C# How to reduce the size of the stream (image) - c#

All I have is the Stream of the file (the file is image/jpeg type). I want to reduce the quality of the image (example: original 2MB -> 200KB).
var contentStream = ImageSource.FromStream(() => { return _MediaFile.GetStream(); });
newImg.Source = contentStream;
_ReportModel.Add(new ReportPicture()
{
Id = layout.Id,
Path = _MediaFile.Path,
Content = _MediaFile.GetStream()
});
Before I upload the _ReportModel to my server using REST API, I want to reduce the size of the Content which contains the stream of the read image (type jpeg).
I need something like:
private Stream ReduceStreamSize(Stream oldStream)
{
var reducedStream = //doSomething(oldStream);
return reducedStream;
}
How can I do this?
Update
I have tried this:
public Stream CompressImage(string imagePath)
{
try
{
// BitmapFactory options to downsize the image
BitmapFactory.Options o = new BitmapFactory.Options();
o.InJustDecodeBounds = true;
o.InSampleSize = 6;
// factor of downsizing the image
FileStream inputStream = new FileStream(imagePath, FileMode.Open);
//Bitmap selectedBitmap = null;
BitmapFactory.DecodeStream(inputStream, null, o);
inputStream.Close();
// The new size we want to scale to
int REQUIRED_SIZE = 75;
// Find the correct scale value. It should be the power of 2.
int scale = 1;
while (o.OutWidth / scale / 2 >= REQUIRED_SIZE &&
o.OutHeight / scale / 2 >= REQUIRED_SIZE)
{
scale *= 2;
}
BitmapFactory.Options o2 = new BitmapFactory.Options();
o2.InSampleSize = scale;
inputStream = new FileStream(imagePath, FileMode.Open);
Bitmap selectedBitmap = BitmapFactory.DecodeStream(inputStream, null, o2);
inputStream.Close();
FileStream outputStream = new FileStream(imagePath, FileMode.Open);
selectedBitmap.Compress(Bitmap.CompressFormat.Jpeg, 100, outputStream);
return outputStream;
}
catch (Exception e)
{
return null;
}
}
But the image is not showing. There must be an error while compressing it.

Related

UWP - scaled image is damaged

I have a problem to place an image with down-scale. Image is rasterized and I don't know find way to place it correctly.
Is it possible to place picture without losing quality ?
Code:
public async Task<BitmapImage> BitmapTransform(string filePath, uint width)
{
StorageFile file = await StorageFile.GetFileFromPathAsync(filePath);
if (file == null)
return null;
// create a stream from the file and decode the image
var fileStream = await file.OpenAsync(Windows.Storage.FileAccessMode.Read);
BitmapDecoder decoder = await BitmapDecoder.CreateAsync(fileStream);
// create a new stream and encoder for the new image
InMemoryRandomAccessStream ras = new InMemoryRandomAccessStream();
BitmapEncoder enc = await BitmapEncoder.CreateForTranscodingAsync(ras, decoder);
double ration =
enc.BitmapTransform.ScaledWidth = width;
enc.BitmapTransform.ScaledHeight = (uint)(((double)decoder.PixelHeight / (double)decoder.PixelWidth) * (double)width);
// write out to the stream
try
{
await enc.FlushAsync();
}
catch (Exception ex)
{
string s = ex.ToString();
}
// render the stream to the screen
BitmapImage bImg = new BitmapImage();
bImg.SetSource(ras);
return bImg;
}
You can choose the way of resizing - Nearest Neighbor, Linear, Cubic, Fant - by BitmapTransform.InterporationMode property.
Have you tried it?
https://msdn.microsoft.com/en-us/library/windows/apps/windows.graphics.imaging.bitmaptransform.interpolationmode
double ration =
enc.BitmapTransform.ScaledWidth = width;
enc.BitmapTransform.ScaledHeight = (uint)(((double)decoder.PixelHeight / (double)decoder.PixelWidth) * (double)width);
enc.BitmapTransform.InterpolationMode = BitmapInterpolationMode.Cubic; // <----- Set the Interporation mode here
But the quality of result is vary. It's depend on the original image.

