SWORD1: Improve detection of speech data endianness for mac version

Before trying an heuristic on the decoded data it simply checks if we get the expected resource size after decompression. When using the wrong endianness this is unlikely to be the case.
scummvm · Jun 6, 2016 · 5031885 · 5031885
1 parent a7eb756
commit 5031885
Show file tree

Hide file tree

Showing 2 changed files with 26 additions and 7 deletions.
diff --git a/engines/sword1/sound.cpp b/engines/sword1/sound.cpp
@@ -124,22 +124,29 @@ void Sound::checkSpeechFileEndianness() {
 	uint32 index = _cowHeader[locIndex + (localNo * 2) - 1];
 	if (sampleSize) {
 		uint32 size;
+		bool leOk = false, beOk = false;
 		// Compute average of difference between two consecutive samples for both BE and LE
 		_bigEndianSpeech = false;
-		int16 *data = uncompressSpeech(index + _cowHeaderSize, sampleSize, &size);
+		int16 *data = uncompressSpeech(index + _cowHeaderSize, sampleSize, &size, &leOk);
 		uint32 maxSamples = size > 2000 ? 2000 : size;
 		double le_diff = endiannessHeuristicValue(data, size, maxSamples);
 		delete[] data;
 		_bigEndianSpeech = true;
-		data = uncompressSpeech(index + _cowHeaderSize, sampleSize, &size);
+		data = uncompressSpeech(index + _cowHeaderSize, sampleSize, &size, &beOk);
 		double be_diff = endiannessHeuristicValue(data, size, maxSamples);
 		delete [] data;
 		// Set the big endian flag
-		_bigEndianSpeech = (be_diff < le_diff);
+		if (leOk && !beOk)
+			_bigEndianSpeech = false;
+		else if (beOk && !leOk)
+			_bigEndianSpeech = true;
+		else
+			_bigEndianSpeech = (be_diff < le_diff);
 		if (_bigEndianSpeech)
 			debug(6, "Mac version: using big endian speech file");
 		else
 			debug(6, "Mac version: using little endian speech file");
+		debug(8, "Speech decompression memory check: big endian = %s, little endian = %s", beOk ? "good" : "bad", leOk ? "good" : "bad");
 		debug(8, "Speech endianness heuristic: average = %f for BE and %f for LE (%d samples)", be_diff, le_diff, maxSamples);
 	}
 }
@@ -445,7 +452,7 @@ bool Sound::startSpeech(uint16 roomNo, uint16 localNo) {
 		return false;
 }
 
-int16 *Sound::uncompressSpeech(uint32 index, uint32 cSize, uint32 *size) {
+int16 *Sound::uncompressSpeech(uint32 index, uint32 cSize, uint32 *size, bool* ok) {
 	uint8 *fBuf = (uint8 *)malloc(cSize);
 	_cowFile.seek(index);
 	_cowFile.read(fBuf, cSize);
@@ -455,6 +462,8 @@ int16 *Sound::uncompressSpeech(uint32 index, uint32 cSize, uint32 *size) {
 		headerPos++;
 
 	if (headerPos < 100) {
+		if (ok != 0)
+			*ok = true;
 		int32 resSize;
 		int16 *srcData;
 		uint32 srcPos;
@@ -507,8 +516,11 @@ int16 *Sound::uncompressSpeech(uint32 index, uint32 cSize, uint32 *size) {
 			srcPos++;
 			if (length < 0) {
 				length = -length;
-				if (length > samplesLeft)
+				if (length > samplesLeft) {
 					length = samplesLeft;
+					if (ok != 0)
+						*ok = false;
+				}
 				int16 value;
 				if (_bigEndianSpeech) {
 					value = (int16)SWAP_BYTES_16(*((uint16 *)(srcData + srcPos)));
@@ -519,8 +531,11 @@ int16 *Sound::uncompressSpeech(uint32 index, uint32 cSize, uint32 *size) {
 					dstData[dstPos++] = value;
 				srcPos++;
 			} else {
-				if (length > samplesLeft)
+				if (length > samplesLeft) {
 					length = samplesLeft;
+					if (ok != 0)
+						*ok = false;
+				}
 				if (_bigEndianSpeech) {
 					for (uint16 cnt = 0; cnt < (uint16)length; cnt++)
 						dstData[dstPos++] = (int16)SWAP_BYTES_16(*((uint16 *)(srcData + (srcPos++))));
@@ -534,6 +549,8 @@ int16 *Sound::uncompressSpeech(uint32 index, uint32 cSize, uint32 *size) {
 		}
 		if (samplesLeft > 0) {
 			memset(dstData + dstPos, 0, samplesLeft * 2);
+			if (ok != 0)
+				*ok = false;
 		}
 		if (_cowMode == CowDemo) // demo has wave output size embedded in the compressed data
 			*(uint32 *)dstData = 0;
@@ -542,6 +559,8 @@ int16 *Sound::uncompressSpeech(uint32 index, uint32 cSize, uint32 *size) {
 		calcWaveVolume(dstData, resSize);
 		return dstData;
 	} else {
+		if (ok != 0)
+			*ok = false;
 		free(fBuf);
 		warning("Sound::uncompressSpeech(): DATA tag not found in wave header");
 		*size = 0;

diff --git a/engines/sword1/sound.h b/engines/sword1/sound.h
@@ -110,7 +110,7 @@ class Sound {
 	void initCowSystem();
 
 	uint32 getSampleId(int32 fxNo);
-	int16 *uncompressSpeech(uint32 index, uint32 cSize, uint32 *size);
+	int16 *uncompressSpeech(uint32 index, uint32 cSize, uint32 *size, bool* ok = 0);
 	void calcWaveVolume(int16 *data, uint32 length);
 	bool _waveVolume[WAVE_VOL_TAB_LENGTH];
 	uint16 _waveVolPos;