wav-codec (#13)

here is a wav decoder, enjoy!

Reviewed-on: https://codeberg.org/cool-tech-zone/tangara-fw/pulls/13
Reviewed-by: cooljqln <cooljqln@noreply.codeberg.org>
Co-authored-by: ailurux <ailuruxx@gmail.com>
Co-committed-by: ailurux <ailuruxx@gmail.com>

.gitignore

@@ -18,3 +18,5 @@ doc/
 test/build/
 test/dependencies.lock
 test/sdkconfig
+sdkconfig.bak
+*.ignore

sdkconfig.common

@@ -40,7 +40,7 @@ CONFIG_SPIRAM_ALLOW_STACK_EXTERNAL_MEMORY=y
 CONFIG_RINGBUF_PLACE_FUNCTIONS_INTO_FLASH=y
 CONFIG_ESP_DEFAULT_CPU_FREQ_MHZ_240=y
 CONFIG_ESP_SYSTEM_PANIC_PRINT_HALT=y
-CONFIG_ESP_MAIN_TASK_STACK_SIZE=10000
+CONFIG_ESP_MAIN_TASK_STACK_SIZE=12000
 CONFIG_ESP_INT_WDT_TIMEOUT_MS=5000
 CONFIG_ESP_TASK_WDT_TIMEOUT_S=10
 CONFIG_ESP_BROWNOUT_DET_LVL_SEL_7=y

src/audio/fatfs_audio_input.cpp

@@ -143,7 +143,7 @@ auto FatfsAudioInput::ContainerToStreamType(database::Container enc)
     case database::Container::kMp3:
       return codecs::StreamType::kMp3;
     case database::Container::kWav:
-      return codecs::StreamType::kPcm;
+      return codecs::StreamType::kWav;
     case database::Container::kOgg:
       return codecs::StreamType::kVorbis;
     case database::Container::kFlac:

src/codecs/CMakeLists.txt

@@ -4,9 +4,9 @@
 
 idf_component_register(
   SRCS "codec.cpp" "mad.cpp" "miniflac.cpp" "opus.cpp" "vorbis.cpp"
-       "source_buffer.cpp" "sample.cpp"
+       "source_buffer.cpp" "sample.cpp" "wav.cpp"
   INCLUDE_DIRS "include"
-  REQUIRES "result" "span" "libmad" "miniflac" "tremor" "opusfile" "memory"
+  REQUIRES "result" "span" "libmad" "miniflac" "tremor" "opusfile" "memory" "util"
        "komihash")
 
 target_compile_options("${COMPONENT_LIB}" PRIVATE ${EXTRA_WARNINGS})

src/codecs/codec.cpp

@@ -14,6 +14,7 @@
 #include "opus.hpp"
 #include "types.hpp"
 #include "vorbis.hpp"
+#include "wav.hpp"
 
 namespace codecs {
 
@@ -21,7 +22,7 @@ auto StreamTypeToString(StreamType t) -> std::string {
   switch (t) {
     case StreamType::kMp3:
       return "Mp3";
-    case StreamType::kPcm:
+    case StreamType::kWav:
       return "Wav";
     case StreamType::kVorbis:
       return "Vorbis";
@@ -44,6 +45,8 @@ auto CreateCodecForType(StreamType type) -> std::optional<ICodec*> {
       return new MiniFlacDecoder();
     case StreamType::kOpus:
       return new XiphOpusDecoder();
+    case StreamType::kWav:
+      return new WavDecoder();
     default:
       return {};
   }

src/codecs/include/codec.hpp

@@ -76,6 +76,8 @@ class ICodec {
     kOutOfInput,
     // Indicates that the data within the input buffer is fatally malformed.
     kMalformedData,
+    // Indicated that the format is unsupported
+    kUnsupportedFormat,
 
     kInternalError,
   };
@@ -88,6 +90,8 @@ class ICodec {
         return "malformed data";
       case Error::kInternalError:
         return "internal error";
+      case Error::kUnsupportedFormat:
+        return "unsupported format";
     }
     return "uhh";
   }

src/codecs/include/sample.hpp

@@ -24,10 +24,6 @@ namespace sample {
 //  3. Monty from Xiph.org reckons it's all you need.
 typedef int16_t Sample;
 