wma compression audio files throwing error using Naudio

Here I have some codes for encoding wma audio files..Its works perfectly.but uploading out put file to server ,some error happend.Its shows output file should be meet the
requirements like rate should be in 16000
public void ConvertToWMA(string tempFilePath, string tempFileName, string audioType)
{
WaveFormat form = new WaveFormat(16000, 16, 1);
using (WmaStream str = new WmaStream(tempFilePath + tempFileName, form))
{
string profileData;
using (StreamReader reader = new StreamReader(File.OpenRead("audio.prx")))
{
profileData = reader.ReadToEnd();
}
IWMProfileManager profileManager;
IWMProfile wmProfile = null;
profileManager = WM.CreateProfileManager();
profileManager.LoadProfileByData(profileData, out wmProfile);
WMProfile wmp = new WMProfile(str.Profile);
NAudio.WindowsMediaFormat.WmaWriter ww = new NAudio.WindowsMediaFormat.WmaWriter(new FileStream(#"D:\wma\conv\test.wma", FileMode.Create), form, wmProfile);
byte[] buff = null;
int read = 0;
buff = new byte[form.AverageBytesPerSecond];
read = str.Read(buff, 0, buff.Length);
while ((read > 0))
{
ww.Write(buff, 0, read);
read = str.Read(buff, 0, buff.Length);
}
}
}
how can get rid of this issue.someone please help me..
{
var temp = tempFilePath + tempFileName;
using (var reader = new MediaFoundationReader(temp))
{
// Create a wave format for 16-bit pcm at 8000 samples per second.
int channels = reader.WaveFormat.Channels;
int rate = 8000;
int rawsize = 2;
int blockalign = rawsize * channels; // this is the size of one sample.
int bytespersecond = rate * blockalign;
//MediaFoundationEncoder.enc(reader, "test.mp3");
var midformat =
WaveFormat.CreateCustomFormat(WaveFormatEncoding.Pcm,
rate,
channels,
bytespersecond,
blockalign,
rawsize * 8);
// And a conversion stream to turn input into 16-bit PCM.
//var midstream = new MediaFoundationResampler(reader, midformat);
// var outstream = new PcmToALawConversionStream(midstream);
// var outstream = new PcmToALawConversionStream(midstream);
//var converted16Bit = new SampleToWaveProvider16(mixer);
//
// now for MP3, we need to upsample to 44.1kHz. Use MediaFoundationResampler
using (var resampled = new MediaFoundationResampler(
reader, midformat))
{
var outstream = new PcmToALawConversionStream(resampled);
// var desiredBitRate = 16000; // ask for lowest available bitrate
//MediaFoundationEncoder.EncodeToWma(outstream,
// "mixedtets10.wma", desiredBitRate);
WaveFileWriter.CreateWaveFile("mixedtets10.wma", outstream);
//NAudio.WindowsMediaFormat.WmaWriter ww = new NAudio.WindowsMediaFormat.WmaWriter(new FileStream(#"D:\wma\conv\test1.wma", FileMode.Create), midformat, outstream);
}
// NAudio.WindowsMediaFormat.WmaWriter ww = new NAudio.WindowsMediaFormat.WmaWriter(new FileStream(#"D:\wma\conv\test1.wma", FileMode.Create), midformat, outstream);
//NAudio.WindowsMediaFormat.WmaWriter Ww=
// The output stream is our custom stream.
//var outstream = new PcmToALawConversionStream(midstream);
}
}

