{"id":19957,"url":"https://patchwork.libcamera.org/api/patches/19957/?format=json","web_url":"https://patchwork.libcamera.org/patch/19957/","project":{"id":1,"url":"https://patchwork.libcamera.org/api/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":"<20240426073612.1230283-3-paul.elder@ideasonboard.com>","date":"2024-04-26T07:36:10","name":"[v2,2/4] ipa: libipa: Copy pwl from rpi","commit_ref":null,"pull_url":null,"state":"superseded","archived":false,"hash":"4472b53543357d0eff175faec022d83d3db073f3","submitter":{"id":17,"url":"https://patchwork.libcamera.org/api/people/17/?format=json","name":"Paul Elder","email":"paul.elder@ideasonboard.com"},"delegate":null,"mbox":"https://patchwork.libcamera.org/patch/19957/mbox/","series":[{"id":4275,"url":"https://patchwork.libcamera.org/api/series/4275/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=4275","date":"2024-04-26T07:36:08","name":"ipa: Move Pwl from Raspberry Pi to libipa","version":2,"mbox":"https://patchwork.libcamera.org/series/4275/mbox/"}],"comments":"https://patchwork.libcamera.org/api/patches/19957/comments/","check":"pending","checks":"https://patchwork.libcamera.org/api/patches/19957/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 1B7D2C3220\n\tfor ;\n\tFri, 26 Apr 2024 07:36:32 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 95A1F63415;\n\tFri, 26 Apr 2024 09:36:31 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id D2430633EA\n\tfor ;\n\tFri, 26 Apr 2024 09:36:27 +0200 (CEST)","from pyrite.hamster-moth.ts.net (h175-177-049-156.catv02.itscom.jp\n\t[175.177.49.156])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 4CA6266B;\n\tFri, 26 Apr 2024 09:35:32 +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=\"USmWwk1A\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1714116934;\n\tbh=3K4KFP1JTyWl3WRkRXYnGCU6FgmW3DcEeBBX/EP1yfc=;\n\th=From:To:Cc:Subject:Date:In-Reply-To:References:From;\n\tb=USmWwk1A+4JnDVV38fh16xgSLR25WzaGqHxV0nS+/9L4xGsT9o1Yg9tbN+cviDQzI\n\tXZpBF4LsSPQbwJ0TIWvPDvKsjJK0WxjJvek7luLrG8w6ZAc2y+ZYAaxZ/+BiE1eh1K\n\tWee8LCMkuvrYNEiAsx4eVLnYjrErIemPXvGV7Yaw=","From":"Paul Elder ","To":"libcamera-devel@lists.libcamera.org","Cc":"Paul Elder ,\n\tStefan Klug ","Subject":"[PATCH v2 2/4] ipa: libipa: Copy pwl from rpi","Date":"Fri, 26 Apr 2024 16:36:10 +0900","Message-Id":"<20240426073612.1230283-3-paul.elder@ideasonboard.com>","X-Mailer":"git-send-email 2.39.2","In-Reply-To":"<20240426073612.1230283-1-paul.elder@ideasonboard.com>","References":"<20240426073612.1230283-1-paul.elder@ideasonboard.com>","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":"","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\" "},"content":"Copy the piecewise linear function code from Raspberry Pi.