diff options
| author | japm48 <japm48@users.noreply.github.com> | 2020-04-14 18:28:18 +0200 |
|---|---|---|
| committer | Michael Dickens <michael.dickens@ettus.com> | 2020-04-14 15:47:29 -0400 |
| commit | 7975fb0f63bd90954960658be80790b7a518e64f (patch) | |
| tree | 53f376103c9dc93676368f5864c005e71c75097b /gr-blocks/lib/wavfile.cc | |
| parent | d0a351a6fc2f018f36f6e89395f346707a059099 (diff) | |
blocks: refactor and reorganize WAV internals
This includes the following:
- WAV header parameters are now stored in a struct.
- do not assume fixed position of data chunk (useful for appending).
- use INT{8,18}T_MAX/MIN.
- 0|NULL -> nullptr.
Diffstat (limited to 'gr-blocks/lib/wavfile.cc')
| -rw-r--r-- | gr-blocks/lib/wavfile.cc | 56 |
1 files changed, 32 insertions, 24 deletions
diff --git a/gr-blocks/lib/wavfile.cc b/gr-blocks/lib/wavfile.cc index 846de48177..2558d5c454 100644 --- a/gr-blocks/lib/wavfile.cc +++ b/gr-blocks/lib/wavfile.cc @@ -17,6 +17,7 @@ #include <stdint.h> #include <cstring> + namespace gr { namespace blocks { #define VALID_COMPRESSION_TYPE 0x0001 @@ -55,12 +56,7 @@ static inline uint32_t wav_to_host(uint32_t x) { return wtohl(x); } static inline uint16_t wav_to_host(uint16_t x) { return wtohs(x); } static inline int16_t wav_to_host(int16_t x) { return wtohs(x); } -bool wavheader_parse(FILE* fp, - unsigned int& sample_rate_o, - int& nchans_o, - int& bytes_per_sample_o, - int& first_sample_pos_o, - unsigned int& samples_per_chan_o) +bool wavheader_parse(FILE* fp, wav_header_info& info) { // _o variables take return values char str_buf[8] = { 0 }; @@ -167,11 +163,13 @@ bool wavheader_parse(FILE* fp, chunk_size = wav_to_host(chunk_size); // Output values - sample_rate_o = (unsigned)sample_rate; - nchans_o = (int)nchans; - bytes_per_sample_o = (int)(bits_per_sample / 8); - first_sample_pos_o = (int)ftell(fp); - samples_per_chan_o = (unsigned)(chunk_size / (bytes_per_sample_o * nchans)); + info.sample_rate = (unsigned)sample_rate; + info.nchans = (int)nchans; + info.bytes_per_sample = (int)(bits_per_sample / 8); + info.first_sample_pos = (int)ftell(fp); + info.samples_per_chan = (unsigned)(chunk_size / (info.bytes_per_sample * nchans)); + info.data_chunk_size = (unsigned)chunk_size; + return true; } @@ -241,30 +239,40 @@ void wav_write_sample(FILE* fp, short int sample, int bytes_per_sample) fwrite(data_ptr, 1, bytes_per_sample, fp); } - -bool wavheader_complete(FILE* fp, unsigned int byte_count) +inline bool fwrite_field_32(FILE* fp, long position, uint32_t data) { - uint32_t chunk_size = (uint32_t)byte_count; - chunk_size = host_to_wav(chunk_size); - - if (fseek(fp, 40, SEEK_SET) != 0) { + data = host_to_wav(data); + if (fseek(fp, position, SEEK_SET) != 0) { return false; } - fwrite(&chunk_size, 1, 4, fp); - chunk_size = (uint32_t)byte_count + 36; // fmt chunk and data header - chunk_size = host_to_wav(chunk_size); - if (fseek(fp, 4, SEEK_SET) != 0) { + return 4 == fwrite(&data, 1, 4, fp); +} + +bool wavheader_complete(FILE* fp, unsigned first_sample_pos) +{ + fseek(fp, 0L, SEEK_END); + long real_file_size = ftell(fp); + + if (first_sample_pos >= real_file_size) { return false; } - fwrite(&chunk_size, 1, 4, fp); + uint32_t field_data; + bool ok; - if (ferror(fp)) { + // Write "data chunk size". + field_data = uint32_t(real_file_size - first_sample_pos); + ok = fwrite_field_32(fp, first_sample_pos - 4, field_data); + if (!ok) { return false; } - return true; + // Write "total file size" - 8 + field_data = uint32_t(real_file_size - 8); + ok = fwrite_field_32(fp, 4, field_data); + + return ok; } } /* namespace blocks */ |