I have a simple C# script that generates a Bitmap, saves it to the hard drive (PNG), checks the file Size and based on the size of the file it will move or delete the image.
Bitmap bmp = new Bitmap(1024, 768);
bmp.save(#"C:\User\...\image.png");
FileInfo fi = new FileInfo (#"C:\User\...\image.png");
if (fi.length > 50000){
//do Something
}
Is there any other way to get the compressed (RLE) size of the Bitmap without storing it locally?
You can save the image to a MemoryStream instead:
Bitmap bmp = new Bitmap(1024, 768);
using (var ms = new MemoryStream())
{
bmp.Save(ms, ImageFormat.Png);
if (ms.Length > 50000){
//do Something
}
}
Related
//Retrieve an image in Jpg format and store it into a variable.
var imgFile = (ImageFile)ScanerItem.Transfer(FormatID.wiaFormatJPEG);
var Path = #"D:\ScanImg.jpg";
// save the image in some path with filename.
imgFile.SaveFile(Path);
pictureBox1.ImageLocation = Path;
Based on the following SO answer, you can get the byte[] of the image with (byte[])imgFile.FileData.get_BinaryData():
converting .__comobj WIA to byte[] in C# application
A bitmap can be put as source into the PictureBox.
Therefore the byte[] as to put into a MemoryStream and create a Bitmap:
var imgFile = (ImageFile)ScanerItem.Transfer(FormatID.wiaFormatJPEG);
byte[] imageBytes = (byte[])imgFile.FileData.get_BinaryData();
Bitmap image;
using (MemoryStream stream = new MemoryStream(imageBytes))
{
image = new Bitmap(stream);
}
pictureBox1.Image = image;
I have an operation on the site that takes crops an image, however the resultant, cropped image is coming out significantly larger in terms of file size (original is 24k and the cropped image is like 650k). So I found that I need to apply some compression to the image before saving it. I came up with the following:
public static System.Drawing.Image CropImage(System.Drawing.Image image, Rectangle cropRectangle, ImageFormat format)
{
var croppedImage = new Bitmap(cropRectangle.Width, cropRectangle.Height);
using (var g = Graphics.FromImage(croppedImage))
{
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
g.DrawImage(
image,
new Rectangle(new Point(0,0), new Size(cropRectangle.Width, cropRectangle.Height)),
cropRectangle,
GraphicsUnit.Pixel);
return CompressImage(croppedImage, format);
}
}
public static System.Drawing.Image CompressImage(System.Drawing.Image image, ImageFormat imageFormat)
{
var bmp = new Bitmap(image);
var codecInfo = EncoderFactory.GetEncoderInfo(imageFormat);
var encoder = System.Drawing.Imaging.Encoder.Quality;
var parameters = new EncoderParameters(1);
var parameter = new EncoderParameter(encoder, 10L);
parameters.Param[0] = parameter;
using (var ms = new MemoryStream())
{
bmp.Save(ms, codecInfo, parameters);
var resultImage = System.Drawing.Image.FromStream(ms);
return resultImage;
}
}
I set the quality low just to see if there was any change at all. There isn't. The crop is being saved correctly appearance-wise but compression is a no joy. If I bypass CompressImage() altogether, neither the file size nor the image quality appear to be any different.
So, 2 questions. Why is nothing happening? Is there a simpler way to compress the resultant image to "web-optimize" similar to how photoshop saves web images (I thought it just stripped a lot of info out of it to reduce the size).
Your problem is you must 'compress' (really encode) the image as you save it, not before you save it. An Image object in your program is always uncompressed.
By saving to the MemoryStream and reading back out from the stream will encode the image and then decode it back to the same size again (with some quality loss in the process if you are using JPEG). However, if you save it to a file with the compression parameters, you will get a compressed image file.
Using this routine with JPEG quality level 90 on a 153 KB source image gives an output image of 102 KB. If you want a smaller file size (with more encoding artifacts) change the encoder parameter to something smaller than 90.
public static void SaveJpegImage(System.Drawing.Image image, string fileName)
{
ImageCodecInfo codecInfo = ImageCodecInfo.GetImageEncoders()
.Where(r => r.CodecName.ToUpperInvariant().Contains("JPEG"))
.Select(r => r).FirstOrDefault();
var encoder = System.Drawing.Imaging.Encoder.Quality;
var parameters = new EncoderParameters(1);
var parameter = new EncoderParameter(encoder, 90L);
parameters.Param[0] = parameter;
using (FileStream fs = new FileStream(fileName, FileMode.Create))
{
image.Save(fs, codecInfo, parameters);
}
}
I believe you shouldn't dispose of the MemoryStream while you are using an image created using Image.FromStream that refers to the stream. Creating a Bitmap directly from the stream also doesn't work.
