1 files changed, 180 insertions, 0 deletions
diff --git a/wavextract.c b/wavextract.c
new file mode 100644
index 0000000..4192f64
--- /dev/null
+++ b/wavextract.c
@@ -0,0 +1,180 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <math.h>
+#include <ctype.h>
+
+#define VERSION "0.1"
+
+#ifdef _WIN32
+	#define WIN32_LEAN_AND_MEAN
+	#include <windows.h>
+	#define PRIsize_t "Iu"
+	#define htole16(x) (x)
+	#define htole32(x) (x)
+#else
+	#define PRIsize_t "lu"
+#endif
+
+#pragma pack(push, 1)
+typedef struct /*_chunk_riff*/ {
+	char magic_riff[4];
+	uint32_t size;
+	char magic_wave[4];	
+} hdr_riff_t;
+
+typedef struct /*_chunk_fmt_base*/ {
+	char magic[4];
+	uint32_t size;
+	uint16_t fmt;
+	uint16_t channels;
+	uint32_t sample_rate;
+	uint32_t byte_rate; //(samplerate * sampleBits * channels) / 8.
+	uint16_t bitdepth; //(sampleBits * channels) / 8
+	uint16_t samplebits;
+	//uint16_t extsize; //only present if fmt != 1
+} hdr_fmt_t;
+
+typedef struct /*_chunk_fact*/ {
+	char magic[4];
+	uint32_t size;
+	uint32_t samples;
+} hdr_fact_t;
+
+typedef struct /*_chunk_data*/ {
+	char magic[4];
+	uint32_t size;
+} hdr_data_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");
+	return EXIT_FAILURE;
+}
+
+int main(int argc, char** argv){
+	size_t n;
+	#ifdef _WIN32
+	_fmode = _O_BINARY;
+	#endif
+
+	if(argc < 2){
+		return usage(argv[0]);
+	}
+
+	fprintf(stderr, "Opening wave input file %s\n", argv[1]);
+	int source_fd = open(argv[1], O_RDONLY);
+	if(source_fd < 0){
+		fprintf(stderr, "Failed to open input file %s: %s\n", argv[1], strerror(errno));
+		return EXIT_FAILURE;
+	}
+
+	hdr_riff_t riff;
+	if(read(source_fd, &riff, sizeof(riff)) != sizeof(riff)){
+		close(source_fd);
+		fprintf(stderr, "Failed to read input data: %s\n", strerror(errno));
+		return EXIT_FAILURE;	
+	}
+
+	if(memcmp(riff.magic_riff, "RIFF", 4) || memcmp(riff.magic_wave, "WAVE", 4)){
+		close(source_fd);
+		fprintf(stderr, "Invalid RIFF/WAVE magic\n");
+		return EXIT_FAILURE;
+	}
+
+	fprintf(stderr, "Chunk size: %d\n", riff.size);
+
+	hdr_fmt_t fmt;
+	uint16_t extra_data;
+	if(read(source_fd, &fmt, sizeof(fmt)) != sizeof(fmt)){
+		close(source_fd);
+		fprintf(stderr, "Failed to read input data: %s\n", strerror(errno));
+		return EXIT_FAILURE;	
+	}
+
+	if(memcmp(fmt.magic, "fmt ", 4)){
+		close(source_fd);
+		fprintf(stderr, "Invalid format magic\n");
+		return EXIT_FAILURE;
+	}
+
+	fprintf(stderr, "Format chunk size: %d\n", fmt.size);
+	fprintf(stderr, "Format: %d\n", fmt.fmt);
+	fprintf(stderr, "Channels: %d\n", fmt.channels);
+	fprintf(stderr, "Samplerate: %d\n", fmt.sample_rate);
+	fprintf(stderr, "Byterate: %d\n", fmt.byte_rate);
+	fprintf(stderr, "Align: %d\n", fmt.bitdepth);
+	fprintf(stderr, "Samplebits: %d\n", fmt.samplebits);
+
+	if(fmt.fmt != 1){
+		read(source_fd, &extra_data, 2);
+	}
+
+	if(fmt.fmt == 1 && fmt.size > 16){
+		fprintf(stderr, "Skipping %d additional header bytes\n", fmt.size - 16);
+		for(n = 16; n < fmt.size; n++){
+			read(source_fd, &extra_data, 1);
+		}
+	}
+
+	/* For now, just skip further analysis and bail on incompatible format */
+	if(fmt.samplebits != 16){
+		close(source_fd);
+		fprintf(stderr, "This format is currently not supported\n");
+		return EXIT_FAILURE;	
+	}
+
+	hdr_data_t data_header;
+	if(read(source_fd, &data_header, sizeof(data_header)) != sizeof(data_header)){
+		close(source_fd);
+		fprintf(stderr, "Failed to read input data: %s\n", strerror(errno));
+		return EXIT_FAILURE;	
+	}
+
+	if(memcmp(data_header.magic, "data", 4)){
+		close(source_fd);
+		fprintf(stderr, "Invalid data magic\n");
+		return EXIT_FAILURE;
+	}
+
+	fprintf(stderr, "%d bytes of sample data in file\n", data_header.size);
+
+	uint16_t sample;
+	uint8_t channel = 0;
+
+	for(n = 0; n < data_header.size / 2; n++){
+		//read sample
+		if(read(source_fd, &sample, 2) != 2){
+			close(source_fd);
+			fprintf(stderr, "Failed to read input data at sample %ld: %s\n", n, strerror(errno));
+			return EXIT_FAILURE;	
+		}
+
+		if(channel == 0){
+			printf("%ld,%d", n, (int16_t) sample);
+		}
+		else{
+			printf(",%d", (int16_t) sample);
+		}
+
+		if(channel == fmt.channels - 1){
+			printf("\n");
+		}
+
+		channel += 1;
+		channel %= fmt.channels;
+	}
+
+	close(source_fd);
+	fprintf(stderr, "All done\n");
+	return EXIT_SUCCESS;
+}