-constexpr auto Clip(int64_t v) -> Sample {
-  return std::clamp<int64_t>(v, INT16_MIN, INT16_MAX);
-}
-
 auto shiftWithDither(int64_t src, uint_fast8_t bits) -> Sample;
 
 constexpr auto FromSigned(int32_t src, uint_fast8_t bits) -> Sample {
@@ -42,7 +38,7 @@ constexpr auto FromSigned(int32_t src, uint_fast8_t bits) -> Sample {
 constexpr auto FromUnsigned(uint32_t src, uint_fast8_t bits) -> Sample {
   // Left-align, then substract the max value / 2 to make the sample centred
   // around zero.
-  return (src << (sizeof(uint16_t) * 8 - bits)) - (~0UL >> 1);
+  return (src << (sizeof(uint16_t) * 8 - bits)) - (INT16_MAX+1);
 }
 
 constexpr auto FromFloat(float src) -> Sample {

src/codecs/include/types.hpp

@@ -12,10 +12,10 @@ namespace codecs {
 
 enum class StreamType {
   kMp3,
-  kPcm,
   kVorbis,
   kFlac,
   kOpus,
+  kWav,
 };
 
 auto StreamTypeToString(StreamType t) -> std::string;

src/codecs/include/wav.hpp

@@ -0,0 +1,57 @@
+/*
+ * Copyright 2023 Daniel <ailuruxx@gmail.com>
+ *
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <memory>
+#include <optional>
+#include <string>
+#include <utility>
+
+#include "sample.hpp"
+#include "source_buffer.hpp"
+
+#include "codec.hpp"
+
+namespace codecs {
+
+static const uint16_t kWaveFormatPCM = 0x0001;
+static const uint16_t kWaveFormatIEEEFloat = 0x0003;
+static const uint16_t kWaveFormatAlaw = 0x0006;
+static const uint16_t kWaveFormatMulaw = 0x0007;
+static const uint16_t kWaveFormatExtensible = 0xFFFE;
+
+class WavDecoder : public ICodec {
+ public:
+  WavDecoder();
+  ~WavDecoder();
+
+  auto OpenStream(std::shared_ptr<IStream> input)
+      -> cpp::result<OutputFormat, Error> override;
+
+  auto DecodeTo(cpp::span<sample::Sample> destination)
+      -> cpp::result<OutputInfo, Error> override;
+
+  auto SeekTo(std::size_t target_sample) -> cpp::result<void, Error> override;
+
+  WavDecoder(const WavDecoder&) = delete;
+  WavDecoder& operator=(const WavDecoder&) = delete;
+
+ private:
+  std::shared_ptr<IStream> input_;
+  SourceBuffer buffer_;
+  uint16_t wave_format_;
+  uint16_t subformat_;
+  OutputFormat output_format_;
+  uint16_t bytes_per_sample_;
+  uint16_t num_channels_;
+
+  auto GetFormat() const -> uint16_t;
+};
+
+}  // namespace codecs

src/codecs/sample.cpp

@@ -21,11 +21,8 @@ auto shiftWithDither(int64_t src, uint_fast8_t bits) -> Sample {
   uint64_t mask = 0xFFFFFFFF;
   mask >>= 32 - bits;
   int64_t noise = static_cast<int32_t>(komirand(&sSeed1, &sSeed2) & mask);
-  // Centre the noise around 0.
+  // Apply to the sample, then shift to 16 bit.
-  noise -= (mask >> 1);
+  return (src + noise) >> bits;
-  // Apply to the sample, then clip and shift to 16 bit.
-  Sample clipped = Clip((src + noise) >> bits);
-  return clipped;
 }
 
