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+/*
+ * liburtc
+ * Copyright (C) 2019 Chris Hiszpanski
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#ifndef URTC_G711_H
+#define URTC_G711_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stddef.h>
+#include <stdint.h>
+
+extern const uint8_t pcm2ulaw[];
+extern const int16_t ulaw2pcm[];
+
+/**
+ * ITU-T G.711 compand a 16-bit signed PCM audio buffer. Buffer may contain
+ * multiple channels, in which case \a n must be the number of frames times
+ * the number of channels.
+ *
+ * Only the upper 13-bits are companded. The lowest 3-bits are discarded.
+ *
+ * \a dst must be allocated and point to at least (\a n / 2) bytes. \a dst
+ * and \a src may overlap.
+ *
+ * @param dst Destination buffer
+ * @param src Signed 16-bit sample source buffer
+ * @param n Number of samples (frames times channels)
+ */
+void g711_encode(uint8_t *dst, const int16_t *src, size_t n);
+
+/**
+ * ITU-T G.711 decompand to a 16-bit signed PCM audio buffer. Buffer may
+ * contain multiple channels, in which case \a n must be the number of frames
+ * times the number of channels.
+ *
+ * The decompanded samples are normalized to 16-bits (the lowest 3-bits will be
+ * zero).
+ *
+ * \a dst must NOT overlap with \a src.
+ *
+ * @param dst Destination buffer
+ * @param src Signed 16-bit sample source buffer
+ * @param n Number of samples (frames times channels)
+ */
+void g711_decode(int16_t *dst, const uint8_t *src, size_t n);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* URTC_G711_H */