[{"id":30861,"web_url":"https://patchwork.libcamera.org/comment/30861/","msgid":"<20240819211534.GA4770@pendragon.ideasonboard.com>","date":"2024-08-19T21:15:34","subject":"Re: [PATCH v3 3/7] Documentation: Synchronise camera stack details","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/people/2/","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"content":"Hi Dan,\n\nThank you for the patch.\n\nOn Mon, Aug 19, 2024 at 05:09:17PM +0100, Daniel Scally wrote:\n> There are two near-duplicate instances of the camera stack details\n> in the Documentation, in docs.rst and guides/introduction.rst. Remove\n> them from guides/introduction.rst, with the exception of the\n> explanations of the V4L2 Compatibility Layer and the Android HAL\n> which are moved to the Camera Stack section in docs.rst. The Docs\n> page already had its own separate version of those details but they\n> are distinct and seemingly out of date - remove them.\n> \n> Signed-off-by: Daniel Scally \n> ---\n> Changes since v2:\n> \n> \t- Refocused this patch to focus on camera stack section instead of the\n> \t libcamera architecture section. Dropped the R-b.\n> \n> Changes since v1:\n> \n> \t- None\n> \n> \n> Documentation/docs.rst | 56 +++++++------\n> Documentation/guides/introduction.rst | 109 +-------------------------\n> 2 files changed, 31 insertions(+), 134 deletions(-)\n> \n> diff --git a/Documentation/docs.rst b/Documentation/docs.rst\n> index 5871961c..0eacc924 100644\n> --- a/Documentation/docs.rst\n> +++ b/Documentation/docs.rst\n> @@ -239,6 +239,36 @@ The camera stack comprises four software layers. From bottom to top:\n> libcamera framework or libcamera adaptation, and are outside of\n> the scope of the libcamera project.\n> \n> +V4L2 Compatibility Layer\n> + V4L2 compatibility is achieved through a shared library that traps all\n> + accesses to camera devices and routes them to libcamera to emulate high-level\n> + V4L2 camera devices. It is injected in a process address space through\n> + ``LD_PRELOAD`` and is completely transparent for applications.\n> +\n> + The compatibility layer exposes camera device features on a best-effort basis,\n> + and aims for the level of features traditionally available from a UVC camera\n> + designed for video conferencing.\n> +\n> +Android Camera HAL\n> + Camera support for Android is achieved through a generic Android camera HAL\n> + implementation on top of libcamera. The HAL implements features required by\n> + Android and out of scope from libcamera, such as JPEG encoding support.\n> +\n> + This component is used to provide support for ChromeOS platforms\n\ns/$/./\n\n> +\n> +GStreamer element (gstlibcamerasrc)\n> + A `GStreamer element`_ is provided to allow capture from libcamera supported\n> + devices through GStreamer pipelines, and connect to other elements for further\n> + processing.\n> +\n> + Development of this element is ongoing and is limited to a single stream.\n\nThis isn't true anymore, we now support multiple streams. This can be\naddressed in a separate patch, it's easier to review refactorings\nseparately from documentation updates.\n\nReviewed-by: Laurent Pinchart \n\n> +\n> +Native libcamera API\n> + Applications can make use of the libcamera API directly using the C++\n> + API. An example application and walkthrough using the libcamera API can be\n> + followed in the :doc:`Application writer's guide `\n> +\n> +.. _GStreamer element: https://gstreamer.freedesktop.org/documentation/application-development/basics/elements.html\n> \n> libcamera Architecture\n> ======================\n> @@ -374,29 +404,3 @@ Helpers and Support Classes\n> self-contained support classes, even if such code is present only once in the\n> code base, in order to keep the source code clean and easy to read. This\n> should be the case for instance for plugin management.\n> -\n> -\n> -V4L2 Compatibility Layer\n> -------------------------\n> -\n> -V4L2 compatibility is achieved through a shared library that traps all\n> -accesses to camera devices and routes them to libcamera to emulate high-level\n> -V4L2 camera devices. It is injected in a process address space through\n> -`LD_PRELOAD` and is completely transparent for applications.\n> -\n> -The compatibility layer exposes camera device features on a best-effort basis,\n> -and aims for the level of features traditionally available from a UVC camera\n> -designed for video conferencing.\n> -\n> -\n> -Android Camera HAL\n> -------------------\n> -\n> -Camera support for Android is achieved through a generic Android\n> -camera HAL implementation on top of libcamera. The HAL will implement internally\n> -features required by Android and missing from libcamera, such as JPEG encoding\n> -support.\n> -\n> -The Android camera HAL implementation will initially target the\n> -LIMITED hardware level, with support for the FULL level then being gradually\n> -implemented.\n> diff --git a/Documentation/guides/introduction.rst b/Documentation/guides/introduction.rst\n> index 8368bd4a..d1e67654 100644\n> --- a/Documentation/guides/introduction.rst\n> +++ b/Documentation/guides/introduction.rst\n> @@ -26,8 +26,7 @@ desirable results from the camera.