Performing per-utterance cepstral mean normalization
See discussion in https://sourceforge.net/p/cmusphinx/discussion/help/thread/51e2979b/
This commit is contained in:
parent
f4f9ffe883
commit
d97c880754
|
@ -2,6 +2,7 @@
|
|||
|
||||
using std::function;
|
||||
using std::vector;
|
||||
using std::unique_ptr;
|
||||
|
||||
// Converts a float in the range -1..1 to a signed 16-bit int
|
||||
inline int16_t floatSampleToInt16(float sample) {
|
||||
|
@ -38,3 +39,11 @@ void process16bitAudioClip(const AudioClip& audioClip, function<void(const vecto
|
|||
process16bitAudioClip(audioClip, processBuffer, capacity, progressSink);
|
||||
}
|
||||
|
||||
unique_ptr<vector<int16_t>> copyTo16bitBuffer(const AudioClip& audioClip) {
|
||||
auto result = std::make_unique<vector<int16_t>>(static_cast<size_t>(audioClip.size()));
|
||||
int index = 0;
|
||||
for (float sample : audioClip) {
|
||||
(*result)[index++] = floatSampleToInt16(sample);
|
||||
}
|
||||
return std::move(result);
|
||||
}
|
||||
|
|
|
@ -7,3 +7,4 @@
|
|||
|
||||
void process16bitAudioClip(const AudioClip& audioClip, std::function<void(const std::vector<int16_t>&)> processBuffer, size_t bufferCapacity, ProgressSink& progressSink);
|
||||
void process16bitAudioClip(const AudioClip& audioClip, std::function<void(const std::vector<int16_t>&)> processBuffer, ProgressSink& progressSink);
|
||||
std::unique_ptr<std::vector<int16_t>> copyTo16bitBuffer(const AudioClip& audioClip);
|
|
@ -96,7 +96,7 @@ void sphinxLogCallback(void* user_data, err_lvl_t errorLevel, const char* format
|
|||
logging::log(logLevel, message);
|
||||
}
|
||||
|
||||
BoundedTimeline<string> recognizeWords(const AudioClip& inputAudioClip, ps_decoder_t& decoder, bool& decoderIsStillUsable, ProgressSink& progressSink) {
|
||||
BoundedTimeline<string> recognizeWords(const AudioClip& inputAudioClip, ps_decoder_t& decoder, bool& decoderIsStillUsable) {
|
||||
// Convert audio stream to the exact format PocketSphinx requires
|
||||
const unique_ptr<AudioClip> audioClip = inputAudioClip.clone() | resample(sphinxSampleRate);
|
||||
|
||||
|
@ -107,12 +107,12 @@ BoundedTimeline<string> recognizeWords(const AudioClip& inputAudioClip, ps_decod
|
|||
int error = ps_start_utt(&decoder);
|
||||
if (error) throw runtime_error("Error starting utterance processing for word recognition.");
|
||||
|
||||
// Process entire sound stream
|
||||
auto processBuffer = [&decoder](const vector<int16_t>& buffer) {
|
||||
int searchedFrameCount = ps_process_raw(&decoder, buffer.data(), buffer.size(), false, false);
|
||||
// Process entire audio clip
|
||||
auto buffer = copyTo16bitBuffer(*audioClip);
|
||||
const bool noRecognition = false;
|
||||
const bool fullUtterance = true;
|
||||
int searchedFrameCount = ps_process_raw(&decoder, buffer->data(), buffer->size(), noRecognition, fullUtterance);
|
||||
if (searchedFrameCount < 0) throw runtime_error("Error analyzing raw audio data for word recognition.");
|
||||
};
|
||||
process16bitAudioClip(*audioClip, processBuffer, progressSink);
|
||||
|
||||
// End recognition
|
||||
error = ps_end_utt(&decoder);
|
||||
|
@ -154,8 +154,7 @@ s3wid_t getWordId(const string& word, dict_t& dictionary) {
