我通过在 Visual Studio 2010 中将我自己的 C++ 项目编译为 DLL 将 CMU 的 PocketSphinx 与 Unity 集成，我从 Unity Pro 中的 C# 脚本调用它。我知道 dll 可以工作，因为我已经使用相同的代码将另一个项目作为 exe 进行了编译，并且它可以作为独立程序完美运行。我正在使用 pocketsphinx_continuous 项目示例，它获取麦克风输入并将文本输出到控制台。我已自定义此代码以从 Unity 内部调用，它应该作为字符串而不是控制台输出回我的 C# 代码。我觉得我几乎可以正常工作，但是 const char * 只是没有将其作为字符串返回。如果我使用这个声明，我最终会遇到访问冲突错误：
私有静态外部字符串识别来自麦克风（）；
所以，我尝试使用这个：
私有静态外部 IntPtr identify_from_microphone();
然后，我使用这行代码尝试打印该函数的输出：
print("你刚才说" + Marshal.PtrToStringAnsi(recognize_from_microphone()));
但是，然后我得到的只是“你刚才说的”作为回报。如果我这样做，我可以设法取回内存地址： print("you just said " + identify_from_microphone()); 所以，我知道有些东西正在被退回。
这是我的 C++ 代码（其中大部分最初是用 C 编写的，作为来自 pocketsphinx 的示例代码）：
char* MakeStringCopy (const char* str)
{
if (str == NULL) return NULL;
char* res = (char*)malloc(strlen(str) + 1);
strcpy(res, str);
return res;
}
extern __declspec(dllexport) const char * recognize_from_microphone()
{
//this is a near complete duplication of the code from main()
char const *cfg;
config = cmd_ln_init(NULL, ps_args(), TRUE,
"-hmm", MODELDIR "\\hmm\\en_US\\hub4wsj_sc_8k",
"-lm", MODELDIR "\\lm\\en\\turtle.DMP",
"-dict", MODELDIR "\\lm\\en\\turtle.dic",
NULL);
if (config == NULL)
{
return "config is null";
}
ps = ps_init(config);
if (ps == NULL)
{
return "ps is null";
}
ad_rec_t *ad;
int16 adbuf[4096];
int32 k, ts, rem;
char const *hyp;
char const *uttid;
cont_ad_t *cont;
char word[256];
char words[1024] = "";
//char temp[] = "hypothesis";
//hyp = temp;
if ((ad = ad_open_dev(cmd_ln_str_r(config, "-adcdev"),
(int)cmd_ln_float32_r(config, "-samprate"))) == NULL)
E_FATAL("Failed to open audio device\n");
/* Initialize continuous listening module */
if ((cont = cont_ad_init(ad, ad_read)) == NULL)
E_FATAL("Failed to initialize voice activity detection\n");
if (ad_start_rec(ad) < 0)
E_FATAL("Failed to start recording\n");
if (cont_ad_calib(cont) < 0)
E_FATAL("Failed to calibrate voice activity detection\n");
for (;;) {
/* Indicate listening for next utterance */
//printf("READY....\n");
fflush(stdout);
fflush(stderr);
/* Wait data for next utterance */
while ((k = cont_ad_read(cont, adbuf, 4096)) == 0)
sleep_msec(100);
if (k < 0)
E_FATAL("Failed to read audio\n");
/*
* Non-zero amount of data received; start recognition of new utterance.
* NULL argument to uttproc_begin_utt => automatic generation of utterance-id.
*/
if (ps_start_utt(ps, NULL) < 0)
E_FATAL("Failed to start utterance\n");
ps_process_raw(ps, adbuf, k, FALSE, FALSE);
//printf("Listening...\n");
fflush(stdout);
/* Note timestamp for this first block of data */
ts = cont->read_ts;
/* Decode utterance until end (marked by a "long" silence, >1sec) */
for (;;) {
/* Read non-silence audio data, if any, from continuous listening module */
if ((k = cont_ad_read(cont, adbuf, 4096)) < 0)
E_FATAL("Failed to read audio\n");
if (k == 0) {
/*
* No speech data available; check current timestamp with most recent
* speech to see if more than 1 sec elapsed. If so, end of utterance.
*/
if ((cont->read_ts - ts) > DEFAULT_SAMPLES_PER_SEC)
break;
}
else {
/* New speech data received; note current timestamp */
ts = cont->read_ts;
}
/*
* Decode whatever data was read above.
*/
rem = ps_process_raw(ps, adbuf, k, FALSE, FALSE);
/* If no work to be done, sleep a bit */
if ((rem == 0) && (k == 0))
sleep_msec(20);
}
/*
* Utterance ended; flush any accumulated, unprocessed A/D data and stop
* listening until current utterance completely decoded
*/
ad_stop_rec(ad);
while (ad_read(ad, adbuf, 4096) >= 0);
cont_ad_reset(cont);
fflush(stdout);
/* Finish decoding, obtain and print result */
ps_end_utt(ps);
hyp = ps_get_hyp(ps, NULL, &uttid);
fflush(stdout);
/* Exit if the first word spoken was GOODBYE */
//actually, for unity, exit if any word was spoken at all! this will avoid an infinite loop of doom!
if (hyp) {
/*sscanf(hyp, "%s", words);
if (strcmp(word, "goodbye") == 0)*/
break;
}
else
return "nothing returned";
/* Resume A/D recording for next utterance */
if (ad_start_rec(ad) < 0)
E_FATAL("Failed to start recording\n");
}
cont_ad_close(cont);
ad_close(ad);
ps_free(ps);
const char *temp = new char[1024];
temp = MakeStringCopy(hyp);
return temp;}
如果更改返回温度；返回“这里的一些字符串”；然后我看到文本出现在 Unity 中。不过，这并没有什么帮助，因为我不需要硬编码文本，我需要语音识别代码的输出，它最终存储在 hyp 变量中。
谁能帮我弄清楚我做错了什么？谢谢！