{"record":{"id":"1cc87dacb497ee08","repo":"Yalantis/uCrop","slug":"load-gif-external-specified-filename-is-null","errorCode":null,"errorMessage":"load_gif_external(): Specified filename is (null) or does not exist.","messagePattern":"load_gif_external\\(\\): Specified filename is \\(null\\) or does not exist\\.","errorType":"exception","errorClass":"CImgArgumentException","httpStatus":null,"severity":"error","filePath":"ucrop/src/main/jni/CImg.h","lineNumber":67507,"sourceCode":"        throw CImgIOException(_cimglist_instance\n                              \"load_ffmpeg_external(): Failed to open file '%s' with external command 'ffmpeg'.\",\n                              cimglist_instance,\n                              filename);\n      return *this;\n    }\n\n    //! Load an image from a video file using the external tool 'ffmpeg' \\newinstance.\n    static CImgList<T> get_load_ffmpeg_external(const char *const filename) {\n      return CImgList<T>().load_ffmpeg_external(filename);\n    }\n\n    //! Load gif file, using ImageMagick or GraphicsMagick's external tools.\n    /**\n      \\param filename Filename to read data from.\n    **/\n    CImgList<T>& load_gif_external(const char *const filename) {\n      if (!filename || !cimg::is_file(filename))\n        throw CImgArgumentException(_cimglist_instance\n                                    \"load_gif_external(): Specified filename is (null) or does not exist.\",\n                                    cimglist_instance);\n      if (!_load_gif_external(filename,false))\n        if (!_load_gif_external(filename,true))\n          try { assign(CImg<T>().load_other(filename)); } catch (CImgException&) { assign(); }\n      if (is_empty())\n        throw CImgIOException(_cimglist_instance\n                              \"load_gif_external(): Failed to open file '%s'.\",\n                              cimglist_instance,filename);\n      return *this;\n    }\n\n    CImgList<T>& _load_gif_external(const char *const filename, const bool use_graphicsmagick=false) {\n      CImg<charT> command(1024), filename_tmp(256), filename_tmp2(256);\n      do {\n        cimg_snprintf(filename_tmp,filename_tmp._width,\"%s%c%s\",\n                      cimg::temporary_path(),cimg_file_separator,cimg::filenamerand());\n        if (use_graphicsmagick) cimg_snprintf(filename_tmp2,filename_tmp2._width,\"%s.png.0\",filename_tmp._data);","sourceCodeStart":67489,"sourceCodeEnd":67525,"githubUrl":"https://github.com/Yalantis/uCrop/blob/f788b534b48c144edf786c8cddbf0e029e637804/ucrop/src/main/jni/CImg.h#L67489-L67525","documentation":"CImgList::load_gif_external() reads GIFs via ImageMagick/GraphicsMagick's external tools. Before invoking anything, it validates the filename and throws this CImgArgumentException if the pointer is null or the path is not an existing regular file. It is a pure input-validation failure raised before any conversion is attempted.","triggerScenarios":"Calling load_gif_external(nullptr), or with a path that does not exist, is a directory, or is otherwise not a regular file.","commonSituations":"Wrong relative path / working directory; animated GIF deleted or renamed before load; native code on Android given a resource ID or URI instead of an extracted file path.","solutions":["Verify the path exists and is a regular file (std::filesystem::is_regular_file) before calling.","Use absolute paths and confirm the working directory for relative ones.","Extract Android content:// or resource URIs to a cache file first, then pass that path."],"exampleFix":"// before\nlist.load_gif_external(\"assets/anim.gif\"); // never extracted to disk\n\n// after\n// extract APK asset to cache first\nstd::string path = extractAssetToCache(\"anim.gif\");\nif (std::filesystem::is_regular_file(path))\n  list.load_gif_external(path.c_str());","handlingStrategy":"validation","validationCode":"bool usableGif(const char* p) {\n  return p != nullptr && std::filesystem::is_regular_file(p);\n}\nif (!usableGif(path)) { /* resolve path first */ }","typeGuard":"bool isExistingFile(const char* p) {\n  return p != nullptr && std::filesystem::exists(p) &&\n         std::filesystem::is_regular_file(p);\n}","tryCatchPattern":"try {\n  list.load_gif_external(path);\n} catch (CImgArgumentException&) {\n  // invalid/missing path: report to caller\n}","preventionTips":["Validate the GIF path with std::filesystem before calling.","Extract Android resources/URIs to real cache files before loading.","Use absolute paths and avoid relying on the current working directory."],"tags":["cimg","gif","file-not-found","imagemagick","external-tool"],"backgroundTag":"file-not-found","analyzedSha":"f788b534b48c144edf786c8cddbf0e029e637804","analyzedAt":"2026-09-08T08:36:04.887Z","contentChangedAt":"2026-09-08T08:36:04.887Z","schemaVersion":2},"datasetVersion":"2026-09-14T05:17:10.506Z"}