ISO 26428-19:2011

Overview

ISO 26428-19:2011 specifies requirements for serial digital interface (SDI) signal formatting in digital cinema (D-cinema) distribution masters, focusing on additional frame rate levels AFR2 and AFR4. This standard defines how the image pixel structure for these frame rates, as detailed in ISO 26428-11, should be formatted and transmitted over 1.485 Gb/s dual link SDI (SMPTE 372M) and 3 Gb/s SDI (SMPTE 424M) interfaces. By ensuring compatibility and correct formatting, ISO 26428-19:2011 plays a critical role in the digital cinema post-production and distribution process, promoting interoperability across global digital cinema workflows.

Key Topics

• SDI Signal Formatting for AFR2 and AFR4: Defines the fixed SDI container size (2048 x 1080 pixel array) for both 25 fps and 30 fps progressive frame rates.
• Pixel Structure Conformance: Outlines requirements for arranging image data and padding within the SDI container, ensuring the image center aligns with the SDI container center.
• Padding and Data Coding: Specifies use of padding pixels and X’, Y’, Z’ color coding as defined in related standards, with explicit constraints on allowable code values.
• Synchronization Sequences: Describes the structure and use of Start of Active Video (SAV) and End of Active Video (EAV) digital synchronizing sequences to ensure valid frame and line identification during transmission.
• Progressive Segmented Frame (PsF) System: Includes provisions for transmitting progressive images over interfaces originally designed for interlaced video, facilitating backward compatibility in cinema workflows.
• Normative References: Aligns closely with other ISO and SMPTE digital cinema standards to ensure comprehensive coverage of image, audio, and metadata requirements.

Applications

ISO 26428-19:2011 is widely implemented in the digital cinema industry for:

• Digital Intermediate and Distribution Mastering: Ensuring D-cinema content is correctly formatted for both 25 fps and 30 fps delivery.
• Post-Production Workflows: Standardizing SDI output for DCDM (Digital Cinema Distribution Master) across various mastering, editing, and quality control systems.
• Cinema Content Distribution: Facilitating reliable transmission of high-fidelity digital cinema packages (DCPs) within and between studios, post facilities, and cinemas, especially when using diverse SDI-based networks.
• Equipment Interoperability: Supporting seamless integration of playback servers, projectors, and display devices that rely on SMPTE 372M or 424M SDI interfaces.

Organizations relying on consistent, high-quality digital cinema distribution workflows benefit from implementing ISO 26428-19:2011 by ensuring equipment compatibility and maintaining image integrity across international markets.

Related Standards

• ISO 26428-1:2008: Digital cinema (D-cinema) distribution master - Part 1: Image characteristics (SMPTE 428-1)
• ISO 26428-11:2011: Digital cinema (D-cinema) distribution master - Part 11: Additional frame rates (SMPTE 428-11)
• SMPTE 372M: Dual link 1.485 Gb/s SDI specification
• SMPTE 424M: 3 Gb/s SDI interface for higher bandwidth applications
• SMPTE 428 Series: Complete suite covering D-cinema image, audio, channel mapping, subtitles, and signal formatting

ISO 26428-19:2011 serves as an essential link in the broader landscape of cinema signal formatting standards, ensuring precise signal handling and facilitating future advancements in digital cinema technology.