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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
commit | 36d22d82aa202bb199967e9512281e9a53db42c9 (patch) | |
tree | 105e8c98ddea1c1e4784a60a5a6410fa416be2de /third_party/libwebrtc/common_audio/wav_header.cc | |
parent | Initial commit. (diff) | |
download | firefox-esr-upstream.tar.xz firefox-esr-upstream.zip |
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/libwebrtc/common_audio/wav_header.cc')
-rw-r--r-- | third_party/libwebrtc/common_audio/wav_header.cc | 435 |
1 files changed, 435 insertions, 0 deletions
diff --git a/third_party/libwebrtc/common_audio/wav_header.cc b/third_party/libwebrtc/common_audio/wav_header.cc new file mode 100644 index 0000000000..bca209a665 --- /dev/null +++ b/third_party/libwebrtc/common_audio/wav_header.cc @@ -0,0 +1,435 @@ +/* + * Copyright (c) 2014 The WebRTC project authors. All Rights Reserved. + * + * Use of this source code is governed by a BSD-style license + * that can be found in the LICENSE file in the root of the source + * tree. An additional intellectual property rights grant can be found + * in the file PATENTS. All contributing project authors may + * be found in the AUTHORS file in the root of the source tree. + */ + +// Based on the WAV file format documentation at +// https://ccrma.stanford.edu/courses/422/projects/WaveFormat/ and +// http://www-mmsp.ece.mcgill.ca/Documents/AudioFormats/WAVE/WAVE.html + +#include "common_audio/wav_header.h" + +#include <cstring> +#include <limits> +#include <string> + +#include "rtc_base/checks.h" +#include "rtc_base/logging.h" +#include "rtc_base/sanitizer.h" +#include "rtc_base/system/arch.h" + +namespace webrtc { +namespace { + +#ifndef WEBRTC_ARCH_LITTLE_ENDIAN +#error "Code not working properly for big endian platforms." +#endif + +#pragma pack(2) +struct ChunkHeader { + uint32_t ID; + uint32_t Size; +}; +static_assert(sizeof(ChunkHeader) == 8, "ChunkHeader size"); + +#pragma pack(2) +struct RiffHeader { + ChunkHeader header; + uint32_t Format; +}; +static_assert(sizeof(RiffHeader) == sizeof(ChunkHeader) + 4, "RiffHeader size"); + +// We can't nest this definition in WavHeader, because VS2013 gives an error +// on sizeof(WavHeader::fmt): "error C2070: 'unknown': illegal sizeof operand". +#pragma pack(2) +struct FmtPcmSubchunk { + ChunkHeader header; + uint16_t AudioFormat; + uint16_t NumChannels; + uint32_t SampleRate; + uint32_t ByteRate; + uint16_t BlockAlign; + uint16_t BitsPerSample; +}; +static_assert(sizeof(FmtPcmSubchunk) == 24, "FmtPcmSubchunk size"); +const uint32_t kFmtPcmSubchunkSize = + sizeof(FmtPcmSubchunk) - sizeof(ChunkHeader); + +// Pack struct to avoid additional padding bytes. +#pragma pack(2) +struct FmtIeeeFloatSubchunk { + ChunkHeader header; + uint16_t AudioFormat; + uint16_t NumChannels; + uint32_t SampleRate; + uint32_t ByteRate; + uint16_t BlockAlign; + uint16_t BitsPerSample; + uint16_t ExtensionSize; +}; +static_assert(sizeof(FmtIeeeFloatSubchunk) == 26, "FmtIeeeFloatSubchunk size"); +const uint32_t kFmtIeeeFloatSubchunkSize = + sizeof(FmtIeeeFloatSubchunk) - sizeof(ChunkHeader); + +// Simple PCM wav header. It does not include chunks that are not essential to +// read audio samples. +#pragma pack(2) +struct WavHeaderPcm { + RiffHeader riff; + FmtPcmSubchunk fmt; + struct { + ChunkHeader header; + } data; +}; +static_assert(sizeof(WavHeaderPcm) == kPcmWavHeaderSize, + "no padding in header"); + +// IEEE Float Wav header, includes extra chunks necessary for proper non-PCM +// WAV implementation. +#pragma pack(2) +struct WavHeaderIeeeFloat { + RiffHeader riff; + FmtIeeeFloatSubchunk fmt; + struct { + ChunkHeader header; + uint32_t SampleLength; + } fact; + struct { + ChunkHeader