LibMedia: Add ogg/vorbis support

Technically this supports any ogg/* audio stream, but it was at least
tested successfully on ogg/vorbis :^)

Meta/gn/secondary/Userland/Libraries/LibMedia/BUILD.gn

@@ -8,6 +8,7 @@ shared_library("LibMedia") {
     "Audio/Loader.cpp",
     "Audio/MP3Loader.cpp",
     "Audio/Metadata.cpp",
+    "Audio/OggLoader.cpp",
     "Audio/PlaybackStream.cpp",
     "Audio/QOALoader.cpp",
     "Audio/QOATypes.cpp",

Tests/LibMedia/CMakeLists.txt

@@ -2,6 +2,7 @@ set(TEST_SOURCES
     TestH264Decode.cpp
     TestParseMatroska.cpp
     TestPlaybackStream.cpp
+    TestVorbisDecode.cpp
     TestVP9Decode.cpp
     TestWav.cpp
 )

Tests/LibMedia/TestVorbisDecode.cpp

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2024, Jelle Raaijmakers <jelle@ladybird.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibMedia/Audio/Loader.h>
+#include <LibTest/TestCase.h>
+
+static void run_test(StringView file_name, int const num_samples, int const channels, u32 const rate)
+{
+    constexpr auto format = "Ogg Vorbis (.ogg)";
+    constexpr int bits = 32;
+
+    ByteString in_path = ByteString::formatted("vorbis/{}", file_name);
+
+    auto loader = TRY_OR_FAIL(Audio::Loader::create(in_path));
+
+    EXPECT_EQ(loader->format_name(), format);
+    EXPECT_EQ(loader->sample_rate(), rate);
+    EXPECT_EQ(loader->num_channels(), channels);
+    EXPECT_EQ(loader->bits_per_sample(), bits);
+    EXPECT_EQ(loader->total_samples(), num_samples);
+}
+
+TEST_CASE(44_1Khz_stereo)
+{
+    run_test("44_1Khz_stereo.ogg"sv, 352800, 2, 44100);
+}

Userland/Libraries/LibMedia/Audio/Loader.cpp

@@ -1,12 +1,14 @@
 /*
  * Copyright (c) 2018-2023, the SerenityOS developers.
+ * Copyright (c) 2024, Jelle Raaijmakers <jelle@ladybird.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
-#include "FlacLoader.h"
 #include "Loader.h"
+#include "FlacLoader.h"
 #include "MP3Loader.h"
+#include "OggLoader.h"
 #include "QOALoader.h"
 #include "WavLoader.h"
 #include <AK/TypedTransfer.h>
@@ -29,17 +31,14 @@ struct LoaderPluginInitializer {
     ErrorOr<NonnullOwnPtr<LoaderPlugin>, LoaderError> (*create)(NonnullOwnPtr<SeekableStream>);
 };
 
-#define ENUMERATE_LOADER_PLUGINS    \
-    __ENUMERATE_LOADER_PLUGIN(Wav)  \
-    __ENUMERATE_LOADER_PLUGIN(Flac) \
-    __ENUMERATE_LOADER_PLUGIN(QOA)  \
-    __ENUMERATE_LOADER_PLUGIN(MP3)
-
 static constexpr LoaderPluginInitializer s_initializers[] = {
-#define __ENUMERATE_LOADER_PLUGIN(Type) \
-    { Type##LoaderPlugin::sniff, Type##LoaderPlugin::create },
-    ENUMERATE_LOADER_PLUGINS
-#undef __ENUMERATE_LOADER_PLUGIN
+    { FlacLoaderPlugin::sniff, FlacLoaderPlugin::create },
+    { QOALoaderPlugin::sniff, QOALoaderPlugin::create },
+#ifdef USE_FFMPEG
+    { OggLoaderPlugin::sniff, OggLoaderPlugin::create },
+#endif
+    { WavLoaderPlugin::sniff, WavLoaderPlugin::create },
+    { MP3LoaderPlugin::sniff, MP3LoaderPlugin::create },
 };
 
 ErrorOr<NonnullRefPtr<Loader>, LoaderError> Loader::create(StringView path)

