Add Silero VAD (#313)

sherpa-onnx/csrc/circular-buffer.h

@@ -0,0 +1,59 @@
+// sherpa-onnx/csrc/circular-buffer.h
+//
+// Copyright (c)  2023  Xiaomi Corporation
+#ifndef SHERPA_ONNX_CSRC_CIRCULAR_BUFFER_H_
+#define SHERPA_ONNX_CSRC_CIRCULAR_BUFFER_H_
+
+#include <cstdint>
+#include <vector>
+
+namespace sherpa_onnx {
+
+class CircularBuffer {
+ public:
+  // Capacity of this buffer. Should be large enough.
+  // If it is full, we just print a message and exit the program.
+  explicit CircularBuffer(int32_t capacity);
+
+  // Push an array
+  //
+  // @param p Pointer to the start address of the array
+  // @param n Number of elements in the array
+  //
+  // Note: If n + Size() > capacity, we print an error message and exit.
+  void Push(const float *p, int32_t n);
+
+  // @param start_index Should in the range [head_, tail_)
+  // @param n Number of elements to get
+  // @return Return a vector of size n containing the requested elements
+  std::vector<float> Get(int32_t start_index, int32_t n) const;
+
+  // Remove n elements from the buffer
+  //
+  // @param n Should be in the range [0, size_]
+  void Pop(int32_t n);
+
+  // Number of elements in the buffer.
+  int32_t Size() const { return tail_ - head_; }
+
+  // Current position of the head
+  int32_t Head() const { return head_; }
+
+  // Current position of the tail
+  int32_t Tail() const { return tail_; }
+
+  void Reset() {
+    head_ = 0;
+    tail_ = 0;
+  }
+
+ private:
+  std::vector<float> buffer_;
+
+  int32_t head_ = 0;  // linear index; always increasing; never wraps around
+  int32_t tail_ = 0;  // linear index, always increasing; never wraps around.
+};
+
+}  // namespace sherpa_onnx
+
+#endif  // SHERPA_ONNX_CSRC_CIRCULAR_BUFFER_H_