#include "wav_utils.h" #include "../src/util/reader_put.h" static int make_riff_chunk(uint8_t* buf, wav_header_t* wav, uint32_t header_size, uint32_t data_size) { put_data (buf+0x00, "RIFF", 0x04); put_u32le(buf+0x04, header_size - 0x08 + data_size); put_data (buf+0x08, "WAVE", 0x04); return 0x08 + 0x04; } static int make_fmt_chunk(uint8_t* buf, wav_header_t* wav) { int codec = wav->is_float ? 0x0003 : 0x0001; /* PCM */ int bytes_per_second = wav->sample_rate * wav->channels * wav->sample_size; int16_t block_align = wav->channels * wav->sample_size; int bits_per_sample = wav->sample_size * 8; put_data (buf + 0x00, "fmt ", 0x04); put_u32le(buf + 0x04, 0x10); put_s16le(buf + 0x08, codec); put_s16le(buf + 0x0a, wav->channels); put_s32le(buf + 0x0c, wav->sample_rate); put_s32le(buf + 0x10, bytes_per_second); put_s16le(buf + 0x14, block_align); put_s16le(buf + 0x16, bits_per_sample); return 0x08 + 0x10; } /* see riff.c */ static int make_smpl_chunk(uint8_t* buf, wav_header_t* wav) { put_data (buf + 0x00, "smpl", 0x04); put_s32le(buf + 0x04, 0x3c); for (int i = 0; i < 7; i++) { put_s32le(buf + 0x08 + i * 0x04, 0); } put_s32le(buf + 0x24, 1); for (int i = 0; i < 3; i++) { put_s32le(buf + 0x28 + i * 0x04, 0); } put_s32le(buf + 0x34, wav->loop_start); put_s32le(buf + 0x38, wav->loop_end); put_s32le(buf + 0x3C, 0); put_s32le(buf + 0x40, 0); return 0x08 + 0x3c; } static int make_data_chunk(uint8_t* buf, wav_header_t* wav, uint32_t data_size) { put_data (buf + 0x00, "data", 0x04); put_u32le(buf + 0x04, data_size); return 0x08; } /* make a RIFF header for .wav */ size_t wav_make_header(uint8_t* buf, size_t buf_size, wav_header_t* wav) { size_t header_size; /* RIFF + fmt + smpl + data */ header_size = 0x08 + 0x04; header_size += 0x08 + 0x10; if (wav->write_smpl_chunk && wav->loop_end) header_size += 0x08 + 0x3c; header_size += 0x08; if (header_size > buf_size) return 0; if (!wav->sample_size) wav->sample_size = sizeof(short); if (wav->sample_size <= 0x00 || wav->sample_size > 0x04) return 0; size_t data_size = wav->sample_count * wav->channels * wav->sample_size; int size; size = make_riff_chunk(buf, wav, header_size, data_size); buf += size; size = make_fmt_chunk(buf, wav); buf += size; if (wav->write_smpl_chunk && wav->loop_end) { size = make_smpl_chunk(buf, wav); buf += size; } size = make_data_chunk(buf, wav, data_size); buf += size; /* could try to add channel_layout but would need WAVEFORMATEXTENSIBLE */ return header_size; } static inline void swap_value(uint8_t* buf, int sample_size) { for (int i = 0; i < sample_size / 2; i++) { char temp = buf[i]; buf[i] = buf[sample_size - i - 1]; buf[sample_size - i - 1] = temp; } } /* when endianness is LE buffer is correct already and this function can be skipped */ void wav_swap_samples_le(void* samples, int samples_len, int sample_size) { /* Windows can't be BE... I think */ #if !defined(_WIN32) #if !defined(__BYTE_ORDER__) || __BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__ if (!sample_size) sample_size = sizeof(short); /* 16b sample in memory is AABB where AA=MSB, BB=LSB, swap to BBAA */ uint8_t* buf = samples; for (int i = 0; i < samples_len; i += sample_size) { swap_value(buf + i, sample_size); } #endif #endif }