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How to show a specific frame of a GIF image in C#?

I want to show a frame of a gif image. I searched and found that the following code should work, but it doesn't work. it detects the number of frames correctly but it shows the whole frames of gif instead of the specified frame. thanks everybody.
Image[] frames = new Image[36];
Image GG = Image.FromFile(#"C:\Users\Administrator\TEST C#\TEST2frame2\chef.gif");
FrameDimension dimension = new FrameDimension(GG.FrameDimensionsList[0]);
// Number of frames
int frameCount = GG.GetFrameCount(dimension);
label1.Text = frameCount.ToString();
// Return an Image at a certain index
GG.SelectActiveFrame(dimension, 1);
frames[1] = ((Image)GG.Clone());
pictureBox1.Image = frames[1];

Use your own code up until the call of SelectActiveFrame() and after that change to this lines:
frames[0] = new Bitmap(GG);
pictureBox1.Image = frame[0];
This should do the trick. Please do not forget do dispose the created Images.

Oh it works, but not as you expect it to.
When you set an active frame of a gif image it actually restarts its animation from that frame. You have to stop it when you change a frame, by setting the pictureBox.IsEnabled to false, for instance. Try the following code
private Image img;
public Form1()
{
InitializeComponent();
img = Image.FromFile(#"C:\Users\Administrator\TEST C#\TEST2frame2\chef.gif");
pictureBox1.Image = img;
}
private void button1_Click(object sender, EventArgs e)
{
var dim = new FrameDimension(img.FrameDimensionsList[0]);
img.SelectActiveFrame(dim, 1);
pictureBox1.Enabled = false;
}
Try pressing the button in different moments and you will see that the active image frame will change.

Why do I keep getting a 'System.OutOfMemoryException'?

Here is my Code, I am trying to stitch two pictures together and as soon as I get to line 42 "Image img = Image.FromFile(file.FullName);" I get an out of memory error. What should I do?
namespace Practicing_Stiching
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void cmdCombine_Click(object sender, EventArgs e)
{
//Change the path to location where your images are stored.
DirectoryInfo directory = new DirectoryInfo(#"C:\Users\Elder Zollinger\Desktop\Images");
if (directory != null)
{
FileInfo[] files = directory.GetFiles();
CombineImages(files);
}
}
private void CombineImages(FileInfo[] files)
{
//change the location to store the final image.
string finalImage = #"C:\Users\Elder Zollinger\Desktop\Images";
List<int> imageHeights = new List<int>();
int nIndex = 0;
int width = 0;
foreach (FileInfo file in files)
{
Image img = Image.FromFile(file.FullName);
imageHeights.Add(img.Height);
width += img.Width;
img.Dispose();
}
imageHeights.Sort();
int height = imageHeights[imageHeights.Count - 1];
Bitmap img3 = new Bitmap(width, height);
Graphics g = Graphics.FromImage(img3);
g.Clear(SystemColors.AppWorkspace);
foreach (FileInfo file in files)
{
Image img = Image.FromFile(file.FullName);
if (nIndex == 0)
{
g.DrawImage(img, new Point(0, 0));
nIndex++;
width = img.Width;
}
else
{
g.DrawImage(img, new Point(width, 0));
width += img.Width;
}
img.Dispose();
}
g.Dispose();
img3.Save(finalImage, System.Drawing.Imaging.ImageFormat.Jpeg);
img3.Dispose();
imageLocation.Image = Image.FromFile(finalImage);
}
}
}

That's likely GDI playing tricks on you.
You see, when GDI encounters an unknown file, it will quite likely cause an OutOfMemoryException. Since you're not filtering the input images at all, I'd expect that you're simply grabbing a non-image file (or an image type that GDI doesn't understand).
Oh, and a bit sideways - make sure you set JPEG quality when saving JPEGs - the default is something like 75, which is rather bad for a lot of images. And please, do use using - it's very handy to ensure proper and timely clean-up :)

Get more memory!
But seriously, you don't appear to be filtering out files that are not image files. There are some hidden files in folders that you may be trying to open as an image accidentally, such as "Thumbs.db". Make sure that the file is an image with something like if (Path.GetExtension(file.FullPath) != ".png") continue;.
Also, on objects that you are calling .Dispose() on, consider wrapping them in a using() instead. For example:
using(var img = Image.FromFile(file.FullPath))
{
// ...
}

