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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /third_party/libwebrtc/common_audio/wav_header.cc
parentInitial commit. (diff)
downloadfirefox-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.cc435
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