src/codecs/pcm.rs

   1 use formats::*;
   2 use super::*;
   3
   4 struct PCMDecoder { chmap: NAChannelMap }
   5
   6 impl PCMDecoder {
   7     fn new() -> Self {
   8         PCMDecoder { chmap: NAChannelMap::new() }
   9     }
  10 }
  11
  12 const CHMAP_MONO: [NAChannelType; 1] = [NAChannelType::C];
  13 const CHMAP_STEREO: [NAChannelType; 2] = [NAChannelType::L, NAChannelType::R];
  14
  15 fn get_default_chmap(nch: u8) -> NAChannelMap {
  16     let mut chmap = NAChannelMap::new();
  17     match nch {
  18         1 => chmap.add_channels(&CHMAP_MONO),
  19         2 => chmap.add_channels(&CHMAP_STEREO),
  20         _ => (),
  21     }
  22     chmap
  23 }
  24
  25 fn get_duration(ainfo: &NAAudioInfo, duration: Option<u64>, data_size: usize) -> usize {
  26 println!("pcm in {:?}, {}", duration, data_size);
  27     if duration == None {
  28         let size_bits = data_size * 8;
  29         let blk_size = (ainfo.get_channels() as usize) * (ainfo.get_format().get_bits() as usize);
  30         size_bits / blk_size
  31     } else {
  32         duration.unwrap() as usize
  33     }
  34 }
  35
  36 impl NADecoder for PCMDecoder {
  37     fn init(&mut self, info: Rc<NACodecInfo>) -> DecoderResult<()> {
  38         if let NACodecTypeInfo::Audio(ainfo) = info.get_properties() {
  39 println!("got info {}", ainfo);
  40             self.chmap = get_default_chmap(ainfo.get_channels());
  41             if self.chmap.num_channels() == 0 { return Err(DecoderError::InvalidData); }
  42             Ok(())
  43         } else {
  44             Err(DecoderError::InvalidData)
  45         }
  46     }
  47     fn decode(&mut self, pkt: &NAPacket) -> DecoderResult<NAFrameRef> {
  48         let info = pkt.get_stream().get_info();
  49         if let NACodecTypeInfo::Audio(ainfo) = info.get_properties() {
  50             let duration = get_duration(&ainfo, pkt.get_duration(), pkt.get_buffer().len());
  51 println!("duration = {}", duration);
  52             let pktbuf = pkt.get_buffer();
  53             let mut buf: Vec<u8> = Vec::with_capacity(pktbuf.len());
  54             buf.clone_from(&pktbuf);
  55             let abuf = NAAudioBuffer::new_from_buf(ainfo, Rc::new(RefCell::new(buf)), self.chmap.clone());
  56             let mut frm = NAFrame::new_from_pkt(pkt, info, NABufferType::AudioPacked(abuf));
  57             frm.set_keyframe(true);
  58             Ok(Rc::new(RefCell::new(frm)))
  59         } else {
  60             Err(DecoderError::InvalidData)
  61         }
  62     }
  63 }
  64
  65 pub fn get_decoder() -> Box<NADecoder> {
  66     Box::new(PCMDecoder::new())
  67 }