reVTMD: NARA AudioVisual Metadata Extension Schema. A reVTMD expression contains technical and process metadata that describes a digital video object. A reVTMD element may either contain a 'file' or 'files'. The 'files' element is a container for multiple 'file' elements. Use 'files' only when a single media representation is comprised of multiple files. This optional attribute is intended to store a timestamp referring to when the record was initially created. This optional attribute may be use to identify A type for describing technical characteristics of a video object. The number of bits of sample depth, e.g., 8, 24, etc. The video sampling format used in a digital video file. (in terms of luminance and chrominance), e.g., 4:2:0, 4:2:2, 2:4:4, etc.) The signal format of a video source item e.g. NTSC, PAL, SECAM. The 'role' element defines the generic use or task performed by a given generation of the media or tool used in the processing of the media. Values may include: 'source object', 'playback device', 'capture device', 'capture software', 'operating system', etc. A free text string for internal use to clarify technical aspects of the coding history record. This string may not contain commas (use semicolons instead) or line breaks. The manufacturer of the tape, file, device, tool, software or piece of technology described in the coding history record. The name of the model of the tape, file, device, tool, software or piece of technology described in the coding history record. For products use the commericial name of the product, for tape formats use the name of the physical format (suggested vocabulary: http://metadataregistry.org/concept/list/vocabulary_id/145.html) When applicable, this element may store the serial number of the object described in the coding history record. The 'signal' element describes any standardized audiovisual interface that is used to transmit the signal between tools or elements. Examples include 'SDI', 'HD-SDI', 'Component', 'Composite', 'IEEE 1394'. The 'version' element expresses the version number of the software, tool, or object used in the process. The codec identifier of the video encoding. It is recommended to express video encoding using the fourCC (four character code). See: http://www.fourcc.org/codecs.php. The codec identifier of the audio encoding. It is recommended to express audio encoding using the twoCC (two character code) or fourCC (four character code). The average rate of the presentation of video samples. Express in frames per second. The rate of the presentation of audio samples. Express in Hertz. The structure and type of storage for video pixel data. Typically this denotes the colorspace, bitdepth, endianness, channel order and whether the format is planar or palletted. Examples include uyvy422, yuv422p, rgb24. This element expresses the data rate of the encoding video data over time. Express as the bit rate in bits per second. This element expresses the data rate of the encoding audio data over time. Express as the bit rate in bits per second. This element expresses the sampling size of the encoding video data. Express as the bit depth used per channel rather than per pixel. This element expresses the sampling size of the encoding audio data. Express as the bit depth used per channel rather than per stream. Document here any special settings utilize in this step of the process. info about the way the file was created Name of the creator of the compression application. Based on pbcore:instantiationPhysical / pbcore:instantiationDigital Denotes a value not contained in a restrictive vocabulary when the value is set to 'Other'. Denotes a value not contained in a restrictive vocabulary when the value is set to 'Other'. The nominal attribute is used to express any nominal value of rate expressed within the file (which may not be the actually rate), such as a nominal data rate expressed in the header of an mpeg2. Indicator that the measurement is constant or variable. The type of tracking code, e.g., system number, actual shelf numbers, bar-code, file identifier, track identifier, etc. Use the type attribute to declare the source or authority of the identifier. Based on pbcore:instantiationIdentifer / pbcore:essenceTrackIdentifier For management of any dates associated with the file, including creation or modification dates or dates embedded within the file. Based on pbcore:instantiationDate Elapsed time of the entire file, expressed using ISO 8601 syntax; see http://www.w3.org/TR/NOTE-datetime. Type of security applied to a digital video file e.g. password, encryption, hidden, etc.... The size of the file or track measured in bytes. Data rate of the compressed data over time expressed in bytes per second. Storage of the initial timecode value (if present). Method for recording timecode on the video source item Type of timecode recorded on video source item, e.g., SMPTE dropframe, SMPTE nondropframe, etc.. Use of the digital video file, e.g. Master, Service, Preview, etc..... Use Other if none of the preceding values pertains and clarify the use in the otherUse element Presented color of the digital video file. Use Other if none of the preceding values pertains and clarify the color in the otherColor element The definition and vocabulary are adopted from PBCore. frame.type: Complex Type for recording the size of a frame in a digital video file. frame.type has 6 elements pixelsHorizontal, pixelsVertical, PAR, DAR and rotation. The horizontal dimension of a frame in pixels. The vertical dimension of a frame in pixels. Pixel aspect ratio (present as a ratio or decimal). Display aspect ratio (present as a ratio or decimal such as 4/3 or 6/9 or 1.33333). The rotation in a decimal value (express of a percentage of clockwise rotation). The number of frames per second at which the video source item was digitized. Location of the referenced file Indicator of the presence of sound in the file or track. The sound field indicates whether a representation of sound is present in a file or track; for example, a 4 track DV file may have 4 audio tracks but only have a representative sound recording on the first two tracks and no audio recording on the last two tracks. Order of bit significance in a byte from left to right. To express whether the samples values is signed or not, meaning does zero represent the initial sample value or the middle sample value. checksum.type: Complex Type for recording the type of messageDigest used for a file. checksum. Type of messageDigest used. The datetime when the checksum was calculated and applied An element for storage of other pieces of metadata associated with the object or track, use the type attribute to clarify the meaning of the annotation value. Based on pbcore:instantiationAnnotation / pbcore:essenceTrackAnnotation