Silk编解码在android实现

Silk编解码是Skype向第三方开发人员和硬件制造商提供免版税认证(RF)的Silk宽带音频编码器。Skype已将其开源，可以访问 http://developer.skype.com/silk 获取最新动向。SILK Codec是一个语音和音频编解码算法, 对于音频带宽、网络带宽和算法复杂度都具有很好的弹性。支持4种采样率：8KHz、12KHz、16KHz、24KHz；三种复杂度：低、中、高。编码码率在 6~40kbps（不同采样率具有不同的码率范围）以及还支持VAD、DTX、FEC等模块，感觉还是比较全面。最重要的一点是提供了定点C代码，非常有利于向ARM、DSP移植和优化。这一篇主要参考了pjsip中的silk实现。

      1、获取silk源码（http://developer.skype.com/silk）

       2、创建新的android工程，并创建jni文件夹。

       3、将silk源码拷贝到jni目录

       4、在jni目录下新增Android.mk文件，编辑内容如下：

   

 LOCAL_PATH := $(call my-dir)

 include $(CLEAR_VARS)
 SILK     := silk
 LOCAL_MODULE    := silkcommon
 LOCAL_SRC_FILES :=  $(SILK)/src/SKP_Silk_A2NLSF.c \
     $(SILK)/src/SKP_Silk_CNG.c \
     $(SILK)/src/SKP_Silk_HP_variable_cutoff_FIX.c \
     $(SILK)/src/SKP_Silk_LBRR_reset.c \
     $(SILK)/src/SKP_Silk_LPC_inv_pred_gain.c \
     $(SILK)/src/SKP_Silk_LPC_stabilize.c \
     $(SILK)/src/SKP_Silk_LPC_synthesis_filter.c \
     $(SILK)/src/SKP_Silk_LPC_synthesis_order16.c \
     $(SILK)/src/SKP_Silk_LP_variable_cutoff.c \
     $(SILK)/src/SKP_Silk_LSF_cos_table.c \
     $(SILK)/src/SKP_Silk_LTP_analysis_filter_FIX.c \
     $(SILK)/src/SKP_Silk_LTP_scale_ctrl_FIX.c \
     $(SILK)/src/SKP_Silk_MA.c \
     $(SILK)/src/SKP_Silk_NLSF2A.c \
     $(SILK)/src/SKP_Silk_NLSF2A_stable.c \
     $(SILK)/src/SKP_Silk_NLSF_MSVQ_decode.c \
     $(SILK)/src/SKP_Silk_NLSF_MSVQ_encode_FIX.c \
     $(SILK)/src/SKP_Silk_NLSF_VQ_rate_distortion_FIX.c \
     $(SILK)/src/SKP_Silk_NLSF_VQ_sum_error_FIX.c \
     $(SILK)/src/SKP_Silk_NLSF_VQ_weights_laroia.c \
     $(SILK)/src/SKP_Silk_NLSF_stabilize.c \
     $(SILK)/src/SKP_Silk_NSQ.c \
     $(SILK)/src/SKP_Silk_NSQ_del_dec.c \
     $(SILK)/src/SKP_Silk_PLC.c \
     $(SILK)/src/SKP_Silk_VAD.c \
     $(SILK)/src/SKP_Silk_VQ_nearest_neighbor_FIX.c \
     $(SILK)/src/SKP_Silk_allpass_int.c \
     $(SILK)/src/SKP_Silk_ana_filt_bank_1.c \
     $(SILK)/src/SKP_Silk_apply_sine_window.c \
     $(SILK)/src/SKP_Silk_array_maxabs.c \
     $(SILK)/src/SKP_Silk_autocorr.c \
     $(SILK)/src/SKP_Silk_biquad.c \
     $(SILK)/src/SKP_Silk_biquad_alt.c \
     $(SILK)/src/SKP_Silk_burg_modified.c \
     $(SILK)/src/SKP_Silk_bwexpander.c \
     $(SILK)/src/SKP_Silk_bwexpander_32.c \
     $(SILK)/src/SKP_Silk_code_signs.c \
     $(SILK)/src/SKP_Silk_control_codec_FIX.c \
     $(SILK)/src/SKP_Silk_corrMatrix_FIX.c \
     $(SILK)/src/SKP_Silk_create_init_destroy.c \
     $(SILK)/src/SKP_Silk_dec_API.c \
     $(SILK)/src/SKP_Silk_decode_core.c \
     $(SILK)/src/SKP_Silk_decode_frame.c \
     $(SILK)/src/SKP_Silk_decode_indices_v4.c \
     $(SILK)/src/SKP_Silk_decode_parameters.c \
     $(SILK)/src/SKP_Silk_decode_parameters_v4.c \
     $(SILK)/src/SKP_Silk_decode_pulses.c \
     $(SILK)/src/SKP_Silk_decoder_set_fs.c \
     $(SILK)/src/SKP_Silk_detect_SWB_input.c \
     $(SILK)/src/SKP_Silk_enc_API.c \
     $(SILK)/src/SKP_Silk_encode_frame_FIX.c \
     $(SILK)/src/SKP_Silk_encode_parameters.c \
     $(SILK)/src/SKP_Silk_encode_parameters_v4.c \
     $(SILK)/src/SKP_Silk_encode_pulses.c \
     $(SILK)/src/SKP_Silk_find_LPC_FIX.c \
     $(SILK)/src/SKP_Silk_find_LTP_FIX.c \
     $(SILK)/src/SKP_Silk_find_pitch_lags_FIX.c \
     $(SILK)/src/SKP_Silk_find_pred_coefs_FIX.c \
     $(SILK)/src/SKP_Silk_gain_quant.c \
     $(SILK)/src/SKP_Silk_init_encoder_FIX.c \
     $(SILK)/src/SKP_Silk_inner_prod_aligned.c \
     $(SILK)/src/SKP_Silk_interpolate.c \
     $(SILK)/src/SKP_Silk_k2a.c \
     $(SILK)/src/SKP_Silk_k2a_Q16.c \
     $(SILK)/src/SKP_Silk_lin2log.c \
     $(SILK)/src/SKP_Silk_log2lin.c \
     $(SILK)/src/SKP_Silk_lowpass_int.c \
     $(SILK)/src/SKP_Silk_lowpass_short.c \
     $(SILK)/src/SKP_Silk_noise_shape_analysis_FIX.c \
     $(SILK)/src/SKP_Silk_pitch_analysis_core.c \
     $(SILK)/src/SKP_Silk_pitch_est_tables.c \
     $(SILK)/src/SKP_Silk_prefilter_FIX.c \
     $(SILK)/src/SKP_Silk_process_NLSFs_FIX.c \
     $(SILK)/src/SKP_Silk_process_gains_FIX.c \
     $(SILK)/src/SKP_Silk_pulses_to_bytes.c \
     $(SILK)/src/SKP_Silk_quant_LTP_gains_FIX.c \
     $(SILK)/src/SKP_Silk_range_coder.c \
     $(SILK)/src/SKP_Silk_regularize_correlations_FIX.c \
     $(SILK)/src/SKP_Silk_resample_1_2.c \
     $(SILK)/src/SKP_Silk_resample_1_2_coarse.c \
     $(SILK)/src/SKP_Silk_resample_1_2_coarsest.c \
     $(SILK)/src/SKP_Silk_resample_1_3.c \
     $(SILK)/src/SKP_Silk_resample_2_1_coarse.c \
     $(SILK)/src/SKP_Silk_resample_2_3.c \
     $(SILK)/src/SKP_Silk_resample_2_3_coarse.c \
     $(SILK)/src/SKP_Silk_resample_2_3_coarsest.c \
     $(SILK)/src/SKP_Silk_resample_2_3_rom.c \
     $(SILK)/src/SKP_Silk_resample_3_1.c \
     $(SILK)/src/SKP_Silk_resample_3_2.c \
     $(SILK)/src/SKP_Silk_resample_3_2_rom.c \
     $(SILK)/src/SKP_Silk_resample_3_4.c \
     $(SILK)/src/SKP_Silk_resample_4_3.c \
     $(SILK)/src/SKP_Silk_residual_energy16_FIX.c \
     $(SILK)/src/SKP_Silk_residual_energy_FIX.c \
     $(SILK)/src/SKP_Silk_scale_copy_vector16.c \
     $(SILK)/src/SKP_Silk_scale_vector.c \
     $(SILK)/src/SKP_Silk_schur.c \
     $(SILK)/src/SKP_Silk_schur64.c \
     $(SILK)/src/SKP_Silk_shell_coder.c \
     $(SILK)/src/SKP_Silk_sigm_Q15.c \
     $(SILK)/src/SKP_Silk_solve_LS_FIX.c \
     $(SILK)/src/SKP_Silk_sort.c \
     $(SILK)/src/SKP_Silk_sum_sqr_shift.c \
     $(SILK)/src/SKP_Silk_tables_LTP.c \
     $(SILK)/src/SKP_Silk_tables_NLSF_CB0_10.c \
     $(SILK)/src/SKP_Silk_tables_NLSF_CB0_16.c \
     $(SILK)/src/SKP_Silk_tables_NLSF_CB1_10.c \
     $(SILK)/src/SKP_Silk_tables_NLSF_CB1_16.c \
     $(SILK)/src/SKP_Silk_tables_gain.c \
     $(SILK)/src/SKP_Silk_tables_other.c \
     $(SILK)/src/SKP_Silk_tables_pitch_lag.c \
     $(SILK)/src/SKP_Silk_tables_pulses_per_block.c \
     $(SILK)/src/SKP_Silk_tables_sign.c \
     $(SILK)/src/SKP_Silk_tables_type_offset.c

