ffmpeg pcm_mulaw jni

jint Java_com_encoder_util_EncADPCM_InitEncoder(JNIEnv* env, jobject thiz, jint samplerate, jint bitrate, jint channels, jint codeccode) {
    avcodec_register_all();
    av_init_packet(&packet);
    av_log_set_level(AV_LOG_VERBOSE);
    av_log_set_callback(log_callback);
    switch(codeccode) {
        case 0: codec = avcodec_find_encoder(AV_CODEC_ID_ADPCM_IMA_QT); break;
        case 1: codec = avcodec_find_encoder(AV_CODEC_ID_ADPCM_IMA_WAV); break;
        case 2: codec = avcodec_find_encoder(AV_CODEC_ID_ADPCM_G726); break;
        case 3: codec = avcodec_find_encoder(AV_CODEC_ID_ADPCM_G722); break;
        case 4: codec = avcodec_find_encoder(AV_CODEC_ID_PCM_ALAW); break;
        case 5: codec = avcodec_find_encoder(AV_CODEC_ID_PCM_MULAW); break;
        default: codec = NULL;
    }
    if (codec == NULL) {
        __android_log_print(ANDROID_LOG_VERBOSE, "INITENC", "something is wrong with codec", 1);
        return -1;
    } else {
        __android_log_print(ANDROID_LOG_VERBOSE, "INITENC", "codec inited: %s", codec->name);
    }
    c = avcodec_alloc_context3(codec);
    if (c==NULL) {
        __android_log_print(ANDROID_LOG_VERBOSE, "INITENC", "something is wrong with context", 1);
        return -2;
    } else {
        c->sample_rate=samplerate;
        //c->bit_rate=bitrate;
        c->sample_fmt = AV_SAMPLE_FMT_S16;
        c->channel_layout = av_get_default_channel_layout(1);
        c->channels = av_get_channel_layout_nb_channels(c->channel_layout);
    }
    avcodec_open2(c, codec, NULL);
    frame = av_frame_alloc();
    if (frame == NULL) {
        __android_log_print(ANDROID_LOG_VERBOSE, "INITENC", "something is wrong with frame alloc");
        return -4;
    }
    frame->nb_samples = 640;
    frame->format = c->sample_fmt;
    frame->channel_layout = c->channel_layout;
    int error = av_frame_get_buffer(frame, 0);
    __android_log_print(ANDROID_LOG_VERBOSE, "INITENC", "framegetbuffer %d", error);
    firstTime = true;
    return 0;
}

jint Java_com_encoder_util_EncADPCM_EncodeFrame(JNIEnv* env, jobject thiz, jbyteArray in, jint frameLen, jbyteArray out) {
    jbyte* buf = env->GetByteArrayElements(in, 0);
    jbyte* result = env->GetByteArrayElements(out, 0);
    __android_log_print(ANDROID_LOG_VERBOSE, "encoder", "framelen = %d", frameLen);
    int gotOutput;
    __android_log_print(ANDROID_LOG_VERBOSE, "encoder", "channels = %d, sample fmt = %d, buffer[0] = %d, buffersize = %d", c->channels, c->sample_fmt, (uint8_t)(*buf), frameLen);
    int ret = avcodec_fill_audio_frame(frame, c->channels, c->sample_fmt, (uint8_t*)buf, frameLen, 0);
    if (ret<0) {
        __android_log_print(ANDROID_LOG_VERBOSE, "audenc", "something is wrong with filling audio frame %d", ret);
        return ret;
    }
    ret = avcodec_encode_audio2(c, &packet, frame, &gotOutput);
    __android_log_print(ANDROID_LOG_VERBOSE, "audenc", "gotOutput = %d", gotOutput);
    if (ret >= 0 && gotOutput > 0) {
        for (int i=0; i<frameLen/2; i++) {
            result[i] = packet.data[i];
        }
    }
    (env)->ReleaseByteArrayElements(in, buf, 0);
    (env)->ReleaseByteArrayElements(out, result, 0);
    return frameLen/2;
}