Method ResolveWaveformReader

src/AudioWaveformer.cpp:402–430

Resolve and cache the reader used for waveform extraction (prefer a detached FFmpegReader clone)

// Resolve and cache the reader used for waveform extraction (prefer a detached FFmpegReader clone)
ReaderBase* AudioWaveformer::ResolveWaveformReader() {
	if (source_initialized) {
		return resolved_reader ? resolved_reader : reader;
	}
	source_initialized = true;

	resolved_reader = ResolveSourceReader(reader);

	// Prefer a detached, audio-only FFmpegReader clone so we never mutate the live reader used for preview.
	if (auto ff_reader = dynamic_cast<FFmpegReader*>(resolved_reader)) {
		const Json::Value ff_json = ff_reader->JsonValue();
		const std::string path = ff_json.get("path", "").asString();
		if (!path.empty()) {
			try {
				auto clone = std::make_unique<FFmpegReader>(path, false);
				clone->SetJsonValue(ff_json);
				clone->info.has_video = false; // explicitly audio-only for waveform extraction
				detached_reader = std::move(clone);
				resolved_reader = detached_reader.get();
			} catch (...) {
				// Fall back to using the original reader if cloning fails
				detached_reader.reset();
				resolved_reader = ResolveSourceReader(reader);
			}
		}
	}

	return resolved_reader ? resolved_reader : reader;
}