 LOCAL_ARM_MODE := arm
 LOCAL_CFLAGS = -O3
 LOCAL_LDLIBS := -L$(SYSROOT)/usr/lib -llog
 LOCAL_C_INCLUDES += $(LOCAL_PATH)/$(SILK)/src $(LOCAL_PATH)/$(SILK)/interface
 include $(BUILD_STATIC_LIBRARY)


 include $(CLEAR_VARS)
 LOCAL_MODULE    := silk8_jni
 LOCAL_SRC_FILES := silk8_jni.cpp
 LOCAL_C_INCLUDES += $(LOCAL_PATH)/$(SILK)/src $(LOCAL_PATH)/$(SILK)/interface
 LOCAL_CFLAGS = -O3
 LOCAL_STATIC_LIBRARIES :=  silkcommon
 LOCAL_ARM_MODE := arm
 LOCAL_LDLIBS := -L$(SYSROOT)/usr/lib -llog
 include $(BUILD_SHARED_LIBRARY)

 include $(CLEAR_VARS)
 LOCAL_MODULE    := silk16_jni
 LOCAL_SRC_FILES := silk16_jni.cpp
 LOCAL_C_INCLUDES += $(LOCAL_PATH)/$(SILK)/src $(LOCAL_PATH)/$(SILK)/interface
 LOCAL_CFLAGS = -O3
 LOCAL_STATIC_LIBRARIES :=  silkcommon
 LOCAL_ARM_MODE := arm
 LOCAL_LDLIBS := -L$(SYSROOT)/usr/lib -llog
 include $(BUILD_SHARED_LIBRARY)

