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Using SharpAvi to convert images to video

I'm using SharpAvi .dll to convert a serie of images to video, everything looks fine, but when I try to play the video in windows media player I only get a black screen for one second, nothing else.
This is the code I wrote, (frames is a list of images as base64)
private void CreateMovie(List<string> frames)
{
int width = 320;
int height = 240;
var framRate = 2;
var writer = new AviWriter("C:\\test.avi")
{
FramesPerSecond = framRate,
EmitIndex1 = true
};
var stream = writer.AddVideoStream();
stream.Width = width;
stream.Height = height;
stream.Codec = KnownFourCCs.Codecs.DivX;
stream.BitsPerPixel = BitsPerPixel.Bpp32;
foreach (var frame in frames)
{
byte[] arr = Convert.FromBase64String(frame);
stream.WriteFrame(true, arr, 0, arr.Length);
}
writer.Close();
}
I can't see what the error could be. Does anyone have an idea?

So, i've found the errors:
the line:
stream.Codec = KnownFourCCs.Codecs.DivX;
should be:
stream.Codec = KnownFourCCs.Codecs.Uncompressed;
and all the frames of the video should be the same size as video, in order to do that i've use this block of code:
foreach (var frame in frames)
{
byte[] arr = Convert.FromBase64String(frame);
var bm = ToBitmap(arr);
var rbm = ReduceBitmap(bm, 320, 240);
byte[] fr = BitmapToByteArray(rbm);
stream.WriteFrame(true, fr, 0, fr.Length);
}
and here the helper functions:
public Bitmap ToBitmap(byte[] byteArrayIn)
{
var ms = new MemoryStream(byteArrayIn);
var returnImage = Image.FromStream(ms);
var bitmap = new Bitmap(returnImage);
return bitmap;
}
public Bitmap ReduceBitmap(Bitmap original, int reducedWidth, int reducedHeight)
{
var reduced = new Bitmap(reducedWidth, reducedHeight);
using (var dc = Graphics.FromImage(reduced))
{
dc.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
dc.DrawImage(original, new Rectangle(0, 0, reducedWidth, reducedHeight), new Rectangle(0, 0, original.Width, original.Height), GraphicsUnit.Pixel);
}
return reduced;
}
public static byte[] BitmapToByteArray(Bitmap bitmap)
{
BitmapData bmpdata = null;
try
{
bmpdata = bitmap.LockBits(new Rectangle(0, 0, bitmap.Width, bitmap.Height), ImageLockMode.ReadOnly, bitmap.PixelFormat);
int numbytes = bmpdata.Stride * bitmap.Height;
byte[] bytedata = new byte[numbytes];
IntPtr ptr = bmpdata.Scan0;
Marshal.Copy(ptr, bytedata, 0, numbytes);
return bytedata;
}
finally
{
if (bmpdata != null)
{
bitmap.UnlockBits(bmpdata);
}
}
}

SharpAvi Image to ByteArray to Frame to AVI

I'm having some trouble converting an image to a video using the SharpAVI.dll.
I have managed to produce a video file using a randomly generated byte array by using the documentation on SharpAVI's website:
Getting Started with SharpAVI
So the next step I thought I would take was to take an Image, create a Bitmap image, convert the bitmap to a byte array and then simply save the byte array to each frame of the video file. When I run the program, I get no errors or anything and a video file of an appropriate file size is produced however the video file is unreadable and will not open. I'm really struggling to see why this won't work. Any help would be greatly appreciated!
My Code:
private void GenerateSingleImageVideo()
{
string imagePath = textBoxImagePath.Text;
Bitmap thisBitmap;
//generate bitmap from image file
using (Stream BitmapStream = System.IO.File.Open(imagePath, FileMode.Open))
{
Image img = Image.FromStream(BitmapStream);
thisBitmap = new Bitmap(img);
}
//convert the bitmap to a byte array
byte[] byteArray = BitmapToByteArray(thisBitmap);
//creates the writer of the file (to save the video)
var writer = new AviWriter(textBoxFileName.Text + ".avi")
{
FramesPerSecond = int.Parse(textBoxFrameRate.Text),
EmitIndex1 = true
};
var stream = writer.AddVideoStream();
stream.Width = thisBitmap.Width;
stream.Height = thisBitmap.Height;
stream.Codec = KnownFourCCs.Codecs.Uncompressed;
stream.BitsPerPixel = BitsPerPixel.Bpp32;
int numberOfFrames = ((int.Parse(textBoxFrameRate.Text)) * (int.Parse(textBoxVideoLength.Text)));
int count = 0;
while (count <= numberOfFrames)
{
stream.WriteFrame(true, byteArray, 0, byteArray.Length);
count++;
}
writer.Close();
MessageBox.Show("Done");
}
private byte[] BitmapToByteArray(Bitmap img)
{
ImageConverter converter = new ImageConverter();
return (byte[])converter.ConvertTo(img, typeof(byte[]));
}