\n> .. _Media Controller: https://www.linuxtv.org/downloads/v4l-dvb-apis-new/userspace-api/mediactl/media-controller.html\n> \n> \n> -In this developers guide, we will explore the `Camera Stack`_ and how it is\n> -can be visualised at a high level, and explore the internal `Architecture`_ of\n> +In this developers guide, we will explore the internal `Architecture`_ of\n> the libcamera library with its components. The current `Platform Support`_ is\n> detailed, as well as an overview of the `Licensing`_ requirements of the\n> project.\n> @@ -42,112 +41,6 @@ provides a tutorial of the key APIs exposed by libcamera.\n> \n> .. TODO: Correctly link to the other articles of the guide\n> \n> -Camera Stack\n> -------------\n> -\n> -The libcamera library is implemented in userspace, and makes use of underlying\n> -kernel drivers that directly interact with hardware.\n> -\n> -Applications can make use of libcamera through the native `libcamera API`_'s or\n> -through an adaptation layer integrating libcamera into a larger framework.\n> -\n> -.. _libcamera API: https://www.libcamera.org/api-html/index.html\n> -\n> -::\n> -\n> - Application Layer\n> - / +--------------+ +--------------+ +--------------+ +--------------+\n> - | | Native | | Framework | | Native | | Android |\n> - | | V4L2 | | Application | | libcamera | | Camera |\n> - | | Application | | (gstreamer) | | Application | | Framework |\n> - \\ +--------------+ +--------------+ +--------------+ +--------------+\n> -\n> - ^ ^ ^ ^\n> - | | | |\n> - | | | |\n> - v v | v\n> - Adaptation Layer |\n> - / +--------------+ +--------------+ | +--------------+\n> - | | V4L2 | | gstreamer | | | Android |\n> - | | Compatibility| | element | | | Camera |\n> - | | (preload) | |(libcamerasrc)| | | HAL |\n> - \\ +--------------+ +--------------+ | +--------------+\n> - |\n> - ^ ^ | ^\n> - | | | |\n> - | | | |\n> - v v v v\n> - libcamera Framework\n> - / +--------------------------------------------------------------------+\n> - | | |\n> - | | libcamera |\n> - | | |\n> - \\ +--------------------------------------------------------------------+\n> -\n> - ^ ^ ^\n> - Userspace | | |\n> - --------------------- | ---------------- | ---------------- | ---------------\n> - Kernel | | |\n> - v v v\n> -\n> - +-----------+ +-----------+ +-----------+\n> - | Media | <--> | Video | <--> | V4L2 |\n> - | Device | | Device | | Subdev |\n> - +-----------+ +-----------+ +-----------+\n> -\n> -The camera stack comprises of four software layers. From bottom to top:\n> -\n> -* The kernel drivers control the camera hardware and expose a low-level\n> - interface to userspace through the Linux kernel V4L2 family of APIs\n> - (Media Controller API, V4L2 Video Device API and V4L2 Subdev API).\n> -\n> -* The libcamera framework is the core part of the stack. It handles all control\n> - of the camera devices in its core component, libcamera, and exposes a native\n> - C++ API to upper layers.\n> -\n> -* The libcamera adaptation layer is an umbrella term designating the components\n> - that interface to libcamera in other frameworks. Notable examples are the V4L2\n> - compatibility layer, the gstreamer libcamera element, and the Android camera\n> - HAL implementation based on libcamera which are provided as a part of the\n> - libcamera project.\n> -\n> -* The applications and upper level frameworks are based on the libcamera\n> - framework or libcamera adaptation, and are outside of the scope of the\n> - libcamera project, however example native applications (cam, qcam) are\n> - provided for testing.\n> -\n> -\n> -V4L2 Compatibility Layer\n> - V4L2 compatibility is achieved through a shared library that traps all\n> - accesses to camera devices and routes them to libcamera to emulate high-level\n> - V4L2 camera devices. It is injected in a process address space through\n> - ``LD_PRELOAD`` and is completely transparent for applications.\n> -\n> - The compatibility layer exposes camera device features on a best-effort basis,\n> - and aims for the level of features traditionally available from a UVC camera\n> - designed for video conferencing.\n> -\n> -Android Camera HAL\n> - Camera support for Android is achieved through a generic Android camera HAL\n> - implementation on top of libcamera. The HAL implements features required by\n> - Android and out of scope from libcamera, such as JPEG encoding support.\n> -\n> - This component is used to provide support for ChromeOS platforms\n> -\n> -GStreamer element (gstlibcamerasrc)\n> - A `GStreamer element`_ is provided to allow capture from libcamera supported\n> - devices through GStreamer pipelines, and connect to other elements for further\n> - processing.\n> -\n> - Development of this element is ongoing and is limited to a single stream.