 include $(CLEAR_VARS)
 LOCAL_MODULE    := silk24_jni
 LOCAL_SRC_FILES := silk24_jni.cpp
 LOCAL_C_INCLUDES += $(LOCAL_PATH)/$(SILK)/src $(LOCAL_PATH)/$(SILK)/interface
 LOCAL_CFLAGS = -O3
 LOCAL_STATIC_LIBRARIES :=  silkcommon
 LOCAL_ARM_MODE := arm
 LOCAL_LDLIBS := -L$(SYSROOT)/usr/lib -llog
 include $(BUILD_SHARED_LIBRARY)

       5、创建JNI包装类silk8_jni.cpp、silk16_jni.cpp、silk24_jni.cpp，用来调用Silk中的C代码函数，编辑内容如下

      silk8_jni.cpp:

    

 #include <jni.h>

 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <math.h>

 /* Define codec specific settings */
 #define MAX_BYTES_ENC_PER_FRAME     250 // Equals peak bitrate of 100 kbps
 #define MAX_BYTES_DEC_PER_FRAME     1024

 #define MAX_INPUT_FRAMES        5
 #define MAX_LBRR_DELAY          2
 #define MAX_FRAME_LENGTH        480

 #define MAX_FRAME           160

 #include <android/log.h>

 #define LOG_TAG "silk" // text for log tag

 #include "SKP_Silk_SDK_API.h"
 #include "SKP_Silk_SigProc_FIX.h"

 #undef DEBUG_SILK8

 // the header length of the RTP frame (must skip when en/decoding)
 #define RTP_HDR_SIZE    12

 static int codec_open = 0;

 static JavaVM *gJavaVM;
 const char *kInterfacePath = "org/sipdroid/pjlib/silk8";

 /* encoder parameters */

     SKP_int32 encSizeBytes;
     void      *psEnc;

     /* default settings */
     SKP_int   fs_kHz = 8;
     SKP_int   targetRate_bps = 20000;
     SKP_int   packetSize_ms = 20;
     SKP_int   frameSizeReadFromFile_ms = 20;
     SKP_int   packetLoss_perc = 0, smplsSinceLastPacket;
     SKP_int   INBandFec_enabled = 0, DTX_enabled = 0, quiet = 0;
     SKP_SILK_SDK_EncControlStruct encControl; // Struct for input to encoder


 /* decoder parameters */

     jbyte payloadToDec[    MAX_BYTES_DEC_PER_FRAME * MAX_INPUT_FRAMES * ( MAX_LBRR_DELAY + 1 ) ];
     jshort out[ ( MAX_FRAME_LENGTH << 1 ) * MAX_INPUT_FRAMES ], *outPtr;
     SKP_int32 decSizeBytes;
     void      *psDec;
     SKP_SILK_SDK_DecControlStruct DecControl;

 extern "C"
 JNIEXPORT jint JNICALL Java_com_trunkbow_silk_SILK8_open
   (JNIEnv *env, jobject obj, jint compression) {
     int ret;

     if (codec_open++ != 0)
         return (jint)0;

     /* Set the samplingrate that is requested for the output */
     DecControl.sampleRate = 8000;

     /* Create decoder */
     ret = SKP_Silk_SDK_Get_Decoder_Size( &decSizeBytes );
     if( ret ) {
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "\n!!!!!!!! SKP_Silk_SDK_Get_Decoder_Size returned %d", ret );
     }
 #ifdef DEBUG_SILK8
     __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "### INIT Decoder decSizeBytes = %d\n", decSizeBytes);
 #endif
     psDec = malloc( decSizeBytes );

     /* Reset decoder */
     ret = SKP_Silk_SDK_InitDecoder( psDec );
     if( ret ) {
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "\n!!!!!!!! SKP_Silk_InitDecoder returned %d", ret );
     }


     /* Create Encoder */
     ret = SKP_Silk_SDK_Get_Encoder_Size( &encSizeBytes );
     if( ret ) {
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "\n!!!!!!!! SKP_Silk_SDK_Get_Encoder_Size returned %d", ret );
     }
 #ifdef DEBUG_SILK8
     __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "### INIT Encoder encSizeBytes = %d\n", encSizeBytes);
 #endif
     psEnc = malloc( encSizeBytes );

     /* Reset Encoder */
     ret = SKP_Silk_SDK_InitEncoder( psEnc, &encControl );
     if( ret ) {
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "\n!!!!!!!! SKP_Silk_SDK_InitEncoder returned %d", ret );
     }

