Flac Encoder

Purpose and scope: The FLAC encoder converts PCM input into FLAC while preserving lossless quality for archival, distribution, and production workflows. Target users include audio engineers, software developers, and researchers who require repeatable, metadata-friendly encoding in automated pipelines. Use cases include converting WAV/PCM to FLAC for distribution, archiving masters, or integrating encoding into build scripts.
Core logic and features: The tool implements a lossless FLAC encoder with both required and advanced options. Required inputs include source_audio (PCM WAV/RAW), sample_rate (Hz), channels (1 or 2), and bits_per_sample (16 or 24). Optional/advanced inputs include compression_level (0–8), block_size, verify_checksum, and metadata_tags. Outputs include flac_file (binary), duration_sec, sample_rate_out, channels_out, bits_per_sample_out, and size_bytes. It supports batch processing pipelines and metadata enrichment via Vorbis comments.
Inputs and outputs: Inputs cover source_audio (file/blob), sample_rate, channels, bits_per_sample, compression_level, and metadata_tags. Outputs provide a FLAC file with duration, sample_rate_out, channels_out, bits_per_sample_out, and file size. Algorithms & calculations: Encoding follows the FLAC standard: decode PCM input, apply lossless compression at the selected level, and write a FLAC stream with proper stream info and metadata. Duration is computed from input sample count and the sample_rate. Bitrate is reported as an approximate range depending on compression_level and input content.
Error handling and edge cases: Invalid or non-PCM input triggers domain errors; missing required inputs, unsupported sample rates, or incompatible bit depth generate precise error codes. Large files are chunk-processed with integrity checks when verify_checksum is enabled. Industry standards: FLAC files use .flac extension and 16- or 24-bit PCM; localization considerations include language-neutral metadata fields and Vorbis comments support. Assumptions & Exclusions: Assumes input is PCM linear audio; does not transcode to lossy formats, perform streaming encoding, or modify non-audio data.