Implement floating point sample format

1 files changed, 75 insertions, 20 deletions

diff --git a/wavextract.c b/wavextract.c
index 627406a..2198989 100644
--- a/wavextract.c
+++ b/wavextract.c
@@ -7,7 +7,7 @@
 #include <fcntl.h>
 #include <inttypes.h>
 
-#define VERSION "0.1"
+#define VERSION "0.2"
 
 #ifdef _WIN32
 	#define WIN32_LEAN_AND_MEAN
@@ -48,12 +48,20 @@ typedef struct /*_chunk_data*/ {
 	char magic[4];
 	uint32_t size;
 } hdr_data_t;
+
+typedef union {
+	int32_t i32;
+	int16_t i16;
+	float f32;
+	double f64;
+	uint8_t bytes[8];
+} sample_t;
 #pragma pack(pop)
 
 static int usage(char* fn){
 	fprintf(stdout, "wavextract " VERSION " - Convert WAVE files to CSV sample data\n");
 	fprintf(stdout, "\tUsage: %s <file.wav>\n\n", fn);
-	//fprintf(stdout, "Supported wave formats: i8, i16 (default), i32, f32, nf32\n");
+	fprintf(stdout, "Supported wave formats: PCM s16le, s32le, f32, f64\n");
 	return EXIT_FAILURE;
 }
 
@@ -116,7 +124,23 @@ int wave_verify_fmt(int fd, hdr_fmt_t* hdr){
 	return 0;
 }
 
-int wave_verify_data(int fd, hdr_data_t* hdr){
+int wave_verify_fact(int fd, hdr_fact_t* hdr){
+	if(read(fd, hdr, sizeof(hdr_fact_t)) != sizeof(hdr_fact_t)){
+		fprintf(stderr, "Failed to read input data: %s\n", strerror(errno));
+		return 1;
+	}
+
+	if(memcmp(hdr->magic, "fact", 4)){
+		fprintf(stderr, "Invalid data magic\n");
+		return 1;
+	}
+
+	fprintf(stderr, "Fact chunk size: %d\n", hdr->size);
+	fprintf(stderr, "%d samples per channel\n", hdr->samples);
+	return 0;
+}
+
+int wave_verify_data(int fd, hdr_data_t* hdr, size_t sample_bits, size_t channels){
 	if(read(fd, hdr, sizeof(hdr_data_t)) != sizeof(hdr_data_t)){
 		fprintf(stderr, "Failed to read input data: %s\n", strerror(errno));
 		return 1;
@@ -128,11 +152,39 @@ int wave_verify_data(int fd, hdr_data_t* hdr){
 	}
 
 	fprintf(stderr, "%d bytes of sample data in file\n", hdr->size);
+	if(hdr->size % (sample_bits / 8 * channels)){
+		fprintf(stderr, "Sample data unaligned, unable to decode\n");
+		return 1;
+	}
+	fprintf(stderr, "Data chunk maps to %" PRIsize_t " samples of data per channel\n", hdr->size / (sample_bits / 8 * channels));
 	return 0;
 }
 
+int print_sample(sample_t sample, uint16_t format, uint16_t samplebits){
+	if(format == 1){
+		if(samplebits == 16){
+			printf(",%d", sample.i16);
+			return 0;
+		}
+		else if(samplebits == 32){
+			printf(",%d", sample.i32);
+			return 0;
+		}
+	}
+	else if(format == 3){
+		if(samplebits == 32){
+			printf(",%.9g", sample.f32);
+			return 0;
+		}
+		else if(samplebits == 64){
+			printf(",%.17g", sample.f64);
+			return 0;
+		}
+	}
+	return 1;
+}
+
 int main(int argc, char** argv){
-	size_t n;
 	#ifdef _WIN32
 	_fmode = _O_BINARY;
 	#endif
@@ -150,48 +202,51 @@ int main(int argc, char** argv){
 
 	hdr_riff_t riff;
 	hdr_fmt_t fmt;
+	hdr_fact_t fact;
 	hdr_data_t data;
 
-	if(wave_verify_riff(source_fd, &riff)){
+	if(wave_verify_riff(source_fd, &riff) || wave_verify_fmt(source_fd, &fmt)){
 		close(source_fd);
 		return EXIT_FAILURE;
 	}
 
-	if(wave_verify_fmt(source_fd, &fmt)){
+	//non-pcm formats have an additional fact header
+	if(fmt.fmt != 1 && wave_verify_fact(source_fd, &fact)){
 		close(source_fd);
 		return EXIT_FAILURE;
 	}
 
-	if(wave_verify_data(source_fd, &data)){
+	if(wave_verify_data(source_fd, &data, fmt.samplebits, fmt.channels)){
 		close(source_fd);
 		return EXIT_FAILURE;
 	}
 
-	/* For now, just skip further analysis and bail on incompatible format */
-	if(fmt.samplebits != 16){
+	//compression currently unsupported
+	if((fmt.fmt != 1 && fmt.fmt != 3) || fmt.samplebits / 8 > sizeof(sample_t)){
 		close(source_fd);
 		fprintf(stderr, "This format is currently not supported\n");
-		return EXIT_FAILURE;	
+		return EXIT_FAILURE;
 	}
 
-	uint16_t sample;
-	uint8_t channel = 0;
+	sample_t sample;
+	size_t channel = 0;
+	size_t sample_offset = 0;
 
-	for(n = 0; n < data.size / 2; n++){
+	for(sample_offset = 0; sample_offset < data.size / (fmt.samplebits / 8 * fmt.channels); sample_offset++){
 		//read sample
-		if(read(source_fd, &sample, 2) != 2){
+		//TODO endianness conversion
+		if(read(source_fd, &sample, fmt.samplebits / 8) != fmt.samplebits / 8){
 			close(source_fd);
-			fprintf(stderr, "Failed to read input data at sample %" PRIsize_t ": %s\n", n, strerror(errno));
+			fprintf(stderr, "Failed to read input data at sample %" PRIsize_t ": %s\n", sample_offset, strerror(errno));
 			return EXIT_FAILURE;	
 		}
 
 		if(channel == 0){
-			printf("%" PRIsize_t ",%d", n, (int16_t) sample);
-		}
-		else{
-			printf(",%d", (int16_t) sample);
+			printf("%" PRIsize_t "", sample_offset);
 		}
 
+		print_sample(sample, fmt.fmt, fmt.samplebits);
+
 		if(channel == fmt.channels - 1){
 			printf("\n");
 		}
@@ -201,6 +256,6 @@ int main(int argc, char** argv){
 	}
 
 	close(source_fd);
-	fprintf(stderr, "Done, exported %" PRIsize_t " frames of data %d channels, processed %" PRIsize_t " samples\n", n, fmt.channels, fmt.channels * n);
+	fprintf(stderr, "Done, exported %" PRIsize_t " frames of data %d channels, processed %" PRIsize_t " samples\n", sample_offset, fmt.channels, fmt.channels * sample_offset);
 	return EXIT_SUCCESS;
 }