Userland/Libraries/LibMedia/Audio/OggLoader.cpp

@@ -0,0 +1,262 @@
+/*
+ * Copyright (c) 2024, Jelle Raaijmakers <jelle@ladybird.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include "OggLoader.h"
+#include <AK/BitStream.h>
+#include <AK/ScopeGuard.h>
+#include <LibCore/System.h>
+
+namespace Audio {
+
+OggLoaderPlugin::OggLoaderPlugin(NonnullOwnPtr<SeekableStream> stream)
+    : LoaderPlugin(move(stream))
+{
+}
+
+OggLoaderPlugin::~OggLoaderPlugin()
+{
+    av_frame_free(&m_frame);
+    av_packet_free(&m_packet);
+    avcodec_free_context(&m_codec_context);
+    avformat_close_input(&m_format_context);
+    avio_context_free(&m_avio_context);
+    av_free(m_avio_buffer);
+}
+
+ErrorOr<NonnullOwnPtr<LoaderPlugin>, LoaderError> OggLoaderPlugin::create(NonnullOwnPtr<SeekableStream> stream)
+{
+    auto loader = make<OggLoaderPlugin>(move(stream));
+    TRY(loader->initialize());
+    return loader;
+}
+
+MaybeLoaderError OggLoaderPlugin::initialize()
+{
+    m_format_context = avformat_alloc_context();
+    if (m_format_context == nullptr)
+        return LoaderError { LoaderError::Category::IO, "Failed to allocate format context" };
+
+    m_avio_buffer = av_malloc(PAGE_SIZE);
+    if (m_avio_buffer == nullptr)
+        return LoaderError { LoaderError::Category::IO, "Failed to allocate AVIO buffer" };
+
+    // This AVIOContext explains to avformat how to interact with our stream
+    m_avio_context = avio_alloc_context(
+        static_cast<unsigned char*>(m_avio_buffer),
+        PAGE_SIZE,
+        0,
+        m_stream.ptr(),
+        [](void* opaque, u8* buffer, int size) -> int {
+            auto& stream = *static_cast<SeekableStream*>(opaque);
+            AK::Bytes buffer_bytes { buffer, static_cast<size_t>(size) };
+            auto read_bytes_or_error = stream.read_some(buffer_bytes);
+            if (read_bytes_or_error.is_error()) {
+                if (read_bytes_or_error.error().code() == EOF)
+                    return AVERROR_EOF;
+                return AVERROR_UNKNOWN;
+            }
+            return static_cast<int>(read_bytes_or_error.value().size());
+        },
+        nullptr,
+        [](void* opaque, int64_t offset, int origin) -> int64_t {
+            auto& stream = *static_cast<SeekableStream*>(opaque);
+            auto seek_mode_from_whence = [](int origin) -> SeekMode {
+                if (origin == SEEK_CUR)
+                    return SeekMode::FromCurrentPosition;
+                if (origin == SEEK_END)
+                    return SeekMode::FromEndPosition;
+                return SeekMode::SetPosition;
+            };
+            auto offset_or_error = stream.seek(offset, seek_mode_from_whence(origin));
+            if (offset_or_error.is_error())
+                return -EIO;
+            return 0;
+        });
+
+    m_format_context->pb = m_avio_context;
+
+    // Open the stream as an ogg container
+    auto* av_input_format = av_find_input_format("ogg");
+    if (av_input_format == nullptr)
+        return LoaderError { LoaderError::Category::Internal, "Failed to obtain input format" };
+
+    if (avformat_open_input(&m_format_context, nullptr, av_input_format, nullptr) < 0)
+        return LoaderError { LoaderError::Category::IO, "Failed to open input for format parsing" };
+
+    // Find the best stream to play within the container
+    int best_stream_index = av_find_best_stream(m_format_context, AVMediaType::AVMEDIA_TYPE_AUDIO, -1, -1, nullptr, 0);
+    if (best_stream_index < 0)
+        return LoaderError { LoaderError::Category::Format, "Failed to find an audio stream" };
+    m_audio_stream = m_format_context->streams[best_stream_index];
+
+    // Set up the codec to decode the audio stream
+    AVCodec const* codec = avcodec_find_decoder(m_audio_stream->codecpar->codec_id);
+    if (codec == nullptr)
+        return LoaderError { LoaderError::Category::IO, "Failed to find a suitable decoder" };
+
+    m_codec_context = avcodec_alloc_context3(codec);
+    if (m_codec_context == nullptr)
+        return LoaderError { LoaderError::Category::IO, "Failed to allocate the codec context" };
+
+    if (avcodec_parameters_to_context(m_codec_context, m_audio_stream->codecpar) < 0)
+        return LoaderError { LoaderError::Category::IO, "Failed to copy codec parameters" };
+
+    m_codec_context->thread_count = AK::min(static_cast<int>(Core::System::hardware_concurrency()), 4);
+
+    if (avcodec_open2(m_codec_context, codec, nullptr) < 0)
+        return LoaderError { LoaderError::Category::IO, "Failed to open input for decoding" };
+
+    double duration_in_seconds = m_audio_stream->duration * time_base();
+    m_total_samples = AK::round_to<decltype(m_total_samples)>(m_codec_context->sample_rate * duration_in_seconds);
+
+    // Prepare packet and frame buffers
+    m_packet = av_packet_alloc();
+    if (m_packet == nullptr)
