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MediaConch's sample digitization policy checks Matroska v4+, a unique ID, FFV1 3.4+, GOP size 1 and slice CRCs, plus SD geometry.\n\nCurator qualifications: Specifications and policy read 2026-10-22; no files encoded or hashed. framemd5 wording and FADGI 2014 comparison page from producer reading.\n\nLimitations: Specifications and policy read 2026-10-22; no files encoded or hashed.\n\nEvidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.","citations":[{"url":"https://ffmpeg.org/ffmpeg-formats.html","note":"ffmpeg-formats.html (live) crc and framecrc muxers; MediaConch_SourceCode 93bd6874 Tools/Policies/sample_policy_4_mkv_ffv1_digitization.xml rule names"},{"url":"https://github.com/MediaArea/MediaConch_SourceCode/blob/93bd68748f5f5d3c5fa32655ea43c83fad95c650/Tools/Policies/sample_policy_4_mkv_ffv1_digitization.xml","note":"ffmpeg-formats.html (live) crc and framecrc muxers; MediaConch_SourceCode 93bd6874 Tools/Policies/sample_policy_4_mkv_ffv1_digitization.xml rule names"},{"url":"https://www.digitizationguidelines.gov/guidelines/video_reformatting_compare.html","note":"ffmpeg-formats.html (live) crc and framecrc muxers; 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