Images in Windows Phone 8.1 livetiles aren't sharp

I create livetiles with the following code:
// wide 310x150
var tileXml = TileUpdateManager.GetTemplateContent(TileTemplateType.TileWide310x150PeekImage03);
tileXml.GetElementsByTagName(textElementName).LastOrDefault().InnerText = string.Format(artist + " - " + trackname);
var image = tileXml.GetElementsByTagName(imageElementName).FirstOrDefault();
if (image != null)
{
var src = tileXml.CreateAttribute("src");
if (albumart == String.Empty)
src.Value = "Assets/onemusic_logo_wide.scale-240.png";
else
src.Value = albumart;
image.Attributes.SetNamedItem(src);
}
// square 150x150
var squaredTileXml = TileUpdateManager.GetTemplateContent(TileTemplateType.TileSquare150x150PeekImageAndText01);
squaredTileXml.GetElementsByTagName(textElementName).FirstOrDefault().InnerText = string.Format(artist + " - " + trackname);
image = squaredTileXml.GetElementsByTagName(imageElementName).LastOrDefault();
if (image != null)
{
var src = squaredTileXml.CreateAttribute("src");
if (albumart == String.Empty)
src.Value = "Assets/onemusic_logo_square.scale-240.png";
else
src.Value = albumart;
image.Attributes.SetNamedItem(src);
}
updater.Update(new TileNotification(tileXml));
updater.Update(new TileNotification(squaredTileXml));
The problem I face is that the images shown on the livetile aren't sharp (in the app they are). I think this is because of the 310x150 pixels size of the template. I looked at the templates, there aren't any higher resolution ones. Is there a way to make the images sharper?
I noticed that providing an image with a resolution of exactly 744x360 pixels solves the problem. So I wrote this function to resize my albumarts (maybe it will come in handy for someone);
private async static Task<string> CropAndSaveImage(string filePath)
{
const string croppedimage = "cropped_albumart.jpg";
// read file
StorageFile file = await StorageFile.GetFileFromPathAsync(filePath);
if (file == null)
return String.Empty;
// create a stream from the file and decode the image
var fileStream = await file.OpenAsync(Windows.Storage.FileAccessMode.Read);
BitmapDecoder decoder = await BitmapDecoder.CreateAsync(fileStream);
// create a new stream and encoder for the new image
using (InMemoryRandomAccessStream writeStream = new InMemoryRandomAccessStream())
{
// create encoder
BitmapEncoder enc = await BitmapEncoder.CreateForTranscodingAsync(writeStream, decoder);
enc.BitmapTransform.InterpolationMode = BitmapInterpolationMode.Linear;
// convert the entire bitmap to a 744px by 744px bitmap
enc.BitmapTransform.ScaledHeight = 744;
enc.BitmapTransform.ScaledWidth = 744;
enc.BitmapTransform.Bounds = new BitmapBounds()
{
Height = 360,
Width = 744,
X = 0,
Y = 192
};
await enc.FlushAsync();
StorageFile albumartfile = await ApplicationData.Current.LocalFolder.CreateFileAsync(croppedimage, CreationCollisionOption.ReplaceExisting);
using (var stream = await albumartfile.OpenAsync(FileAccessMode.ReadWrite))
{
await RandomAccessStream.CopyAndCloseAsync(writeStream.GetInputStreamAt(0), stream.GetOutputStreamAt(0));
}
// return image path
return albumartfile.Path;
}
}

How to convert a XPS file to an image in high quality (rather than blurry low resolution)?