+        return LoaderError { LoaderError::Category::IO, "Failed to allocate packet" };
+
+    m_frame = av_frame_alloc();
+    if (m_frame == nullptr)
+        return LoaderError { LoaderError::Category::IO, "Failed to allocate frame" };
+
+    return {};
+}
+
+double OggLoaderPlugin::time_base() const
+{
+    return static_cast<double>(m_audio_stream->time_base.num) / m_audio_stream->time_base.den;
+}
+
+bool OggLoaderPlugin::sniff(SeekableStream& stream)
+{
+    LittleEndianInputBitStream bit_input { MaybeOwned<Stream>(stream) };
+    auto maybe_ogg = bit_input.read_bits<u32>(32);
+    return !maybe_ogg.is_error() && maybe_ogg.value() == 0x5367674F; // "OggS"
+}
+
+static ErrorOr<FixedArray<Sample>> extract_samples_from_frame(AVFrame& frame)
+{
+    size_t number_of_samples = frame.nb_samples;
+#ifdef USE_FFMPEG_CH_LAYOUT
+    size_t number_of_channels = frame.ch_layout.nb_channels;
+#else
+    size_t number_of_channels = frame.channels;
+#endif
+    AVSampleFormat format = static_cast<AVSampleFormat>(frame.format);
+
+    VERIFY(number_of_samples > 0);
+
+    // FIXME: handle number_of_channels > 2
+    if (number_of_channels != 1 && number_of_channels != 2)
+        return Error::from_string_view("Unsupported number of channels"sv);
+
+    // FIXME: handle other formats
+    if (format != AV_SAMPLE_FMT_FLTP)
+        return Error::from_string_view("Unsupported sample format"sv);
+
+    // FIXME: handle non-planar data (this is also implied by *P format(s) above)
+    if (av_sample_fmt_is_planar(format) != 1)
+        return Error::from_string_view("Non-planar sample data is not supported yet"sv);
+
+    auto read_sample = [&](uint8_t* plane, size_t sample) -> float {
+        switch (format) {
+        case AV_SAMPLE_FMT_FLTP:
+            return reinterpret_cast<float*>(plane)[sample];
+        default:
+            VERIFY_NOT_REACHED();
+        }
+    };
+
+    auto samples = TRY(FixedArray<Sample>::create(number_of_samples));
+    for (size_t sample = 0; sample < number_of_samples; ++sample) {
+        if (number_of_channels == 1) {
+            samples.unchecked_at(sample) = Sample { read_sample(frame.extended_data[0], sample) };
+        } else {
+            samples.unchecked_at(sample) = Sample {
+                read_sample(frame.extended_data[0], sample),
+                read_sample(frame.extended_data[1], sample),
+            };
+        }
+    }
+    return samples;
+}
+
+ErrorOr<Vector<FixedArray<Sample>>, LoaderError> OggLoaderPlugin::load_chunks(size_t samples_to_read_from_input)
+{
+    Vector<FixedArray<Sample>> chunks {};
+
+    for (;;) {
+        // Obtain a packet and send it to the decoder
+        if (av_read_frame(m_format_context, m_packet) < 0)
+            return LoaderError { LoaderError::Category::IO, "Failed to read frame" };
+        if (avcodec_send_packet(m_codec_context, m_packet) < 0)
+            return LoaderError { LoaderError::Category::IO, "Failed to send packet" };
+        av_packet_unref(m_packet);
+
+        // Ask the decoder for a new frame. We might not have sent enough data yet
+        auto receive_frame_error = avcodec_receive_frame(m_codec_context, m_frame);
+        if (receive_frame_error == 0) {
+            chunks.append(TRY(extract_samples_from_frame(*m_frame)));
+            m_loaded_samples += m_frame->nb_samples;
+
+            samples_to_read_from_input -= AK::min(samples_to_read_from_input, m_frame->nb_samples);
+            if (samples_to_read_from_input == 0)
+                break;
+            continue;
+        }
+
+        if (receive_frame_error == AVERROR(EAGAIN))
+            continue;
+        if (receive_frame_error == AVERROR_EOF)
+            return Error::from_errno(EOF);
+
+        return LoaderError { LoaderError::Category::IO, "Failed to receive frame" };
+    }
+
+    av_frame_unref(m_frame);
+
+    return chunks;
+}
+
+MaybeLoaderError OggLoaderPlugin::reset()
+{
+    return seek(0);
+}
+
+MaybeLoaderError OggLoaderPlugin::seek(int sample_index)
+{
+    auto sample_position_in_seconds = static_cast<double>(sample_index) / m_codec_context->sample_rate;
+    auto sample_timestamp = AK::round_to<int64_t>(sample_position_in_seconds / time_base());
+
+    if (av_seek_frame(m_format_context, m_audio_stream->index, sample_timestamp, 0) < 0)
+        return LoaderError { LoaderError::Category::IO, "Failed to seek" };
+
+    m_loaded_samples = sample_index;
+    return {};
+}
+
+u32 OggLoaderPlugin::sample_rate()
+{
+    VERIFY(m_codec_context != nullptr);
+    return m_codec_context->sample_rate;
+}
+
+u16 OggLoaderPlugin::num_channels()
+{
+    VERIFY(m_codec_context != nullptr);
+#ifdef USE_FFMPEG_CH_LAYOUT
+    return m_codec_context->ch_layout.nb_channels;
+#else
+    return m_codec_context->channels;
+#endif
+}
+
+PcmSampleFormat OggLoaderPlugin::pcm_format()
+{
+    // FIXME: pcm_format() is unused, always return Float for now
+    return PcmSampleFormat::Float32;
+}
+
+}