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{ "id": 27253, "url": "https://patchwork.libcamera.org/api/covers/27253/?format=api", "web_url": "https://patchwork.libcamera.org/cover/27253/", "project": { "id": 1, "url": "https://patchwork.libcamera.org/api/projects/1/?format=api", "name": "libcamera", "link_name": "libcamera", "list_id": "libcamera_core", "list_email": "libcamera-devel@lists.libcamera.org", "web_url": "", "scm_url": "", "webscm_url": "" }, "msgid": "<20260706222245.247396-1-bryan.odonoghue@linaro.org>", "date": "2026-07-06T22:22:39", "name": "[v6,0/6] libcamera: software_isp: gpu: Add go faster stripes", "submitter": { "id": 175, "url": "https://patchwork.libcamera.org/api/people/175/?format=api", "name": "Bryan O'Donoghue", "email": "bryan.odonoghue@linaro.org" }, "mbox": "https://patchwork.libcamera.org/cover/27253/mbox/", "series": [ { "id": 6042, "url": "https://patchwork.libcamera.org/api/series/6042/?format=api", "web_url": "https://patchwork.libcamera.org/project/libcamera/list/?series=6042", "date": "2026-07-06T22:22:39", "name": "libcamera: software_isp: gpu: Add go faster stripes", "version": 6, "mbox": "https://patchwork.libcamera.org/series/6042/mbox/" } ], "comments": "https://patchwork.libcamera.org/api/covers/27253/comments/", "headers": { "Return-Path": "<libcamera-devel-bounces@lists.libcamera.org>", "X-Original-To": "parsemail@patchwork.libcamera.org", "Delivered-To": "parsemail@patchwork.libcamera.org", "Received": [ "from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id 6D1CBC3308\n\tfor <parsemail@patchwork.libcamera.org>;\n\tMon, 6 Jul 2026 22:22:59 +0000 (UTC)", "from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 1B32E6605A;\n\tTue, 7 Jul 2026 00:22:58 +0200 (CEST)", "from mail-wr1-x42c.google.com (mail-wr1-x42c.google.com\n\t[IPv6:2a00:1450:4864:20::42c])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 7B85965FBE\n\tfor <libcamera-devel@lists.libcamera.org>;\n\tTue, 7 Jul 2026 00:22:56 +0200 (CEST)", "by mail-wr1-x42c.google.com with SMTP id\n\tffacd0b85a97d-47640541585so2175480f8f.1\n\tfor <libcamera-devel@lists.libcamera.org>;\n\tMon, 06 Jul 2026 15:22:56 -0700 (PDT)", "from inspiron14p-linux ([109.77.44.220])\n\tby smtp.gmail.com with ESMTPSA id\n\tffacd0b85a97d-47aa039ad21sm27916413f8f.20.2026.07.06.15.22.55\n\t(version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256);\n\tMon, 06 Jul 2026 15:22:55 -0700 (PDT)" ], "Authentication-Results": "lancelot.ideasonboard.com; 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\n\tMon, 06 Jul 2026 15:22:55 -0700 (PDT)", "From": "Bryan O'Donoghue <bryan.odonoghue@linaro.org>", "To": "libcamera-devel@lists.libcamera.org", "Cc": "bryan.odonoghue@linaro.org,\n\tpavel@ucw.cz", "Subject": "[PATCH v6 0/6] libcamera: software_isp: gpu: Add go faster stripes", "Date": "Mon, 6 Jul 2026 23:22:39 +0100", "Message-ID": "<20260706222245.247396-1-bryan.odonoghue@linaro.org>", "X-Mailer": "git-send-email 2.54.0", "MIME-Version": "1.0", "Content-Transfer-Encoding": "8bit", "X-BeenThere": "libcamera-devel@lists.libcamera.org", "X-Mailman-Version": "2.1.29", "Precedence": "list", "List-Id": "<libcamera-devel.lists.libcamera.org>", "List-Unsubscribe": "<https://lists.libcamera.org/options/libcamera-devel>,\n\t<mailto:libcamera-devel-request@lists.libcamera.org?subject=unsubscribe>", "List-Archive": "<https://lists.libcamera.org/pipermail/libcamera-devel/>", "List-Post": "<mailto:libcamera-devel@lists.libcamera.org>", "List-Help": "<mailto:libcamera-devel-request@lists.libcamera.org?subject=help>", "List-Subscribe": "<https://lists.libcamera.org/listinfo/libcamera-devel>,\n\t<mailto:libcamera-devel-request@lists.libcamera.org?subject=subscribe>", "Errors-To": "libcamera-devel-bounces@lists.libcamera.org", "Sender": "\"libcamera-devel\" <libcamera-devel-bounces@lists.libcamera.org>" }, "content": "v6:\n- Uses