header; + } data; +}; +static_assert(sizeof(WavHeaderIeeeFloat) == kIeeeFloatWavHeaderSize, + "no padding in header"); + +uint32_t PackFourCC(char a, char b, char c, char d) { + uint32_t packed_value = + static_cast<uint32_t>(a) | static_cast<uint32_t>(b) << 8 | + static_cast<uint32_t>(c) << 16 | static_cast<uint32_t>(d) << 24; + return packed_value; +} + +std::string ReadFourCC(uint32_t x) { + return std::string(reinterpret_cast<char*>(&x), 4); +} + +uint16_t MapWavFormatToHeaderField(WavFormat format) { + switch (format) { + case WavFormat::kWavFormatPcm: + return 1; + case WavFormat::kWavFormatIeeeFloat: + return 3; + case WavFormat::kWavFormatALaw: + return 6; + case WavFormat::kWavFormatMuLaw: + return 7; + } + RTC_CHECK_NOTREACHED(); +} + +WavFormat MapHeaderFieldToWavFormat(uint16_t format_header_value) { + if (format_header_value == 1) { + return WavFormat::kWavFormatPcm; + } + if (format_header_value == 3) { + return WavFormat::kWavFormatIeeeFloat; + } + + RTC_CHECK(false) << "Unsupported WAV format"; +} + +uint32_t RiffChunkSize(size_t bytes_in_payload, size_t header_size) { + return static_cast<uint32_t>(bytes_in_payload + header_size - + sizeof(ChunkHeader)); +} + +uint32_t ByteRate(size_t num_channels, + int sample_rate, + size_t bytes_per_sample) { + return static_cast<uint32_t>(num_channels * sample_rate * bytes_per_sample); +} + +uint16_t BlockAlign(size_t num_channels, size_t bytes_per_sample) { + return static_cast<uint16_t>(num_channels * bytes_per_sample); +} + +// Finds a chunk having the sought ID. If found, then `readable` points to the +// first byte of the sought chunk data. If not found, the end of the file is +// reached. +bool FindWaveChunk(ChunkHeader* chunk_header, + WavHeaderReader* readable, + const std::string sought_chunk_id) { + RTC_DCHECK_EQ(sought_chunk_id.size(), 4); + while (true) { + if (readable->Read(chunk_header, sizeof(*chunk_header)) != + sizeof(*chunk_header)) + return false; // EOF. + if (ReadFourCC(chunk_header->ID) == sought_chunk_id) + return true; // Sought chunk found. + // Ignore current chunk by skipping its payload. + if (!readable->SeekForward(chunk_header->Size)) + return false; // EOF or error. + } +} + +bool ReadFmtChunkData(FmtPcmSubchunk* fmt_subchunk, WavHeaderReader* readable) { + // Reads "fmt " chunk payload. + if (readable->Read(&(fmt_subchunk->AudioFormat), kFmtPcmSubchunkSize) != + kFmtPcmSubchunkSize) + return false; + const uint32_t fmt_size = fmt_subchunk->header.Size; + if (fmt_size != kFmtPcmSubchunkSize) { + // There is an optional two-byte extension field permitted to be present + // with PCM, but which must be zero. + int16_t ext_size; + if (kFmtPcmSubchunkSize + sizeof(ext_size) != fmt_size) + return false; + if (readable->Read(&ext_size, sizeof(ext_size)) != sizeof(ext_size)) + return false; + if (ext_size != 0) + return false; + } + return true; +} + +void WritePcmWavHeader(size_t num_channels, + int sample_rate, + size_t bytes_per_sample, + size_t num_samples, + uint8_t* buf, + size_t* header_size) { + RTC_CHECK(buf); + RTC_CHECK(header_size); + *header_size = kPcmWavHeaderSize; + auto header = rtc::MsanUninitialized<WavHeaderPcm>({}); + const size_t bytes_in_payload = bytes_per_sample * num_samples; + + header.riff.header.ID = PackFourCC('R', 'I', 'F', 'F'); + header.riff.header.Size = RiffChunkSize(bytes_in_payload, *header_size); + header.riff.Format = PackFourCC('W', 'A', 'V', 'E'); + header.fmt.header.ID = PackFourCC('f', 'm', 't', ' '); + header.fmt.header.Size = kFmtPcmSubchunkSize; + header.fmt.AudioFormat = MapWavFormatToHeaderField(WavFormat::kWavFormatPcm); + header.fmt.NumChannels = static_cast<uint16_t>(num_channels); + header.fmt.SampleRate = sample_rate; + header.fmt.ByteRate = ByteRate(num_channels, sample_rate, bytes_per_sample); + header.fmt.BlockAlign = BlockAlign(num_channels, bytes_per_sample); + header.fmt.BitsPerSample = static_cast<uint16_t>(8 * bytes_per_sample); + header.data.header.ID = PackFourCC('d', 'a', 't', 'a'); + header.data.header.Size = static_cast<uint32_t>(bytes_in_payload); + + // Do an extra copy rather than writing everything to buf directly, since buf + // might not be correctly aligned. + memcpy(buf, &header, *header_size); +} + +void WriteIeeeFloatWavHeader(size_t num_channels, + int sample_rate, + size_t bytes_per_sample, + size_t num_samples, + uint8_t* buf, + size_t* header_size) { + RTC_CHECK(buf); + RTC_CHECK(header_size); + *header_size = kIeeeFloatWavHeaderSize; + auto header = rtc::MsanUninitialized<WavHeaderIeeeFloat>({}); + const size_t bytes_in_payload = bytes_per_sample * num_samples; + + header.riff.header.ID = PackFourCC('R', 'I', 'F', 'F'); + header.riff.header.Size = RiffChunkSize(bytes_in_payload, *header_size); + header.riff.Format = PackFourCC('W', 'A', 'V', 'E'); + header.fmt.header.ID = PackFourCC('f', 'm', 't', ' '); + header.fmt.header.Size = kFmtIeeeFloatSubchunkSize; + header.fmt.AudioFormat = + MapWavFormatToHeaderField(WavFormat::kWavFormatIeeeFloat); + header.fmt.NumChannels = static_cast<uint16_t>(num_channels); + header.fmt.SampleRate = sample_rate; + header.fmt.ByteRate = ByteRate(num_channels, sample_rate, bytes_per_sample); + header.fmt.BlockAlign = BlockAlign(num_channels, bytes_per_sample); + header.fmt.BitsPerSample = static_cast<uint16_t>(8 * bytes_per_sample); + header.fmt.ExtensionSize = 0; + header.fact.header.ID = PackFourCC('f', 'a', 'c', 't'); + header.fact.header.Size = 4; + header.fact.SampleLength = static_cast<uint32_t>(num_channels * num_samples); + header.data.header.ID = PackFourCC('d', 'a', 't', 'a'); + header.data.header.Size = static_cast<uint32_t>(bytes_in_payload); + + // Do an extra copy rather than writing everything to buf directly, since buf + // might not be correctly aligned. + memcpy(buf, &header, *header_size); +} + +// Returns the number of bytes per sample for the format. +size_t GetFormatBytesPerSample(WavFormat format) { + switch (format) { + case WavFormat::kWavFormatPcm: + // Other values may be OK, but for now we're conservative. + return 2; + case WavFormat::kWavFormatALaw: + case WavFormat::kWavFormatMuLaw: + return 1; + case WavFormat::kWavFormatIeeeFloat: + return 4; + } + RTC_CHECK_NOTREACHED(); +} + +bool CheckWavParameters(size_t num_channels, + int sample_rate, + WavFormat format, + size_t bytes_per_sample, + size_t num_samples) { + // num_channels, sample_rate, and bytes_per_sample must be positive, must fit + // in their respective fields, and their product must fit in the 32-bit + // ByteRate field. + if (num_channels == 0 || sample_rate <= 0 || bytes_per_sample == 0) + return false; + if (static_cast<uint64_t>(sample_rate) > std::numeric_limits<uint32_t>::max()) + return false; + if (num_channels > std::numeric_limits<uint16_t>::max()) + return false; + if (static_cast<uint64_t>(bytes_per_sample) * 8 > + std::numeric_limits<uint16_t>::max()) + return false; + if (static_cast<uint64_t>(sample_rate) * num_channels * bytes_per_sample > + std::numeric_limits<uint32_t>::max()) + return false; + + // format and bytes_per_sample must agree. + switch (format) { + case WavFormat::kWavFormatPcm: + // Other values may be OK, but for now we're conservative: + if (bytes_per_sample != 1 && bytes_per_sample != 2) + return false; + break; + case WavFormat::kWavFormatALaw: + case WavFormat::kWavFormatMuLaw: + if (bytes_per_sample != 1) + return false; + break; + case WavFormat::kWavFormatIeeeFloat: + if (bytes_per_sample != 4) + return false; + break; + default: + return false; + } + + // The number of bytes in the file, not counting the first ChunkHeader, must + // be less than 2^32; otherwise, the ChunkSize field overflows. + const size_t header_size = kPcmWavHeaderSize - sizeof(ChunkHeader); + const size_t max_samples = + (std::numeric_limits<uint32_t>::max() - header_size) / bytes_per_sample; + if (num_samples > max_samples) + return false; + + // Each channel must have the same number of samples. + if (num_samples % num_channels != 0) + return false; + + return true; +} + +} // namespace + +bool CheckWavParameters(size_t num_channels, + int sample_rate, + WavFormat format, + size_t num_samples) { + return CheckWavParameters(num_channels, sample_rate, format, + GetFormatBytesPerSample(format), num_samples); +} + +void WriteWavHeader(size_t num_channels, + int sample_rate, + WavFormat format, + size_t num_samples, + uint8_t* buf, + size_t* header_size) { + RTC_CHECK(buf); + RTC_CHECK(header_size); + + const size_t bytes_per_sample = GetFormatBytesPerSample(format); + RTC_CHECK(CheckWavParameters(num_channels, sample_rate, format, + bytes_per_sample, num_samples)); + if (format == WavFormat::kWavFormatPcm) { + WritePcmWavHeader(num_channels, sample_rate, bytes_per_sample, num_samples, + buf, header_size); + } else { + RTC_CHECK_EQ(format, WavFormat::kWavFormatIeeeFloat); + WriteIeeeFloatWavHeader(num_channels, sample_rate, bytes_per_sample, + num_samples, buf, header_size); + } +} + +bool ReadWavHeader(WavHeaderReader* readable, + size_t* num_channels, + int* sample_rate, + WavFormat* format, + size_t* bytes_per_sample, + size_t* num_samples, + int64_t* data_start_pos) { + // Read using the PCM header, even though it might be float Wav file + auto header = rtc::MsanUninitialized<WavHeaderPcm>({}); + + // Read RIFF chunk. + if (readable->Read(&header.riff, sizeof(header.riff)) != sizeof(header.riff)) + return false; + if (ReadFourCC(header.riff.header.ID) != "RIFF") + return false; + if (ReadFourCC(header.riff.Format) != "WAVE") + return false; + + // Find "fmt " and "data" chunks. While the official Wave file specification + // does not put requirements on the chunks order, it is uncommon to find the + // "data" chunk before the "fmt " one. The code below fails if this is not the + // case. + if (!FindWaveChunk(&header.fmt.header, readable, "fmt ")) { + RTC_LOG(LS_ERROR) << "Cannot find 'fmt ' chunk."; + return false; + } + if (!ReadFmtChunkData(&header.fmt, readable)) { + RTC_LOG(LS_ERROR) << "Cannot read 'fmt ' chunk."; + return false; + } + if (!FindWaveChunk(&header.data.header, readable, "data")) { + RTC_LOG(LS_ERROR) << "Cannot find 'data' chunk."; + return false; + } + + // Parse needed fields. + *format = MapHeaderFieldToWavFormat(header.fmt.AudioFormat); + *num_channels = header.fmt.NumChannels; + *sample_rate = header.fmt.SampleRate; + *bytes_per_sample = header.fmt.BitsPerSample / 8; + const size_t bytes_in_payload = header.data.header.Size; + if (*bytes_per_sample == 0) + return false; + *num_samples = bytes_in_payload / *bytes_per_sample; + + const size_t header_size = *format == WavFormat::kWavFormatPcm + ? kPcmWavHeaderSize + : kIeeeFloatWavHeaderSize; + + if (header.riff.header.Size < RiffChunkSize(bytes_in_payload, header_size)) + return false; + if (header.fmt.ByteRate != + ByteRate(*num_channels, *sample_rate, *bytes_per_sample)) + return false; + if (header.fmt.BlockAlign != BlockAlign(*num_channels, *bytes_per_sample)) + return false; + + if (!CheckWavParameters(*num_channels, *sample_rate, *format, + *bytes_per_sample, *num_samples)) { + return false; + } + + *data_start_pos = readable->GetPosition(); + return true; +} + +} // namespace webrtc |