\n> -\n> -Native libcamera API\n> - Applications can make use of the libcamera API directly using the C++\n> - API. An example application and walkthrough using the libcamera API can be\n> - followed in the `Application Writers Guide`_\n> -\n> -.. _GStreamer element: https://gstreamer.freedesktop.org/documentation/application-development/basics/elements.html\n> -\n> Architecture\n> ------------\n>","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 09817C323E\n\tfor ;\n\tMon, 19 Aug 2024 21:16:04 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 446B0633B4;\n\tMon, 19 Aug 2024 23:16:03 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 98CB3633B3\n\tfor ;\n\tMon, 19 Aug 2024 23:16:01 +0200 (CEST)","from pendragon.ideasonboard.com (81-175-209-231.bb.dnainternet.fi\n\t[81.175.209.231])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id D01605B3;\n\tMon, 19 Aug 2024 23:14:59 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"Xjy22dJa\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1724102100;\n\tbh=utS269PMWxnDaFSm0t9zIHqntxsxidN6auEoURxt4rc=;\n\th=Date:From:To:Cc:Subject:References:In-Reply-To:From;\n\tb=Xjy22dJaLXo5cr88X10iH77/I+Vr+eA3MobwdDkwZck7amt8lcw7jO5dN2Dakj61V\n\t7CT2FeZ7QnT877bYd0eQ85pvRNXZL6SJgxjR5XWSnxhPk4TZKc5XKUsLKZSHSTZG2I\n\tRhS9SGzMGHF8ata8wVFKh/yHF4kmDAmCGax95puQ=","Date":"Tue, 20 Aug 2024 00:15:34 +0300","From":"Laurent Pinchart ","To":"Daniel Scally ","Cc":"libcamera-devel@lists.libcamera.org","Subject":"Re: [PATCH v3 3/7] Documentation: Synchronise camera stack details","Message-ID":"<20240819211534.GA4770@pendragon.ideasonboard.com>","References":"<20240819160921.468981-1-dan.scally@ideasonboard.com>\n\t<20240819160921.468981-4-dan.scally@ideasonboard.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=utf-8","Content-Disposition":"inline","In-Reply-To":"<20240819160921.468981-4-dan.scally@ideasonboard.com>","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","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "}},{"id":30865,"web_url":"https://patchwork.libcamera.org/comment/30865/","msgid":"<70a0f847-3ca7-4e9c-82f9-e4829e45377a@ideasonboard.com>","date":"2024-08-20T07:27:49","subject":"Re: [PATCH v3 3/7] Documentation: Synchronise camera stack details","submitter":{"id":156,"url":"https://patchwork.libcamera.org/api/people/156/","name":"Dan Scally","email":"dan.scally@ideasonboard.com"},"content":"Hi Laurent\n\nOn 19/08/2024 22:15, Laurent Pinchart wrote:\n> Hi Dan,\n>\n> Thank you for the patch.\n>\n> On Mon, Aug 19, 2024 at 05:09:17PM +0100, Daniel Scally wrote:\n>> There are two near-duplicate instances of the camera stack details\n>> in the Documentation, in docs.rst and guides/introduction.rst. Remove\n>> them from guides/introduction.rst, with the exception of the\n>> explanations of the V4L2 Compatibility Layer and the Android HAL\n>> which are moved to the Camera Stack section in docs.rst. The Docs\n>> page already had its own separate version of those details but they\n>> are distinct and seemingly out of date - remove them.\n>>\n>> Signed-off-by: Daniel Scally \n>> ---\n>> Changes since v2:\n>>\n>> \t- Refocused this patch to focus on camera stack section instead of the\n>> \t libcamera architecture section. Dropped the R-b.\n>>\n>> Changes since v1:\n>>\n>> \t- None\n>>\n>>\n>> Documentation/docs.rst | 56 +++++++------\n>> Documentation/guides/introduction.rst | 109 +-------------------------\n>> 2 files changed, 31 insertions(+), 134 deletions(-)\n>>\n>> diff --git a/Documentation/docs.rst b/Documentation/docs.rst\n>> index 5871961c..0eacc924 100644\n>> --- a/Documentation/docs.rst\n>> +++ b/Documentation/docs.rst\n>> @@ -239,6 +239,36 @@ The camera stack comprises four software layers. From bottom to top:\n>> libcamera framework or libcamera adaptation, and are outside of\n>> the scope of the libcamera project.\n>> \n>> +V4L2 Compatibility Layer\n>> + V4L2 compatibility is achieved through a shared library that traps all\n>> + accesses to camera devices and routes them to libcamera to emulate high-level\n>> + V4L2 camera devices. It is injected in a process address space through\n>> + ``LD_PRELOAD`` and is completely transparent for applications.\n>> +\n>> + The compatibility layer exposes camera device features on a best-effort basis,\n>> + and aims for the level of features traditionally available from a UVC camera\n>> + designed for video conferencing.\n>> +\n>> +Android Camera HAL\n>> + Camera support for Android is achieved through a generic Android camera HAL\n>> + implementation on top of libcamera. The HAL implements features required by\n>> + Android and out of scope from libcamera, such as JPEG encoding support.\n>> +\n>> + This component is used to provide support for ChromeOS platforms\n> s/$/./\n>\n>> +\n>> +GStreamer element (gstlibcamerasrc)\n>> + A `GStreamer element`_ is provided to allow capture from libcamera supported\n>> + devices through GStreamer pipelines, and connect to other elements for further\n>> + processing.\n>> +\n>> + Development of this element is ongoing and is limited to a single stream.\n> This isn't true anymore, we now support multiple streams. This can be\n> addressed in a separate patch, it's easier to review refactorings\n> separately from documentation updates.\n\n\nIs the rest of the sentence worth retaining? Is the GStreamer element still under active development?