How to Reduce Size of Image in windows phone

I am trying to port my app in windows phone . i have to upload an image on server So it is in small Size For uploading i have done this thing in Widows Successfully but problem is when i failed in it .. here is my code for windows App
public void CompressImage(int i, int j)
{
bmp1.SetPixel(j, i, Color.FromArgb(bmp.GetPixel(j, i).R, bmp.GetPixel(j, i).G, bmp.GetPixel(j, i).B));
}
private void bLoadImage_Click(object sender, EventArgs e)
{
OpenFileDialog file = new OpenFileDialog();
if (file.ShowDialog() == DialogResult.OK)
{
pictureBox1.Image = new Bitmap(file.FileName);
}
}
private void bCompression_Click(object sender, EventArgs e)
{
bmp = new Bitmap(pictureBox1.Image);
bmp1 = new Bitmap(bmp.Width, bmp.Height);
for (int i = 1; i < bmp.Height; i++)
for (int j = 1; j < bmp.Width; j++)
{
CompressImage(i, j);
}
pictureBox2.Image = bmp1;
bmp1.Save("Picture.jpeg", System.Drawing.Imaging.ImageFormat.Jpeg);
}
After Searching on google i found out that windows Phone does not support Bitmap .. any idea how i can do the same thing in windows phone or any other alternative for doing this

You should use WriteablBitmap to reduce size of image. WriteablBitmap has number of methods for images in windows phone Here is more about writeablebitmapex.

Try to load your original image to WriteableBitmap object, then you can use SaveJpeg() extension method from System.Windows.Media.Imaging namespace, to save new image with reduced size. For example :
.......
WriteableBitmap wb = new WriteableBitmap(bitmapImageObject);
wb.SaveJpeg(stream, 120, 160, 0, 100);
.......

When you are taking picture you can choose the resolution with which the picture will be taken. This can be done by
PhotoCamera cam;
After camera initizalition.
Following code when image is capturing (in the method that captures the image)
IEnumerable<Size> resList = cam.AvailableResolutions;
Size res;
if (resList.Count() > 0)
{
res = resList.ElementAt<Size>(0);
cam.Resolution = res;
}
This sample chooses the first resolution

You can try this. It worked for me. It reduced my 9.70MB file into 270KB.
WriteableBitmap cameraCapturedImage = PictureDecoder.DecodeJpeg(e.ChosenPhoto, 1024, 1024);
using (IsolatedStorageFileStream myFileStream = myStore.CreateFile(fileName))
{
System.Windows.Media.Imaging.Extensions.SaveJpeg(cameraCapturedImage, myFileStream, cameraCapturedImage.PixelWidth, cameraCapturedImage.PixelHeight, 0, 85);
myFileStream.Close();
}
N.B: fileName is the name of file to save size reduced image.

Printing PDF using GhostScript.NET DPI printing issue

I am using GhostScript.NET to print a PDF.
When I print it at 96DPI, the PDF prints fine, but is a little blurry.
If I try to print the document at 600DPI, the page that prints extremely magnified.
using GhostScript.NET.Rasterizer;
using System.Drawing.Printing;
PrintDocument doc = new PrintDocument();
doc.PrinterSettings.PrinterName="<printer name>";
doc.PrinterSettings.Copies=(short)1;
GhostScriptRasterizer rasterizer = new GhostScriptRasterizer();
rasterizer.Open("abc.pdf");
//Image page = rasterizer.GetPage(96,96); <-- this one prints ok
Image page = rasterizer.GetPage(600,600);
doc.Graphics.DrawImage(page, new Point());
One thing that I noticed when looking at the page object was that although I passed GetPage() 600, 600 - the image returned had a HorizontalResolution of 96 and a VerticalResolution of 96.
So I tried the following:
Bitmap b = new Bitmap(page.Width,page.Height);
b.SetResolution(600,600);
Graphics g = Graphics.FromImage(b);
g.DrawImage(page,0,0);
page = b;
This has a HorizontalResolution of 600 and VerticalResolution of 600, but this printed the image even larger!
Can anyone give advice here?

