private readonly IBarcodeReader barcodeReader;
barcodeReader = new BarcodeReader {
AutoRotate = true,
Options = new DecodingOptions {
TryHarder = true,
PossibleFormats = new List < BarcodeFormat {
BarcodeFormat.AZTEC
}
}
};
currentBitmapForDecoding = new Bitmap(# "F:\Aztec-Code-Scandit.png");
Result result = barcodeReader.Decode(currentBitmapForDecoding);
it working when i read image from physical path.but when i assign current frame
of webcam to currentBitmapForDecoding it unabel to reade Aztec Barcode.pls anyone how help me to read aztec barcode from web cam.i also make frame size small but not work.
Related
I'm using the following code snippet to bind a image url to a image object (used as one element in a ViewCell object).
...
Image Picture = new Image()
{
Aspect = Aspect.AspectFit,
HorizontalOptions = LayoutOptions.StartAndExpand
}; // ImageSource.FromUri(new Uri("sImageUrl")))
Picture.SetBinding(Image.SourceProperty, "sImageUrl");
...
The images in the list, for which I'm using that cell view, are not loading always. I was not able to identify the exact reason for the problem, but I think the problem is the load-process (for loading the images from the url/internet)..
Maybe the problem could be solved by setting the url via new Uri(...) as described in the documentation
var webImage = new Image { Aspect = Aspect.AspectFit };
webImage.Source = ImageSource.FromUri(new Uri("https://xamarin.com/content/images/pages/forms/example-app.png"));
Now my question: is there a workaround for binding a uri object? e.g.
...
Image Picture = new Image()
{
Aspect = Aspect.AspectFit,
HorizontalOptions = LayoutOptions.StartAndExpand
}; // ImageSource.FromUri(new Uri("sImageUrl")))
Picture.SetBinding(Image.SourceProperty, ImageSource.FromUri(new Uri("sImageUrl")));
...
I'm working with xamarin studio (version 6.1.2, build 44, update channel "beta", os x).
Would be great if someone got a tipp.
Thanks a lot,
Alex
after some more trying I found a solution.. I'm not sure if it's a secure / professional way.. But for now, it seems to work.
What I did: I implemented my own class "AsyncSrcImage", derived it from Image and added another bindable property:
public class AsyncSrcImage : Image
{
private static String sDefaultURL = "";
public static readonly BindableProperty AsyncImgUrlProperty = BindableProperty.Create(nameof(AsyncImgUrl), typeof(String), typeof(AsyncSrcImage), sDefaultURL);
public String AsyncImgUrl
{
get { return (String)GetValue(AsyncImgUrlProperty); }
set { SetValue(AsyncImgUrlProperty, value); }
}
}
Additionally I adjusted the rendering process with a custom renderer. There I'm loading the image source via new Uri(...) as described in the documentation:
using Xamarin.Forms.Platform.Android;
using Xamarin.Forms;
using System;
[assembly: ExportRenderer(typeof(AsyncSrcImage), typeof(AsyncSrcImageRenderer))]
public class AsyncSrcImageRenderer : ImageRenderer
{
protected override void OnElementChanged(ElementChangedEventArgs<Image> e)
{
base.OnElementChanged(e);
AsyncSrcImage oImage = (AsyncSrcImage)Element;
if (oImage != null && oImage.AsyncImgUrl != "")
{
oImage.Source = ImageSource.FromUri(new Uri(oImage.AsyncImgUrl));
}
}
}
Maybe that helps other folks ;)
I used Flying Saucer library to convert html to pdf. It used to work fine if the system is connected to internet. But if system is not connected to internet then it is taking around 5 minutes. Is there any parameter through which i can stop itextrenderer to look for images online.
Below is the method i used to convert HTML to PDF :
LOGGER.info("Converting HTML To PDF.");
OutputStream os = null;
try {
os = new FileOutputStream(finalOutputFilePath);
final Document cleanedDocument = HtmlUtil.cleanHTML(finalInputFilePath);
final ITextRenderer renderer = new ITextRenderer();
final String url = new File(finalInputFilePath).toURI().toURL().toString();
renderer.setDocument(cleanedDocument, url);
renderer.layout();
renderer.createPDF(os);
LOGGER.info("HTML is converted To PDF.");
} finally {
if (null != os) {
os.flush();
os.close();
}
}
I'm using iTextSharp to update an image object in a PDF with a modified System.Drawing.Image. How do I properly set the PdfName.COLORSPACE and PdfName.FILTER based on the System.Drawing.Image? I'm not sure which System.Drawing.Image properties can be used for the mappings.
