{"id":16083,"url":"https://patchwork.libcamera.org/api/1.1/patches/16083/?format=json","web_url":"https://patchwork.libcamera.org/patch/16083/","project":{"id":1,"url":"https://patchwork.libcamera.org/api/1.1/projects/1/?format=json","name":"libcamera","link_name":"libcamera","list_id":"libcamera_core","list_email":"libcamera-devel@lists.libcamera.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20220527144447.94891-12-tomi.valkeinen@ideasonboard.com>","date":"2022-05-27T14:44:28","name":"[libcamera-devel,v3,11/30] py: Add README.md","commit_ref":null,"pull_url":null,"state":"superseded","archived":false,"hash":"edca7fd1e5cb4692dcda652254e86b02005f0303","submitter":{"id":109,"url":"https://patchwork.libcamera.org/api/1.1/people/109/?format=json","name":"Tomi Valkeinen","email":"tomi.valkeinen@ideasonboard.com"},"delegate":null,"mbox":"https://patchwork.libcamera.org/patch/16083/mbox/","series":[{"id":3146,"url":"https://patchwork.libcamera.org/api/1.1/series/3146/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=3146","date":"2022-05-27T14:44:17","name":"More misc Python patches","version":3,"mbox":"https://patchwork.libcamera.org/series/3146/mbox/"}],"comments":"https://patchwork.libcamera.org/api/patches/16083/comments/","check":"pending","checks":"https://patchwork.libcamera.org/api/patches/16083/checks/","tags":{},"headers":{"Return-Path":"","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 7F1F4C326D\n\tfor ;\n\tFri, 27 May 2022 14:45:24 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 1543A6564A;\n\tFri, 27 May 2022 16:45:24 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 3B89065634\n\tfor ;\n\tFri, 27 May 2022 16:45:10 +0200 (CEST)","from deskari.lan (91-156-85-209.elisa-laajakaista.fi\n\t[91.156.85.209])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id A52B71248;\n\tFri, 27 May 2022 16:45:09 +0200 (CEST)"],"DKIM-Signature":["v=1; a=rsa-sha256; c=relaxed/simple; d=libcamera.org;\n\ts=mail; t=1653662724;\n\tbh=k7Le+XS6rpj2VkjjYXVlhnP5FKg9Q20/vIYaMFUH6WQ=;\n\th=To:Date:In-Reply-To:References:Subject:List-Id:List-Unsubscribe:\n\tList-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:\n\tFrom;\n\tb=qxRljEObcG5aJ9Dyrlw8g4Am0LsjjYfdHxakYgxisyXn8mVdElQLu9roNyq/1zB1i\n\ttmA857P1I5paz9mOjbxD41yr5KOO5m7kmhYK7wFPu8rf7VVrLf4r4mxhyNJWSsHTXH\n\t7bURZVNKhPB23h7nBMmAJZMWT+Vm45RKfRf3PSPpXt9TjoCM7FaT7VM1RMEb3PhOak\n\tMgq0kDN26Zt3RUsm1bN4bbrr3g2N50DRrqzuHoM+F8goQ35KEyypjC9wVrs4OX3QIV\n\tw3JYEerI2NqBEEJX9GpCHwFAkffKR0IedcbqIthmh36NDZpzPJhOSRu+3daVbhnR+E\n\tcGUQtaBZllASg==","v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1653662710;\n\tbh=k7Le+XS6rpj2VkjjYXVlhnP5FKg9Q20/vIYaMFUH6WQ=;\n\th=From:To:Cc:Subject:Date:In-Reply-To:References:From;\n\tb=pXwr1K4UQ344VM2zKDggc9+7X6MKQR69tvfHVCY5uWoah/72JAJ2YBCgAu59fProu\n\tVYvJGcZ1D+oUIOQYAQvFjoaebyRsRWN4gSwrdvd69gWAe6ElIfkBnx705IPBG9KSDe\n\tYHAuJvQ9DDAB9DRs+oco8XarF+t5NKqpNsH2K+sY="],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key; \n\tunprotected) header.d=ideasonboard.com\n\theader.i=@ideasonboard.com\n\theader.b=\"pXwr1K4U\"; dkim-atps=neutral","To":"libcamera-devel@lists.libcamera.org,\n\tDavid Plowman ,\n\tKieran Bingham ,\n\tLaurent Pinchart ,\n\tJacopo Mondi ","Date":"Fri, 27 May 2022 17:44:28 +0300","Message-Id":"<20220527144447.94891-12-tomi.valkeinen@ideasonboard.com>","X-Mailer":"git-send-email 