You're wrong in assuming that you should pass a Bitmap object to WriteFrame method. It expects pixel data in bottom to top 32bpp format. See example in
// Buffer for pixel data
var buffer = new byte[width * height * 4];
...
// Copy pixels from Bitmap assuming it has expected 32bpp pixel format
var bits = bitmap.LockBits(new Rectangle(0, 0, width, height), ImageLockMode.ReadOnly, PixelFormat.Format32bppRgb);
Marshal.Copy(bits.Scan0, buffer, 0, buffer.Length);
bitmap.UnlockBits(bits);
You can see code of a sample app as a reference
https://github.com/baSSiLL/SharpAvi/blob/master/Sample/Recorder.cs

Bitmap Image from Hex string - extra bytes being added

I have a Hex string that's coming from postscript file.
<< /ImageType 1
/Width 986 /Height 1
/BitsPerComponent 8
/Decode [0 1 0 1 0 1]
/ImageMatrix [986 0 0 -1 0 1]
/DataSource <
803fe0503824160d0784426150b864361d0f8844625138a4562d178c466351b8e4763d1f904864523924964d27944a6552b964b65d2f984c665339a4d66d379c4e6753b9e4f67d3fa05068543a25168d47a4526954ba648202
> /LZWDecode filter >> image } def
Below are the methods that I am using. I have commented out the method for updating color.
public static void ProcessImageColourMapping()
{
string imageDataSource = "803fe0503824160d0784426150b864361d0f8844625138a4562d178c466351b8e4763d1f904864523924964d27944a6552b964b65d2f984c665339a4d66d379c4e6753b9e4f67d3fa05068543a25168d47a4526954ba648202";
string imageDataSourceUpdated = GetUpdatedImage(imageDataSource);
}
public static string GetUpdatedImage(string strImageDataSource)
{
string imageDataSourceUpdated = "";
byte[] imageBytes = StringToByteArray(strImageDataSource);
Bitmap bitmapImage = ByteArrayToBitmap(imageBytes);
//UpdateColour(bitmapImage);
byte[] imageBytesUpdated = BitmapToByteArray(bitmapImage);
imageDataSourceUpdated = ByteArrayToString(imageBytesUpdated);
return imageDataSourceUpdated;
}
public static byte[] StringToByteArray(String imageHexString)
{
int numberOfChars = imageHexString.Length / 2;
byte[] byteArray = new byte[numberOfChars];
using (var sr = new StringReader(imageHexString))
{
for (int i = 0; i < numberOfChars; i++)
byteArray[i] = Convert.ToByte(new string(new char[2] { (char)sr.Read(), (char)sr.Read() }), 16);
}
return byteArray;
}
public static Bitmap ByteArrayToBitmap(byte[] byteArray)
{
int width = 986; //width and height are taken from postscript file for testing a single hex string.
int height = 1;
Bitmap bitmapImage = new Bitmap(width, height, PixelFormat.Format32bppPArgb);
BitmapData bmpData = bitmapImage.LockBits(new Rectangle(0, 0, width, height), ImageLockMode.ReadWrite, PixelFormat.Format32bppPArgb);
try
{
Marshal.Copy(byteArray, 0, bmpData.Scan0, byteArray.Length);
}
finally
{
bitmapImage.UnlockBits(bmpData);
}
return bitmapImage;
}
public static byte[] BitmapToByteArray(Bitmap bitmap)
{
BitmapData bmpdata = bitmap.LockBits(new Rectangle(0, 0, bitmap.Width, bitmap.Height), ImageLockMode.ReadOnly, bitmap.PixelFormat);
int numbytes = bmpdata.Stride * bitmap.Height;
byte[] bytedata = new byte[numbytes];
try
{
Marshal.Copy(bmpdata.Scan0, bytedata, 0, numbytes);
}
finally
{
bitmap.UnlockBits(bmpdata);
}
return bytedata;
}
public static string ByteArrayToString(byte[] byteArray)
{
StringBuilder hex = new StringBuilder(byteArray.Length * 2);
foreach (byte b in byteArray)
{
hex.AppendFormat("{0:x2}", b);
}
return hex.ToString();
}
Issue:
In below code, I am not updating anything for incoming Hex string imageDataSource.
Converting it to byte[] - then to Bitmap - Back to byte[] - and finally back to Hex string.
So, imageDataSourceUpdated should have same value as imageDataSource.
However, when I finally check the value for imageDataSourceUpdated, it comes out as:
803fe0503824160d0784426150b864361d0f8844625138a4562d178c466351b8e4763d1f904864523924964d27944a6552b964b65d2f984c665339a4d66d379c4e6753b9e4f67d3fa05068543a25168d47a4526954ba64820200000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000.....
So many zeros being appended.
Can please guide what I am missing here.

You are passing some input string, but the width of the image (and so 1/4 of the size of the byte array) is set to 986 in your sample, which would yield the behaviour you observe - you're not actually passing 986 * 4 bytes of data, but the Bitmap does have that many. So you'll get the first X bytes you actually copied to the bitmap, and then all zeros. In other words, it seems your issue is with your sample data, not with the methods themselves - those work just fine.