     /* Set Encoder parameters */
     encControl.sampleRate           = fs_kHz * 1000;
     encControl.packetSize           = packetSize_ms * fs_kHz;
     encControl.packetLossPercentage = packetLoss_perc;
     encControl.useInBandFEC         = INBandFec_enabled;
     encControl.useDTX               = DTX_enabled;
     encControl.complexity           = compression;
     encControl.bitRate              = targetRate_bps;

     return (jint)0;
 }

 void Print_Decode_Error_Msg(int errcode) {
     switch (errcode) {
         case SKP_SILK_DEC_WRONG_SAMPLING_FREQUENCY:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nOutput sampling frequency lower than internal decoded sampling frequency\n", errcode);
             break;
         case SKP_SILK_DEC_PAYLOAD_TOO_LARGE:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nPayload size exceeded the maximum allowed 1024 bytes\n", errcode);
             break;
         case SKP_SILK_DEC_PAYLOAD_ERROR:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nPayload has bit errors\n", errcode);
             break;
     }
 }

 void Print_Encode_Error_Msg(int errcode) {
     switch (errcode) {
         case SKP_SILK_ENC_INPUT_INVALID_NO_OF_SAMPLES:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nInput length is not a multiplum of 10 ms, or length is longer than the packet length\n", errcode);
             break;
         case SKP_SILK_ENC_FS_NOT_SUPPORTED:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nSampling frequency not 8000, 12000, 16000 or 24000 Hertz \n", errcode);
             break;
         case SKP_SILK_ENC_PACKET_SIZE_NOT_SUPPORTED:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nPacket size not 20, 40, 60, 80 or 100 ms\n", errcode);
             break;
         case SKP_SILK_ENC_PAYLOAD_BUF_TOO_SHORT:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nAllocated payload buffer too short \n", errcode);
             break;
         case SKP_SILK_ENC_WRONG_LOSS_RATE:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nLoss rate not between 0 and 100 percent\n", errcode);
             break;
         case SKP_SILK_ENC_WRONG_COMPLEXITY_SETTING:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nComplexity setting not valid, use 0, 1 or 2\n", errcode);
             break;
         case SKP_SILK_ENC_WRONG_INBAND_FEC_SETTING:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nInband FEC setting not valid, use 0 or 1\n", errcode);
             break;
         case SKP_SILK_ENC_WRONG_DTX_SETTING:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nDTX setting not valid, use 0 or 1\n", errcode);
             break;
         case SKP_SILK_ENC_INTERNAL_ERROR:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nInternal encoder error\n", errcode);
             break;
     }
 }

 extern "C"
 JNIEXPORT jint JNICALL Java_com_trunkbow_silk_SILK8_encode
     (JNIEnv *env, jobject obj, jshortArray lin, jint offset, jbyteArray encoded, jint size) {

     jbyte     enc_payload[ MAX_BYTES_DEC_PER_FRAME * MAX_INPUT_FRAMES ];
     jshort    in[ MAX_FRAME_LENGTH * MAX_INPUT_FRAMES ];
     int ret,i,frsz=MAX_FRAME;
     SKP_int16 nBytes;
     unsigned int lin_pos = 0;

     if (!codec_open)
         return 0;

 #ifdef DEBUG_SILK8
     __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "encoding frame size: %d\toffset: %d\n", size, offset);
 #endif


     for (i = 0; i < size; i+=MAX_FRAME) {
 #ifdef DEBUG_SILK8
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "encoding frame size: %d\toffset: %d i: %d\n", size, offset, i);
 #endif

         env->GetShortArrayRegion(lin, offset + i,frsz, in);
         /* max payload size */
         nBytes = MAX_BYTES_ENC_PER_FRAME * MAX_INPUT_FRAMES;

         ret = SKP_Silk_SDK_Encode( psEnc, &encControl, in, (SKP_int16)frsz, (SKP_uint8 *)enc_payload, &nBytes );
         if( ret ) {
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!! SKP_Silk_Encode returned: %d\n", ret);
             Print_Encode_Error_Msg(ret);
             break;
         }
 #ifdef DEBUG_SILK8
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "Enocded nBytes: %d\n", nBytes);
 #endif
         /* Write payload */
         env->SetByteArrayRegion(encoded, RTP_HDR_SIZE+ lin_pos, nBytes, enc_payload);
         lin_pos += nBytes;
     }
 #ifdef DEBUG_SILK8
     __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
         "encoding **END** frame size: %d\toffset: %d i: %d lin_pos: %d\n", size, offset, i, lin_pos);
 #endif

     return (jint)lin_pos;
 }

 extern "C"
 JNIEXPORT jint JNICALL Java_com_trunkbow_silk_SILK8_decode
     (JNIEnv *env, jobject obj, jbyteArray encoded, jshortArray lin, jint size) {

     jbyte buffer [MAX_BYTES_DEC_PER_FRAME * MAX_INPUT_FRAMES * ( MAX_LBRR_DELAY + 1 ) ];
     jshort output_buffer[( MAX_FRAME_LENGTH << 1 ) * MAX_INPUT_FRAMES ];
 //  SKP_int16   *outPtr;

     int ret;
     SKP_int16 len;
 //  int tot_len,frames;

     if (!codec_open)
         return 0;

 #ifdef DEBUG_SILK8
     __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
         "##### BEGIN DECODE ********  decoding frame size: %d\n", size);
 #endif

     env->GetByteArrayRegion(encoded, RTP_HDR_SIZE, size, buffer);

 //  outPtr = output_buffer;
 //    tot_len = 0;
 //  frames = 0;

 //  do {
         ret = SKP_Silk_SDK_Decode( psDec, &DecControl, 0,(SKP_uint8 *) buffer, size, output_buffer,&len );
         if( ret ) {
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!! SKP_Silk_SDK_Decode returned: %d\n", ret);
             Print_Decode_Error_Msg(ret);
         }
 #ifdef DEBUG_SILK8
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "##### DECODED length: %d\n\t Frame #: %d", len);
 #endif
 //      frames++;
 //      outPtr  += len;
 //      tot_len += len;

