diff options
Diffstat (limited to 'Userland/Libraries/LibAudio/FlacLoader.cpp')
| -rw-r--r-- | Userland/Libraries/LibAudio/FlacLoader.cpp | 68 |
1 files changed, 51 insertions, 17 deletions
diff --git a/Userland/Libraries/LibAudio/FlacLoader.cpp b/Userland/Libraries/LibAudio/FlacLoader.cpp index 1f44634fdb..ff146cf52a 100644 --- a/Userland/Libraries/LibAudio/FlacLoader.cpp +++ b/Userland/Libraries/LibAudio/FlacLoader.cpp @@ -19,6 +19,7 @@ #include <AK/UFixedBigInt.h> #include <LibAudio/FlacLoader.h> #include <LibAudio/FlacTypes.h> +#include <LibAudio/GenericTypes.h> #include <LibAudio/LoaderError.h> #include <LibAudio/Resampler.h> #include <LibAudio/VorbisComment.h> @@ -203,12 +204,19 @@ MaybeLoaderError FlacLoaderPlugin::load_seektable(FlacRawMetadataBlock& block) BigEndianInputBitStream seektable_bytes { MaybeOwned<Stream>(memory_stream) }; for (size_t i = 0; i < block.length / 18; ++i) { // 11.14. SEEKPOINT - FlacSeekPoint seekpoint { - .sample_index = LOADER_TRY(seektable_bytes.read_bits<u64>(64)), - .byte_offset = LOADER_TRY(seektable_bytes.read_bits<u64>(64)), - .num_samples = LOADER_TRY(seektable_bytes.read_bits<u16>(16)) + u64 sample_index = LOADER_TRY(seektable_bytes.read_bits<u64>(64)); + u64 byte_offset = LOADER_TRY(seektable_bytes.read_bits<u64>(64)); + // The sample count of a seek point is not relevant to us. + [[maybe_unused]] u16 sample_count = LOADER_TRY(seektable_bytes.read_bits<u16>(16)); + // Placeholder, to be ignored. + if (sample_index == 0xFFFFFFFFFFFFFFFF) + continue; + + SeekPoint seekpoint { + .sample_index = sample_index, + .byte_offset = byte_offset, }; - m_seektable.append(seekpoint); + TRY(m_seektable.insert_seek_point(seekpoint)); } dbgln_if(AFLACLOADER_DEBUG, "Loaded seektable of size {}", m_seektable.size()); return {}; @@ -268,41 +276,57 @@ MaybeLoaderError FlacLoaderPlugin::seek(int int_sample_index) if (sample_index == m_loaded_samples) return {}; - auto maybe_target_seekpoint = m_seektable.last_matching([sample_index](auto& seekpoint) { return seekpoint.sample_index <= sample_index; }); + auto maybe_target_seekpoint = m_seektable.seek_point_before(sample_index); + auto const seek_tolerance = (seek_tolerance_ms * m_sample_rate) / 1000; // No seektable or no fitting entry: Perform normal forward read if (!maybe_target_seekpoint.has_value()) { if (sample_index < m_loaded_samples) { LOADER_TRY(m_stream->seek(m_data_start_location, SeekMode::SetPosition)); m_loaded_samples = 0; } - auto to_read = sample_index - m_loaded_samples; - if (to_read == 0) + if (sample_index - m_loaded_samples == 0) return {}; - dbgln_if(AFLACLOADER_DEBUG, "Seeking {} samples manually", to_read); - (void)TRY(load_chunks(to_read)); + dbgln_if(AFLACLOADER_DEBUG, "Seeking {} samples manually", sample_index - m_loaded_samples); } else { auto target_seekpoint = maybe_target_seekpoint.release_value(); // When a small seek happens, we may already be closer to the target than the seekpoint. if (sample_index - target_seekpoint.sample_index > sample_index - m_loaded_samples) { - dbgln_if(AFLACLOADER_DEBUG, "Close enough to target: seeking {} samples manually", sample_index - m_loaded_samples); - (void)TRY(load_chunks(sample_index - m_loaded_samples)); + dbgln_if(AFLACLOADER_DEBUG, "Close enough to target ({} samples): not seeking", sample_index - m_loaded_samples); return {}; } - dbgln_if(AFLACLOADER_DEBUG, "Seeking to seektable: sample index {}, byte offset {}, sample count {}", target_seekpoint.sample_index, target_seekpoint.byte_offset, target_seekpoint.num_samples); + dbgln_if(AFLACLOADER_DEBUG, "Seeking to seektable: sample index {}, byte offset {}", target_seekpoint.sample_index, target_seekpoint.byte_offset); auto position = target_seekpoint.byte_offset + m_data_start_location; if (m_stream->seek(static_cast<i64>(position), SeekMode::SetPosition).is_error()) return LoaderError { LoaderError::Category::IO, m_loaded_samples, DeprecatedString::formatted("Invalid seek position {}", position) }; - - auto remaining_samples_after_seekpoint = sample_index - m_data_start_location; - if (remaining_samples_after_seekpoint > 0) - (void)TRY(load_chunks(remaining_samples_after_seekpoint)); m_loaded_samples = target_seekpoint.sample_index; } + + // Skip frames until we're within the seek tolerance. + while (sample_index - m_loaded_samples > seek_tolerance) { + (void)TRY(next_frame()); + m_loaded_samples += m_current_frame->sample_count; + } + return {}; } +bool FlacLoaderPlugin::should_insert_seekpoint_at(u64 sample_index) const +{ + auto const max_seekpoint_distance = (maximum_seekpoint_distance_ms * m_sample_rate) / 1000; + auto const seek_tolerance = (seek_tolerance_ms * m_sample_rate) / 1000; + auto const current_seekpoint_distance = m_seektable.seek_point_sample_distance_around(sample_index).value_or(NumericLimits<u64>::max()); + auto const distance_to_previous_seekpoint = sample_index - m_seektable.seek_point_before(sample_index).value_or({ 0, 0 }).sample_index; + + // We insert a seekpoint only under two conditions: + // - The seek points around us are spaced too far for what the loader recommends. + // Prevents inserting too many seek points between pre-loaded seek points. + // - We are so far away from the previous seek point that seeking will become too imprecise if we don't insert a seek point at least here. + // Prevents inserting too many seek points at the end of files without pre-loaded seek points. + return current_seekpoint_distance >= max_seekpoint_distance && distance_to_previous_seekpoint >= seek_tolerance; +} + ErrorOr<Vector<FixedArray<Sample>>, LoaderError> FlacLoaderPlugin::load_chunks(size_t samples_to_read_from_input) { ssize_t remaining_samples = static_cast<ssize_t>(m_total_samples - m_loaded_samples); @@ -333,6 +357,16 @@ LoaderSamples FlacLoaderPlugin::next_frame() } \ } while (0) + auto frame_byte_index = TRY(m_stream->tell()); + auto sample_index = m_loaded_samples; + // Insert a new seek point if we don't have enough here. + if (should_insert_seekpoint_at(sample_index)) { + dbgln_if(AFLACLOADER_DEBUG, "Inserting ad-hoc seek point for sample {} at byte {:x} (seekpoint spacing {} samples)", sample_index, frame_byte_index, m_seektable.seek_point_sample_distance_around(sample_index).value_or(NumericLimits<u64>::max())); + auto maybe_error = m_seektable.insert_seek_point({ .sample_index = sample_index, .byte_offset = frame_byte_index - m_data_start_location }); + if (maybe_error.is_error()) + dbgln("FLAC Warning: Inserting seek point for sample {} failed: {}", sample_index, maybe_error.release_error()); + } + BigEndianInputBitStream bit_stream { MaybeOwned<Stream>(*m_stream) }; // TODO: Check the CRC-16 checksum (and others) by keeping track of read data |