Add C++ runtime for spleeter about source separation (#2242)

sherpa-onnx/csrc/offline-source-separation-impl.h

@@ -0,0 +1,35 @@
+// sherpa-onnx/csrc/offline-source-separation-impl.h
+//
+// Copyright (c)  2025  Xiaomi Corporation
+
+#ifndef SHERPA_ONNX_CSRC_OFFLINE_SOURCE_SEPARATION_IMPL_H_
+#define SHERPA_ONNX_CSRC_OFFLINE_SOURCE_SEPARATION_IMPL_H_
+
+#include <vector>
+
+#include "sherpa-onnx/csrc/offline-source-separation.h"
+
+namespace sherpa_onnx {
+
+class OfflineSourceSeparationImpl {
+ public:
+  static std::unique_ptr<OfflineSourceSeparationImpl> Create(
+      const OfflineSourceSeparationConfig &config);
+
+  template <typename Manager>
+  static std::unique_ptr<OfflineSourceSeparationImpl> Create(
+      Manager *mgr, const OfflineSourceSeparationConfig &config);
+
+  virtual ~OfflineSourceSeparationImpl() = default;
+
+  virtual OfflineSourceSeparationOutput Process(
+      const OfflineSourceSeparationInput &input) const = 0;
+
+  virtual int32_t GetOutputSampleRate() const = 0;
+
+  virtual int32_t GetNumberOfStems() const = 0;
+};
+
+}  // namespace sherpa_onnx
+
+#endif  // SHERPA_ONNX_CSRC_OFFLINE_SOURCE_SEPARATION_IMPL_H_