|
|||
optional<Timeline<Phone>> getPhoneAlignment(
|
||||
const vector<s3wid_t>& wordIds,
|
||||
const AudioClip& inputAudioClip,
|
||||
ps_decoder_t& decoder,
|
||||
ProgressSink& progressSink)
|
||||
ps_decoder_t& decoder)
|
||||
{
|
||||
// Create alignment list
|
||||
lambda_unique_ptr<ps_alignment_t> alignment(
|
||||
|
@ -190,18 +189,17 @@ optional<Timeline<Phone>> getPhoneAlignment(
|
|||
// Start search
|
||||
ps_search_start(search.get());
|
||||
|
||||
// Process entire sound stream
|
||||
auto processBuffer = [&](const vector<int16_t>& buffer) {
|
||||
const int16* nextSample = buffer.data();
|
||||
size_t remainingSamples = buffer.size();
|
||||
while (acmod_process_raw(acousticModel, &nextSample, &remainingSamples, false) > 0) {
|
||||
// Process entire audio clip
|
||||
auto buffer = copyTo16bitBuffer(*audioClip);
|
||||
const int16* nextSample = buffer->data();
|
||||
size_t remainingSamples = buffer->size();
|
||||
bool fullUtterance = true;
|
||||
while (acmod_process_raw(acousticModel, &nextSample, &remainingSamples, fullUtterance) > 0) {
|
||||
while (acousticModel->n_feat_frame > 0) {
|
||||
ps_search_step(search.get(), acousticModel->output_frame);
|
||||
acmod_advance(acousticModel);
|
||||
}
|
||||
}
|
||||
};
|
||||
process16bitAudioClip(*audioClip, processBuffer, progressSink);
|
||||
|
||||
// End search
|
||||
error = ps_search_finish(search.get());
|
||||
|
@ -263,6 +261,8 @@ lambda_unique_ptr<ps_decoder_t> createDecoder(optional<u32string> dialog) {
|
|||
"-dither", "yes",
|
||||
// Disable VAD -- we're doing that ourselves
|
||||
"-remove_silence", "no",
|
||||
// Perform per-utterance cepstral mean normalization
|
||||
"-cmn", "batch",
|
||||
nullptr),
|
||||
[](cmd_ln_t* config) { cmd_ln_free_r(config); });
|
||||
if (!config) throw runtime_error("Error creating configuration.");
|
||||
|
@ -309,7 +309,8 @@ Timeline<Phone> utteranceToPhones(
|
|||
const unique_ptr<AudioClip> clipSegment = audioClip.clone() | segment(utterance);
|
||||
|
||||
// Get words
|
||||
BoundedTimeline<string> words = recognizeWords(*clipSegment, decoder, decoderIsStillUsable, wordRecognitionProgressSink);
|
||||
BoundedTimeline<string> words = recognizeWords(*clipSegment, decoder, decoderIsStillUsable);
|
||||
wordRecognitionProgressSink.reportProgress(1.0);
|
||||
for (Timed<string> timedWord : words) {
|
||||
timedWord.getTimeRange().shift(utterance.getStart());
|
||||
logging::logTimedEvent("word", timedWord);
|
||||
|
@ -326,8 +327,9 @@ Timeline<Phone> utteranceToPhones(
|
|||
#if BOOST_VERSION < 105600 // Support legacy syntax
|
||||
#define value_or get_value_or
|
||||
#endif
|
||||
Timeline<Phone> segmentPhones = getPhoneAlignment(wordIds, *clipSegment, decoder, alignmentProgressSink)
|
||||
Timeline<Phone> segmentPhones = getPhoneAlignment(wordIds, *clipSegment, decoder)
|
||||
.value_or(ContinuousTimeline<Phone>(clipSegment->getTruncatedRange(), Phone::Noise));
|
||||
alignmentProgressSink.reportProgress(1.0);
|
||||
segmentPhones.shift(utterance.getStart());
|
||||
for (const auto& timedPhone : segmentPhones) {
|
||||
logging::logTimedEvent("rawPhone", timedPhone);
|
||||
|
|
Loading…
Reference in New Issue