private void SetImageData(PdfImageObject pdfImage, System.Drawing.Image image, byte[] imageData)
{
PRStream imgStream = (PRStream)pdfImage.GetDictionary();
imgStream.Clear();
imgStream.SetData(imageData, false, PRStream.NO_COMPRESSION);
imgStream.Put(PdfName.TYPE, PdfName.XOBJECT);
imgStream.Put(PdfName.SUBTYPE, PdfName.IMAGE);
imgStream.Put(PdfName.WIDTH, new PdfNumber(image.Width));
imgStream.Put(PdfName.HEIGHT, new PdfNumber(image.Height));
imgStream.Put(PdfName.LENGTH, new PdfNumber(imageData.LongLength));
// Not sure how to properly set these entries based on the image properties
imgStream.Put(PdfName.BITSPERCOMPONENT, 8);
imgStream.Put(PdfName.COLORSPACE, PdfName.DEVICERGB);
imgStream.Put(PdfName.FILTER, PdfName.DCTDECODE);
}
I took the advice of Chris Haas and cheated by writing the System.Drawing.Image to a temporary PDF and then read it back out as a PdfImageObject.
using (MemoryStream ms = new MemoryStream())
{
using (iTextSharp.text.Document doc = new iTextSharp.text.Document())
{
using (iTextSharp.text.pdf.PdfWriter writer = iTextSharp.text.pdf.PdfWriter.GetInstance(doc))
{
doc.Open();
iTextSharp.text.Image image = iTextSharp.text.Image.GetInstance(drawingImage, drawingImage.RawFormat);
image.SimplifyColorspace();
doc.Add(image);
doc.Close();
}
}
... code that opens the mem stream with PdfReader and retrieves the image as PdfImageObj...
}
That worked but seemed like allot of side stepping for a cheat. I stepped through the code in the call to doc.Add(image) and found that eventually a PdfImage object was created from the iTextSharp.text.Image object and the PdfImage object contained all the dictionary entries that I needed. So I decided to cut some corners on the original cheat and come up with this as my final solution:
private void SetImageData(PdfImageObject pdfImageObj, byte[] imageData)
{
iTextSharp.text.Image image = iTextSharp.text.Image.GetInstance(imageData);
image.SimplifyColorSpace();
PdfImage tempPdfImage = new PdfImage(image, "TempImg", null);
PRStream imgStream = (PRStream)pdfImageObj.GetDictionary();
imgStream.Clear();
imgStream.SetDataRaw(imageData);
imgStream.Merge(tempPdfImage);
}
I have the following code that generates a pdf into the stream. This works well but i now have the following requirements.
1) make page landscape: Looking at other examples they add the property to the document object. But i'm doing this instream. So how would i add this property?
2) Add page numbers. I need to put items into a grid so that there are x number of rows per page. With a page number at the footer of the page. How can this kind of feature be acheived with Itext sharp.
public static void Create(ICollection<Part> parts, string path)
{
PdfReader reader = new PdfReader(path);
var pageWidth = 500;
byte[] bytes;
using (MemoryStream ms = new MemoryStream())
{
using (PdfStamper stamper = new PdfStamper(reader, ms))
{
PdfContentByte cb = stamper.GetOverContent(1);
//Flush the PdfStamper's buffer
stamper.Close();
//Get the raw bytes of the PDF
bytes = ms.ToArray();
var now = String.Format("{0:d-M-yyyy}", DateTime.Now);
var pdfName = string.Format("{0}_factory_worksheet", now).Replace("%", "").Replace(" ", "_");
var context = HttpContext.Current;
context.Response.ContentType = "application/pdf";
context.Response.AddHeader("content-disposition", "attachment;filename=" + pdfName);
context.Response.Buffer = true;
context.Response.Clear();
context.Response.OutputStream.Write(ms.GetBuffer(), 0, ms.GetBuffer().Length);
context.Response.OutputStream.Flush();
context.Response.End();
}
}
}
I don't really know how you handling it C# but logical flow will be like this:
Use PdfDictionary to rotate content in reader to 90 degree.Assuming your pdf contain multiple pages,
PdfReader reader = new PdfReader(path);
for (int pgCnt=1; pgCnt <= reader.getNumberOfPages(); pgCnt++) {
//Logic to implement rotation & Add Page number
}
To get current rotation(assuming you are using Portrait mode & try to convert it in landscape mode) use int rttnPg = reader.getPageRotation(pgCnt); also get the PdfDictionary of that page pgDctnry=reader.getPageN(i);(I named that variable as pgDctnry)
Now to rotate it in 90 degree use
pgDctnry.put(PdfName.ROTATE, new PdfNumber(rttnPg+90));
Now bind it using PdfStamper as you are currently doing it.Now to add page number get over content(here i named it pgCntntBt) of the current page
pgCntntBt = stamper .getOverContent(pgCnt);
rctPgSz = rdrPgr.getPageSizeWithRotation(pgCnt);
pgCntntBt.beginText();
bfUsed=//Base Font used for text to be displayed.Also set font size pgCntntBt.setFontAndSize(bfUsed,8.2f);
txtPg=String.format(pgTxt+" %d/%d",pgCnt,totPgCnt);
pgCntntBt.showTextAligned(2,txtPg,//Put Width,//Put Height,//Rotation);
pgCntntBt.endText();
Actually i don't understand what you mean by this:"I need to put items into a grid so that there are x number of rows per page. With a page number at the footer of the page".Now close the stamper to flush it in outputstream.