hi i got the same Problem.
The Rasterizer only zoom to the dpi...
you have to use the GhostScriptProcessor.
private List<string> GetImageWithGhostGhostscriptProcessor(string psFilename, string outputPath, int dip = 300)
{
if (!Directory.Exists(outputPath))
Directory.CreateDirectory(outputPath);
GhostscriptVersionInfo gv = GhostscriptVersionInfo.GetLastInstalledVersion(
GhostscriptLicense.GPL | GhostscriptLicense.AFPL,
GhostscriptLicense.GPL);
using (GhostscriptProcessor processor = new GhostscriptProcessor(gv, true))
{
processor.Processing += new GhostscriptProcessorProcessingEventHandler(processor_Processing);
List<string> switches = new List<string>();
switches.Add("-empty");
switches.Add("-dSAFER");
switches.Add("-dBATCH");
switches.Add("-dNOPAUSE");
switches.Add("-dNOPROMPT");
switches.Add(#"-sFONTPATH=" + System.Environment.GetFolderPath(System.Environment.SpecialFolder.Fonts));
switches.Add("-dFirstPage=" + 1);
switches.Add("-dLastPage=" + 1);
//switches.Add("-sDEVICE=png16m");
switches.Add("-sDEVICE=tiff24nc");
//switches.Add("-sDEVICE=pdfwrite");
switches.Add("-r" + dip);
switches.Add("-dTextAlphaBits=4");
switches.Add("-dGraphicsAlphaBits=4");
switches.Add(#"-sOutputFile=" + outputPath + "\\page-%03d.tif");
//switches.Add(#"-sOutputFile=" + outputPath + "page-%03d.png");
switches.Add(#"-f");
switches.Add(psFilename);
processor.StartProcessing(switches.ToArray(), null);
}
return Directory.EnumerateFiles(outputPath).ToList();
}

I think that the parameters that you are passing into the DrawImage method should be the size you want the image on the paper rather than leaving them by default, the DrawImage command will then take care of the scaling for you. Probably the easiest way is to use the following override of the DrawImage command.
Note: This will skew the image if the proportions of the image are not the same as the rectangle. Some simple math on the size of the image and paper size will allow you to create a new rectangle that fits in the bounds of the paper without skewing the image.
This is what works for me:
int desired_x_dpi = 600;
int desired_y_dpi = 600;
Image img = rasterizer.GetPage(desired_x_dpi, desired_y_dpi, pageNumber);
System.Drawing.Printing.PrintDocument pd = new System.Drawing.Printing.PrintDocument();
pd.PrintPage += (sender, args) =>
{
args.Graphics.DrawImage(img, args.MarginBounds);
};
pd.Print();

Tracking Blobs with Microsoft Kinect

I am working on a people counter. For this I have the Microsoft Kinect installed over the door.
I am working with C# and EmguCV. I have extracted the heads of the people, so that they appear as white blobs on a black image. Then I have created a bounding box around the heads. That works fine. So I now how many blobs I have per frame and I also now their position. This works fine. But now I want to track the blobs because I want to count how much people come in and go out, but I don't know how to do this. Can anyone help me? The problem is that every frame, new blobs can appear and old blobs can disappear. Can anyone give me an algorithm or maybe some code? or a paper.
Thanks a lot!
Sure. This is the code for the blobs:
using (MemStorage stor = new MemStorage())
{
Contour<System.Drawing.Point> contours = head_image.FindContours(Emgu.CV.CvEnum.CHAIN_APPROX_METHOD.CV_CHAIN_APPROX_SIMPLE, Emgu.CV.CvEnum.RETR_TYPE.CV_RETR_EXTERNAL, stor);
for (int i = 0; contours != null; contours = contours.HNext)
{
i++;
//if ((contours.Area > Math.Pow(sliderMinSize.Value, 2)) && (contours.Area < Math.Pow(sliderMaxSize.Value, 2)))
{
MCvBox2D box = contours.GetMinAreaRect();
blobCount++;
contour_image.Draw(box, new Bgr(System.Drawing.Color.Red), 1);
new_position = new System.Drawing.Point((int)(box.center.X), (int)(box.center.Y));
new_x = box.center.X;
new_y = box.center.Y;
}
}
}

