diff --git a/openbsc/src/libmgcp/mgcp_transcode.c b/openbsc/src/libmgcp/mgcp_transcode.c
index a5f71fa..ed5f50b 100644
--- a/openbsc/src/libmgcp/mgcp_transcode.c
+++ b/openbsc/src/libmgcp/mgcp_transcode.c
@@ -22,64 +22,15 @@
 #include <errno.h>
 
 
-#include "../../bscconfig.h"
-
 #include "g711common.h"
-#include <gsm.h>
-#ifdef HAVE_BCG729
-#include <bcg729/decoder.h>
-#include <bcg729/encoder.h>
-#endif
 
 #include <openbsc/debug.h>
 #include <openbsc/mgcp.h>
 #include <openbsc/mgcp_internal.h>
+#include <openbsc/mgcp_transcode.h>
 
 #include <osmocom/core/talloc.h>
 
-enum audio_format {
-	AF_INVALID,
-	AF_S16,
-	AF_L16,
-	AF_GSM,
-	AF_G729,
-	AF_PCMA
-};
-
-struct mgcp_process_rtp_state {
-	/* decoding */
-	enum audio_format src_fmt;
-	union {
-		gsm gsm_handle;
-#ifdef HAVE_BCG729
-		bcg729DecoderChannelContextStruct *g729_dec;
-#endif
-	} src;
-	size_t src_frame_size;
-	size_t src_samples_per_frame;
-
-	/* processing */
-
-	/* encoding */
-	enum audio_format dst_fmt;
-	union {
-		gsm gsm_handle;
-#ifdef HAVE_BCG729
-		bcg729EncoderChannelContextStruct *g729_enc;
-#endif
-	} dst;
-	size_t dst_frame_size;
-	size_t dst_samples_per_frame;
-	int dst_packet_duration;
-
-	int is_running;
-	uint16_t next_seq;
-	uint32_t next_time;
-	int16_t samples[10*160];
-	size_t sample_cnt;
-	size_t sample_offs;
-};
-
 int mgcp_transcoding_get_frame_size(void *state_, int nsamples, int dst)
 {
 	struct mgcp_process_rtp_state *state = state_;