 //  } while( DecControl.moreInternalDecoderFrames );

     env->SetShortArrayRegion(lin, 0, len,output_buffer);
     return (jint)len;
 }

 extern "C"
 JNIEXPORT void JNICALL Java_com_trunkbow_silk_SILK8_close
     (JNIEnv *env, jobject obj) {

     if (--codec_open != 0)
         return;
     /* Free decoder */
     free( psDec );
     /* Free Encoder */
     free( psEnc );
 }

      silk_16.cpp:

      

 #include <jni.h>

 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <math.h>

 /* Define codec specific settings */
 #define MAX_BYTES_ENC_PER_FRAME     250 // Equals peak bitrate of 100 kbps
 #define MAX_BYTES_DEC_PER_FRAME     1024

 #define MAX_INPUT_FRAMES        5
 #define MAX_LBRR_DELAY          2
 #define MAX_FRAME_LENGTH        480

 #define MAX_FRAME           320

 #include <android/log.h>

 #define LOG_TAG "silk" // text for log tag

 #include "SKP_Silk_SDK_API.h"
 #include "SKP_Silk_SigProc_FIX.h"

 #undef DEBUG_SILK16

 // the header length of the RTP frame (must skip when en/decoding)
 #define RTP_HDR_SIZE    12

 static int codec_open = 0;

 static JavaVM *gJavaVM;
 const char *kInterfacePath = "org/sipdroid/pjlib/silk16";

 /* encoder parameters */

     SKP_int32 encSizeBytes;
     void      *psEnc;

     /* default settings */
     SKP_int   fs_kHz = 16;
     SKP_int   targetRate_bps = 20000;
     SKP_int   packetSize_ms = 20;
     SKP_int   frameSizeReadFromFile_ms = 20;
     SKP_int   packetLoss_perc = 0, smplsSinceLastPacket;
     SKP_int   INBandFec_enabled = 0, DTX_enabled = 0, quiet = 0;
     SKP_SILK_SDK_EncControlStruct encControl; // Struct for input to encoder


 /* decoder parameters */

     jbyte payloadToDec[    MAX_BYTES_DEC_PER_FRAME * MAX_INPUT_FRAMES * ( MAX_LBRR_DELAY + 1 ) ];
     jshort out[ ( MAX_FRAME_LENGTH << 1 ) * MAX_INPUT_FRAMES ], *outPtr;
     SKP_int32 decSizeBytes;
     void      *psDec;
     SKP_SILK_SDK_DecControlStruct DecControl;

 extern "C"
 JNIEXPORT jint JNICALL Java_com_trunkbow_silk_SILK16_open
   (JNIEnv *env, jobject obj, jint compression) {
     int ret;

     if (codec_open++ != 0)
         return (jint)0;

     /* Set the samplingrate that is requested for the output */
     DecControl.sampleRate = 16000;

     /* Create decoder */
     ret = SKP_Silk_SDK_Get_Decoder_Size( &decSizeBytes );
     if( ret ) {
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "\n!!!!!!!! SKP_Silk_SDK_Get_Decoder_Size returned %d", ret );
     }
 #ifdef DEBUG_SILK16
     __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "### INIT Decoder decSizeBytes = %d\n", decSizeBytes);
 #endif
     psDec = malloc( decSizeBytes );

     /* Reset decoder */
     ret = SKP_Silk_SDK_InitDecoder( psDec );
     if( ret ) {
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "\n!!!!!!!! SKP_Silk_InitDecoder returned %d", ret );
     }


     /* Create Encoder */
     ret = SKP_Silk_SDK_Get_Encoder_Size( &encSizeBytes );
     if( ret ) {
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "\n!!!!!!!! SKP_Silk_SDK_Get_Encoder_Size returned %d", ret );
     }
 #ifdef DEBUG_SILK16
     __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "### INIT Encoder encSizeBytes = %d\n", encSizeBytes);
 #endif
     psEnc = malloc( encSizeBytes );

     /* Reset Encoder */
     ret = SKP_Silk_SDK_InitEncoder( psEnc, &encControl );
     if( ret ) {
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "\n!!!!!!!! SKP_Silk_SDK_InitEncoder returned %d", ret );
     }

     /* Set Encoder parameters */
     encControl.sampleRate           = fs_kHz * 1000;
     encControl.packetSize           = packetSize_ms * fs_kHz;
     encControl.packetLossPercentage = packetLoss_perc;
     encControl.useInBandFEC         = INBandFec_enabled;
     encControl.useDTX               = DTX_enabled;
     encControl.complexity           = compression;
     encControl.bitRate              = targetRate_bps;

     return (jint)0;
 }

 void Print_Decode_Error_Msg(int errcode) {
     switch (errcode) {
         case SKP_SILK_DEC_WRONG_SAMPLING_FREQUENCY:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nOutput sampling frequency lower than internal decoded sampling frequency\n", errcode);
             break;
         case SKP_SILK_DEC_PAYLOAD_TOO_LARGE:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nPayload size exceeded the maximum allowed 1024 bytes\n", errcode);
             break;
         case SKP_SILK_DEC_PAYLOAD_ERROR:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nPayload has bit errors\n", errcode);
             break;
     }
 }