\n\nSigned-off-by: Paul Elder \nReviewed-by: Stefan Klug \n\n---\nNo change in v2\n---\n src/ipa/libipa/meson.build | 2 +\n src/ipa/libipa/pwl.cpp | 267 +++++++++++++++++++++++++++++++++++++\n src/ipa/libipa/pwl.h | 123 +++++++++++++++++\n 3 files changed, 392 insertions(+)\n create mode 100644 src/ipa/libipa/pwl.cpp\n create mode 100644 src/ipa/libipa/pwl.h","diff":"diff --git a/src/ipa/libipa/meson.build b/src/ipa/libipa/meson.build\nindex 7ce885da..1b3faf8d 100644\n--- a/src/ipa/libipa/meson.build\n+++ b/src/ipa/libipa/meson.build\n@@ -8,6 +8,7 @@ libipa_headers = files([\n 'fc_queue.h',\n 'histogram.h',\n 'module.h',\n+ 'pwl.h',\n ])\n \n libipa_sources = files([\n@@ -18,6 +19,7 @@ libipa_sources = files([\n 'fc_queue.cpp',\n 'histogram.cpp',\n 'module.cpp',\n+ 'pwl.cpp'\n ])\n \n libipa_includes = include_directories('..')\ndiff --git a/src/ipa/libipa/pwl.cpp b/src/ipa/libipa/pwl.cpp\nnew file mode 100644\nindex 00000000..09f5d65c\n--- /dev/null\n+++ b/src/ipa/libipa/pwl.cpp\n@@ -0,0 +1,267 @@\n+/* SPDX-License-Identifier: BSD-2-Clause */\n+/*\n+ * Copyright (C) 2019, Raspberry Pi Ltd\n+ *\n+ * pwl.cpp - piecewise linear functions\n+ */\n+\n+#include \n+#include \n+#include \n+\n+#include \"pwl.h\"\n+\n+int Pwl::read(const libcamera::YamlObject ¶ms)\n+{\n+\tif (!params.size() || params.size() % 2)\n+\t\treturn -EINVAL;\n+\n+\tconst auto &list = params.asList();\n+\n+\tfor (auto it = list.begin(); it != list.end(); it++) {\n+\t\tauto x = it->get();\n+\t\tif (!x)\n+\t\t\treturn -EINVAL;\n+\t\tif (it != list.begin() && *x <= points_.back().x)\n+\t\t\treturn -EINVAL;\n+\n+\t\tauto y = (++it)->get();\n+\t\tif (!y)\n+\t\t\treturn -EINVAL;\n+\n+\t\tpoints_.push_back(Point(*x, *y));\n+\t}\n+\n+\treturn 0;\n+}\n+\n+void Pwl::append(double x, double y, const double eps)\n+{\n+\tif (points_.empty() || points_.back().x + eps < x)\n+\t\tpoints_.push_back(Point(x, y));\n+}\n+\n+void Pwl::prepend(double x, double y, const double eps)\n+{\n+\tif (points_.empty() || points_.front().x - eps > x)\n+\t\tpoints_.insert(points_.begin(), Point(x, y));\n+}\n+\n+Pwl::Interval Pwl::domain() const\n+{\n+\treturn Interval(points_[0].x, points_[points_.size() - 1].x);\n+}\n+\n+Pwl::Interval Pwl::range() const\n+{\n+\tdouble lo = points_[0].y, hi = lo;\n+\tfor (auto &p : points_)\n+\t\tlo = std::min(lo, p.y), hi = std::max(hi, p.y);\n+\treturn Interval(lo, hi);\n+}\n+\n+bool Pwl::empty() const\n+{\n+\treturn points_.empty();\n+}\n+\n+double Pwl::eval(double x, int *spanPtr, bool updateSpan) const\n+{\n+\tint span = findSpan(x, spanPtr && *spanPtr != -1 ? *spanPtr : points_.size() / 2 - 1);\n+\tif (spanPtr && updateSpan)\n+\t\t*spanPtr = span;\n+\treturn points_[span].y +\n+\t (x - points_[span].x) * (points_[span + 1].y - points_[span].y) /\n+\t\t (points_[span + 1].x - points_[span].x);\n+}\n+\n+int Pwl::findSpan(double x, int span) const\n+{\n+\t/*\n+\t * Pwls are generally small, so linear search may well be faster than\n+\t * binary, though could review this if large PWls start turning up.\n+\t */\n+\tint lastSpan = points_.size() - 2;\n+\t/*\n+\t * some algorithms may call us with span pointing directly at the last\n+\t * control point\n+\t */\n+\tspan = std::max(0, std::min(lastSpan, span));\n+\twhile (span < lastSpan && x >= points_[span + 1].x)\n+\t\tspan++;\n+\twhile (span && x < points_[span].x)\n+\t\tspan--;\n+\treturn span;\n+}\n+\n+Pwl::PerpType Pwl::invert(Point const &xy, Point &perp, int &span,\n+\t\t\t const double eps) const\n+{\n+\tassert(span >= -1);\n+\tbool