code: public static Codec getDecoderByName(String avCodecName) throws JavaAVException {
  		if (avCodecName == null || avCodecName.isEmpty())
  			throw new NullPointerException("Codec name is null or empty.");
  
  		AVCodec avCodec = avcodec_find_decoder_by_name(avCodecName);
  
  		if (avCodec == null || avCodec.isNull())
  			throw new JavaAVException("Decoder not found: " + avCodecName);
  
  		Codec codec = new Codec();
  		codec.avCodec = avCodec;
  
  		return codec;
  	}
docs: Create a new decoder with specified codec name.
  
  @param avCodecName the codec name.
  
  @return a new decoder.
  
  @throws JavaAVException if decoder could not be created.