Overview
ISO/IEC 23001-10:2020 specifies a standardized storage and carriage format for timed metadata in files based on the ISO base media file format (ISO/IEC 14496-12). Published by ISO/IEC, this MPEG systems technologies part defines how to embed time-aligned metadata such as video quality metrics, energy/green metadata, and coordinate/ROI information in metadata tracks so they can be associated with media tracks for use cases like dynamic adaptive streaming and power-aware media consumption.
Key Topics and Requirements
- Timed metadata storage: Metadata are stored as metadata tracks within the ISO base media file format and linked to the media track using a 'cdsc' (content describes) track reference.
- Quality metrics carriage: Defines a sample entry type ‘vqme’ (QualityMetricsSampleEntry) and a QualityMetricsConfigurationBox that declares:
- field_size_bytes - constant byte size per metric value
- metric_count and a list of metric_code identifiers
- Samples are arrays of metric values padded to the declared field size.
- Defined quality metrics: PSNR, SSIM, MS-SSIM, VQM, PEVQ, MOS, Frame Significance (FSIG), etc. Example: PSNR metric code name is ‘psnr’ and is stored as an unsigned 16-bit integer per sample.
- Green metadata: Support for energy-related metadata including decoder power indication and display power reduction entries to enable energy-efficient media consumption.
- Coordinates and ROI: Defines carriage of coordinate data (e.g., 2D Cartesian coordinates) and encoded regions of interest (Annex A), useful for ROI-based processing and adaptive encoding strategies.
- Interoperability rules: Only codes defined in the standard shall be used; metadata codec parameter per RFC 6381 for quality tracks must be set to ‘vqme’ with sub-parameters listing metric codes (e.g., 'vqme.psnr+mssm').
Applications and Users
- Adaptive streaming & CDN operators: Use timed quality metrics and ROI coordinates to make bitrate/resolution decisions and optimize delivery.
- Encoder and player developers: Embed and consume quality and green metadata for improved rate-control, device-aware playback and energy-saving strategies.
- QoE (Quality of Experience) measurement tools: Store per-frame or per-segment objective metrics (PSNR, SSIM, VQM) in media files for offline or on-device analysis.
- Device manufacturers / display vendors: Leverage display power metadata to implement fine-grained power reduction behaviours.
Related Standards
This part of ISO/IEC 23001 provides a practical, interoperable way to carry time-aligned quality, energy and coordinate metadata inside ISO base media files to support analytics, adaptive delivery, and power-aware playback.