I'm having a problem trying to locate a PdfContentByte directly into an specific page. My problem is: I need to add an Image for each page (That works) and need to add a QRCode to each of the pages at the right bottom corner but this works only for the first Page and I don't know how to repeat it on the other ones.
This is my code:
public string GeneratePDFDocument(Atomic.Development.Montenegro.Data.Entities.Document document, Stamp stamp)
{
string filename = #"C:\Users\Sheldon\Desktop\Pdf.Pdf";
FileStream fs = new FileStream(filename, FileMode.Create);
iTextSharp.text.Document pdfDocument = new iTextSharp.text.Document(PageSize.LETTER, PAGE_LEFT_MARGIN, PAGE_RIGHT_MARGIN, PAGE_TOP_MARGIN, PAGE_BOTTOM_MARGIN);
iTextSharp.text.pdf.PdfWriter writer = iTextSharp.text.pdf.PdfWriter.GetInstance(pdfDocument, fs);
pdfDocument.Open();
int count = document.Pages.Count;
foreach (Page page in document.Pages)
{
Image img = Image.GetInstance(page.Image);
img.ScaleToFit(PageSize.LETTER.Width-(PAGE_LEFT_MARGIN + PAGE_RIGHT_MARGIN), PageSize.LETTER.Height-(PAGE_TOP_MARGIN + PAGE_BOTTOM_MARGIN));
pdfDocument.Add(img);
PlaceCodeBar(writer);
}
pdfDocument.Close();
writer.Close();
fs.Close();
return filename;
}
private static void PlaceCodeBar(iTextSharp.text.pdf.PdfWriter writer)
{
String codeText = "TEXT TO ENCODE";
iTextSharp.text.pdf.BarcodePDF417 pdf417 = new iTextSharp.text.pdf.BarcodePDF417();
pdf417.SetText(codeText);
Image img = pdf417.GetImage();
iTextSharp.text.pdf.BarcodeQRCode qrcode = new iTextSharp.text.pdf.BarcodeQRCode(codeText, 1, 1, null);
img = qrcode.GetImage();
iTextSharp.text.pdf.PdfContentByte cb = writer.DirectContent;
cb.SaveState();
cb.BeginText();
img.SetAbsolutePosition(PageSize.LETTER.Width-PAGE_RIGHT_MARGIN-img.ScaledWidth, PAGE_BOTTOM_MARGIN);
cb.AddImage(img);
cb.EndText();
cb.RestoreState();
}
So add it in your foreach (Page...) loop:
foreach (Page page in document.Pages)
{
Image img = Image.GetInstance(page.Image);
img.ScaleToFit(PageSize.LETTER.Width-(PAGE_LEFT_MARGIN + PAGE_RIGHT_MARGIN), PageSize.LETTER.Height-(PAGE_TOP_MARGIN + PAGE_BOTTOM_MARGIN));
pdfDocument.Add(img);
PlaceCodeBar(writer);
}
If this is a second pass on the same PDF (you've closed it then opened it again), use a PdfStamper rather than a PdfWriter. You can then get the direct content of each page rather than the one direct content that is reused (and reset) for each page.
PS: Drop the BeginText() and EndText() calls. Those operators should only be used when actually drawing text/setting fonts/etc. No line art. No images. The SaveState()/RestoreState() are good though. Definitely keep those.
I just figure out how to solve the problem. Just delete the cb.SaveState() and cb.RestoreState() and it put the image on the page is actually active.