 }  // namespace sample

src/codecs/source_buffer.cpp

@@ -62,7 +62,7 @@ auto SourceBuffer::AddBytes(std::function<size_t(cpp::span<std::byte>)> writer)
 auto SourceBuffer::ConsumeBytes(
     std::function<size_t(cpp::span<std::byte>)> reader) -> void {
   size_t bytes_consumed = std::invoke(
-      reader, buffer_.subspan(offset_of_bytes_).first(bytes_in_buffer_));
+      reader, buffer_.subspan(offset_of_bytes_, bytes_in_buffer_));
   assert(bytes_consumed <= bytes_in_buffer_);
 
   bytes_in_buffer_ -= bytes_consumed;

src/codecs/wav.cpp

@@ -0,0 +1,259 @@
+/*
+ * Copyright 2023 Daniel <ailuruxx@gmail.com>
+ *
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+#include "wav.hpp"
+#include <stdint.h>
+#include <sys/_stdint.h>
+
+#include <algorithm>
+#include <cstdlib>
+#include <string>
+
+#include "debug.hpp"
+#include "esp_log.h"
+#include "sample.hpp"
+
+namespace codecs {
+
+[[maybe_unused]] static const char kTag[] = "wav";
+
+static inline auto bytes_to_u16(cpp::span<std::byte const, 2> bytes)
+    -> uint16_t {
+  return (uint16_t)bytes[0] | (uint16_t)bytes[1] << 8;
+}
+
+static inline auto bytes_to_u32(cpp::span<std::byte const, 4> bytes)
+    -> uint32_t {
+  return (uint32_t)bytes[0] | (uint32_t)bytes[1] << 8 |
+         (uint32_t)bytes[2] << 16 | (uint32_t)bytes[3] << 24;
+}
+
+static inline auto bytes_to_str(cpp::span<std::byte const> bytes)
+    -> std::string {
+  return std::string(reinterpret_cast<const char*>(bytes.data()),
+                    bytes.size_bytes());
+}
+
+static int16_t convert_f32_to_16_bit(cpp::span<const std::byte> bytes) {
+  uint64_t val = 0;
+  val = (uint8_t)bytes[3];
+  val = (val << 8) | (uint8_t)bytes[2];
+  val = (val << 8) | (uint8_t)bytes[1];
+  val = (val << 8) | (uint8_t)bytes[0];
+  // Isolate the sign and remove from the value
+  uint64_t sign = val >> 31;
+  val -= (sign << 31);
+  // Isolate the exponent and remove from the value
+  uint64_t exp = (val >> 23);
+  val -= (exp << 23);
+  // Remove old bias and add new bias
+  exp = exp - 127 + 1023;
+  // Reconstruct the bits in the correct order and convert to double
+  uint64_t dval = (sign << 63) + (exp << 52) + (val << 29);
+  double* fval = reinterpret_cast<double*>(&dval);
+  return sample::FromDouble(*fval);
+}
+
+static int16_t convert_to_16_bit(cpp::span<const std::byte> bytes) {
+  int depth = bytes.size();
+  int32_t val = 0;
+  // If 8-bit Assume Unsigned
+  if (depth == 1) {
+    return sample::FromUnsigned((uint8_t)bytes[0], 8);
+  }
+  // Otherwise, build the signed int of the right depth
+  switch (depth) {
+    case 4:
+      val = (uint8_t)bytes[3];
+    case 3:
+      val = (val << 8) | (uint8_t)bytes[2];
+    case 2:
+      val = (val << 8) | (uint8_t)bytes[1];
+    case 1:
+      val = (val << 8) | (uint8_t)bytes[0];
+  }
+  // Convert to sample
+  int16_t result = sample::FromSigned(val, depth * 8);
+  return result;
+}
+
+WavDecoder::WavDecoder() : input_(), buffer_() {}
+
+WavDecoder::~WavDecoder() {}
+
+auto WavDecoder::OpenStream(std::shared_ptr<IStream> input)
+    -> cpp::result<OutputFormat, Error> {
+  input_ = input;
+
+  std::array<std::byte, 255> buf{std::byte{0}};
+  auto size = input->Read(buf);
+  if (size < 44) {
+    return cpp::fail(Error::kOutOfInput);
+  }
+
+  // - check the first 4 bytes = 'RIFF'
+  // - next 4 bytes = file size
+  // - check next 4 bytes = 'WAVE'
+  // - index of 'fmt\0' (i) marks start of fmt data
+  // - i + 4 = size of fmt header (16, 18 or 40)
+  // - i + 8 = format (should be 0x01 for pcm, 0xfffe for
+  // wave_format_exstensible)
+  // - i + 10 = num channels
+  // - i + 12 = sample rate
+  // - i + 16 = byte rate (sample rate * channels * bits per sample / 8)
+  // - i + 20 = sample size (bits per sample * channels / 8)
+  // - i + 22 = bits per sample (2 bytes)
+  // - end of this part, next header we care about is 'data'
+  // - and then the next 4 bytes = 32 bit int = size of data
+
+  auto buffer_span = cpp::span{buf};
+
+  std::string riff = bytes_to_str(buffer_span.subspan(0, 4));
+  if (riff != "RIFF") {
+    ESP_LOGW(kTag, "file is not RIFF");
+    return cpp::fail(Error::kMalformedData);
+  }
+
+  uint32_t file_size = bytes_to_u32(buffer_span.subspan(4, 4)) + 8;
+
+  std::string fmt_header = bytes_to_str(buffer_span.subspan(12, 4));
+  ESP_LOGI(kTag, "fmt header found? %s",
+           (fmt_header.starts_with("fmt")) ? "yes" : "no");
+  if (!fmt_header.starts_with("fmt")) {
+    ESP_LOGW(kTag, "Could not find format chunk");
+    return cpp::fail(Error::kMalformedData);
+  }
+
