public static string EncodeFromStream(
Stream stream
)
stream
Stream containing an image file. Supported image formats are PNG, GIF and JPEG. All other image formats will result in an error.
A data URI string containing the media type, encoding and image data encoded as base 64.
Refer to Parse for more information about data URIs.
Use EncodeFromFile to create a standard data URI from a file.
using Leadtools;
using Leadtools.Codecs;
using Leadtools.Drawing;
using Leadtools.Forms.DocumentWriters;
using Leadtools.Svg;
using Leadtools.Document.Writer;
private static void SvgDocumentEnumerateElementsExample()
{
// The source PDF file
var sourceFile = $@"{LEAD_VARS.ImagesDir}\Leadtools.pdf";
var beforeSvgFile = $@"{LEAD_VARS.ImagesDir}\Leadtools_before.svg";
var afterSvgFile = $@"{LEAD_VARS.ImagesDir}\Leadtools_after.svg";
// Assume this is our Virtual Directory
var virtualDirectory = "http://localhost/leadtools_images/svg/resources";
// Assume this phrysical directory maps to the Virtual Directory
var physicalDirectory = $@"{LEAD_VARS.ImagesDir}\svg\resources";
if (!Directory.Exists(physicalDirectory))
Directory.CreateDirectory(physicalDirectory);
// Our SVG element enumartion callback
SvgEnumerateElementsCallback callback = (SvgDocument document, SvgNodeHandle node, object userData) =>
{
if (node.ElementType == SvgElementType.Image)
{
// Get the href
var href = node.GetAttributeValue("xlink:href");
if (!string.IsNullOrEmpty(href))
{
// Parse it as data URI
var dataUri = SvgDataUri.Parse(href);
// Check if it is a data URI
if (dataUri.IsDataUri)
{
// Yes, create a new file in a virtual directory
// Show the dataURI properties
Console.WriteLine("Replacing data URI");
Console.WriteLine("Format:" + dataUri.ImageFormat);
if (dataUri.MediaLength > 0)
Console.WriteLine("Media:" + dataUri.Href.Substring(dataUri.MediaOffset, dataUri.MediaLength));
if (dataUri.CharSetOffset > 0)
Console.WriteLine("CharSet:" + dataUri.Href.Substring(dataUri.CharSetOffset, dataUri.CharSetLength));
else
Console.WriteLine("CharSet: not set");
Console.WriteLine("IsBase64:" + dataUri.IsBase64);
Console.WriteLine("ImageFormat:" + dataUri.ImageFormat);
var extension = dataUri.Extension;
Console.WriteLine("Extension:" + dataUri.Extension);
// Get a file name
var name = Guid.NewGuid().ToString().Replace("-", "") + "." + dataUri.Extension;
// Save it
// Full physical path
var filePath = Path.Combine(physicalDirectory, name);
dataUri.DecodeToFile(filePath);
/* Alternatively you can save the data yourself using this code
var data = dataUri.Href.Substring(dataUri.ValueOffset, dataUri.ValueLength);
// Save the data
var base64String = dataUri.Href.Substring(dataUri.ValueOffset, dataUri.ValueLength);
byte[] rawData = Convert.FromBase64String(base64String);
// Save it to disk
File.WriteAllBytes(filePath, rawData);
*/
// Finally replace the attribute in the image element with the URI
var virtualPath = virtualDirectory + "/" + name;
node.SetAttributeValue("xlink:href", virtualPath);
}
else
{
Console.WriteLine("Does not contain a valid data URI.");
}
}
}
return true;
};
using (var rasterCodecs = new RasterCodecs())
{
// Use 300 DPI when loading document images
rasterCodecs.Options.RasterizeDocument.Load.Resolution = 300;
// Load the first page as SVG
using (var svg = rasterCodecs.LoadSvg(sourceFile, 1, null) as SvgDocument)
{
if (!svg.IsFlat)
svg.Flat(null);
if (!svg.Bounds.IsValid)
svg.CalculateBounds(false);
// Save this SVG to disk, report the size
svg.SaveToFile(beforeSvgFile, null);
Console.WriteLine("Before unembedding the image, size is " + new FileInfo(beforeSvgFile).Length);
// Now enumerate the elements to replace each embedded image with a URL
// Since we are going to modify the SVG, call BeginUpdate/EndUpdate to speed up the process
svg.BeginUpdate();
svg.EnumerateElements(new SvgEnumerateOptions { EnumerateDirection = SvgEnumerateDirection.TopToBottom }, callback, null);
svg.EndUpdate();
// Save this SVG to disk again, report the size, should be alot smaller since the image are unembedded and stored as external resources
svg.SaveToFile(afterSvgFile, null);
Console.WriteLine("Before unembedding the image, size is " + new FileInfo(afterSvgFile).Length);
}
}
}
static class LEAD_VARS
{
public const string ImagesDir = @"C:\LEADTOOLS23\Resources\Images";
}