std::deque<std::pair<SharedFD, std::unique_ptr<eGLImage>>>; - Robert\n- Drops SharedFD patch - Robert\n\nLink: https://gitlab.freedesktop.org/camera/libcamera-softisp/-/pipelines/1700783\n\nv5:\n- use activateBindTexture in createTexture2D - Robert\n\nLink: https://gitlab.freedesktop.org/camera/libcamera-softisp/-/pipelines/1700395\n\nv4:\n- Sizes cache as indicated at configure\n- Ejects oldest entry on cache miss if cache is full. This allows an external\n application to keep feeding buffers in.\n- Reverts to using per image dma-buf flags - this is because again we can\n have heterogeneous sources of buffers.\n- Takes Barnabas' suggested SharedFD patch - Robert\n- Accumulates RB as indicated by Milan\n\nLink: https://gitlab.freedesktop.org/camera/libcamera-softisp/-/pipelines/1700354\n\nv3:\n- Fixes a missing switch default from libcamera ci loop - bod\n\nv2:\n- Reverts to debayer_egl specific caching mechanism - Laurent\n- Pivots on dmabuf handle as key for cache. dmabuf handle\n must be unique between start() and stop() for eglCreateImageKHR to work - Barnabas\n- Ensures sizeof cache doesn't exceed the number of expected buffers\n as discovered during configure() - Barnabas\n- Drops GL_16F patch - Robert\n- Drops the \"input\" name from createInputTexture2D() - Robert\n- Adds RB as specified by Robert\n\nv1:\nFollowing on from Robert Mader's ask to bring forward GPUISP multi-pass\ncache operations to mainline first, I've done some work to enable that.\n\nThis series implements an input/output texture caching scheme which results\nin an overall absolute 4.5 millisecond - roughly improvement in performance\nper processed frame. This is a bit of an odd result as I was expecting to\nshave a particular % off of each frame in the order of 20% or so. My best\nguess is that particular paths we are optimising here are around texture\ngeneration and these are \"fixed costs\" on the CPU side.\n\nOne very welcome outcome of this series is genuine zero-copy on dma-buf\npaths we can support it on i.e. on paths where the CSI2 and GPU strides\nagree.\n\nThe numbers cited in my example are for non dma-buf handle upload and\ndma-buf handle render-to-texture on the output so, in fact I'd expect to\nsee a much larger improvement on systems where dma-buf handle is used on\nboth paths.\n\nAs it is on my test reference systems I have a 50% improvement per frame\nfor one system, a 20% improvement on another system or we could view it as\na fixed 4.5 millisecond improvement on both.\n\nI implemented the cache around V4L2BufferCache as per Barnabas' suggestion,\nincluding a fixed cache size.\n\nBryan O'Donoghue (6):\n libcamera: software_isp: debayer_egl: Pass eglImage as parameter to\n setShaderVariables\n libcamera: egl: Add new helper attachTextureToFBO\n libcamera: egl: Add createOutputTexture2D\n libcamera: egl: Add activateBindTexture\n libcamera: egl: Add updateTexture2D\n libcamera: software_isp: debayer_egl: Implement input/output frame\n caching mechanism\n\n include/libcamera/internal/egl.h | 5 +\n src/libcamera/egl.cpp | 96 ++++++++++++---\n src/libcamera/software_isp/debayer_egl.cpp | 129 ++++++++++++++++-----\n src/libcamera/software_isp/debayer_egl.h | 13 ++-\n 4 files changed, 192 insertions(+), 51 deletions(-)" }