+  // Size of the fmt header, should be 16, 18 or 40
+  uint32_t fmt_header_size = bytes_to_u32(buffer_span.subspan(16, 4));
+
+  wave_format_ = bytes_to_u16(buffer_span.subspan(20, 2));
+  if (wave_format_ == kWaveFormatPCM) {
+    ESP_LOGD(kTag, "wave format: PCM");
+  } else if (wave_format_ == kWaveFormatExtensible) {
+    ESP_LOGD(kTag, "wave format: extensible");
+  } else if (wave_format_ == kWaveFormatIEEEFloat) {
+    ESP_LOGD(kTag, "wave format: IEEE Float");
+  } else {
+    ESP_LOGW(kTag, "WAVE format not supported");
+    return cpp::fail(Error::kUnsupportedFormat);
+  }
+
+  num_channels_ = bytes_to_u16(buffer_span.subspan(22, 2));
+
+  uint32_t samples_per_second = bytes_to_u32(buffer_span.subspan(24, 4));
+
+  uint32_t avg_bytes_per_second = bytes_to_u32(buffer_span.subspan(28, 4));
+
+  uint16_t block_align = bytes_to_u16(buffer_span.subspan(32, 2));
+
+  bytes_per_sample_ = block_align / num_channels_;
+
+  uint16_t bits_per_sample = bytes_to_u16(buffer_span.subspan(34, 2));
+
+  // find the start of the data chunk
+  std::array<std::byte, 4> data_tag = {std::byte{0x64}, std::byte{0x61},
+                                       std::byte{0x74}, std::byte{0x61}};
+  auto data_loc = std::ranges::search(buffer_span, data_tag);
+  if (data_loc.begin() == buffer_span.end()) {
+    ESP_LOGW(kTag, "Could not find data chunk!");
+    return cpp::fail(Error::kMalformedData);
+  }
+
+  int data_chunk_index = std::distance(buffer_span.begin(), data_loc.begin());
+
+  uint32_t data_chunk_size =
+      bytes_to_u32(buffer_span.subspan(data_chunk_index + 4, 4));
+
+  // calculate number of samples
+  int number_of_samples = data_chunk_size / bytes_per_sample_;
+
+  // extension to the fmt chunk size (0 or 22)
+  uint16_t extension_size = 0;
+  if (wave_format_ == kWaveFormatExtensible) {
+    extension_size = bytes_to_u16(buffer_span.subspan(36, 2));
+  }
+
+  // Parse extension if applicable
+  if (extension_size == 22) {
+    // Valid bits per sample
+    uint16_t valid_bits_per_sample = bytes_to_u16(buffer_span.subspan(38, 2));
+
+    uint32_t speaker_mask = bytes_to_u32(buffer_span.subspan(40, 4));
+
+    // Parse subformat
+    subformat_ = bytes_to_u16(buffer_span.subspan(44, 2));
+    if (!(subformat_ == kWaveFormatPCM ||
+          subformat_ == kWaveFormatIEEEFloat)) {
+      ESP_LOGW(kTag, "WAVE extensible subformat_ not supported");
+      return cpp::fail(Error::kUnsupportedFormat);
+    }
+  }
+
+  // 64 bit float is not implemented yet, make sure we're not letting it through
+  if (GetFormat() == kWaveFormatIEEEFloat && bytes_per_sample_ == 8) {
+    ESP_LOGW(kTag, "WAVE 64-Bit Float not supported");
+    return cpp::fail(Error::kUnsupportedFormat);
+  }
+
+  // Seek track to start of data
+  input->SeekTo(data_chunk_index + 8, IStream::SeekFrom::kStartOfStream);
+
+  output_format_ = {.num_channels = (uint8_t)num_channels_,
+                    .sample_rate_hz = samples_per_second,
+                    .total_samples = number_of_samples};
+
+  return output_format_;
+}
+
+auto WavDecoder::DecodeTo(cpp::span<sample::Sample> output)
+    -> cpp::result<OutputInfo, Error> {
+  bool is_eof = buffer_.Refill(input_.get());
+  size_t samples_written = 0;
+
+  buffer_.ConsumeBytes([&](cpp::span<std::byte> buf) -> size_t {
+    size_t bytes_read = buf.size_bytes();
+    size_t frames_read =
+        bytes_read / bytes_per_sample_ / output_format_.num_channels;
+
+    samples_written =
+        std::min<size_t>(frames_read,
+                         output.size() / output_format_.num_channels) *
+        output_format_.num_channels;
+
+    // For each sample that we're going to write
+    for (size_t i = 0; i < samples_written; i++) {
+      auto data = buf.subspan(i * bytes_per_sample_, bytes_per_sample_);
+      if (GetFormat() == kWaveFormatPCM) {
+        // PCM
+        output[i] = convert_to_16_bit(data);
+      } else if (GetFormat() == kWaveFormatIEEEFloat) {
+        // 32-Bit Float
+        if (bytes_per_sample_ == 4) {
+          output[i] = convert_f32_to_16_bit(data);
+        }
+      }
+    }
+
+    return samples_written * bytes_per_sample_;
+  });
+
+  return OutputInfo{.samples_written = samples_written,
+                    .is_stream_finished = samples_written == 0 && is_eof};
+}
+
+auto WavDecoder::SeekTo(size_t target) -> cpp::result<void, Error> {
+  return {};
+}
+
+auto codecs::WavDecoder::GetFormat() const -> uint16_t {
+  if (wave_format_ == kWaveFormatExtensible) {
+    return subformat_;
+  }
+  return wave_format_;
+}
+
+}  // namespace codecs

