Merge pull request #47 from occ-ai/roy.fix_win32_unicode_model_path

Fix windows Unicode model path and characters display

src/transcription-filter.cpp

@@ -193,6 +193,40 @@ void acquire_weak_text_source_ref(struct transcription_filter_data *gf)
 	}
 }
 
+#define is_lead_byte(c) (((c)&0xe0) == 0xc0 || ((c)&0xf0) == 0xe0 || ((c)&0xf8) == 0xf0)
+#define is_trail_byte(c) (((c)&0xc0) == 0x80)
+
+inline int lead_byte_length(const uint8_t c)
+{
+	if ((c & 0xe0) == 0xc0) {
+		return 2;
+	} else if ((c & 0xf0) == 0xe0) {
+		return 3;
+	} else if ((c & 0xf8) == 0xf0) {
+		return 4;
+	} else {
+		return 1;
+	}
+}
+
+inline bool is_valid_lead_byte(const uint8_t *c)
+{
+	const int length = lead_byte_length(c[0]);
+	if (length == 1) {
+		return true;
+	}
+	if (length == 2 && is_trail_byte(c[1])) {
+		return true;
+	}
+	if (length == 3 && is_trail_byte(c[1]) && is_trail_byte(c[2])) {
+		return true;
+	}
+	if (length == 4 && is_trail_byte(c[1]) && is_trail_byte(c[2]) && is_trail_byte(c[3])) {
+		return true;
+	}
+	return false;
+}
+
 void set_text_callback(struct transcription_filter_data *gf,
 		       const DetectionResultWithText &resultIn)
 {
@@ -212,18 +246,39 @@ void set_text_callback(struct transcription_filter_data *gf,
 
 #ifdef _WIN32
 	// Some UTF8 charsets on Windows output have a bug, instead of 0xd? it outputs
-	// 0xf?, and 0xc? becomes 0xe?, so we need to replace it.
-	std::string str_copy = result.text;
-	for (size_t i = 0; i < str_copy.size(); ++i) {
-		// if the char MSBs starts with 0xf replace the MSBs with 0xd
-		if ((str_copy.c_str()[i] & 0xf0) == 0xf0) {
-			str_copy[i] = (str_copy.c_str()[i] & 0x0f) | 0xd0;
-		}
-		// if the char MSBs starts with 0xe replace the char with 0xc
-		if ((str_copy.c_str()[i] & 0xf0) == 0xe0) {
-			str_copy[i] = (str_copy.c_str()[i] & 0x0f) | 0xc0;
+	// 0xf?, and 0xc? becomes 0xe?, so we need to fix it.
+	std::stringstream ss;
+	uint8_t *c_str = (uint8_t *)result.text.c_str();
+	for (size_t i = 0; i < result.text.size(); ++i) {
+		if (is_lead_byte(c_str[i])) {
+			// this is a unicode leading byte
+			// if the next char is 0xff - it's a bug char, replace it with 0x9f
+			if (c_str[i + 1] == 0xff) {
+				c_str[i + 1] = 0x9f;
+			}
+			if (!is_valid_lead_byte(c_str + i)) {
+				// This is a bug lead byte, because it's length 3 and the i+2 byte is also
+				// a lead byte
+				c_str[i] = c_str[i] - 0x20;
+			}
+		} else {
+			if (c_str[i] >= 0xf8) {
+				// this may be a malformed lead byte.
+				// lets see if it becomes a valid lead byte if we "fix" it
+				uint8_t buf_[4];
+				buf_[0] = c_str[i] - 0x20;
+				buf_[1] = c_str[i + 1];
+				buf_[2] = c_str[i + 2];
+				buf_[3] = c_str[i + 3];
+				if (is_valid_lead_byte(buf_)) {
+					// this is a malformed lead byte, fix it
+					c_str[i] = c_str[i] - 0x20;
+				}
+			}
 		}
 	}
+
+	std::string str_copy = (char *)c_str;
 #else
 	std::string str_copy = result.text;
 #endif

src/whisper-processing.cpp

@@ -9,6 +9,11 @@
 #include <algorithm>
 #include <cctype>
 
+#ifdef _WIN32
+#include <fstream>
+#include <Windows.h>
+#endif
+
 #define VAD_THOLD 0.0001f
 #define FREQ_THOLD 100.0f
 
@@ -73,7 +78,34 @@ bool vad_simple(float *pcmf32, size_t pcm32f_size, uint32_t sample_rate, float v
 struct whisper_context *init_whisper_context(const std::string &model_path)
 {
 	obs_log(LOG_INFO, "Loading whisper model from %s", model_path.c_str());
+
+#ifdef _WIN32
+	// convert model path UTF8 to wstring (wchar_t) for whisper
+	int count = MultiByteToWideChar(CP_UTF8, 0, model_path.c_str(), (int)model_path.length(),
+					NULL, 0);
+	std::wstring model_path_ws(count, 0);
+	MultiByteToWideChar(CP_UTF8, 0, model_path.c_str(), (int)model_path.length(),
+			    &model_path_ws[0], count);
+
+	// Read model into buffer
+	std::ifstream modelFile(model_path_ws, std::ios::binary);
+	if (!modelFile.is_open()) {
+		obs_log(LOG_ERROR, "Failed to open whisper model file %s", model_path.c_str());
+		return nullptr;
+	}
+	modelFile.seekg(0, std::ios::end);
+	const size_t modelFileSize = modelFile.tellg();
+	modelFile.seekg(0, std::ios::beg);
+	std::vector<char> modelBuffer(modelFileSize);
+	modelFile.read(modelBuffer.data(), modelFileSize);
+	modelFile.close();
+
+	// Initialize whisper
+	struct whisper_context *ctx = whisper_init_from_buffer(modelBuffer.data(), modelFileSize);
+#else
 	struct whisper_context *ctx = whisper_init_from_file(model_path.c_str());
+#endif
+
 	if (ctx == nullptr) {
 		obs_log(LOG_ERROR, "Failed to load whisper model");
 		return nullptr;