From 6f48cb78b60fbb8ccb4531b31a260b7ee60d00db Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Sz=C3=A9kely=20G=C3=A1bor?= Date: Mon, 26 Feb 2024 08:30:56 +0100 Subject: [PATCH] Merge pull request #25084 from EDVTAZ:emscripten-3.1.54-compat Add compatibility with latest (3.1.54) emsdk version #25084 ### Pull Request Readiness Checklist See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request - [x] I agree to contribute to the project under Apache 2 License. - [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV - [ ] The PR is proposed to the proper branch - [ ] There is a reference to the original bug report and related work - [ ] There is accuracy test, performance test and test data in opencv_extra repository, if applicable Patch to opencv_extra has the same branch name. - [ ] The feature is well documented and sample code can be built with the project CMake ### Details I was following [this tutorial](https://docs.opencv.org/4.9.0/d4/da1/tutorial_js_setup.html) for building opencv with wasm target. The tutorial mentions that the last verified version of emscripten that is tested with opencv is 2.0.10, but I was curious if I could get it to work with more recent versions. I've run into a few issues with the latest version, for which fixes are included in this PR. I've found a few issues that have the same problems I encountered: - https://github.com/opencv/opencv/issues/24620 - https://github.com/opencv/opencv/issues/20313 - https://stackoverflow.com/questions/77469603/custom-opencv-js-wasm-using-cv-matfromarray-results-in-cv-mat-is-not-a-co - https://github.com/emscripten-core/emscripten/issues/14803 - https://github.com/opencv/opencv/issues/24572 - https://github.com/opencv/opencv/issues/19493#issuecomment-857167996 I used the docker image for building and comparing results with different emsdk versions. I tested by building with `--build_wasm` and `--build-test` flags and ran the tests in the browser. I addressed the following issues with newer versions of emscripten: - In newer versions `EMSCRIPTEN` environemnt variable was stopped being set. I added support for deriving location based on the `EMSDK` environment variable, as suggested [here](https://github.com/emscripten-core/emscripten/issues/14803) - In newer versions emcmake started passing `-DCMAKE...` arguments, however the opencv python script didn't know how to handle them. I added processing to the args that will forward all arguments to `cmake` that start with `-D`. I opted for this in hopes of being more futureproof, but another approach could be just ignoreing them, or explicitly forwarding them instead of matching anything starting with `-D`. These approches were suggested [here](https://github.com/opencv/opencv/issues/19493#issuecomment-855529448) - With [version 3.1.31](https://github.com/emscripten-core/emscripten/blob/main/ChangeLog.md#3131---012623) some previously exported functions stopped being automatically exported. Because of this, `_free` and `_malloc` were no longer available and had to be explicitly exported because of breaking tests. - With [version 3.1.42](https://github.com/emscripten-core/emscripten/compare/3.1.41...3.1.42#diff-e505aa80b2764c0197acfc9afd8179b3600f0ab5dd00ff77db01879a84515cdbL3875) the `post-js` code doesn't receive the module named as `EXPORT_NAME` anymore, but only as `moduleArg`/`Module`. This broke existing code in `helpers.js`, which was referencing exported functions through `cv.Mat`, etc. I changed all of these references to use `Module.Mat`, etc. If it is preferred, alternatively the `cv` variable could be reintroduced in `helper.js` as suggested [here](https://github.com/opencv/opencv/issues/24620) With the above changes in place, I can successfully build and run tests with the latest emscripten/emsdk