\n\n>\n> Reviewed-by: Laurent Pinchart \n>\n>> +\n>> +Native libcamera API\n>> + Applications can make use of the libcamera API directly using the C++\n>> + API. An example application and walkthrough using the libcamera API can be\n>> + followed in the :doc:`Application writer's guide `\n>> +\n>> +.. _GStreamer element: https://gstreamer.freedesktop.org/documentation/application-development/basics/elements.html\n>> \n>> libcamera Architecture\n>> ======================\n>> @@ -374,29 +404,3 @@ Helpers and Support Classes\n>> self-contained support classes, even if such code is present only once in the\n>> code base, in order to keep the source code clean and easy to read. This\n>> should be the case for instance for plugin management.\n>> -\n>> -\n>> -V4L2 Compatibility Layer\n>> -------------------------\n>> -\n>> -V4L2 compatibility is achieved through a shared library that traps all\n>> -accesses to camera devices and routes them to libcamera to emulate high-level\n>> -V4L2 camera devices. It is injected in a process address space through\n>> -`LD_PRELOAD` and is completely transparent for applications.\n>> -\n>> -The compatibility layer exposes camera device features on a best-effort basis,\n>> -and aims for the level of features traditionally available from a UVC camera\n>> -designed for video conferencing.\n>> -\n>> -\n>> -Android Camera HAL\n>> -------------------\n>> -\n>> -Camera support for Android is achieved through a generic Android\n>> -camera HAL implementation on top of libcamera. The HAL will implement internally\n>> -features required by Android and missing from libcamera, such as JPEG encoding\n>> -support.\n>> -\n>> -The Android camera HAL implementation will initially target the\n>> -LIMITED hardware level, with support for the FULL level then being gradually\n>> -implemented.\n>> diff --git a/Documentation/guides/introduction.rst b/Documentation/guides/introduction.rst\n>> index 8368bd4a..d1e67654 100644\n>> --- a/Documentation/guides/introduction.rst\n>> +++ b/Documentation/guides/introduction.rst\n>> @@ -26,8 +26,7 @@ desirable results from the camera.\n>> .. _Media Controller: https://www.linuxtv.org/downloads/v4l-dvb-apis-new/userspace-api/mediactl/media-controller.html\n>> \n>> \n>> -In this developers guide, we will explore the `Camera Stack`_ and how it is\n>> -can be visualised at a high level, and explore the internal `Architecture`_ of\n>> +In this developers guide, we will explore the internal `Architecture`_ of\n>> the libcamera library with its components. The current `Platform Support`_ is\n>> detailed, as well as an overview of the `Licensing`_ requirements of the\n>> project.\n>> @@ -42,112 +41,6 @@ provides a tutorial of the key APIs exposed by libcamera.\n>> \n>> .. TODO: Correctly link to the other articles of the guide\n>> \n>> -Camera Stack\n>> -------------\n>> -\n>> -The libcamera library is implemented in userspace, and makes use of underlying\n>> -kernel drivers that directly interact with hardware.\n>> -\n>> -Applications can make use of libcamera through the native `libcamera API`_'s or\n>> -through an adaptation layer integrating libcamera into a larger framework.\n>> -\n>> -.. _libcamera API: https://www.libcamera.org/api-html/index.html\n>> -\n>> -::\n>> -\n>> - Application Layer\n>> - / +--------------+ +--------------+ +--------------+ +--------------+\n>> - | | Native | | Framework | | Native | | Android |\n>> - | | V4L2 | | Application | | libcamera | | Camera |\n>> - | | Application | | (gstreamer) | | Application | | Framework |\n>> - \\ +--------------+ +--------------+ +--------------+ +--------------+\n>> -\n>> - ^ ^ ^ ^\n>> - | | | |\n>> - | | | |\n>> - v v | v\n>> - Adaptation Layer |\n>> - / +--------------+ +--------------+ | +--------------+\n>> - | | V4L2 | | gstreamer | | | Android |\n>> - | | Compatibility| | element | | | Camera |\n>> - | | (preload) | |(libcamerasrc)| | | HAL |\n>> - \\ +--------------+ +--------------+ | +--------------+\n>> - |\n>> - ^ ^ | ^\n>> - | | | |\n>> - | | | |\n>> - v v v v\n>> - libcamera Framework\n>> - / +--------------------------------------------------------------------+\n>> - | | |\n>> - | | libcamera |\n>> - | | |\n>> - \\ +--------------------------------------------------------------------+\n>> -\n>> - ^ ^ ^\n>> - Userspace | | |\n>> - --------------------- | ---------------- | ---------------- | ---------------\n>> - Kernel | | |\n>> - v v v\n>> -\n>> - +-----------+ +-----------+ +-----------+\n>> - | Media | <--> | Video | <--> | V4L2 |\n>> - | Device | | Device | | Subdev |\n>> - +-----------+ +-----------+ +-----------+\n>> -\n>> -The camera stack comprises of four software layers. From bottom to top:\n>> -\n>> -* The kernel drivers control the camera hardware and expose a low-level\n>> - interface to userspace through the Linux kernel V4L2 family of APIs\n>> - (Media Controller API, V4L2 Video Device API and V4L2 Subdev API).\n>> -\n>> -* The libcamera framework is the core part of the stack. It handles all control\n>> - of the camera devices in its core component, libcamera, and exposes a native\n>> - C++ API to upper layers.