Add TORCHCODEC_FFMPEG_DIR to specify FFmpeg dynamic libs search path.

src/torchcodec/_core/ops.py

@@ -103,6 +103,14 @@ def load_torchcodec_shared_libraries() -> tuple[int, str]:
         def expose_ffmpeg_dlls():  # noqa: F811
             ffmpeg_dir = Path(ffmpeg_path).parent
             return os.add_dll_directory(str(ffmpeg_dir))  # that's the actual CM
+
+        if chocolateyInstall := os.environ.get("ChocolateyInstall"):
+            # Chocolatey creates shim so we need to get the actual path to the FFmpeg executable.
+            chocolateyInstallPath = Path(chocolateyInstall)
+            if Path(ffmpeg_path).parent.parent == chocolateyInstallPath and (chocolateyFFmpegSharedPaths := list(chocolateyInstallPath.rglob("lib/ffmpeg-shared/tools/ffmpeg-*-shared/bin"))):
+                chocolateyFFmpegSharedPath = chocolateyFFmpegSharedPaths[0]
+                def expose_ffmpeg_dlls():  # noqa: F811
+                    return os.add_dll_directory(str(chocolateyFFmpegSharedPath))
 
 
 with expose_ffmpeg_dlls():