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    "msgid": "<20260703224817.15650-1-ballen4705@googlemail.com>",
    "date": "2026-07-03T22:48:15",
    "name": "[v2,0/2] libcamera: Add SensorSequence request metadata control",
    "submitter": {
        "id": 321,
        "url": "https://patchwork.libcamera.org/api/people/321/?format=api",
        "name": "Bruce Allen",
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            "date": "2026-07-03T22:48:15",
            "name": "libcamera: Add SensorSequence request metadata control",
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        "From": "Bruce Allen <ballen4705@googlemail.com>",
        "To": "libcamera-devel@lists.libcamera.org",
        "Cc": "Bruce Allen <ballen4705@googlemail.com>",
        "Subject": "[PATCH v2 0/2] libcamera: Add SensorSequence request metadata\n\tcontrol",
        "Date": "Fri,  3 Jul 2026 23:48:15 +0100",
        "Message-ID": "<20260703224817.15650-1-ballen4705@googlemail.com>",
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    },
    "content": "Hi,\n\nThis v2 series follows up on my v1 submission that exposed the Unicam\nfrontend sequence as an RPi vendor control [1], and Kieran's feedback that\nthis should be a standard metadata control across all platforms [2].\n\nThe series revives the approach from Kieran's 2021 RFC \"Request metadata:\nSensorSequence\" [3], updated for the current control_ids_core.yaml layout\nand additional pipelines. Compared with that original 8-patch series, this\nsubmission is limited to the control definition, pipeline plumbing, and\napplication documentation (no cam/qcam/gstreamer changes).\n\nChanges since v1:\n- Define controls::SensorSequence in control_ids_core.yaml (int64_t, out)\n  instead of controls::rpi::SensorSequence in control_ids_rpi.yaml\n- Populate the control in every pipeline handler that already reports\n  SensorTimestamp (simple, ipu3, rkisp1, rpi/vc4, rpi/pisp, mali-c55,\n  imx8-isi, uvcvideo, vimc)\n- Document SensorSequence in the application developer guide\n\nMotivation (unchanged from v1): applications diagnosing frame loss need a\ncounter tied to sensor-side capture, not just delivered-frame or request-\nqueue sequence. Gaps in SensorSequence indicate frames that did not reach the\ncapture device stream before the previous request completed. Python bindings\nfollow from existing pycamera codegen.\n\nTested: patch applies cleanly to master @ 709ad59; builds with\n-Dpipelines=rpi/vc4 -Dipas=rpi/vc4 -Dpycamera=enabled. Verified on\nRaspberry Pi CM4 that monotonic SensorSequence detects dropped frames.\n\n[1] https://lists.libcamera.org/pipermail/libcamera-devel/2026-June/059669.html\n[2] https://lists.libcamera.org/pipermail/libcamera-devel/2026-June/059681.html\n[3] https://patchwork.libcamera.org/project/libcamera/list/?series=2822\n\nCheers,\nBruce Allen"
}