fn remix_or_drop_channels()

in src/backend/buffer_manager.rs [58:92]

• 32 lines of code
• 7 McCabe index (conditional complexity)

fn remix_or_drop_channels<T: DataType>(
    input_channels: usize,
    output_channels: usize,
    data: &mut [T],
    frame_count: usize,
) -> usize {
    assert!(input_channels >= output_channels);
    // Nothing to do, just return
    if input_channels == output_channels {
        return output_channels * frame_count;
    }
    // Simple stereo downmix
    if input_channels == 2 && output_channels == 1 {
        let mut read_idx = 0;
        for (write_idx, _) in (0..frame_count).enumerate() {
            let avg = (data[read_idx].as_() + data[read_idx + 1].as_()) / 2.0;
            data[write_idx] = DataType::from_f32(avg);
            read_idx += 2;
        }
        return output_channels * frame_count;
    }
    // Drop excess channels
    let mut read_idx = 0;
    let mut write_idx = 0;
    let channel_dropped_count = input_channels - output_channels;
    for _ in 0..frame_count {
        for _ in 0..output_channels {
            data[write_idx] = data[read_idx];
            write_idx += 1;
            read_idx += 1;
        }
        read_idx += channel_dropped_count;
    }
    output_channels * frame_count
}