EngineX-Iluvatar/enginex_bi_series-sherpa-onnx
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Fix reading wave files with metadata (#21)

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This commit is contained in:
Fangjun Kuang
2022-10-18 14:56:34 +08:00
committed by GitHub
parent 8697a6d911
commit b78bdd9a2e
1 changed files with 22 additions and 6 deletions
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28
sherpa-onnx/csrc/wave-reader.cc
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@@ -25,7 +25,6 @@
#include <vector> #include <vector>
namespace sherpa_onnx { namespace sherpa_onnx {
namespace { namespace {
// see http://soundfile.sapp.org/doc/WaveFormat/ // see http://soundfile.sapp.org/doc/WaveFormat/
// //
@@ -33,10 +32,10 @@ namespace {
// TODO(fangjun): Support big endian // TODO(fangjun): Support big endian
struct WaveHeader { struct WaveHeader {
void Validate() const { void Validate() const {
// F F I R // F F I R
assert(chunk_id == 0x46464952); assert(chunk_id == 0x46464952);
assert(chunk_size == 36 + subchunk2_size); assert(chunk_size == 36 + subchunk2_size);
// E V A W // E V A W
assert(format == 0x45564157); assert(format == 0x45564157);
assert(subchunk1_id == 0x20746d66); assert(subchunk1_id == 0x20746d66);
assert(subchunk1_size == 16); // 16 for PCM assert(subchunk1_size == 16); // 16 for PCM
@@ -47,6 +46,22 @@ struct WaveHeader {
assert(bits_per_sample == 16); // we support only 16 bits per sample assert(bits_per_sample == 16); // we support only 16 bits per sample
} }
// See
// https://en.wikipedia.org/wiki/WAV#Metadata
// and
// https://www.robotplanet.dk/audio/wav_meta_data/riff_mci.pdf
void SeekToDataChunk(std::istream &is) {
// a t a d
while (subchunk2_id != 0x61746164) {
// const char *p = reinterpret_cast<const char *>(&subchunk2_id);
// printf("Skip chunk (%x): %c%c%c%c of size: %d\n", subchunk2_id, p[0],
// p[1], p[2], p[3], subchunk2_size);
is.seekg(subchunk2_size, std::istream::cur);
is.read(reinterpret_cast<char *>(&subchunk2_id), sizeof(int32_t));
is.read(reinterpret_cast<char *>(&subchunk2_size), sizeof(int32_t));
}
}
int32_t chunk_id; int32_t chunk_id;
int32_t chunk_size; int32_t chunk_size;
int32_t format; int32_t format;
@@ -58,8 +73,8 @@ struct WaveHeader {
int32_t byte_rate; int32_t byte_rate;
int16_t block_align; int16_t block_align;
int16_t bits_per_sample; int16_t bits_per_sample;
int32_t subchunk2_id; int32_t subchunk2_id; // a tag of this chunk
int32_t subchunk2_size; int32_t subchunk2_size; // size of subchunk2
}; };
static_assert(sizeof(WaveHeader) == 44, ""); static_assert(sizeof(WaveHeader) == 44, "");
@@ -69,9 +84,10 @@ std::vector<float> ReadWaveImpl(std::istream &is, float *sample_rate) {
WaveHeader header; WaveHeader header;
is.read(reinterpret_cast<char *>(&header), sizeof(header)); is.read(reinterpret_cast<char *>(&header), sizeof(header));
assert(static_cast<bool>(is)); assert(static_cast<bool>(is));
header.Validate(); header.Validate();
header.SeekToDataChunk(is);
*sample_rate = header.sample_rate; *sample_rate = header.sample_rate;
// header.subchunk2_size contains the number of bytes in the data. // header.subchunk2_size contains the number of bytes in the data.