Overview
ISO/IEC 23001-17:2024/Amd 1:2025 is an amendment to the international standard for MPEG systems technologies, specifically addressing the carriage of uncompressed video and images in the ISO base media file format. This amendment introduces high precision timing tagging, enabling reliable and high-resolution time labeling of media samples and items. Enhanced precision in time stamping supports various applications where synchronization, accuracy, and provenance of video and images are critical. This standard is maintained by ISO and IEC under the technical committee focusing on coding of audio, picture, multimedia, and hypermedia information.
Key Topics
- High Precision Time Tagging: Introduces a standardized method for labeling media content with timestamps based on International Atomic Time (TAI), expressed in nanoseconds from the TAI epoch.
- Quality and Status Metadata: Provides detailed metadata on the uncertainty, resolution, and synchronization state of the clock generating each timestamp.
- TAI and UTC Distinction: Explains the differences and conversion requirements between TAI and Coordinated Universal Time (UTC), including how leap seconds influence translation from one format to another.
- Synchronization Protocols: Defines how various time synchronization protocols-such as Precision Time Protocol (PTP, IEEE 1588), Network Time Protocol (NTP, RFC 5905), and GPS-relate to TAI-based timestamping.
- Data Structures for Time Tagging:
- TAIClockInfoBox: Captures metadata on the clock source, its precision, drift, and synchronization status.
- TAITimestampPacket: Provides the actual timestamp and status flags, including synchronization and modification indications.
- Sample and Item Timestamping: Defines separate mechanisms for associating TAI timestamps both with track samples and media items.
Applications
The amendment's high precision timing tagging mechanism is designed for a broad range of real-world and technical applications:
- Video Production and Broadcast: Ensures precise temporal alignment of video frames and uncompressed image samples when using multiple devices or in post-production workflows.
- Sensor Synchronization: Essential for industries like industrial automation, surveillance, scientific research, and autonomous vehicles, where correlation of data from multiple sensors or cameras is required.
- Forensic Analysis: High-accuracy timestamps support evidentiary requirements, establishing indisputable records of when content was captured.
- Augmented and Virtual Reality: Aligns different media streams and sensor data with nanosecond-level accuracy, vital for immersive user experiences.
- Scientific Imaging and Measurement: Facilitates synchronized measurements across distributed imaging equipment, useful in fields like astronomy or high-speed scientific photography.
- Interoperability: Supports interoperability in multi-vendor and multi-system environments through standardized metadata structures and conversion methods for common time protocols.
The standard also provides useful conversion formulas and data structures for integrating with devices using PTP, NTP, GPS, and POSIX time.
Related Standards
- ISO/IEC 14496-12: ISO base media file format - provides the foundational file structure in which uncompressed video, images, and their metadata-including TAI timestamps-are carried.
- IEEE 1588-2008: Defines the Precision Time Protocol, a core technology for network-based time synchronization.
- IETF RFC 5905: Specifies the Network Time Protocol, which is commonly used for synchronizing clocks over packet-switched data networks.
- Other Parts of ISO/IEC 23001 Series: Address complementary aspects of MPEG systems technologies for audio, video, data, and control.
By implementing ISO/IEC 23001-17:2024/Amd 1:2025, organizations and technology providers ensure robust, interoperable, and future-proof high precision time tagging for uncompressed video and images, supporting critical synchronization and provenance demands across diverse sectors.