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{
    "id": 24640,
    "url": "https://patchwork.libcamera.org/api/1.1/covers/24640/?format=api",
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    "msgid": "<20251014142427.3107490-1-stefan.klug@ideasonboard.com>",
    "date": "2025-10-14T14:24:15",
    "name": "[v1,0/4] libipa: agc: Fix constraints yTarget handling and add PWL support",
    "submitter": {
        "id": 184,
        "url": "https://patchwork.libcamera.org/api/1.1/people/184/?format=api",
        "name": "Stefan Klug",
        "email": "stefan.klug@ideasonboard.com"
    },
    "mbox": "https://patchwork.libcamera.org/cover/24640/mbox/",
    "series": [
        {
            "id": 5502,
            "url": "https://patchwork.libcamera.org/api/1.1/series/5502/?format=api",
            "web_url": "https://patchwork.libcamera.org/project/libcamera/list/?series=5502",
            "date": "2025-10-14T14:24:15",
            "name": "libipa: agc: Fix constraints yTarget handling and add PWL support",
            "version": 1,
            "mbox": "https://patchwork.libcamera.org/series/5502/mbox/"
        }
    ],
    "comments": "https://patchwork.libcamera.org/api/covers/24640/comments/",
    "headers": {
        "Return-Path": "<libcamera-devel-bounces@lists.libcamera.org>",
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            "from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id E7FBBBE080\n\tfor <parsemail@patchwork.libcamera.org>;\n\tTue, 14 Oct 2025 14:24:34 +0000 (UTC)",
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        "From": "Stefan Klug <stefan.klug@ideasonboard.com>",
        "To": "libcamera-devel@lists.libcamera.org",
        "Cc": "Stefan Klug <stefan.klug@ideasonboard.com>",
        "Subject": "[PATCH v1 0/4] libipa: agc: Fix constraints yTarget handling and add\n\tPWL support",
        "Date": "Tue, 14 Oct 2025 16:24:15 +0200",
        "Message-ID": "<20251014142427.3107490-1-stefan.klug@ideasonboard.com>",
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        "Sender": "\"libcamera-devel\" <libcamera-devel-bounces@lists.libcamera.org>"
    },
    "content": "Hi all,\n\nThis series introduces support for specifying the\nrelativeLuminanceTarget based on the current lux level by using a PWL\nfor the mapping. The typical use case is to ensure that images in a\nbright environment are regulated a tad brighter than images taken in a\ndark environment. This is a very subjective setting and should thereofre\nleft for the customer. Mainlining this feature was already tried here\n[1] but got rejected at that time because there was no direct user of\nit.  Meanwhile the lux algorithm got upstreamed and we have customers\nthat actually miss that feature. So I start another try of upstreaming\nit (Patches 1-2).\n\nDuring implementation it turned out that the yTarget of AGC constraints\nnever worked at all. So patches 3-4 fix that and also add PWL support\nfor the constraints which is sensible to do if we support it for the\nrelativeLuminanceTarget.\n\nBest regards,\nStefan\n\nStefan Klug (4):\n  ipa: libipa: pwl: Add swap() function\n  ipa: libipa: agc_mean_luminance: Change luminance target to piecewise\n    linear function\n  ipa: libipa: pwl: Add construction from initializer_list\n  ipa: libipa: agc_mean_luminance: Fix yTarget handling in constraints\n\n src/ipa/libipa/agc_mean_luminance.cpp | 113 ++++++++++++++++++++++----\n src/ipa/libipa/agc_mean_luminance.h   |  16 ++--\n src/ipa/libipa/pwl.cpp                |  25 ++++++\n src/ipa/libipa/pwl.h                  |   2 +\n src/ipa/rkisp1/algorithms/agc.cpp     |   1 +\n src/ipa/rkisp1/algorithms/wdr.cpp     |   3 +-\n 6 files changed, 136 insertions(+), 24 deletions(-)"
}