通过 C# 转换图像文件
转换图像格式、元文件、WebP、Svg、Apng 以构建基于 .NET 的跨平台高级图像处理应用程序。
.NET Image API 为程序员提供了高级图像处理和渲染功能。开发人员可以集成它来将光栅和矢量图像,包括照片和图片转换为 PSD、PDF、GIF、PNG、DICOM、SVG、JPG、JPEG2000、APNG、BMP、TIFF、HTML5 CANVAS、WEBP、WMF、EMF 和其他图像格式. API 不仅处理文件转换,还处理将图像转换为黑白和灰度,转换 GIF 图像层等等。
将图像转换为位图 BMP、JPG、PNG
使用 C# Image API,Inter 格式转换就像更改所需格式的扩展名一样简单。以下是一些通用案例,例如image to bmp、image to jpg、image to png,开发人员可以轻松地针对他们的特定格式进行增强。过程是通过 Image.Load 加载源图像。为任何特定设置创建目标 图像格式选项 的对象。最后调用 保存方法 ,通过传递带有路径和保存选项的目标文件作为参数。
图像相互转换的 C# 代码
using Aspose.Imaging; | |
using Aspose.Imaging.FileFormats.Png; | |
using Aspose.Imaging.ImageOptions; | |
using System.Collections.Generic; | |
using System.IO; | |
using System.Linq; | |
string templatesFolder = @"c:\Users\USER\Downloads\templates\"; | |
string dataDir = templatesFolder; | |
ProcessConvertion(); | |
void ProcessConvertion() | |
{ | |
//Get list of supported formats in | |
//Aspose.Imaging for loading and saving images | |
var formats = GetAvailableImageFormats(); | |
var importFormats = formats.Import; | |
var exportFormats = formats.Export; | |
//Process each raster and vector format that can be loaded | |
foreach (var format in importFormats) | |
{ | |
string formatExt = format.Key; | |
var inputFile = Path.Combine(templatesFolder, $"template.{formatExt}"); | |
//Process each raster and vector format | |
//to which we can save imported image | |
foreach (var exportFormat in exportFormats) | |
{ | |
var outputFile = Path.Combine(templatesFolder, $"convert-{formatExt}-to-{exportFormat.Key}.{exportFormat.Key}"); | |
System.Console.WriteLine("Processing conversion:" + outputFile); | |
//More about load method can be found at | |
//https://apireference.aspose.com/imaging/net/aspose.imaging.image/load/methods/2 | |
//Load imported image | |
using (var image = Image.Load(inputFile)) | |
{ | |
//Obtain default saving options defined for each image | |
ImageOptionsBase exportOptions = exportFormat.Value.Clone(); | |
//If loaded image is vector, need to specify vector rasterization options | |
//for export to another vector | |
if (image is VectorImage) | |
{ | |
VectorRasterizationOptions rasterizationOptions = format.Value; | |
rasterizationOptions.PageWidth = image.Width; | |
rasterizationOptions.PageHeight = image.Height; | |
exportOptions.VectorRasterizationOptions = rasterizationOptions; | |
} | |
image.Save(outputFile, exportOptions); | |
} | |
File.Delete(outputFile); | |
} | |
//System.GC.Collect(); | |
} | |
} | |
(Dictionary<string, VectorRasterizationOptions> Import, Dictionary<string, ImageOptionsBase> Export) GetAvailableImageFormats() | |
{ | |
//////////////////////////////// | |
///Raster and vector formats to that we can export images | |
//////////////////////////////// | |
//Raster image formats that support both - save and load and their default save options | |
Dictionary<string, ImageOptionsBase> rasterFormatsThatSupportExportAndImport = new Dictionary<string, ImageOptionsBase>() | |
{ | |
{ "bmp", new BmpOptions()}, | |
{ "gif", new GifOptions()}, | |
{ "dicom", new DicomOptions()}, | |
{ "jpg", new JpegOptions()}, | |
{ "jpeg", new JpegOptions()}, | |
{ "jpeg2000", new Jpeg2000Options() }, | |
{ "j2k", new Jpeg2000Options { Codec = Aspose.Imaging.FileFormats.Jpeg2000.Jpeg2000Codec.J2K } }, | |
{ "jp2", new Jpeg2000Options { Codec = Aspose.Imaging.FileFormats.Jpeg2000.Jpeg2000Codec.Jp2 }}, | |
{ "png",new PngOptions(){ ColorType = PngColorType.TruecolorWithAlpha} }, | |
{ "apng", new ApngOptions()}, | |
{ "tiff", new Aspose.Imaging.ImageOptions.TiffOptions(Aspose.Imaging.FileFormats.Tiff.Enums.TiffExpectedFormat.Default)}, | |
{ "tif", new Aspose.Imaging.ImageOptions.TiffOptions(Aspose.Imaging.FileFormats.Tiff.Enums.TiffExpectedFormat.Default)}, | |
{ "tga", new TgaOptions()}, | |
{ "webp", new WebPOptions()}, | |
{ "ico", new IcoOptions()} | |
}; | |
//Vector image formats that support both - save and load, their default save options | |
