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{
    "id": 14188,
    "url": "https://patchwork.libcamera.org/api/1.1/covers/14188/?format=api",
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    "msgid": "<20211020104212.121743-1-umang.jain@ideasonboard.com>",
    "date": "2021-10-20T10:42:08",
    "name": "[libcamera-devel,v5,0/4] Async Post Processor",
    "submitter": {
        "id": 86,
        "url": "https://patchwork.libcamera.org/api/1.1/people/86/?format=api",
        "name": "Umang Jain",
        "email": "umang.jain@ideasonboard.com"
    },
    "mbox": "https://patchwork.libcamera.org/cover/14188/mbox/",
    "series": [
        {
            "id": 2640,
            "url": "https://patchwork.libcamera.org/api/1.1/series/2640/?format=api",
            "web_url": "https://patchwork.libcamera.org/project/libcamera/list/?series=2640",
            "date": "2021-10-20T10:42:08",
            "name": "Async Post Processor",
            "version": 5,
            "mbox": "https://patchwork.libcamera.org/series/2640/mbox/"
        }
    ],
    "comments": "https://patchwork.libcamera.org/api/covers/14188/comments/",
    "headers": {
        "Return-Path": "<libcamera-devel-bounces@lists.libcamera.org>",
        "X-Original-To": "parsemail@patchwork.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 6568BBF415\n\tfor <parsemail@patchwork.libcamera.org>;\n\tWed, 20 Oct 2021 10:42:21 +0000 (UTC)",
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        "From": "Umang Jain <umang.jain@ideasonboard.com>",
        "To": "libcamera-devel@lists.libcamera.org",
        "Date": "Wed, 20 Oct 2021 16:12:08 +0530",
        "Message-Id": "<20211020104212.121743-1-umang.jain@ideasonboard.com>",
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        "Content-Transfer-Encoding": "8bit",
        "Subject": "[libcamera-devel] [PATCH v5 0/4] Async Post Processor",
        "X-BeenThere": "libcamera-devel@lists.libcamera.org",
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        "Errors-To": "libcamera-devel-bounces@lists.libcamera.org",
        "Sender": "\"libcamera-devel\" <libcamera-devel-bounces@lists.libcamera.org>"
    },
    "content": "This is v5 for Async Post Processor based on top of recent HAL\nrefactoring \"android: Overhaul request completion handling\"\n\nThis series primarily introduces a Thread worker class along\nwith a queue, in which request for post-process of streams\nare queued and processed ansychronously. All the context information\nis carried inside Camera3RequestDescriptor.\n\nPatch 1/4 and 2/4 introduces a notification mechanism to know\nthat a post-processing request has been finished. These run\nsynchronously.\n\n3/4 introduces the asynchronous-nity along with post-processor's\nqueue. \n\n4/4 prevents a small window of race while setting the descriptor\nstatus_ (since status can be set from 2 threads now, main thread vs\npost_processor's thread)\n\nNo CTS regressions seen on nautilus with this series.\n\nSome open questions/discussions:\n- As flush/stop scenarios are kept out of scope of this series,\n  however, I have kept flush() implementation for PostProcessorWorker\n  class in this series. It isn't called but makes the patch complete to\n  me.\n\n- streamsProcessMutex_ currently guards only post-processing bits\n  while it comes to descriptor->buffers_. Should we access-control\n  all calls to descriptor->buffers_ with streamProcessMutex_ (I don't\n  think so) but there might be a race I haven't considered.\n\n- As seen by 2/4, CameraStream::process returns a value to fail-check.\n  PostProcessor::process() doesn't (rather it notifies via signal\n  mechanism). There might be a case where multiple streams require\n  post-processor, 1 one them gets queued sucessfully, other one fails,\n  returning error value from CameraStream::process(). How would we\n  handle this situation. There is \\todo: mark in 3/4 regarding this.\n\nLaurent Pinchart (1):\n  android: camera_device: Protect descriptor status_ with lock\n\nUmang Jain (3):\n  android: Notify post processing completion via a signal\n  android: post_processor: Drop return value for process()\n  android: post_processor: Make post processing async\n\n src/android/camera_device.cpp            | 143 +++++++++++++++++------\n src/android/camera_device.h              |  12 +-\n src/android/camera_request.h             |   8 ++\n src/android/camera_stream.cpp            | 122 +++++++++++++++++--\n src/android/camera_stream.h              |  38 +++++-\n src/android/jpeg/post_processor_jpeg.cpp |  14 +--\n src/android/jpeg/post_processor_jpeg.h   |   6 +-\n src/android/post_processor.h             |  15 ++-\n src/android/yuv/post_processor_yuv.cpp   |  20 ++--\n src/android/yuv/post_processor_yuv.h     |   6 +-\n 10 files changed, 312 insertions(+), 72 deletions(-)"
}