public override List <DCMAbstractType> Decode(byte[] data, ref uint idx)
{
//a) 用ExplicitVRLittleEndian对象实例化filemeta对象，通过其Decode方法从data中读取头元素
filemeta = new DCMFileMeta(new ExplicitVRLittleEndian());
filemeta.Decode(data, ref idx);
//b) 读取(0002,0010)头元素
DCMAbstractType head = filemeta.items.Find(x => ((x.gtag == 0x0002) && (x.etag == 0x0010)));
//得到数据集传输语法的uid，
String uid = head.GetValue <string>();
//在TransferSyntaxes中找到对应的传输语法对象赋给基类的syn字段
base.syn = TransferSyntaxs.All[uid];
//c) 调用base.Decode方法解码数据集。
return(base.Decode(data, ref idx));
}
public override List <DCMAbstractType> Decode(byte[] data, ref uint idx)
{
DCMAbstractType elem = syn.Decode(data, ref idx);
if (elem.gtag == 0x0002 && elem.etag == 0x0000)
{
uint ulidx = 0;
int glen = (int)elem.GetValue <UInt32>();
byte[] val = new byte[glen];
Array.Copy(data, idx, val, 0, glen);
base.Decode(val, ref ulidx);
idx += ulidx;
}
return(items);
}
public override List <DCMAbstractType> Decode(byte[] data, ref uint idx)
{
DCMAbstractType item = syn.Decode(data, ref idx);
if (item.gtag == 0xfffe && item.etag == 0xe000) //item start
{
uint ulidx = 0;
byte[] val = (byte[])item.value;
base.Decode(val, ref ulidx);
//todo：修正idx位置
if (item.length == 0xffffffff) //修正idx位置
{
idx -= (uint)(val.Length - ulidx);
}
}
return(base.items);
}
/// <param name="data">数据流</param>
/// <param name="idx">位置索引</param>
public virtual List <DCMAbstractType> Decode(byte[] data, ref uint idx)
{
items = new List <DCMAbstractType>();
while (idx < data.Length)
{
DCMAbstractType item = null;
//此处调用传输语法对象解码一条数据元素
item = syn.Decode(data, ref idx);
//判断特殊标记
if (item.gtag == 0xfffe && item.etag == 0xe0dd)
{
break;
}
if (item.gtag == 0xfffe && item.etag == 0xe00d)
{
break;
}
if (item.vr == "SQ")
{
DCMDataSequence sq = new DCMDataSequence(syn);
uint ulidx = 0;
byte[] val = (byte[])item.value;
sq.Decode(val, ref ulidx);
item.value = sq;
//todo：修正idx位置
if (item.length == 0xffffffff) //修正idx位置
{
idx -= (uint)(val.Length - ulidx);
}
}
Console.WriteLine(idx);
items.Add(item);
}
return(items);
}