docker image (also with 2.0.10 and most of the other older tags, except for a few that contain transient issues like [this](https://github.com/emscripten-core/emscripten/issues/17700)). This is my first time contributing to opencv, so I hope I got everything correct in this PR, but please let me know if I should change anything! --- modules/js/src/helpers.js | 4 ++++ platforms/js/build_js.py | 15 ++++++++++----- 2 files changed, 14 insertions(+), 5 deletions(-) diff --git a/modules/js/src/helpers.js b/modules/js/src/helpers.js index 9f1934c279..962a0b4d90 100644 --- a/modules/js/src/helpers.js +++ b/modules/js/src/helpers.js @@ -42,6 +42,10 @@ if (typeof Module.FS === 'undefined' && typeof FS !== 'undefined') { Module.FS = FS; } +if (typeof cv === 'undefined') { + var cv = Module; +} + Module['imread'] = function(imageSource) { var img = null; if (typeof imageSource === 'string') { diff --git a/platforms/js/build_js.py b/platforms/js/build_js.py index 07fda10d35..f0701212af 100644 --- a/platforms/js/build_js.py +++ b/platforms/js/build_js.py @@ -84,7 +84,6 @@ class Builder: "-DPYTHON_DEFAULT_EXECUTABLE=%s" % sys.executable, "-DENABLE_PIC=FALSE", # To workaround emscripten upstream backend issue https://github.com/emscripten-core/emscripten/issues/8761 "-DCMAKE_BUILD_TYPE=Release", - "-DCMAKE_TOOLCHAIN_FILE='%s'" % self.get_toolchain_file(), "-DCPU_BASELINE=''", "-DCMAKE_INSTALL_PREFIX=/usr/local", "-DCPU_DISPATCH=''", @@ -145,6 +144,8 @@ class Builder: "-DBUILD_PERF_TESTS=ON"] if self.options.cmake_option: cmd += self.options.cmake_option + if not self.options.cmake_option or all(["-DCMAKE_TOOLCHAIN_FILE" not in opt for opt in self.options.cmake_option]): + cmd.append("-DCMAKE_TOOLCHAIN_FILE='%s'" % self.get_toolchain_file()) if self.options.build_doc: cmd.append("-DBUILD_DOCS=ON") else: @@ -194,6 +195,7 @@ class Builder: flags += self.options.build_flags if self.options.webnn: flags += "-s USE_WEBNN=1 " + flags += "-s EXPORTED_FUNCTIONS=\"['_malloc', '_free']\"" return flags def config(self): @@ -224,10 +226,12 @@ if __name__ == "__main__": opencv_dir = os.path.abspath(os.path.join(SCRIPT_DIR, '../..')) emscripten_dir = None - if "EMSCRIPTEN" in os.environ: + if "EMSDK" in os.environ: + emscripten_dir = os.path.join(os.environ["EMSDK"], "upstream", "emscripten") + elif "EMSCRIPTEN" in os.environ: emscripten_dir = os.environ["EMSCRIPTEN"] else: - log.warning("EMSCRIPTEN environment variable is not available. Please properly activate Emscripten SDK and consider using 'emcmake' launcher") + log.warning("EMSCRIPTEN/EMSDK environment variable is not available. Please properly activate Emscripten SDK and consider using 'emcmake' launcher") parser = argparse.ArgumentParser(description='Build OpenCV.js by Emscripten') parser.add_argument("build_dir", help="Building directory (and output)") @@ -256,7 +260,8 @@ if __name__ == "__main__": help="Specify configuration file with own list of exported into JS functions") parser.add_argument('--webnn', action="store_true", help="Enable WebNN Backend") - args = parser.parse_args() + transformed_args = ["--cmake_option=%s".format(arg) if arg[:2] == "-D" else arg for arg in sys.argv[1:]] + args = parser.parse_args(transformed_args) log.debug("Args: %s", args) @@ -266,7 +271,7 @@ if __name__ == "__main__": del os.environ['EMMAKEN_JUST_CONFIGURE'] # avoid linker errors with NODERAWFS message then using 'emcmake' launcher if args.emscripten_dir is None: - log.error("Cannot get Emscripten path, please use 'emcmake' launcher or specify it either by EMSCRIPTEN environment variable or --emscripten_dir option.") + log.error("Cannot get Emscripten path, please use 'emcmake' launcher or specify it either by EMSCRIPTEN/EMSDK environment variable or --emscripten_dir option.") sys.exit(-1) builder = Builder(args)