 void Print_Encode_Error_Msg(int errcode) {
     switch (errcode) {
         case SKP_SILK_ENC_INPUT_INVALID_NO_OF_SAMPLES:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nInput length is not a multiplum of 10 ms, or length is longer than the packet length\n", errcode);
             break;
         case SKP_SILK_ENC_FS_NOT_SUPPORTED:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nSampling frequency not 8000, 12000, 16000 or 24000 Hertz \n", errcode);
             break;
         case SKP_SILK_ENC_PACKET_SIZE_NOT_SUPPORTED:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nPacket size not 20, 40, 60, 80 or 100 ms\n", errcode);
             break;
         case SKP_SILK_ENC_PAYLOAD_BUF_TOO_SHORT:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nAllocated payload buffer too short \n", errcode);
             break;
         case SKP_SILK_ENC_WRONG_LOSS_RATE:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nLoss rate not between 0 and 100 percent\n", errcode);
             break;
         case SKP_SILK_ENC_WRONG_COMPLEXITY_SETTING:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nComplexity setting not valid, use 0, 1 or 2\n", errcode);
             break;
         case SKP_SILK_ENC_WRONG_INBAND_FEC_SETTING:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nInband FEC setting not valid, use 0 or 1\n", errcode);
             break;
         case SKP_SILK_ENC_WRONG_DTX_SETTING:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nDTX setting not valid, use 0 or 1\n", errcode);
             break;
         case SKP_SILK_ENC_INTERNAL_ERROR:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nInternal encoder error\n", errcode);
             break;
     }
 }

 extern "C"
 JNIEXPORT jint JNICALL Java_com_trunkbow_silk_SILK16_encode
     (JNIEnv *env, jobject obj, jshortArray lin, jint offset, jbyteArray encoded, jint size) {

     jbyte     enc_payload[ MAX_BYTES_DEC_PER_FRAME * MAX_INPUT_FRAMES ];
     jshort    in[ MAX_FRAME_LENGTH * MAX_INPUT_FRAMES ];
     int ret,i,frsz=MAX_FRAME;
     SKP_int16 nBytes;
     unsigned int lin_pos = 0;

     if (!codec_open)
         return 0;

 #ifdef DEBUG_SILK16
     __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "encoding frame size: %d\toffset: %d\n", size, offset);
 #endif


     for (i = 0; i < size; i+=MAX_FRAME) {
 #ifdef DEBUG_SILK16
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "encoding frame size: %d\toffset: %d i: %d\n", size, offset, i);
 #endif

         env->GetShortArrayRegion(lin, offset + i,frsz, in);
         /* max payload size */
         nBytes = MAX_BYTES_ENC_PER_FRAME * MAX_INPUT_FRAMES;

         ret = SKP_Silk_SDK_Encode( psEnc, &encControl, in, (SKP_int16)frsz, (SKP_uint8 *)enc_payload, &nBytes );
         if( ret ) {
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!! SKP_Silk_Encode returned: %d\n", ret);
             Print_Encode_Error_Msg(ret);
             break;
         }
 #ifdef DEBUG_SILK16
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "Enocded nBytes: %d\n", nBytes);
 #endif
         /* Write payload */
         env->SetByteArrayRegion(encoded, RTP_HDR_SIZE+ lin_pos, nBytes, enc_payload);
         lin_pos += nBytes;
     }
 #ifdef DEBUG_SILK16
     __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
         "encoding **END** frame size: %d\toffset: %d i: %d lin_pos: %d\n", size, offset, i, lin_pos);
 #endif

     return (jint)lin_pos;
 }

 extern "C"
 JNIEXPORT jint JNICALL Java_com_trunkbow_silk_SILK16_decode
     (JNIEnv *env, jobject obj, jbyteArray encoded, jshortArray lin, jint size) {

     jbyte buffer [MAX_BYTES_DEC_PER_FRAME * MAX_INPUT_FRAMES * ( MAX_LBRR_DELAY + 1 ) ];
     jshort output_buffer[( MAX_FRAME_LENGTH << 1 ) * MAX_INPUT_FRAMES ];
 //  SKP_int16   *outPtr;

     int ret;
     SKP_int16 len;
 //  int tot_len,frames;

     if (!codec_open)
         return 0;

 #ifdef DEBUG_SILK16
     __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
         "##### BEGIN DECODE ********  decoding frame size: %d\n", size);
 #endif

     env->GetByteArrayRegion(encoded, RTP_HDR_SIZE, size, buffer);

 //  outPtr = output_buffer;
 //    tot_len = 0;
 //  frames = 0;

 //  do {
         ret = SKP_Silk_SDK_Decode( psDec, &DecControl, 0,(SKP_uint8 *) buffer, size, output_buffer,&len );
         if( ret ) {
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!! SKP_Silk_SDK_Decode returned: %d\n", ret);
             Print_Decode_Error_Msg(ret);
         }
 #ifdef DEBUG_SILK16
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "##### DECODED length: %d\n\t Frame #: %d", len);
 #endif
 //      frames++;
 //      outPtr  += len;
 //      tot_len += len;

 //  } while( DecControl.moreInternalDecoderFrames );

     env->SetShortArrayRegion(lin, 0, len,output_buffer);
     return (jint)len;
 }

 extern "C"
 JNIEXPORT void JNICALL Java_com_trunkbow_silk_SILK16_close
     (JNIEnv *env, jobject obj) {

     if (--codec_open != 0)
         return;
     /* Free decoder */
     free( psDec );
     /* Free Encoder */
     free( psEnc );
 }

         silk24_jni.cpp

        

 #include <jni.h>

 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <math.h>

 /* Define codec specific settings */
 #define MAX_BYTES_ENC_PER_FRAME     250 // Equals peak bitrate of 100 kbps
 #define MAX_BYTES_DEC_PER_FRAME     1024

 #define MAX_INPUT_FRAMES        5
 #define MAX_LBRR_DELAY          2
 #define MAX_FRAME_LENGTH        480

