I need to create a small, simple TIFF image that is just black text on a white background, as part of a support library we use across several of our products. (Think a simple receipt or deposit ticket, that kind of thing). I would prefer not to have to use any third-party libraries, to avoid requiring us to add additional dependencies to all of the existing products that use the library.
I have almost gotten the problem solved using just WPF, based on the code from this question. The TIFF is created and rendered properly, but the text quality is horrible. As far as I can determine, the problem is that RenderTargetBitmap, at least the way I'm using it, isn't doing any kind of anti-aliasing, isn't using ClearType, or otherwise is just really bad at rendering plain text, e.g.:
I've read similar questions, such as this one or this one, but they all seem to discuss how to capture text from a visual control or window handle without reducing the quality. I'm doing this entirely off-screen, so I'm not clear if/how I can apply those solutions to my problem.
What I'm currently doing is:
var visual = new DrawingVisual();
using (var draw = visual.RenderOpen())
{
// 'background' is a pre-loaded blank white bitmap
draw.DrawImage(background, new Rect(0, 0, IMG_WIDTH, IMG_HEIGHT));
var font = new Typeface("Segoe UI");
Func<string, FormattedText> format = s => new FormattedText(
s,
CultureInfo.CurrentUICulture,
FlowDirection.LeftToRight,
font,
16,
Brushes.Black);
draw.DrawText(format("Some text"), new Point(HEADER_LEFT, HEADER_TOP);
// Call draw.DrawText a whole bunch more times.
.
.
.
}
var render = new RenderTargetBitmap(IMG_WIDTH, IMG_HEIGHT, IMG_DPI, IMG_DPI, PixelFormats.Default);
render.Render(visual);
var encoder = new TiffBitmapEncoder()
{
Compression = TiffCompressOption.Ccitt4
};
encoder.Frames.Add(BitmapFrame.Create(render));
var stream = new MemoryStream();
encoder.Save(stream);
Is there something else I can put in there to get the text quality better than what it is?
Don't use Ccitt4, it's for black-and-white images only. Try Default instead.
UPDATE:
It's a TT font and you're trying to render it at a small size, no matter what you do it's going to look pretty crap. Still, if you insist then don't use a visual. Screen elements use hardware acceleration, when you use them with a render target as you are here it has to fall back to a software approach which isn't always pixel-for-pixel the same. And either way you always get at least some aliasing. If you really do want proper bitonal then you'll have to use a Graphics object which will use GDI:
var bitmap = new Bitmap(512, 256);
var graphics = Graphics.FromImage(bitmap);
graphics.Clear(System.Drawing.Color.White);
var font = new Font("Segoe UI", 16);
graphics.TextRenderingHint = System.Drawing.Text.TextRenderingHint.SingleBitPerPixelGridFit;
graphics.DrawString("Hello World", font, System.Drawing.Brushes.Black, 0, 0);
ImageCodecInfo myImageCodecInfo = GetEncoderInfo("image/tiff");
var myEncoderParameters = new EncoderParameters(1);
myEncoderParameters.Param[0] = new EncoderParameter(System.Drawing.Imaging.Encoder.Compression, (long)EncoderValue.CompressionCCITT4);
bitmap.Save(#"myimage.tif", myImageCodecInfo, myEncoderParameters);
graphics.Dispose();
private static ImageCodecInfo GetEncoderInfo(String mimeType)
{
int j;
ImageCodecInfo[] encoders;
encoders = ImageCodecInfo.GetImageEncoders();
for (j = 0; j < encoders.Length; ++j)
{
if (encoders[j].MimeType == mimeType)
return encoders[j];
}
return null;
}
Result (which SO is blurring a bit itself):
I've been searching for some good examples of how to take a screenshot using ITakesScreenshot in Selenium Webdriver in C#, then to crop the image using the elements dimensions and then saving this new image. With no such luck have I found any in C#.
