track, using only 8 or 16-bit raw audio, is present. • Each track shall have exactly one sample description, used by all samples. • The sample rate of the audio, if present, shall not exceed 48 kHz. • The frame rate of the video shall not exceed 30 frames per second. • The video codestream profile shall be profile O for both the motion sequence and the still image, if present. • The file is self-contained; no data references are used, and therefore all media data is contained within the single file. • The media data in the Media Data Box(es) is placed within the box(es) in temporal order. • If more than one track is present, the media data for the tracks is interleaved, with a granularity no greater than the greater of (a) the duration of a single 'sample' (in file format terms) or (b) one second. • The transformation matrices used are restricted to uniform scaling and rotation by multiples of 90 degrees. |
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| History | The underlying ISO_BMCC format and this subtype owe a strong debt to Apple's QuickTime. |
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