 #define MAX_FRAME           480

 #include <android/log.h>

 #define LOG_TAG "silk" // text for log tag

 #include "SKP_Silk_SDK_API.h"
 #include "SKP_Silk_SigProc_FIX.h"

 #undef DEBUG_SILK24

 // the header length of the RTP frame (must skip when en/decoding)
 #define RTP_HDR_SIZE    12

 static int codec_open = 0;

 static JavaVM *gJavaVM;
 const char *kInterfacePath = "org/sipdroid/pjlib/SILK24";

 /* encoder parameters */

     SKP_int32 encSizeBytes;
     void      *psEnc;

     /* default settings */
     SKP_int   fs_kHz = 24;
     SKP_int   targetRate_bps = 20000;
     SKP_int   packetSize_ms = 20;
     SKP_int   frameSizeReadFromFile_ms = 20;
     SKP_int   packetLoss_perc = 0, smplsSinceLastPacket;
     SKP_int   INBandFec_enabled = 0, DTX_enabled = 0, quiet = 0;
     SKP_SILK_SDK_EncControlStruct encControl; // Struct for input to encoder


 /* decoder parameters */

     jbyte payloadToDec[    MAX_BYTES_DEC_PER_FRAME * MAX_INPUT_FRAMES * ( MAX_LBRR_DELAY + 1 ) ];
     jshort out[ ( MAX_FRAME_LENGTH << 1 ) * MAX_INPUT_FRAMES ], *outPtr;
     SKP_int32 decSizeBytes;
     void      *psDec;
     SKP_SILK_SDK_DecControlStruct DecControl;

 extern "C"
 JNIEXPORT jint JNICALL Java_com_trunkbow_silk_SILK24_open
   (JNIEnv *env, jobject obj, jint compression) {
     int ret;

     if (codec_open++ != 0)
         return (jint)0;

     /* Set the samplingrate that is requested for the output */
     DecControl.sampleRate = 24000;

     /* Create decoder */
     ret = SKP_Silk_SDK_Get_Decoder_Size( &decSizeBytes );
     if( ret ) {
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "\n!!!!!!!! SKP_Silk_SDK_Get_Decoder_Size returned %d", ret );
     }
 #ifdef DEBUG_SILK24
     __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "### INIT Decoder decSizeBytes = %d\n", decSizeBytes);
 #endif
     psDec = malloc( decSizeBytes );

     /* Reset decoder */
     ret = SKP_Silk_SDK_InitDecoder( psDec );
     if( ret ) {
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "\n!!!!!!!! SKP_Silk_InitDecoder returned %d", ret );
     }


     /* Create Encoder */
     ret = SKP_Silk_SDK_Get_Encoder_Size( &encSizeBytes );
     if( ret ) {
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "\n!!!!!!!! SKP_Silk_SDK_Get_Encoder_Size returned %d", ret );
     }
 #ifdef DEBUG_SILK24
     __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "### INIT Encoder encSizeBytes = %d\n", encSizeBytes);
 #endif
     psEnc = malloc( encSizeBytes );

     /* Reset Encoder */
     ret = SKP_Silk_SDK_InitEncoder( psEnc, &encControl );
     if( ret ) {
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "\n!!!!!!!! SKP_Silk_SDK_InitEncoder returned %d", ret );
     }

     /* Set Encoder parameters */
     encControl.sampleRate           = fs_kHz * 1000;
     encControl.packetSize           = packetSize_ms * fs_kHz;
     encControl.packetLossPercentage = packetLoss_perc;
     encControl.useInBandFEC         = INBandFec_enabled;
     encControl.useDTX               = DTX_enabled;
     encControl.complexity           = compression;
     encControl.bitRate              = targetRate_bps;

     return (jint)0;
 }

 void Print_Decode_Error_Msg(int errcode) {
     switch (errcode) {
         case SKP_SILK_DEC_WRONG_SAMPLING_FREQUENCY:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nOutput sampling frequency lower than internal decoded sampling frequency\n", errcode);
             break;
         case SKP_SILK_DEC_PAYLOAD_TOO_LARGE:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nPayload size exceeded the maximum allowed 1024 bytes\n", errcode);
             break;
         case SKP_SILK_DEC_PAYLOAD_ERROR:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nPayload has bit errors\n", errcode);
             break;
     }
 }

 void Print_Encode_Error_Msg(int errcode) {
     switch (errcode) {
         case SKP_SILK_ENC_INPUT_INVALID_NO_OF_SAMPLES:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nInput length is not a multiplum of 10 ms, or length is longer than the packet length\n", errcode);
             break;
         case SKP_SILK_ENC_FS_NOT_SUPPORTED:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nSampling frequency not 8000, 12000, 16000 or 24000 Hertz \n", errcode);
             break;
         case SKP_SILK_ENC_PACKET_SIZE_NOT_SUPPORTED:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nPacket size not 20, 40, 60, 80 or 100 ms\n", errcode);
             break;
         case SKP_SILK_ENC_PAYLOAD_BUF_TOO_SHORT:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nAllocated payload buffer too short \n", errcode);
             break;
         case SKP_SILK_ENC_WRONG_LOSS_RATE:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nLoss rate not between 0 and 100 percent\n", errcode);
             break;
         case SKP_SILK_ENC_WRONG_COMPLEXITY_SETTING:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nComplexity setting not valid, use 0, 1 or 2\n", errcode);
             break;
         case SKP_SILK_ENC_WRONG_INBAND_FEC_SETTING:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nInband FEC setting not valid, use 0 or 1\n", errcode);
             break;
         case SKP_SILK_ENC_WRONG_DTX_SETTING:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nDTX setting not valid, use 0 or 1\n", errcode);
             break;
         case SKP_SILK_ENC_INTERNAL_ERROR:
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!!!!! Decode_Error_Message: %d\nInternal encoder error\n", errcode);
             break;
     }
 }