\n>> -\n>> -* The libcamera adaptation layer is an umbrella term designating the components\n>> - that interface to libcamera in other frameworks. Notable examples are the V4L2\n>> - compatibility layer, the gstreamer libcamera element, and the Android camera\n>> - HAL implementation based on libcamera which are provided as a part of the\n>> - libcamera project.\n>> -\n>> -* The applications and upper level frameworks are based on the libcamera\n>> - framework or libcamera adaptation, and are outside of the scope of the\n>> - libcamera project, however example native applications (cam, qcam) are\n>> - provided for testing.\n>> -\n>> -\n>> -V4L2 Compatibility Layer\n>> - V4L2 compatibility is achieved through a shared library that traps all\n>> - accesses to camera devices and routes them to libcamera to emulate high-level\n>> - V4L2 camera devices. It is injected in a process address space through\n>> - ``LD_PRELOAD`` and is completely transparent for applications.\n>> -\n>> - The compatibility layer exposes camera device features on a best-effort basis,\n>> - and aims for the level of features traditionally available from a UVC camera\n>> - designed for video conferencing.\n>> -\n>> -Android Camera HAL\n>> - Camera support for Android is achieved through a generic Android camera HAL\n>> - implementation on top of libcamera. The HAL implements features required by\n>> - Android and out of scope from libcamera, such as JPEG encoding support.\n>> -\n>> - This component is used to provide support for ChromeOS platforms\n>> -\n>> -GStreamer element (gstlibcamerasrc)\n>> - A `GStreamer element`_ is provided to allow capture from libcamera supported\n>> - devices through GStreamer pipelines, and connect to other elements for further\n>> - processing.\n>> -\n>> - Development of this element is ongoing and is limited to a single stream.\n>> -\n>> -Native libcamera API\n>> - Applications can make use of the libcamera API directly using the C++\n>> - API. An example application and walkthrough using the libcamera API can be\n>> - followed in the `Application Writers Guide`_\n>> -\n>> -.. _GStreamer element: https://gstreamer.freedesktop.org/documentation/application-development/basics/elements.html\n>> -\n>> Architecture\n>> ------------\n>>","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 928C4C323E\n\tfor ;\n\tTue, 20 Aug 2024 07:27:56 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 6E830633CE;\n\tTue, 20 Aug 2024 09:27:55 +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 EA43763369\n\tfor ;\n\tTue, 20 Aug 2024 09:27:52 +0200 (CEST)","from [192.168.0.43]\n\t(cpc141996-chfd3-2-0-cust928.12-3.cable.virginm.net [86.13.91.161])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id F2814581;\n\tTue, 20 Aug 2024 09:26:50 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"XkPffpbj\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1724138811;\n\tbh=2Suufn0kZZpJVNdc3dNvl2i0MOyrIfTZcTGQULPtTUY=;\n\th=Date:Subject:To:Cc:References:From:In-Reply-To:From;\n\tb=XkPffpbjEAhyI8rfiN8ZiCpZianRhDjUMZxUBBtm+8f62114ZWRwmtjxyJIE4uAy9\n\ttJkHUo6Vfhx0hlvZ8tDTmlV7xRVwBKX4/fUKtO6XBTgQvo3bgzcEXZHDWn5dhHEsLL\n\thtfhUkh3y/J7EKFb8FkiNgAlQA58z9vj2RsAZrK8=","Message-ID":"<70a0f847-3ca7-4e9c-82f9-e4829e45377a@ideasonboard.com>","Date":"Tue, 20 Aug 2024 08:27:49 +0100","MIME-Version":"1.0","User-Agent":"Mozilla Thunderbird","Subject":"Re: [PATCH v3 3/7] Documentation: Synchronise camera stack details","To":"Laurent Pinchart ","Cc":"libcamera-devel@lists.libcamera.org","References":"<20240819160921.468981-1-dan.scally@ideasonboard.com>\n\t<20240819160921.468981-4-dan.scally@ideasonboard.com>\n\t<20240819211534.GA4770@pendragon.ideasonboard.com>","Content-Language":"en-US","From":"Dan Scally ","Autocrypt":"addr=dan.scally@ideasonboard.com; keydata=\n\txsFNBGLydlEBEADa5O2s0AbUguprfvXOQun/0a8y2Vk6BqkQALgeD6KnXSWwaoCULp18etYW\n\tB31bfgrdphXQ5kUQibB0ADK8DERB4wrzrUb5CMxLBFE7mQty+v5NsP0OFNK9XTaAOcmD+Ove\n\teIjYvqurAaro91jrRVrS1gBRxIFqyPgNvwwL+alMZhn3/2jU2uvBmuRrgnc/e9cHKiuT3Dtq\n\tMHGPKL2m+plk+7tjMoQFfexoQ1JKugHAjxAhJfrkXh6uS6rc01bYCyo7ybzg53m1HLFJdNGX\n\tsUKR+dQpBs3SY4s66tc1sREJqdYyTsSZf80HjIeJjU/hRunRo4NjRIJwhvnK1GyjOvvuCKVU\n\tRWpY8dNjNu5OeAfdrlvFJOxIE9M8JuYCQTMULqd1NuzbpFMjc9524U3Cngs589T7qUMPb1H1\n\tNTA81LmtJ6Y+IV5/kiTUANflpzBwhu18Ok7kGyCq2a2jsOcVmk8gZNs04gyjuj8JziYwwLbf\n\tvzABwpFVcS8aR+nHIZV1HtOzyw8CsL8OySc3K9y+Y0NRpziMRvutrppzgyMb9V+N31mK9Mxl\n\t1YkgaTl4ciNWpdfUe0yxH03OCuHi3922qhPLF4XX5LN+NaVw5Xz2o3eeWklXdouxwV7QlN33\n\tu4+u2FWzKxDqO6WLQGjxPE0mVB4Gh5Pa1Vb0ct9Ctg0qElvtGQARAQABzShEYW4gU2NhbGx5\n\tIDxkYW4uc2NhbGx5QGlkZWFzb25ib2FyZC5jb20+wsGNBBMBCAA3FiEEsdtt8OWP7+8SNfQe\n\tkiQuh/L+GMQFAmLydlIFCQWjmoACGwMECwkIBwUVCAkKCwUWAgMBAAAKCRCSJC6H8v4YxDI2\n\tEAC2Gz0iyaXJkPInyshrREEWbo0CA6v5KKf3I/HlMPqkZ48bmGoYm4mEQGFWZJAT3K4ir8bg\n\tcEfs9V54gpbrZvdwS4abXbUK4WjKwEs8HK3XJv1WXUN2bsz5oEJWZUImh9gD3naiLLI9QMMm\n\tw/aZkT+NbN5/2KvChRWhdcha7+2Te4foOY66nIM+pw2FZM6zIkInLLUik2zXOhaZtqdeJZQi\n\tHSPU9xu7TRYN4cvdZAnSpG7gQqmLm5/uGZN1/sB3kHTustQtSXKMaIcD/DMNI3JN