src/util/CMakeLists.txt

@@ -2,4 +2,4 @@
 #
 # SPDX-License-Identifier: GPL-3.0-only
 
-idf_component_register(SRCS INCLUDE_DIRS "include" REQUIRES "database")
+idf_component_register(SRCS INCLUDE_DIRS "include" REQUIRES "database" "span")

src/util/include/debug.hpp

@@ -0,0 +1,47 @@
+/*
+ * Copyright 2023 jacqueline <me@jacqueline.id.au>
+ *
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+#pragma once
+
+#include <iomanip>
+#include <ostream>
+
+#include <string>
+#include "span.hpp"
+
+namespace util {
+
+inline std::string format_hex_string(cpp::span<const std::byte> data) {
+  std::ostringstream oss;
+  std::ostringstream ascii_values;
+  int count = 0;
+  for (auto byte : data) {
+    if (count % 16 == 0) {
+      if (ascii_values.str().size() > 0) {
+        oss << "\t|" << ascii_values.str() << "|";
+        // Reset ascii values
+        ascii_values.str("");
+      }
+      oss << std::endl;
+      oss << "0x" << std::uppercase << std::setfill('0') << std::setw(2)
+          << std::hex << count << '\t';
+    } else if (count % 8 == 0) {
+      oss << " ";
+    }
+    int byte_val = (int)byte;
+    oss << "[0x" << std::uppercase << std::setfill('0') << std::setw(2)
+        << std::hex << byte_val << ']';
+    if (byte_val >= 32 && byte_val < 127) {
+      ascii_values << (char)byte;
+    } else {
+      ascii_values << ".";
+    }
+    count++;
+  }
+  return oss.str();
+}
+
+}  // namespace util