prevOffEnd = false;\n+\tfor (span = span + 1; span < (int)points_.size() - 1; span++) {\n+\t\tPoint spanVec = points_[span + 1] - points_[span];\n+\t\tdouble t = ((xy - points_[span]) % spanVec) / spanVec.len2();\n+\t\tif (t < -eps) /* off the start of this span */\n+\t\t{\n+\t\t\tif (span == 0) {\n+\t\t\t\tperp = points_[span];\n+\t\t\t\treturn PerpType::Start;\n+\t\t\t} else if (prevOffEnd) {\n+\t\t\t\tperp = points_[span];\n+\t\t\t\treturn PerpType::Vertex;\n+\t\t\t}\n+\t\t} else if (t > 1 + eps) /* off the end of this span */\n+\t\t{\n+\t\t\tif (span == (int)points_.size() - 2) {\n+\t\t\t\tperp = points_[span + 1];\n+\t\t\t\treturn PerpType::End;\n+\t\t\t}\n+\t\t\tprevOffEnd = true;\n+\t\t} else /* a true perpendicular */\n+\t\t{\n+\t\t\tperp = points_[span] + spanVec * t;\n+\t\t\treturn PerpType::Perpendicular;\n+\t\t}\n+\t}\n+\treturn PerpType::None;\n+}\n+\n+Pwl Pwl::inverse(bool *trueInverse, const double eps) const\n+{\n+\tbool appended = false, prepended = false, neither = false;\n+\tPwl inverse;\n+\n+\tfor (Point const &p : points_) {\n+\t\tif (inverse.empty())\n+\t\t\tinverse.append(p.y, p.x, eps);\n+\t\telse if (std::abs(inverse.points_.back().x - p.y) <= eps ||\n+\t\t\t std::abs(inverse.points_.front().x - p.y) <= eps)\n+\t\t\t/* do nothing */;\n+\t\telse if (p.y > inverse.points_.back().x) {\n+\t\t\tinverse.append(p.y, p.x, eps);\n+\t\t\tappended = true;\n+\t\t} else if (p.y < inverse.points_.front().x) {\n+\t\t\tinverse.prepend(p.y, p.x, eps);\n+\t\t\tprepended = true;\n+\t\t} else\n+\t\t\tneither = true;\n+\t}\n+\n+\t/*\n+\t * This is not a proper inverse if we found ourselves putting points\n+\t * onto both ends of the inverse, or if there were points that couldn't\n+\t * go on either.\n+\t */\n+\tif (trueInverse)\n+\t\t*trueInverse = !(neither || (appended && prepended));\n+\n+\treturn inverse;\n+}\n+\n+Pwl Pwl::compose(Pwl const &other, const double eps) const\n+{\n+\tdouble thisX = points_[0].x, thisY = points_[0].y;\n+\tint thisSpan = 0, otherSpan = other.findSpan(thisY, 0);\n+\tPwl result({ { thisX, other.eval(thisY, &otherSpan, false) } });\n+\twhile (thisSpan != (int)points_.size() - 1) {\n+\t\tdouble dx = points_[thisSpan + 1].x - points_[thisSpan].x,\n+\t\t dy = points_[thisSpan + 1].y - points_[thisSpan].y;\n+\t\tif (std::abs(dy) > eps &&\n+\t\t otherSpan + 1 < (int)other.points_.size() &&\n+\t\t points_[thisSpan + 1].y >=\n+\t\t\t other.points_[otherSpan + 1].x + eps) {\n+\t\t\t/*\n+\t\t\t * next control point in result will be where this\n+\t\t\t * function's y reaches the next span in other\n+\t\t\t */\n+\t\t\tthisX = points_[thisSpan].x +\n+\t\t\t\t(other.points_[otherSpan + 1].x -\n+\t\t\t\t points_[thisSpan].y) *\n+\t\t\t\t\tdx / dy;\n+\t\t\tthisY = other.points_[++otherSpan].x;\n+\t\t} else if (std::abs(dy) > eps && otherSpan > 0 &&\n+\t\t\t points_[thisSpan + 1].y <=\n+\t\t\t\t other.points_[otherSpan - 1].x - eps) {\n+\t\t\t/*\n+\t\t\t * next control point in result will be where this\n+\t\t\t * function's y reaches the previous span in other\n+\t\t\t */\n+\t\t\tthisX = points_[thisSpan].x +\n+\t\t\t\t(other.points_[otherSpan + 1].x -\n+\t\t\t\t points_[thisSpan].y) *\n+\t\t\t\t\tdx / dy;\n+\t\t\tthisY = other.points_[--otherSpan].x;\n+\t\t} else {\n+\t\t\t/* we stay in the same span in other */\n+\t\t\tthisSpan++;\n+\t\t\tthisX = points_[thisSpan].x,\n+\t\t\tthisY = points_[thisSpan].y;\n+\t\t}\n+\t\tresult.append(thisX, other.eval(thisY, &otherSpan, false),\n+\t\t\t eps);\n+\t}\n+\treturn result;\n+}\n+\n+void Pwl::map(std::function f) const\n+{\n+\tfor (auto &pt : points_)\n+\t\tf(pt.x, pt.y);\n+}\n+\n+void Pwl::map2(Pwl const &pwl0, Pwl const &pwl1,\n+\t std::function f)\n+{\n+\tint span0 = 0, span1 = 0;\n+\tdouble x = std::min(pwl0.points_[0].x, pwl1.points_[0].x);\n+\tf(x, pwl0.eval(x, &span0, false), pwl1.eval(x, &span1, false));\n+\twhile (span0 < (int)pwl0.points_.size() - 1 ||\n+\t span1 < (int)pwl1.points_.size() - 1) {\n+\t\tif (span0 == (int)pwl0.points_.size() - 1)\n+\t\t\tx = pwl1.points_[++span1].x;\n+\t\telse if (span1 == (int)pwl1.points_.size() - 1)\n+\t\t\tx = pwl0.points_[++span0].x;\n+\t\telse if (pwl0.points_[span0 + 1].x > pwl1.points_[span1 + 1].x)\n+\t\t\tx = pwl1.points_[++span1].x;\n+\t\telse\n+\t\t\tx = pwl0.points_[++span0].x;\n+\t\tf(x, pwl0.eval(x, &span0, false), pwl1.eval(x, &span1, false));\n+\t}\n+}\n+\n+Pwl Pwl::combine(Pwl const &pwl0, Pwl const &pwl1,\n+\t\t std::function f,\n+\t\t const double eps)\n+{\n+\tPwl result;\n+\tmap2(pwl0, pwl1, [&](double x, double y0, double y1) {\n+\t\tresult.append(x, f(x, y0, y1), eps);\n+\t});\n+\treturn result;\n+}\n+\n+void Pwl::matchDomain(Interval const &domain, bool clip, const double eps)\n+{\n+\tint span = 0;\n+\tprepend(domain.start, eval(clip ? points_[0].x : domain.start, &span),\n+\t\teps);\n+\tspan = points_.size() - 2;\n+\tappend(domain.end, eval(clip ? points_.back().x : domain.end, &span),\n+\t eps);\n+}\n+\n+Pwl &Pwl::operator*=(double d)\n+{\n+\tfor (auto &pt : points_)\n+\t\tpt.y *= d;\n+\treturn *this;\n+}\n+\n+void Pwl::debug(FILE *fp) const\n+{\n+\tfprintf(fp, \"Pwl {\\n\");\n+\tfor (auto &p : points_)\n+\t\tfprintf(fp, \"\\t(%g, %g)\\n\", p.x, p.y);\n+\tfprintf(fp, \"}\\n\");\n+}\ndiff --git a/src/ipa/libipa/pwl.h b/src/ipa/libipa/pwl.h\nnew file mode 100644\nindex 00000000..7a6a6452\n--- /dev/null\n+++ b/src/ipa/libipa/pwl.h\n@@ -0,0 +1,123 @@\n+/* SPDX-License-Identifier: BSD-2-Clause */\n+/*\n+ * Copyright (C) 2019, Raspberry Pi Ltd\n+ *\n+ * pwl.h - piecewise linear functions interface\n+ */\n+#pragma once\n+\n+#include \n+#include \n+#include \n+\n+#include \"libcamera/internal/yaml_parser.h\"\n+\n+class Pwl\n+{\n+public:\n+\tstruct Interval {\n+\t\tInterval(double _start, double _end)\n+\t\t\t: start(_start), end(_end)\n+\t\t{\n+\t\t}\n+\t\tdouble start, end;\n+\t\tbool contains(double value)\n+\t\t{\n+\t\t\treturn value >= start && value <= end;\n+\t\t}\n+\t\tdouble clip(double value)\n+\t\t{\n+\t\t\treturn value < start ? start\n+\t\t\t\t\t : (value > end ? end : value);\n+\t\t}\n+\t\tdouble len() const { return end - start; }\n+\t};\n+\tstruct Point {\n+\t\tPoint() : x(0), y(0) {}\n+\t\tPoint(double _x, double _y)\n+\t\t\t: x(_x), y(_y) {}\n+\t\tdouble x, y;\n+\t\tPoint operator-(Point const &p) const\n+\t\t{\n+\t\t\treturn Point(x - p.x, y - p.y);\n+\t\t}\n+\t\tPoint operator+(Point const &p) const\n+\t\t{\n+\t\t\treturn Point(x + p.x, y + p.y);\n+\t\t}\n+\t\tdouble operator%(Point const &p) const\n+\t\t{\n+\t\t\treturn x * p.x + y * p.y;\n+\t\t}\n+\t\tPoint operator*(double f) const { return Point(x * f, y * f); }\n+\t\tPoint operator/(double f) const { return Point(x / f, y / f); }\n+\t\tdouble len2() const { return x * x + y * y; }\n+\t\tdouble len() const { return sqrt(len2()); }\n+\t};\n+\tPwl() {}\n+\tPwl(std::vector const &points) : points_(points) {}\n+\tint read(const libcamera::YamlObject ¶ms);\n+\tvoid append(double x, double y, const double eps = 1e-6);\n+\tvoid prepend(double x, double y, const double eps = 1e-6);\n+\tInterval domain() const;\n+\tInterval range() const;\n+\tbool empty() const;\n+\t/*\n+\t * Evaluate Pwl, optionally supplying an initial guess for the\n+\t * \"span\". The \"span\" may be optionally be updated. If you want to know\n+\t * the \"span\" value but don't have an initial guess you can set it to\n+\t * -1.\n+\t */\n+\tdouble eval(double x, int *spanPtr = nullptr,\n+\t\t bool updateSpan = true) const;\n+\t/*\n+\t * Find perpendicular closest to xy, starting from span+1 so you can\n+\t * call it repeatedly to check for multiple closest points (set span to\n+\t * -1 on the first call). Also returns \"pseudo\" perpendiculars; see\n+\t * PerpType enum.\n+\t */\n+\tenum class PerpType {\n+\t\tNone, /* no perpendicular found */\n+\t\tStart, /* start of Pwl is closest point */\n+\t\tEnd, /* end of Pwl is closest point */\n+\t\tVertex, /* vertex of Pwl is closest point */\n+\t\tPerpendicular /* true perpendicular found */\n+\t};\n+\tPerpType invert(Point const &xy, Point &perp, int &span,\n+\t\t\tconst double eps = 1e-6) const;\n+\t/*\n+\t * Compute the inverse function. Indicate if it is a proper (true)\n+\t * inverse, or only a best effort (e.g. input was non-monotonic).\n+\t */\n+\tPwl inverse(bool *trueInverse = nullptr, const double eps = 1e-6) const;\n+\t/* Compose two Pwls together, doing \"this\" first and \"other\" after. */\n+\tPwl compose(Pwl const &other, const double eps = 1e-6) const;\n+\t/* Apply function to (x,y) values at every control point. */\n+\tvoid map(std::function f) const;\n+\t/*\n+\t * Apply function to (x, y0, y1) values wherever either Pwl has a\n+\t * control point.\n+\t */\n+\tstatic void map2(Pwl const &pwl0, Pwl const &pwl1,\n+\t\t\t std::function f);\n+\t/*\n+\t * Combine two Pwls, meaning we create a new Pwl where the y values are\n+\t * given by running f wherever either has a knot.\n+\t */\n+\tstatic Pwl\n+\tcombine(Pwl const &pwl0, Pwl const &pwl1,\n+\t\tstd::function f,\n+\t\tconst double eps = 1e-6);\n+\t/*\n+\t * Make \"this\" match (at least) the given domain. Any extension my be\n+\t * clipped or linear.\n+\t */\n+\tvoid matchDomain(Interval const &domain, bool clip = true,\n+\t\t\t const double eps = 1e-6);\n+\tPwl &operator*=(double d);\n+\tvoid debug(FILE *fp = stdout) const;\n+\n+private:\n+\tint findSpan(double x, int span) const;\n+\tstd::vector points_;\n+};\n","prefixes":["v2","2/4"]}