/t+RJVS7\n\tc0Jh/ThzTmhHyhxx3DRnDIy7kwMI4CFvmhkVC2uNs9kWsj1DuX5kt8513mvfw2OcX9UnNKmZ\n\tnhNCuF6DxVrL8wjOPuIpiEj3V+K7DFF1Cxw1/yrLs8dYdYh8T8vCY2CHBMsqpESROnTazboh\n\tAiQ2xMN1cyXtX11Qwqm5U3sykpLbx2BcmUUUEAKNsM//Zn81QXKG8vOx0ZdMfnzsCaCzt8f6\n\t9dcDBBI3tJ0BI9ByiocqUoL6759LM8qm18x3FYlxvuOs4wSGPfRVaA4yh0pgI+ModVC2Pu3y\n\tejE/IxeatGqJHh6Y+iJzskdi27uFkRixl7YJZvPJAbEn7kzSi98u/5ReEA8Qhc8KO/B7wprj\n\txjNMZNYd0Eth8+WkixHYj752NT5qshKJXcyUU87BTQRi8nZSARAAx0BJayh1Fhwbf4zoY56x\n\txHEpT6DwdTAYAetd3yiKClLVJadYxOpuqyWa1bdfQWPb+h4MeXbWw/53PBgn7gI2EA7ebIRC\n\tPJJhAIkeym7hHZoxqDQTGDJjxFEL11qF+U3rhWiL2Zt0Pl+zFq0eWYYVNiXjsIS4FI2+4m16\n\ttPbDWZFJnSZ828VGtRDQdhXfx3zyVX21lVx1bX4/OZvIET7sVUufkE4hrbqrrufre7wsjD1t\n\t8MQKSapVrr1RltpzPpScdoxknOSBRwOvpp57pJJe5A0L7+WxJ+vQoQXj0j+5tmIWOAV1qBQp\n\thyoyUk9JpPfntk2EKnZHWaApFp5TcL6c5LhUvV7F6XwOjGPuGlZQCWXee9dr7zym8iR3irWT\n\t+49bIh5PMlqSLXJDYbuyFQHFxoiNdVvvf7etvGfqFYVMPVjipqfEQ38ST2nkzx+KBICz7uwj\n\tJwLBdTXzGFKHQNckGMl7F5QdO/35An/QcxBnHVMXqaSd12tkJmoRVWduwuuoFfkTY5mUV3uX\n\txGj3iVCK4V+ezOYA7c2YolfRCNMTza6vcK/P4tDjjsyBBZrCCzhBvd4VVsnnlZhVaIxoky4K\n\taL+AP+zcQrUZmXmgZjXOLryGnsaeoVrIFyrU6ly90s1y3KLoPsDaTBMtnOdwxPmo1xisH8oL\n\ta/VRgpFBfojLPxMAEQEAAcLBfAQYAQgAJhYhBLHbbfDlj+/vEjX0HpIkLofy/hjEBQJi8nZT\n\tBQkFo5qAAhsMAAoJEJIkLofy/hjEXPcQAMIPNqiWiz/HKu9W4QIf1OMUpKn3YkVIj3p3gvfM\n\tRes4fGX94Ji599uLNrPoxKyaytC4R6BTxVriTJjWK8mbo9jZIRM4vkwkZZ2bu98EweSucxbp\n\tvjESsvMXGgxniqV/RQ/3T7LABYRoIUutARYq58p5HwSP0frF0fdFHYdTa2g7MYZl1ur2JzOC\n\tFHRpGadlNzKDE3fEdoMobxHB3Lm6FDml5GyBAA8+dQYVI0oDwJ3gpZPZ0J5Vx9RbqXe8RDuR\n\tdu90hvCJkq7/tzSQ0GeD3BwXb9/R/A4dVXhaDd91Q1qQXidI+2jwhx8iqiYxbT+DoAUkQRQy\n\txBtoCM1CxH7u45URUgD//fxYr3D4B1SlonA6vdaEdHZOGwECnDpTxecENMbz/Bx7qfrmd901\n\tD+N9SjIwrbVhhSyUXYnSUb8F+9g2RDY42Sk7GcYxIeON4VzKqWM7hpkXZ47pkK0YodO+dRKM\n\tyMcoUWrTK0Uz6UzUGKoJVbxmSW/EJLEGoI5p3NWxWtScEVv8mO49gqQdrRIOheZycDmHnItt\n\t9Qjv00uFhEwv2YfiyGk6iGF2W40s2pH2t6oeuGgmiZ7g6d0MEK8Ql/4zPItvr1c1rpwpXUC1\n\tu1kQWgtnNjFHX3KiYdqjcZeRBiry1X0zY+4Y24wUU0KsEewJwjhmCKAsju1RpdlPg2kC","In-Reply-To":"<20240819211534.GA4770@pendragon.ideasonboard.com>","Content-Type":"text/plain; charset=UTF-8; format=flowed","Content-Transfer-Encoding":"7bit","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","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "}},{"id":30867,"web_url":"https://patchwork.libcamera.org/comment/30867/","msgid":"<20240820074916.GC24895@pendragon.ideasonboard.com>","date":"2024-08-20T07:49:16","subject":"Re: [PATCH v3 3/7] Documentation: Synchronise camera stack details","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/people/2/","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"content":"Hi Dan,\n\nOn Tue, Aug 20, 2024 at 08:27:49AM +0100, Daniel Scally wrote:\n> On 19/08/2024 22:15, Laurent Pinchart wrote:\n> > On Mon, Aug 19, 2024 at 05:09:17PM +0100, Daniel Scally wrote:\n> >> There are two near-duplicate instances of the camera stack details\n> >> in the Documentation, in docs.rst and guides/introduction.rst. Remove\n> >> them from guides/introduction.rst, with the exception of the\n> >> explanations of the V4L2 Compatibility Layer and the Android HAL\n> >> which are moved to the Camera Stack section in docs.rst. The Docs\n> >> page already had its own separate version of those details but they\n> >> are distinct and seemingly out of date - remove them.\n> >>\n> >> Signed-off-by: Daniel Scally \n> >> ---\n> >> Changes since v2:\n> >>\n> >> \t- Refocused this patch to focus on camera stack section instead of the\n> >> \t libcamera architecture section. Dropped the R-b.\n> >>\n> >> Changes since v1:\n> >>\n> >> \t- None\n> >>\n> >>\n> >> Documentation/docs.rst | 56 +++++++------\n> >> Documentation/guides/introduction.rst | 109 +-------------------------\n> >> 2 files changed, 31 insertions(+), 134 deletions(-)\n> >>\n> >> diff --git a/Documentation/docs.rst b/Documentation/docs.rst\n> >> index 5871961c..0eacc924 100644\n> >> --- a/Documentation/docs.rst\n> >> +++ b/Documentation/docs.rst\n> >> @@ -239,6 +239,36 @@ The camera stack comprises four software layers. From bottom to top:\n> >> libcamera framework or libcamera adaptation, and are outside of\n> >> the scope of the libcamera project.\n> >> \n> >> +V4L2 Compatibility Layer\n> >> + V4L2 compatibility is achieved through a shared library that traps all\n> >> + accesses to camera devices and routes them to libcamera to emulate high-level\n> >> + V4L2 camera devices. It is injected in a process address space through\n> >> + ``LD_PRELOAD`` and is completely transparent for applications.\n> >> +\n> >> + The compatibility layer exposes camera device features on a best-effort basis,\n> >> + and aims for the level of features traditionally available from a UVC camera\n> >> + designed for video conferencing.\n> >> +\n> >> +Android Camera HAL\n> >> + Camera support for Android is achieved through a generic Android camera HAL\n> >> + implementation on top of libcamera. The HAL implements features required by\n> >> + Android and out of scope from libcamera, such as JPEG encoding support.