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LibAudio: Use new generic seek table for MP3

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MP3 had the exact same data structure, except less readable and less
efficient.
This commit is contained in:
kleines Filmröllchen 2023-03-18 14:23:39 +01:00 • committed by Linus Groh
parent 0cd0565abc
commit 27d9ed0224
Notes: sideshowbarker 2024-07-17 04:01:41 +09:00
2 changed files with 7 additions and 9 deletions
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14
Userland/Libraries/LibAudio/MP3Loader.cpp
View file

@ -75,12 +75,10 @@ MaybeLoaderError MP3LoaderPlugin::reset()
MaybeLoaderError MP3LoaderPlugin::seek(int const position)
{
for (auto const& seek_entry : m_seek_table) {
if (seek_entry.get<1>() >= position) {
LOADER_TRY(m_stream->seek(seek_entry.get<0>(), SeekMode::SetPosition));
m_loaded_samples = seek_entry.get<1>();
break;
}
auto seek_entry = m_seek_table.seek_point_before(position);
if (seek_entry.has_value()) {
LOADER_TRY(m_stream->seek(seek_entry->byte_offset, SeekMode::SetPosition));
m_loaded_samples = seek_entry->sample_index;
}
m_current_frame = {};
m_synthesis_buffer = {};
@ -135,7 +133,7 @@ MaybeLoaderError MP3LoaderPlugin::build_seek_table()
{
int sample_count = 0;
size_t frame_count = 0;
m_seek_table.clear();
m_seek_table = {};
m_bitstream->align_to_byte_boundary();
@ -150,7 +148,7 @@ MaybeLoaderError MP3LoaderPlugin::build_seek_table()
sample_count += MP3::frame_size;
if (frame_count % 10 == 0)
m_seek_table.append({ frame_pos, sample_count });
LOADER_TRY(m_seek_table.insert_seek_point({ static_cast<u64>(sample_count), frame_pos }));
LOADER_TRY(m_stream->seek(error_or_header.value().frame_size - 6, SeekMode::FromCurrentPosition));

2
Userland/Libraries/LibAudio/MP3Loader.h
View file

@ -57,7 +57,7 @@ private:
static void synthesis(Array<float, 1024>& V, Array<float, 32>& samples, Array<float, 32>& result);
static ReadonlySpan<MP3::Tables::ScaleFactorBand> get_scalefactor_bands(MP3::Granule const&, int samplerate);
AK::Vector<AK::Tuple<size_t, int>> m_seek_table;
SeekTable m_seek_table;
AK::Array<AK::Array<AK::Array<float, 18>, 32>, 2> m_last_values {};
AK::Array<AK::Array<float, 1024>, 2> m_synthesis_buffer {};
static DSP::MDCT<36> s_mdct_36;