I'm trying to convert an XPS with WPF.
The idea is that these images can be loaded with silverlight 4, for this I am using the following code:
// XPS Document
XpsDocument xpsDoc = new XpsDocument(xpsFileName, System.IO.FileAccess.Read);
FixedDocumentSequence docSeq = xpsDoc.GetFixedDocumentSequence();
// The number of pages
PageCount = docSeq.References[0].GetDocument(false).Pages.Count;
DocumentPage sizePage = docSeq.DocumentPaginator.GetPage(0);
PageHeight = sizePage.Size.Height;
PageWidth = sizePage.Size.Width;
// Scale dimensions from 96 dpi to 600 dpi.
double scale = 300/ 96;
// Convert a XPS page to a PNG file
for (int pageNum = 0; pageNum < PageCount; pageNum++)
{
DocumentPage docPage = docSeq.DocumentPaginator.GetPage(pageNum);
BitmapImage bitmap = new BitmapImage();
RenderTargetBitmap renderTarget =
new RenderTargetBitmap((int)(scale * (docPage.Size.Height + 1)),
(int)(scale * (docPage.Size.Height + 1)),
scale * 96,
scale * 96, PixelFormats.Pbgra32);
renderTarget.Render(docPage.Visual);
PngBitmapEncoder encoder = new PngBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(renderTarget));
FileStream pageOutStream = new FileStream(name + ".Page" + pageNum + ".png", FileMode.Create, FileAccess.Write);
encoder.Save(pageOutStream);
pageOutStream.Close();
This code is taken from http://xpsreader.codeplex.com/ a project to convert an XPS document.
works great!
But the problem is that the image is low resolution and blurry.
I researched and found that RenderTargetBitmap and find on this page:
http://www.codeproject.com/Questions/213737/Render-target-bitmap-quality-issues
The issue here is you Have That does not use hardware RenderTargetBitmap rendering.
One solution is to use DirectX with WPF to do this, but have not found any clear example to show me the right way to do it.
I appreciate suggestions. Thanks in advance.
Update:I attached the XPS document, I am trying to convert the image
Please download test.xps
There is a project named xps2img on sourceforge.net which converts an xps to image. It is made in C# and also contains the source code. Check it out. It will help you to achieve what you want.
http://sourceforge.net/projects/xps2img/files/
I saw in this post and in many others that peoples have problems with conversion of DocumentPage to Image and saving it on HDD.
This method took all pages from document viewer and save them on HDD as jpg images.
public void SaveDocumentPagesToImages(IDocumentPaginatorSource document, string dirPath)
{
if (string.IsNullOrEmpty(dirPath)) return;
if (dirPath[dirPath.Length - 1] != '\\')
dirPath += "\\";
if (!Directory.Exists(dirPath)) return;
MemoryStream[] streams = null;
try
{
int pageCount = document.DocumentPaginator.PageCount;
DocumentPage[] pages = new DocumentPage[pageCount];
for (int i = 0; i < pageCount; i++)
pages[i] = document.DocumentPaginator.GetPage(i);
streams = new MemoryStream[pages.Count()];
for (int i = 0; i < pages.Count(); i++)
{
DocumentPage source = pages[i];
streams[i] = new MemoryStream();
RenderTargetBitmap renderTarget =
new RenderTargetBitmap((int)source.Size.Width,
(int)source.Size.Height,
96, // WPF (Avalon) units are 96dpi based
96,
System.Windows.Media.PixelFormats.Default);
renderTarget.Render(source.Visual);
JpegBitmapEncoder encoder = new JpegBitmapEncoder(); // Choose type here ie: JpegBitmapEncoder, etc
encoder.QualityLevel = 100;
encoder.Frames.Add(BitmapFrame.Create(renderTarget));
encoder.Save(streams[i]);
FileStream file = new FileStream(dirPath + "Page_" + (i+1) + ".jpg", FileMode.CreateNew);
file.Write(streams[i].GetBuffer(), 0, (int)streams[i].Length);
file.Close();
streams[i].Position = 0;
}
}
catch (Exception e1)
{
throw e1;
}
finally
{
if (streams != null)
{
foreach (MemoryStream stream in streams)
{
stream.Close();
stream.Dispose();
}
}
}
}
A nuget package based on xps2img is now available:
https://www.nuget.org/packages/xps2img/
Api available here:
https://github.com/peters/xps2img#usage
private IList<byte[]> GetTifPagesFromXps(string xXpsFileName, double xQuality)
{
using (var xpsDoc = new XpsDocument(xXpsFileName, FileAccess.Read))
{
var docSeq = xpsDoc.GetFixedDocumentSequence();
var tifPages = new List<byte[]>();
for (var i = 0; i < docSeq.DocumentPaginator.PageCount; i++)
{
using (var docPage = docSeq.DocumentPaginator.GetPage(i))
{
var renderTarget = new RenderTargetBitmap((int)(docPage.Size.Width * xQuality), (int)(docPage.Size.Height * xQuality), 96 * xQuality, 96 * xQuality, PixelFormats.Default);
renderTarget.Render(docPage.Visual);
var jpegEncoder = new JpegBitmapEncoder { QualityLevel = 100 };
jpegEncoder.Frames.Add(BitmapFrame.Create(renderTarget));
byte[] buffer;
using (var memoryStream = new MemoryStream())
{
jpegEncoder.Save(memoryStream);
memoryStream.Seek(0, SeekOrigin.Begin);
buffer = memoryStream.GetBuffer();
}
tifPages.Add(buffer);
}
}
xpsDoc.Close();
return tifPages.ToArray();
}
}

How do you retrieve a snapshot of a website in ASP.NET?