\n> >> +\n> >> + This component is used to provide support for ChromeOS platforms\n> > s/$/./\n> >\n> >> +\n> >> +GStreamer element (gstlibcamerasrc)\n> >> + A `GStreamer element`_ is provided to allow capture from libcamera supported\n> >> + devices through GStreamer pipelines, and connect to other elements for further\n> >> + processing.\n> >> +\n> >> + Development of this element is ongoing and is limited to a single stream.\n> >\n> > This isn't true anymore, we now support multiple streams. This can be\n> > addressed in a separate patch, it's easier to review refactorings\n> > separately from documentation updates.\n> \n> Is the rest of the sentence worth retaining? Is the GStreamer element\n> still under active development?\n\nlibcamera is still under active development :-) I'd drop the sentence.\n\n> > Reviewed-by: Laurent Pinchart \n> >\n> >> +\n> >> +Native libcamera API\n> >> + Applications can make use of the libcamera API directly using the C++\n> >> + API. An example application and walkthrough using the libcamera API can be\n> >> + followed in the :doc:`Application writer's guide `\n> >> +\n> >> +.. _GStreamer element: https://gstreamer.freedesktop.org/documentation/application-development/basics/elements.html\n> >> \n> >> libcamera Architecture\n> >> ======================\n> >> @@ -374,29 +404,3 @@ Helpers and Support Classes\n> >> self-contained support classes, even if such code is present only once in the\n> >> code base, in order to keep the source code clean and easy to read. This\n> >> should be the case for instance for plugin management.\n> >> -\n> >> -\n> >> -V4L2 Compatibility Layer\n> >> -------------------------\n> >> -\n> >> -V4L2 compatibility is achieved through a shared library that traps all\n> >> -accesses to camera devices and routes them to libcamera to emulate high-level\n> >> -V4L2 camera devices. It is injected in a process address space through\n> >> -`LD_PRELOAD` and is completely transparent for applications.\n> >> -\n> >> -The compatibility layer exposes camera device features on a best-effort basis,\n> >> -and aims for the level of features traditionally available from a UVC camera\n> >> -designed for video conferencing.\n> >> -\n> >> -\n> >> -Android Camera HAL\n> >> -------------------\n> >> -\n> >> -Camera support for Android is achieved through a generic Android\n> >> -camera HAL implementation on top of libcamera. The HAL will implement internally\n> >> -features required by Android and missing from libcamera, such as JPEG encoding\n> >> -support.\n> >> -\n> >> -The Android camera HAL implementation will initially target the\n> >> -LIMITED hardware level, with support for the FULL level then being gradually\n> >> -implemented.\n> >> diff --git a/Documentation/guides/introduction.rst b/Documentation/guides/introduction.rst\n> >> index 8368bd4a..d1e67654 100644\n> >> --- a/Documentation/guides/introduction.rst\n> >> +++ b/Documentation/guides/introduction.rst\n> >> @@ -26,8 +26,7 @@ desirable results from the camera.\n> >> .. _Media Controller: https://www.linuxtv.org/downloads/v4l-dvb-apis-new/userspace-api/mediactl/media-controller.html\n> >> \n> >> \n> >> -In this developers guide, we will explore the `Camera Stack`_ and how it is\n> >> -can be visualised at a high level, and explore the internal `Architecture`_ of\n> >> +In this developers guide, we will explore the internal `Architecture`_ of\n> >> the libcamera library with its components. The current `Platform Support`_ is\n> >> detailed, as well as an overview of the `Licensing`_ requirements of the\n> >> project.\n> >> @@ -42,112 +41,6 @@ provides a tutorial of the key APIs exposed by libcamera.\n> >> \n> >> .. TODO: Correctly link to the other articles of the guide\n> >> \n> >> -Camera Stack\n> >> -------------\n> >> -\n> >> -The libcamera library is implemented in userspace, and makes use of underlying\n> >> -kernel drivers that directly interact with hardware.\n> >> -\n> >> -Applications can make use of libcamera through the native `libcamera API`_'s or\n> >> -through an adaptation layer integrating libcamera into a larger framework.\n> >> -\n> >> -.. _libcamera API: https://www.libcamera.org/api-html/index.html\n> >> -\n> >> -::\n> >> -\n> >> - Application Layer\n> >> - / +--------------+ +--------------+ +--------------+ +--------------+\n> >> - | | Native | | Framework | | Native | | Android |\n> >> - | | V4L2 | | Application | | libcamera | | Camera |\n> >> - | | Application | | (gstreamer) | | Application | | Framework |\n> >> - \\ +--------------+ +--------------+ +--------------+ +--------------+\n> >> -\n> >> - ^ ^ ^ ^\n> >> - | | | |\n> >> - | | | |\n> >> - v v | v\n> >> - Adaptation Layer |\n> >> - / +--------------+ +--------------+ | +--------------+\n> >> - | | V4L2 | | gstreamer | | | Android |\n> >> - | | Compatibility| | element | | | Camera |\n> >> - | | (preload) | |(libcamerasrc)| | | HAL |\n> >> - \\ +--------------+ +--------------+ | +--------------+\n> >> - |\n> >> - ^ ^ | ^\n> >> - | | | |\n> >> - | | | |\n> >> - v v v v\n> >> - libcamera Framework\n> >> - / +--------------------------------------------------------------------+\n> >> - | | |\n> >> - | | libcamera |\n> >> - | | |\n> >> - \\ +--------------------------------------------------------------------+\n> >> -\n> >> - ^ ^ ^\n> >> - Userspace | | |\n> >> - --------------------- | ---------------- | ---------------- | ---------------\n> >> - Kernel | | |\n> >> - v v v\n> >> -\n> >> - +-----------+ +-----------+ +-----------+\n> >> - | Media | <--> | Video | <--> | V4L2 |\n> >> - | Device | | Device | | Subdev |\n> >> - +-----------+ +-----------+ +-----------+\n> >> -\n> >> -The camera stack comprises of four software layers. From bottom to top:\n> >> -\n> >> -* The kernel drivers control the camera hardware and expose a low-level\n> >> - interface to userspace through the Linux kernel V4L2 family of APIs\n> >> - (Media Controller API, V4L2 Video Device API and V4L2 Subdev API).\n> >> -\n> >> -* The libcamera framework is the core part of the stack. It handles all control\n> >> - of the camera devices in its core component, libcamera, and exposes a native\n> >> - C++ API to upper layers.\n> >> -\n> >> -* The libcamera adaptation layer is an umbrella term designating the components\n> >> - that interface to libcamera in other frameworks. Notable examples are the V4L2\n> >> - compatibility layer, the gstreamer libcamera element, and the Android camera\n> >> - HAL implementation based on libcamera which are provided as a part of the\n> >> - libcamera project.\n> >> -\n> >> -* The applications and upper level frameworks are based on the libcamera\n> >> - framework or libcamera adaptation, and are outside of the scope of the\n> >> - libcamera project, however example native applications (cam, qcam) are\n> >> - provided for testing.\n> >> -\n> >> -\n> >> -V4L2 Compatibility Layer\n> >> - V4L2 compatibility is achieved through a shared library that traps all\n> >> - accesses to camera devices and routes them to libcamera to emulate high-level\n> >> - V4L2 camera devices. It is injected in a process address space through\n> >> - ``LD_PRELOAD`` and is completely transparent for applications.\n> >> -\n> >> - The compatibility layer exposes camera device features on a best-effort basis,\n> >> - and aims for the level of features traditionally available from a UVC camera\n> >> - designed for video conferencing.\n> >> -\n> >> -Android Camera HAL\n> >> - Camera support for Android is achieved through a generic Android camera HAL\n> >> - implementation on top of libcamera. The HAL implements features required by\n> >> - Android and out of scope from libcamera, such as JPEG encoding support.\n> >> -\n> >> - This component is used to provide support for ChromeOS platforms\n> >> -\n> >> -GStreamer element (gstlibcamerasrc)\n> >> - A `GStreamer element`_ is provided to allow capture from libcamera supported\n> >> - devices through GStreamer pipelines, and connect to other elements for further\n> >> - processing.\n> >> -\n> >> - Development of this element is ongoing and is limited to a single stream.\n> >> -\n> >> -Native libcamera API\n> >> - Applications can make use of the libcamera API directly using the C++\n> >> - API. An example application and walkthrough using the libcamera API can be\n> >> - followed in the `Application Writers Guide`_\n> >> -\n> >> -.. _GStreamer element: https://gstreamer.freedesktop.org/documentation/application-development/basics/elements.html\n> >> -\n> >> Architecture\n> >> ------------\n> >>","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 52368C323E\n\tfor ;\n\tTue, 20 Aug 2024 07:49:46 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 4D42A633CE;\n\tTue, 20 Aug 2024 09:49:45 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 5EFA363369\n\tfor ;\n\tTue, 20 Aug 2024 09:49:44 +0200 (CEST)","from pendragon.ideasonboard.com (81-175-209-231.bb.dnainternet.fi\n\t[81.175.209.231])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 62917581;\n\tTue, 20 Aug 2024 09:48:42 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"hM9RYufM\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1724140122;\n\tbh=h01HmVZx+mjMOl2+1sVRf82+eHTkTHxn+z/PEEGOh9M=;\n\th=Date:From:To:Cc:Subject:References:In-Reply-To:From;\n\tb=hM9RYufMCrZFvJRJISzz5WxBi6dXOB81Uo0rl9tcBEOGnilXB0OfHV6l0vUU9bQB2\n\tZIiys163QO2QtG6iKHZNKjy/+M+mBeeUcmm64aR/5mACBSvTbUHtAre+0QZDloLtJt\n\tBm1HXK6XDdhzxPao/fcRP2Ibv5ULjslOMJq8znQg=","Date":"Tue, 20 Aug 2024 10:49:16 +0300","From":"Laurent Pinchart ","To":"Dan Scally ","Cc":"libcamera-devel@lists.libcamera.org","Subject":"Re: [PATCH v3 3/7] Documentation: Synchronise camera stack details","Message-ID":"<20240820074916.GC24895@pendragon.ideasonboard.com>","References":"<20240819160921.468981-1-dan.scally@ideasonboard.com>\n\t<20240819160921.468981-4-dan.scally@ideasonboard.com>\n\t<20240819211534.GA4770@pendragon.ideasonboard.com>\n\t<70a0f847-3ca7-4e9c-82f9-e4829e45377a@ideasonboard.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=utf-8","Content-Disposition":"inline","In-Reply-To":"<70a0f847-3ca7-4e9c-82f9-e4829e45377a@ideasonboard.com>","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","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "}}]