I have this method at the moment but every so often I get a Out of Memory exception when used in a test. It fails on the line where it tries to crop.
public void TakeScreenShotOfElement(IWebDriver _driver, string rootpath, string imgName, string element2)
{
string element3 = element2;
var element = driver.FindElement(By.XPath(element3));
Byte[] ba = ((ITakesScreenshot)driver).GetScreenshot().AsByteArray;
var ss = new Bitmap(new MemoryStream(ba));
var crop = new Rectangle(element.Location.X, element.Location.Y, element.Size.Width, element.Size.Height);
//create a new image by cropping the original screenshot
Bitmap image2 = ss.Clone(crop, ss.PixelFormat);
if (!Directory.Exists(rootpath))
{
Directory.CreateDirectory(rootpath);
}
image2.Save(String.Format("{0}\\{1}.png", rootpath, imgName), System.Drawing.Imaging.ImageFormat.Png);
}
Any help is much appreciated, thanks in advance!!!
Some of the objects you're creating are IDisposable. You need to make sure Dispose() gets called on them. As it stands they're not releasing the memory they've claimed, which is why you get the exceptions.
The easiest way to make sure these items get disposed is to wrap each of them in a using block.
I have the following snippet which loads an image from memory, resizes it, and attempts to save the resized image. I get the "A generic error occurred in GDI+" error on the resizedImage.Save(), but I can't see where an image/bitmap is being held on to. Any help would be appreciated.
using (var m = new MemoryStream(File.ReadAllBytes(fileName)))
{
using (var n = new Bitmap(m))
{
using (var newImage = n.Clone(new Rectangle(0, 0, n.Width, n.Height), PixelFormat.Format24bppRgb))
{
var filter = new ResizeBicubic(200, 200);
var resizedImage = filter.Apply(newImage);
resizedImage.Save(searchImage);
resizedImage.Dispose();
}
}
}
You cannot save the image at the same origin file. Try to change the output file. AForge keeps the origin file Open.
I am working on to upload and save a thumbnail copy of that image in a thumbnail folder.
I am using following link:
http://weblogs.asp.net/markmcdonnell/archive/2008/03/09/resize-image-before-uploading-to-server.aspx
but
newBMP.Save(directory + "tn_" + filename);
is causing exception "A generic error occurred in GDI+."
I have tried to give permission on folder, also tried to use a new separate bmp object when saving.
Edit:
protected void ResizeAndSave(PropBannerImage objPropBannerImage)
{
// Create a bitmap of the content of the fileUpload control in memory
Bitmap originalBMP = new Bitmap(fuImage.FileContent);
// Calculate the new image dimensions
int origWidth = originalBMP.Width;
int origHeight = originalBMP.Height;
int sngRatio = origWidth / origHeight;
int thumbWidth = 100;
int thumbHeight = thumbWidth / sngRatio;
int bannerWidth = 100;
int bannerHeight = bannerWidth / sngRatio;
// Create a new bitmap which will hold the previous resized bitmap
Bitmap thumbBMP = new Bitmap(originalBMP, thumbWidth, thumbHeight);
Bitmap bannerBMP = new Bitmap(originalBMP, bannerWidth, bannerHeight);
// Create a graphic based on the new bitmap
Graphics oGraphics = Graphics.FromImage(thumbBMP);
// Set the properties for the new graphic file
oGraphics.SmoothingMode = SmoothingMode.AntiAlias; oGraphics.InterpolationMode = InterpolationMode.HighQualityBicubic;
// Draw the new graphic based on the resized bitmap
oGraphics.DrawImage(originalBMP, 0, 0, thumbWidth, thumbHeight);
Bitmap newBitmap = new Bitmap(thumbBMP);
thumbBMP.Dispose();
thumbBMP = null;
// Save the new graphic file to the server
newBitmap.Save("~/image/thumbs/" + "t" + objPropBannerImage.ImageId, ImageFormat.Jpeg);
oGraphics = Graphics.FromImage(bannerBMP);
// Set the properties for the new graphic file
oGraphics.SmoothingMode = SmoothingMode.AntiAlias; oGraphics.InterpolationMode = InterpolationMode.HighQualityBicubic;
// Draw the new graphic based on the resized bitmap
oGraphics.DrawImage(originalBMP, 0, 0, bannerWidth, bannerHeight);
// Save the new graphic file to the server
bannerBMP.Save("~/image/" + objPropBannerImage.ImageId + ".jpg");
// Once finished with the bitmap objects, we deallocate them.