Could anyone tell me how I could retrieve an image or a thumbnail of a website through my ASP.NET application? I have seen this functionality in a few sites such as Alexa etc.
Try SnapCasa's free and easy to use service. Just form your image tag like this:
<img src="http://SnapCasa.com/Get.aspx?code=[code]&size=[size]&url=[url]" />
Requires sign-up, but it's free for 500,000 requests a month. [code] is an api key that they provide after sign-up. [size] is one of three sizes available. [url] is the website address to the site for which you want to display a thumbnail.
If you want to work with the image from your code, here are a couple of helper methods:
static public byte[] GetBytesFromUrl(string url)
{
byte[] b;
HttpWebRequest myReq = (HttpWebRequest)WebRequest.Create(url);
WebResponse myResp = myReq.GetResponse();
Stream stream = myResp.GetResponseStream();
//int i;
using (BinaryReader br = new BinaryReader(stream))
{
//i = (int)(stream.Length);
b = br.ReadBytes(500000);
br.Close();
}
myResp.Close();
return b;
}
static public void WriteBytesToFile(string fileName, byte[] content)
{
FileStream fs = new FileStream(fileName, FileMode.Create);
BinaryWriter w = new BinaryWriter(fs);
try
{
w.Write(content);
}
finally
{
fs.Close();
w.Close();
}
}
Then, in your code, just use:
//get byte array for image
var imageBytes = GetBytesFromUrl("http://SnapCasa.com/Get.aspx?code=[code]&size=[size]&url=[url]");
//save file to disk
WriteBytesToFile("c:\someImageFile.jpg", imageBytes);
Should be doable using a web-browser object and saving the view port to a bitmap resized to thumbnail.
I have not tested this code but try tweaking it after substituting for the thumbnail params.
using (WebBrowser wb = new WebBrowser()) {
wb.ScrollBarsEnabled = false;
wb.AllowNavigation = true;
wb.ScriptErrorsSuppressed = true;
wb.ClientSize = new Size(thumbInfo_viewportWidth, thumbInfo_viewportHeight);
if ((thumbInfo_Uri != null)) {
wb.Navigate(thumbInfo_Uri.AbsoluteUri);
} else {
wb.Navigate("about:blank");
HtmlDocument doc = wb.Document.OpenNew(true);
doc.Write(thumbInfo_HTML);
wb.Refresh(WebBrowserRefreshOption.Completely);
}
// create an image of the client area of the webbrowser control, than
// scale it down to the dimensions specified.
if ((wb.Document != null && wb.Document.Body != null)) {
Rectangle rec = default(Rectangle);
rec.Size = wb.ClientSize;
using (Bitmap fullSizeBitmap = new Bitmap(thumbInfo_viewportWidth, thumbInfo_viewportHeight)) {
wb.DrawToBitmap(fullSizeBitmap, wb.Bounds);
using (Bitmap scaledBitmap = new Bitmap(thumbInfo_width, thumbInfo_height)) {
using (Graphics gr = Graphics.FromImage(scaledBitmap)) {
gr.SmoothingMode = Drawing2D.SmoothingMode.HighQuality;
gr.CompositingQuality = Drawing2D.CompositingQuality.HighQuality;
gr.InterpolationMode = Drawing2D.InterpolationMode.High;
Rectangle rect = new Rectangle(0, 0, thumbInfo_width, thumbInfo_height);
gr.DrawImage(fullSizeBitmap, rect, 0, 0, rec.Size.Width, rec.Size.Height, GraphicsUnit.Pixel);
scaledBitmap.Save(thumbInfo_physicalPath);
}
}
}
}
}
One thing to note that it is an expensive process.

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