zxing/csharp/MultiFormatReader.cs
srowen d4efd44fb0 New C# port from Suraj Supekar
git-svn-id: https://zxing.googlecode.com/svn/trunk@1202 59b500cc-1b3d-0410-9834-0bbf25fbcc57
2010-02-05 19:52:53 +00:00

175 lines
6 KiB
C#
Executable file

/*
* Copyright 2007 ZXing authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
using System;
using MultiFormatOneDReader = com.google.zxing.oned.MultiFormatOneDReader;
using PDF417Reader = com.google.zxing.pdf417.PDF417Reader;
using QRCodeReader = com.google.zxing.qrcode.QRCodeReader;
using DataMatrixReader = com.google.zxing.datamatrix.DataMatrixReader;
namespace com.google.zxing
{
/// <summary> MultiFormatReader is a convenience class and the main entry point into the library for most uses.
/// By default it attempts to decode all barcode formats that the library supports. Optionally, you
/// can provide a hints object to request different behavior, for example only decoding QR codes.
///
/// </summary>
/// <author> Sean Owen
/// </author>
/// <author> dswitkin@google.com (Daniel Switkin)
/// </author>
/// <author>www.Redivivus.in (suraj.supekar@redivivus.in) - Ported from ZXING Java Source
/// </author>
public sealed class MultiFormatReader : Reader
{
/// <summary> This method adds state to the MultiFormatReader. By setting the hints once, subsequent calls
/// to decodeWithState(image) can reuse the same set of readers without reallocating memory. This
/// is important for performance in continuous scan clients.
///
/// </summary>
/// <param name="hints">The set of hints to use for subsequent calls to decode(image)
/// </param>
public System.Collections.Hashtable Hints
{
set
{
this.hints = value;
bool tryHarder = value != null && value.ContainsKey(DecodeHintType.TRY_HARDER);
System.Collections.ArrayList formats = value == null?null:(System.Collections.ArrayList) value[DecodeHintType.POSSIBLE_FORMATS];
readers = System.Collections.ArrayList.Synchronized(new System.Collections.ArrayList(10));
if (formats != null)
{
bool addOneDReader = formats.Contains(BarcodeFormat.UPC_A) || formats.Contains(BarcodeFormat.UPC_E) || formats.Contains(BarcodeFormat.EAN_13) || formats.Contains(BarcodeFormat.EAN_8) || formats.Contains(BarcodeFormat.CODE_39) || formats.Contains(BarcodeFormat.CODE_128) || formats.Contains(BarcodeFormat.ITF);
// Put 1D readers upfront in "normal" mode
if (addOneDReader && !tryHarder)
{
readers.Add(new MultiFormatOneDReader(value));
}
if (formats.Contains(BarcodeFormat.QR_CODE))
{
readers.Add(new QRCodeReader());
}
if (formats.Contains(BarcodeFormat.DATAMATRIX))
{
readers.Add(new DataMatrixReader());
}
if (formats.Contains(BarcodeFormat.PDF417))
{
readers.Add(new PDF417Reader());
}
// At end in "try harder" mode
if (addOneDReader && tryHarder)
{
readers.Add(new MultiFormatOneDReader(value));
}
}
if ((readers.Count == 0))
{
if (!tryHarder)
{
readers.Add(new MultiFormatOneDReader(value));
}
readers.Add(new QRCodeReader());
// TODO re-enable once Data Matrix is ready
// readers.addElement(new DataMatrixReader());
// TODO: Enable once PDF417 has passed QA
//readers.addElement(new PDF417Reader());
if (tryHarder)
{
readers.Add(new MultiFormatOneDReader(value));
}
}
}
}
private System.Collections.Hashtable hints;
private System.Collections.ArrayList readers;
/// <summary> This version of decode honors the intent of Reader.decode(BinaryBitmap) in that it
/// passes null as a hint to the decoders. However, that makes it inefficient to call repeatedly.
/// Use setHints() followed by decodeWithState() for continuous scan applications.
///
/// </summary>
/// <param name="image">The pixel data to decode
/// </param>
/// <returns> The contents of the image
/// </returns>
/// <throws> ReaderException Any errors which occurred </throws>
public Result decode(BinaryBitmap image)
{
Hints = null;
return decodeInternal(image);
}
/// <summary> Decode an image using the hints provided. Does not honor existing state.
///
/// </summary>
/// <param name="image">The pixel data to decode
/// </param>
/// <param name="hints">The hints to use, clearing the previous state.
/// </param>
/// <returns> The contents of the image
/// </returns>
/// <throws> ReaderException Any errors which occurred </throws>
public Result decode(BinaryBitmap image, System.Collections.Hashtable hints)
{
Hints = hints;
return decodeInternal(image);
}
/// <summary> Decode an image using the state set up by calling setHints() previously. Continuous scan
/// clients will get a <b>large</b> speed increase by using this instead of decode().
///
/// </summary>
/// <param name="image">The pixel data to decode
/// </param>
/// <returns> The contents of the image
/// </returns>
/// <throws> ReaderException Any errors which occurred </throws>
public Result decodeWithState(BinaryBitmap image)
{
// Make sure to set up the default state so we don't crash
if (readers == null)
{
Hints = null;
}
return decodeInternal(image);
}
private Result decodeInternal(BinaryBitmap image)
{
int size = readers.Count;
for (int i = 0; i < size; i++)
{
Reader reader = (Reader) readers[i];
try
{
return reader.decode(image, hints);
}
catch (ReaderException re)
{
// continue
}
}
throw ReaderException.Instance;
}
}
}