C# Problems With Sending/Receiving Size of bytes (Sockets)

I've made these codes to send and receive an Image with a TCP socket but the receive code didn't work.
This is the send code:
public void SendImage()
{
int ScreenWidth = Screen.GetBounds(new Point(0, 0)).Width;
int ScreenHeight = Screen.GetBounds(new Point(0, 0)).Height;
Bitmap bmpScreenShot = new Bitmap(ScreenWidth, ScreenHeight);
Graphics gfx = Graphics.FromImage((Image)bmpScreenShot);
gfx.CopyFromScreen(0, 0, 0, 0, new Size(ScreenWidth, ScreenHeight));
bmpScreenShot.Save(Application.StartupPath + "/ScreenShot.jpg", ImageFormat.Jpeg);
byte[] image = new byte[1];
bmpScreenShot = ResizeBitmap(bmpScreenShot, 300, 300);
image = ImageToByte(bmpScreenShot);
//get the length of image (length of bytes)
int NumberOfBytes = image.Length;
//put the size into a byte array
byte[] numberofbytesArray = BitConverter.GetBytes(NumberOfBytes);
//send the size to the Client
int sizesend = sck.Send(numberofbytesArray, 0, numberofbytesArray.Length, 0);
if (sizesend > 0)
{
MessageBox.Show("Size Sent");
}
//send the image to the Client
int imagesend =sck.Send(image, 0, NumberOfBytes, 0);
if (imagesend > 0)
{
MessageBox.Show("Image Sent");
}
}
And here is the receive code:
public void ReceiveImage()
{
if (sck.Connected)
{
{
NetworkStream stream = new NetworkStream(sck);
byte[] data = new byte[4];
//Read The Size
stream.Read(data, 0, data.Length);
int size = (BitConverter.ToInt32(data,0));
// prepare buffer
data = new byte[size];
//Load Image
int read = 0;
while (read != data.Length)
{
read += stream.Read(data, read, data.Length - read);
}
//stream.Read(data, 0, data.Length);
//Convert Image Data To Image
MemoryStream imagestream = new MemoryStream(data);
Bitmap bmp = new Bitmap(imagestream);
pictureBox1.Image = bmp;
}
}
}
The problem is when i send the size, its sent as 5kb but when i receive it i find it 2GB and this error comes up:
Unable to read data from the transport connection. An operation on a socket could be performed because the system lacked sufficient buffer space or because a queue was full.
The error is at this statement read += stream.Read(data, read, data.Length - read);

I would try getting smaller chunks of data. In your code you're starting off with all the data (2GB at a time in the case that fails. Drop that down to something smaller--the data is sent in chunks anyway. For example:
read += stream.Read(buffer, read, 20480);
this will read about 2k at a time so as to not be larger than the buffer space or be too large for the queue.
If you've allocated a buffer of 2GB in size, your application likely has very little memory left. The underlying framework is probably unable to allocated 2GB of data for itself (4GB total allocated) to transfer data.

Byte Array to Bitmap Image

I made this code to receive an image and convert it to bitmap image but it doesn't work.
Here is the code:
public void ReceiveImage()
{
NetworkStream stream = new NetworkStream(socket);
byte[] data = new byte[4];
stream.read(data,0,data.length,0)
int size = BitConverter.ToInt32(data,0);
data = new byte[size];
stream.read(data,0,data.length)
MemoryStream imagestream = new MemoryStream(data);
Bitmap bmp = new Bitmap(imagestream);
picturebox1.Image = bmp;
}
It gets to:
Bitmap bmp = new Bitmap(imagestream);
And gives me this error:
Parameter is not valid

This is an alternative method
int w= 100;
int h = 200;
int ch = 3; //number of channels (ie. assuming 24 bit RGB in this case)
byte[] imageData = new byte[w*h*ch]; //you image data here
Bitmap bitmap = new Bitmap(w,h,PixelFormat.Format24bppRgb);
BitmapData bmData = bitmap.LockBits(new System.Drawing.Rectangle(0, 0, bitmap.Width, bitmap.Height), ImageLockMode.ReadWrite, bitmap.PixelFormat);
IntPtr pNative = bmData.Scan0;
Marshal.Copy(imageData,0,pNative,w*h*ch);
bitmap.UnlockBits(bmData);

You are probably not receiving enough bytes in stream.read(data,0,data.length) since Read does not ensure that it will read data.length bytes. you have to check its return value and continue to read till data.Length bytes are read.
See : Stream.Read Method's return value
int read = 0;
while (read != data.Length)
{
read += stream.Read(data, read, data.Length - read);
}
PS: I am assuming lengths and reads are typos.

I assume you have a table and want to receive the picture from database.
int cout = ds.Tables["TableName"].Rows.Count;
if (cout > 0)
{
if (ds.Tables["TableName"].Rows[cout - 1]["Image"] != DBNull.Value)
{
var data = (byte[])(ds.Tables["TableName"].Rows[cout - 1]["Image"]);
var stream = new MemoryStream(data);
pictureBox1.Image = Image.FromStream(stream);
}
else
{
pictureBox1.Image = null;
}
}

Try this:
int size = BitConverter.ToInt32(data.Reverse().ToArray(),0);