 extern "C"
 JNIEXPORT jint JNICALL Java_com_trunkbow_silk_SILK24_encode
     (JNIEnv *env, jobject obj, jshortArray lin, jint offset, jbyteArray encoded, jint size) {

     jbyte     enc_payload[ MAX_BYTES_DEC_PER_FRAME * MAX_INPUT_FRAMES ];
     jshort    in[ MAX_FRAME_LENGTH * MAX_INPUT_FRAMES ];
     int ret,i,frsz=MAX_FRAME;
     SKP_int16 nBytes;
     unsigned int lin_pos = 0;

     if (!codec_open)
         return 0;

 #ifdef DEBUG_SILK24
     __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "encoding frame size: %d\toffset: %d\n", size, offset);
 #endif


     for (i = 0; i < size; i+=MAX_FRAME) {
 #ifdef DEBUG_SILK24
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "encoding frame size: %d\toffset: %d i: %d\n", size, offset, i);
 #endif

         env->GetShortArrayRegion(lin, offset + i,frsz, in);
         /* max payload size */
         nBytes = MAX_BYTES_ENC_PER_FRAME * MAX_INPUT_FRAMES;

         ret = SKP_Silk_SDK_Encode( psEnc, &encControl, in, (SKP_int16)frsz, (SKP_uint8 *)enc_payload, &nBytes );
         if( ret ) {
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!! SKP_Silk_Encode returned: %d\n", ret);
             Print_Encode_Error_Msg(ret);
             break;
         }
 #ifdef DEBUG_SILK24
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "Enocded nBytes: %d\n", nBytes);
 #endif
         /* Write payload */
         env->SetByteArrayRegion(encoded, RTP_HDR_SIZE+ lin_pos, nBytes, enc_payload);
         lin_pos += nBytes;
     }
 #ifdef DEBUG_SILK24
     __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
         "encoding **END** frame size: %d\toffset: %d i: %d lin_pos: %d\n", size, offset, i, lin_pos);
 #endif

     return (jint)lin_pos;
 }

 extern "C"
 JNIEXPORT jint JNICALL Java_com_trunkbow_silk_SILK24_decode
     (JNIEnv *env, jobject obj, jbyteArray encoded, jshortArray lin, jint size) {

     jbyte buffer [MAX_BYTES_DEC_PER_FRAME * MAX_INPUT_FRAMES * ( MAX_LBRR_DELAY + 1 ) ];
     jshort output_buffer[( MAX_FRAME_LENGTH << 1 ) * MAX_INPUT_FRAMES ];
 //  SKP_int16   *outPtr;

     int ret;
     SKP_int16 len;
 //  int tot_len,frames;

     if (!codec_open)
         return 0;

 #ifdef DEBUG_SILK24
     __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
         "##### BEGIN DECODE ********  decoding frame size: %d\n", size);
 #endif

     env->GetByteArrayRegion(encoded, RTP_HDR_SIZE, size, buffer);

 //  outPtr = output_buffer;
 //    tot_len = 0;
 //  frames = 0;

 //  do {
         ret = SKP_Silk_SDK_Decode( psDec, &DecControl, 0,(SKP_uint8 *) buffer, size, output_buffer,&len );
         if( ret ) {
             __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
                 "!!!!!!!! SKP_Silk_SDK_Decode returned: %d\n", ret);
             Print_Decode_Error_Msg(ret);
         }
 #ifdef DEBUG_SILK24
         __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG,
             "##### DECODED length: %d\n\t Frame #: %d", len);
 #endif
 //      frames++;
 //      outPtr  += len;
 //      tot_len += len;

 //  } while( DecControl.moreInternalDecoderFrames );

     env->SetShortArrayRegion(lin, 0, len,output_buffer);
     return (jint)len;
 }

 extern "C"
 JNIEXPORT void JNICALL Java_com_trunkbow_silk_SILK24_close
     (JNIEnv *env, jobject obj) {

     if (--codec_open != 0)
         return;
     /* Free decoder */
     free( psDec );
     /* Free Encoder */
     free( psEnc );
 }

    

        6、在Java层创建Speex工具类，内容如下：

           Silk8.java：

        

 class SILK8{
     /*
      *                 | fs (Hz) | BR (kbps)
      * ----------------+---------+---------
      * Narrowband      | 8000    | 6 -20
      * Mediumband      | 12000   | 7 -25
      * Wideband        | 16000   | 8 -30
      * Super Wideband  | 24000   | 12 -40
      *
      * Table 1: fs specifies the audio sampling frequency in Hertz (Hz); BR
      * specifies the adaptive bit rate range in kilobits per second (kbps).
      *
      * Complexity can be scaled to optimize for CPU resources in real-time,
      * mostly in trade-off to network bit rate. 0 is least CPU demanding and
      * highest bit rate.
      */
     private static final int DEFAULT_COMPLEXITY = 0;

     void load() {
          System.loadLibrary("silk8_jni");
     }

     public native int open(int compression);
     public native int decode(byte encoded[], short lin[], int size);
     public native int encode(short lin[], int offset, byte encoded[], int size);
     public native void close();
 }

         Silk16.java：

 class SILK16 {
     /*
      *                 | fs (Hz) | BR (kbps)
      * ----------------+---------+---------
      * Narrowband      | 8000