Try this:
private static Image CropAndCompressImage(Image image, Rectangle rectangle, ImageFormat imageFormat)
{
using(Bitmap bitmap = new Bitmap(image))
{
using(Bitmap cropped = bitmap.Clone(rectangle, bitmap.PixelFormat))
{
using (MemoryStream memoryStream = new MemoryStream())
{
cropped.Save(memoryStream, imageFormat);
return new Bitmap(Image.FromStream(memoryStream));
}
}
}
}
Hi I wanna convert binary array to bitmap and show image in a picturebox. I wrote the following code but I got exception that says that the parameter is not valid .
public static Bitmap ByteToImage(byte[] blob)
{
MemoryStream mStream = new MemoryStream();
byte[] pData = blob;
mStream.Write(pData, 0, Convert.ToInt32(pData.Length));
Bitmap bm = new Bitmap(mStream);
mStream.Dispose();
return bm;
}
It really depends on what is in blob. Is it a valid bitmap format (like PNG, BMP, GIF, etc?). If it is raw byte information about the pixels in the bitmap, you can not do it like that.
It may help to rewind the stream to the beginning using mStream.Seek(0, SeekOrigin.Begin) before the line Bitmap bm = new Bitmap(mStream);.
public static Bitmap ByteToImage(byte[] blob)
{
using (MemoryStream mStream = new MemoryStream())
{
mStream.Write(blob, 0, blob.Length);
mStream.Seek(0, SeekOrigin.Begin);
Bitmap bm = new Bitmap(mStream);
return bm;
}
}
Don't dispose of the MemoryStream. It now belongs to the image object and will be disposed when you dispose the image.
Also consider doing it like this
var ms = new MemoryStream(blob);
var img = Image.FromStream(ms);
.....
img.Dispose(); //once you are done with the image.
System.IO.MemoryStream mStrm = new System.IO.MemoryStream(your byte array);
Image im = Image.FromStream(mStrm);
im.Save("image.bmp");
Try this. If you still get any error or exception; please post your bytes which you are trying to convert to image. There should be problem in your image stream....
My ASP.NET application has an image cropping and resizing features. This requires that the uploaded temporary image be deleted. Everything works fine, but when I try to delete an image larger than 80px by 80px I get a "File is locked by another process..." error, even though I've released all resources.
Here's a snippet:
System.Drawing.Image tempimg = System.Drawing.Image.FromFile(temppath);
System.Drawing.Image img = (System.Drawing.Image) tempimg.Clone(); //advice from another forum
tempimg.Dispose();
img = resizeImage(img, 200, 200); //delete only works if it's 80, 80
img.Save(newpath);
img.Dispose();
File.Delete(temppath);
I think you are not disposing the first Image instance assigned to the img variable.
Consider this instead:
System.Drawing.Image tempimg = System.Drawing.Image.FromFile(temppath);
System.Drawing.Image img = (System.Drawing.Image) tempimg.Clone();
tempimg.Dispose();
System.Drawing.Image img2 = resizeImage(img, 200, 200);
img2.Save(newpath);
img2.Dispose();
img.Dispose();
File.Delete(temppath);
If you create the image this way, it won't be locked:
using (FileStream fs = new FileStream(info.FullName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
{
byte[] data = new byte[fs.Length];
int read = fs.Read(data, 0, (int)fs.Length);
MemoryStream ms = new MemoryStream(data, false);
return Image.FromStream(ms, false, false); // prevent GDI from holding image file open
}
I'm doing this paint application. It's kind of simple. It consist of a panel where I will draw on and then finally I will save as JPG or BMP or PNG file.
My application work perfectly but the problem I'm facing is that when I'm saving the output is not what drawn on the panel its black Image nothing just black.
all my work is been saved as
Thepic = new Bitmap(panel1.ClientRectangle.Width, this.ClientRectangle.Height);
and on the mouse (down,up thing) I have
snapshot = (Bitmap)tempDraw.Clone();
and it saved the work normally but again the rsult is black Image not what the panel contain.
I think the problem may be that you're using the "Clone" method.
Try "DrawToBitmap" - that's worked for me in the past.
Here's a sample that saves a bitmap from a control called "plotPrinter":
int width = plotPrinter.Size.Width;
int height = plotPrinter.Size.Height;
Bitmap bm = new Bitmap(width, height);
plotPrinter.DrawToBitmap(bm, new Rectangle(0, 0, width, height));
bm.Save(#"D:\TestDrawToBitmap.bmp", ImageFormat.Bmp);
Be aware of saving directly to the C directly as this is not
permitted with newer versions of window, try using SaveFileDialog.
SaveFileDialog sf = new SaveFileDialog();
sf.Filter = "Bitmap Image (.bmp)|*.bmp|Gif Image (.gif)|*.gif|JPEG Image (.jpeg)|*.jpeg|Png Image (.png)|*.png|Tiff Image (.tiff)|*.tiff|Wmf Image (.wmf)|*.wmf";
sf.ShowDialog();
var path = sf.FileName;
You could try this, this works for me.
I used MemoryStream.
MemoryStream ms = new MemoryStream();
Bitmap bmp = new Bitmap(panel1.Width, panel1.Height);
panel1.DrawToBitmap(bmp, new System.Drawing.Rectangle(0, 0, panel1.Width, panel1.Height));
bmp.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg); //you could ave in BPM, PNG etc format.
byte[] Pic_arr = new byte[ms.Length];
ms.Position = 0;
ms.Read(Pic_arr, 0, Pic_arr.Length);
ms.Close();