2.34.1","In-Reply-To":"<20220527144447.94891-1-tomi.valkeinen@ideasonboard.com>","References":"<20220527144447.94891-1-tomi.valkeinen@ideasonboard.com>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","Subject":"[libcamera-devel] [PATCH v3 11/30] py: Add README.md","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","From":"Tomi Valkeinen via libcamera-devel\n\t","Reply-To":"Tomi Valkeinen ","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "},"content":"Add a basic README for the Python bindings. While not a proper doc, the\nREADME and the examples should give enough guidance for users who are\nsomewhat familiar with libcamera.\n\nSigned-off-by: Tomi Valkeinen \nReviewed-by: Laurent Pinchart \n---\n src/py/README.md | 60 ++++++++++++++++++++++++++++++++++++++++++++++++\n 1 file changed, 60 insertions(+)\n create mode 100644 src/py/README.md","diff":"diff --git a/src/py/README.md b/src/py/README.md\nnew file mode 100644\nindex 00000000..74a8cd9f\n--- /dev/null\n+++ b/src/py/README.md\n@@ -0,0 +1,60 @@\n+# Python Bindings for libcamera\n+\n+*WARNING* The bindings are under work, and the API will change.\n+\n+## Differences to the C++ API\n+\n+As a rule of thumb the bindings try to follow the C++ API when possible. This\n+chapter lists the differences.\n+\n+Mostly these differences fall under two categories:\n+\n+1. Differences caused by the inherent differences between C++ and Python.\n+These differences are usually caused by the use of threads or differences in\n+C++ vs Python memory management.\n+\n+2. Differences caused by the code being work-in-progress. It's not always\n+trivial to create a binding in a satisfying way, and the current bindings\n+contain simplified versions of the C++ API just to get forward. These\n+differences are expected to eventually go away.\n+\n+### Coding Style\n+\n+The C++ code for the bindings follows the libcamera coding style as much as\n+possible. Note that the indentation does not quite follow the clang-format\n+style, as clang-format makes a mess of the style used.\n+\n+The API visible to the Python side follows the Python style as much as possible.\n+\n+This means that e.g. `Camera::generateConfiguration` maps to\n+`Camera.generate_configuration`.\n+\n+### CameraManager\n+\n+The Python API provides a singleton CameraManager via `CameraManager.singleton()`.\n+There is no need to start or stop the CameraManager.\n+\n+### Handling Completed Requests\n+\n+The Python bindings do not expose the Camera::requestCompleted signal\n+directly as the signal is invoked from another thread and it has real-time\n+constraints. Instead the bindings will internally queue the completed\n+requests and use an eventfd to inform the user that there are completed\n+requests.\n+\n+The user can wait on the eventfd, and upon getting an event, use\n+CameraManager.read_event() to clear the eventfd event and\n+CameraManager.get_ready_requests() to get the completed requests.\n+\n+### Controls & Properties\n+\n+The classes related to controls and properties are rather complex to implement\n+directly in the Python bindings. There are some simplifications on the Python\n+bindings:\n+\n+- There is no ControlValue class. Python objects are automatically converted\n+ to ControlValues and vice versa.\n+- There is no ControlList class. A python dict with ControlId keys and python\n+ object values is used instead.\n+- There is no ControlInfoMap class. A python dict with ControlId keys and\n+ ControlInfo values is used instead.\n","prefixes":["libcamera-devel","v3","11/30"]}