//and their rasterization options when exporting to another vector image | |
Dictionary<string, (ImageOptionsBase, VectorRasterizationOptions)> vectorFormatsThatSupportExportAndImport | |
= new Dictionary<string, (ImageOptionsBase, VectorRasterizationOptions)>() | |
{ | |
{ "emf", (new EmfOptions(),new EmfRasterizationOptions()) }, | |
{ "svg", (new SvgOptions(), new SvgRasterizationOptions())}, | |
{ "wmf", (new WmfOptions(), new WmfRasterizationOptions())}, | |
{ "emz", (new Aspose.Imaging.ImageOptions.EmfOptions(){ Compress = true }, new EmfRasterizationOptions())}, | |
{ "wmz", (new Aspose.Imaging.ImageOptions.WmfOptions(){ Compress = true }, new WmfRasterizationOptions())}, | |
{ "svgz", (new Aspose.Imaging.ImageOptions.SvgOptions(){ Compress = true }, new SvgRasterizationOptions())}, | |
}; | |
//////////////////////////////// | |
///Raster and vector formats from which we can load images | |
//////////////////////////////// | |
//Formats that can be only saved (supported only save to this formats) | |
Dictionary<string, ImageOptionsBase> formatsOnlyForExport = new Dictionary<string, ImageOptionsBase>() | |
{ | |
{ "psd", new PsdOptions()}, | |
{ "dxf", new DxfOptions(){ TextAsLines = true,ConvertTextBeziers = true} }, | |
{ "pdf", new PdfOptions()}, | |
{ "html", new Html5CanvasOptions()}, | |
}; | |
//Raster formats that can be only loaded | |
List<string> formatsOnlyForImport = new List<string>() | |
{ | |
"djvu", "dng", "dib" | |
}; | |
//Vector formats only for loading and their rasterization options when exporting to another vector format | |
Dictionary<string, VectorRasterizationOptions> vectorFormatsOnlyForImport = new Dictionary<string, VectorRasterizationOptions>() | |
{ | |
{"eps", new EpsRasterizationOptions()}, | |
{"cdr", new CdrRasterizationOptions() }, | |
{"cmx", new CmxRasterizationOptions() }, | |
{"otg", new OtgRasterizationOptions() }, | |
{"odg", new OdgRasterizationOptions() } | |
}; | |
//Get total set of formats to what we can export images | |
Dictionary<string, ImageOptionsBase> exportFormats = vectorFormatsThatSupportExportAndImport | |
.ToDictionary(s => s.Key, s => s.Value.Item1) | |
.Union(formatsOnlyForExport) | |
.Concat(rasterFormatsThatSupportExportAndImport) | |
.ToDictionary(s => s.Key, s => s.Value); | |
//Get total set of formats that can be loaded | |
Dictionary<string, VectorRasterizationOptions> importFormats = vectorFormatsOnlyForImport | |
.Union(formatsOnlyForImport.ToDictionary(s => s, s => new VectorRasterizationOptions())) | |
.Union(vectorFormatsThatSupportExportAndImport.ToDictionary(s => s.Key, s => s.Value.Item2)) | |
.ToDictionary(s => s.Key, s => s.Value); | |
return (Import: importFormats, Export: exportFormats); | |
} |
光栅图像到 PDF 转换
将光栅图像转换为 PDF 的过程与图像相互转换的过程相同,只是 API 为特定的 PDF 设置提供了 PdfOptions .程序员可以根据他们的特定需求轻松地对其进行增强。
光栅图像到 PDF 转换的代码
using (Image imge = Image.Load(dataDir+ "transparent_orig.gif")) | |
{ | |
imge.Save(dataDir+"output.pdf", new PdfOptions() { PdfDocumentInfo = new Aspose.Imaging.FileFormats.Pdf.PdfDocumentInfo() } ); | |
} |
将 SVG 转换为光栅图像 BMP、PNG、JPG
SVG的转换过程是一样的,加载SVG文件,使用相关的图片保存选项,调用Save方法。 Image API 提供 SvgRasterizationOptions 用于设置 PageWidth、PageHeight 和光栅图像,使用它们的 VectorRasterizationOptions 属性进行初始化和获取 SvgRasterizationOptions 选项。
用于 SVG 到光栅图像的 C# 代码
// Load the image | |
using (SvgImage image = (SvgImage)Image.Load(dataDir + "sourceFile.Svg")) | |
{ | |
// Create an instance of relevant raster image options and Save the results to disk | |
PngOptions pngOptions = new PngOptions(); | |
SvgRasterizationOptions svgOptions = new SvgRasterizationOptions(); | |
svgOptions.PageWidth = 100; | |
svgOptions.PageHeight = 200; | |
pngOptions.VectorRasterizationOptions = svgOptions; | |
image.Save(dataDir + "ConvertingSVGToRasterImages_out.png", pngOptions); | |
} |
所有支持的图像格式转换
下面是完整的图像格式列表,您可以将其转换为:
要转换为的所有支持的图像格式
下面是完整的图像格式列表,您可以从中进行转换: