DCI Specs - Digital Cinema Initiatives

5.3.4.2. Frame BoundariesThe Audio Track File is required to begin and end with complete frames that areassociated with its Image Track File to allow for a clean transition between reels. Theaudio data within the Track File shall be wrapped using KLV on an image frameboundary.5.3.4.3. Data Packing FormatThe Audio Track File is required to support uncompressed audio data.5.3.4.4. MetadataThe following metadata is required to be furnished with the Audio Track File:• Unique ID• Unique ID of corresponding plaintext track encrypted• Track type (i.e., audio)• Audio Sampling Frequency• Quantization bits (sample size)• Channel Count• Channel Mapping Labels• Data Packing Format• Frame Rate• Audio Frame count number (duration)5.3.5. Subtitle Track File5.3.5.1. IntroductionA Subtitle Track File contains, for example, the Subtitling essence data and itsassociated metadata. Each Subtitle Track File may contain any combination of text, fontreferences, and image references.5.3.5.2. Frame BoundariesThe Subtitle Track File is required to have the same duration as the playable region of itsassociated Image Track File.5.3.5.3. Timed TextAny Timed Text element is required to use an Open Type font.5.3.5.4. SubpictureSubpicture elements are required to use the PNG file format.5.3.5.5. MetadataThe following metadata is required to be furnished with the subpicture Track File:DCI Digital Cinema System Specification v.1.2 Page 52