Please see Emgu CV Blob Detection for more information. Assuming you are using Emgu CV 2.1 or higher, then the answer will work. If you are using version 1.5 or higher, see this thread on how to easily detect blobs. Or look at the code below
Capture capture = new Capture();
ImageViewer viewer = new ImageViewer();
BlobTrackerAutoParam param = new BlobTrackerAutoParam();
param.ForgroundDetector = new ForgroundDetector(Emgu.CV.CvEnum.FORGROUND_DETECTOR_TYPE.FGD);
param.FGTrainFrames = 10;
BlobTrackerAuto tracker = new BlobTrackerAuto(param);
Application.Idle += new EventHandler(delegate(object sender, EventArgs e)
{
tracker.Process(capture.QuerySmallFrame().PyrUp());
Image<Gray, Byte> img = tracker.GetForgroundMask();
//viewer.Image = tracker.GetForgroundMask();
MCvFont font = new MCvFont(Emgu.CV.CvEnum.FONT.CV_FONT_HERSHEY_SIMPLEX, 1.0, 1.0);
foreach (MCvBlob blob in tracker)
{
img.Draw(Rectangle.Round(blob), new Gray(255.0), 2);
img.Draw(blob.ID.ToString(), ref font, Point.Round(blob.Center), new Gray(255.0));
}
viewer.Image = img;
});
viewer.ShowDialog();
Hope this helps!
EDIT
I think you should use this code every ten frames or so (~3 times a second) and do something like this:
Capture capture = new Capture();
ImageViewer viewer = new ImageViewer();
BlobTrackerAutoParam param = new BlobTrackerAutoParam();
param.ForgroundDetector = new ForgroundDetector(Emgu.CV.CvEnum.FORGROUND_DETECTOR_TYPE.FGD);
param.FGTrainFrames = 10;
BlobTrackerAuto tracker = new BlobTrackerAuto(param);
int frames = 0;
Application.Idle += new EventHandler(delegate(object sender, EventArgs e)
{
frames++;//Add to number of frames
if (frames == 10)
{
frames = 0;//if it is after 10 frames, do processing and reset frames to 0
tracker.Process(capture.QuerySmallFrame().PyrUp());
Image<Gray, Byte> img = tracker.GetForgroundMask();
//viewer.Image = tracker.GetForgroundMask();
int blobs = 0;
MCvFont font = new MCvFont(Emgu.CV.CvEnum.FONT.CV_FONT_HERSHEY_SIMPLEX, 1.0, 1.0);
foreach (MCvBlob blob in tracker)
{
//img.Draw(Rectangle.Round(blob), new Gray(255.0), 2);
//img.Draw(blob.ID.ToString(), ref font, Point.Round(blob.Center), new Gray(255.0));
//Only uncomment these if you want to draw a rectangle around the blob and add text
blobs++;//count each blob
}
blobs = /*your counter here*/;
blobs = 0; //reset
viewer.Image = img;//get next frame
});
viewer.ShowDialog();
EDIT 2
It sounds like you just want to identify the blobs, it sounds like you want McvBlob.ID. This is the ID of the blob and you can check which ID's are still there and which are not. I would still do this every ten frames to not slow it down as much. You just need a simple algorithm that can observe what the ID's are, and if they have changed. I would store the IDs in a List<string> and check that list for changes every few frames. Example:
List<string> LastFrameIDs, CurrentFrameIDs;
Capture capture = new Capture();
ImageViewer viewer = new ImageViewer();
BlobTrackerAutoParam param = new BlobTrackerAutoParam();
param.ForgroundDetector = new ForgroundDetector(Emgu.CV.CvEnum.FORGROUND_DETECTOR_TYPE.FGD);
param.FGTrainFrames = 10;
BlobTrackerAuto tracker = new BlobTrackerAuto(param);
int frames = 0;
Application.Idle += new EventHandler(delegate(object sender, EventArgs e)
{
frames++;//Add to number of frames
if (frames == 10)
{
frames = 0;//if it is after 10 frames, do processing and reset frames to 0
tracker.Process(capture.QuerySmallFrame().PyrUp());
Image<Gray, Byte> img = tracker.GetForgroundMask();
//viewer.Image = tracker.GetForgroundMask();
int blobs = 0, i = 0;
MCvFont font = new MCvFont(Emgu.CV.CvEnum.FONT.CV_FONT_HERSHEY_SIMPLEX, 1.0, 1.0);
foreach (MCvBlob blob in tracker)
{
i++;
//img.Draw(Rectangle.Round(blob), new Gray(255.0), 2);
//img.Draw(blob.ID.ToString(), ref font, Point.Round(blob.Center), new Gray(255.0));
//Only uncomment these if you want to draw a rectangle around the blob and add text
CurrentFrameIDs.Add(blob.ID.ToString());
if (CurrentFrameIDs[i] == LastFrameIDs[i])
img.Draw(Rectangle.Round(blob), new Gray(0,0), 2);//mark the new/changed blob
blobs++;//count each blob
}
blobs = /*your counter here*/;
blobs = 0; //reset
i = 0;
LastFrameIDs = CurrentFrameIDs;
CurrentFrameIDs = null;
viewer.Image = img;//get next frame
});
viewer.ShowDialog();