originalBMP.Dispose();
bannerBMP.Dispose();
oGraphics.Dispose();
}
When either a Bitmap object or an Image object is constructed from a
file, the file remains locked for the lifetime of the object. As a
result, you cannot change an image and save it back to the same file
where it originated.
http://support.microsoft.com/?id=814675
A generic error occurred in GDI+, JPEG Image to MemoryStream
Image.Save(..) throws a GDI+ exception because the memory stream is closed
http://alperguc.blogspot.in/2008/11/c-generic-error-occurred-in-gdi.html
EDIT:
just writing from memory...
save to an 'intermediary' memory stream, that should work
e.g. try this one - replace
Bitmap newBitmap = new Bitmap(thumbBMP);
thumbBMP.Dispose();
thumbBMP = null;
newBitmap.Save("~/image/thumbs/" + "t" + objPropBannerImage.ImageId, ImageFormat.Jpeg);
with something like:
string outputFileName = "...";
using (MemoryStream memory = new MemoryStream())
{
using (FileStream fs = new FileStream(outputFileName, FileMode.Create, FileAccess.ReadWrite))
{
thumbBMP.Save(memory, ImageFormat.Jpeg);
byte[] bytes = memory.ToArray();
fs.Write(bytes, 0, bytes.Length);
}
}
This error message is displayed if the path you pass to Bitmap.Save() is invalid (folder doesn't exist etc).
// Once finished with the bitmap objects, we deallocate them.
originalBMP.Dispose();
bannerBMP.Dispose();
oGraphics.Dispose();
This is a programming style that you'll regret sooner or later. Sooner is knocking on the door, you forgot one. You are not disposing newBitmap. Which keeps a lock on the file until the garbage collector runs. If it doesn't run then the second time you try to save to the same file you'll get the klaboom. GDI+ exceptions are too miserable to give a good diagnostic so serious head-scratching ensues. Beyond the thousands of googlable posts that mention this mistake.
Always favor using the using statement. Which never forgets to dispose an object, even if the code throws an exception.
using (var newBitmap = new Bitmap(thumbBMP)) {
newBitmap.Save("~/image/thumbs/" + "t" + objPropBannerImage.ImageId, ImageFormat.Jpeg);
}
Albeit that it is very unclear why you even create a new bitmap, saving thumbBMP should already be good enough. Anyhoo, give the rest of your disposable objects the same using love.
In my case the bitmap image file already existed in the system drive, so my app threw the error "A Generic error occured in GDI+".
Verify that the destination folder exists
Verify that there isn't already a file with the same name in the destination folder
Check your folder's permission where the image is saved
Right cLick on folder then go :
Properties > Security > Edit > Add-- select "everyone" and check Allow "Full Control"
I was facing the same issue A generic error occurred in GDI+ on saving while working on MVC app, I was getting this error because I was writing wrong path to save image, I corrected saving path and it worked fine for me.
img1.Save(Server.MapPath("/Upload/test.png", System.Drawing.Imaging.ImageFormat.Png);
--Above code need one change, as you need to put close brackets on Server.MapPath() method after writing its param.
Like this-
img1.Save(Server.MapPath("/Upload/test.png"), System.Drawing.Imaging.ImageFormat.Png);
GDI+ exceptions occured due to below points
Folder access issue
Missing properties of images
If folder issue - please provide access to application
If Missing properties then use below code
Code 1
using (Bitmap bmp = new Bitmap(webStream))
{
using (Bitmap newImage = new Bitmap(bmp))
{
newImage.Save("c:\temp\test.jpg", ImageFormat.Jpeg);
}
}
Code 2
using (Bitmap bmp = new Bitmap(webStream))
{
using (Bitmap newImage = new Bitmap(bmp))
{
newImage.SetResolution(bmp.HorizontalResolution, bmp.VerticalResolution);
Rectangle lockedRect = new Rectangle(0, 0, bmp.Width, bmp.Height);
BitmapData bmpData = newImage.LockBits(lockedRect, ImageLockMode.ReadWrite, bmp.PixelFormat);
bmpData.PixelFormat = bmp.PixelFormat;
newImage.UnlockBits(bmpData);
using (Graphics gr = Graphics.FromImage(newImage))
{
gr.SmoothingMode = SmoothingMode.HighQuality;
gr.InterpolationMode = InterpolationMode.HighQualityBicubic;
gr.PixelOffsetMode = PixelOffsetMode.HighQuality;
}
foreach (var item in bmp.PropertyItems)
{
newImage.SetPropertyItem(item);
}
newImage.Save("c:\temp\test.jpg", ImageFormat.Jpeg);
}
}
Different between code 1 and code 2
Code - 1 : it will just create image and can open it on normal image viewer
the image can't open in Photoshop
Image size will be double
Code - 2 : to open image in image edition tools use code
by using code 1 it just create images but it not assign image marks.
I always check/test these:
Does the path + filename contain illegal characters for the given filesystem?
Does the file already exist? (Bad)
Does the path already exist? (Good)
If the path is relative: am I expecting it in the right parent directory (mostly bin/Debug ;-) )?
Is the path writable for the program and as which user does it run? (Services can be tricky here!)
Does the full path really, really not contain illegal chars? (some unicode chars are close to invisible)
I never had any problems with Bitmap.Save() apart from this list.
I had a different issue with the same exception.
In short:
Make sure that the Bitmap's object Stream is not being disposed before calling .Save .
Full story:
There was a method that returned a Bitmap object, built from a MemoryStream in the following way:
private Bitmap getImage(byte[] imageBinaryData){
.
.
.
Bitmap image;
using (var stream = new MemoryStream(imageBinaryData))
{
image = new Bitmap(stream);
}
return image;
}
then someone used the returned image to save it as a file
image.Save(path);
The problem was that the original stream was already disposed when trying to save the image, throwing the GDI+ exeption.
A fix to this problem was to return the Bitmap without disposing the stream itself but the returned Bitmap object.
private Bitmap getImage(byte[] imageBinaryData){
.
.
.
Bitmap image;
var stream = new MemoryStream(imageBinaryData))
image = new Bitmap(stream);
return image;
}
then:
using (var image = getImage(binData))
{
image.Save(path);
}
I got it working using FileStream, get help from these
http://alperguc.blogspot.in/2008/11/c-generic-error-occurred-in-gdi.html
http://csharpdotnetfreak.blogspot.com/2010/02/resize-image-upload-ms-sql-database.html
System.Drawing.Image imageToBeResized = System.Drawing.Image.FromStream(fuImage.PostedFile.InputStream);
int imageHeight = imageToBeResized.Height;
int imageWidth = imageToBeResized.Width;
int maxHeight = 240;
int maxWidth = 320;
imageHeight = (imageHeight * maxWidth) / imageWidth;
imageWidth = maxWidth;
if (imageHeight > maxHeight)
{
imageWidth = (imageWidth * maxHeight) / imageHeight;
imageHeight = maxHeight;
}
Bitmap bitmap = new Bitmap(imageToBeResized, imageWidth, imageHeight);
System.IO.MemoryStream stream = new MemoryStream();
bitmap.Save(stream, System.Drawing.Imaging.ImageFormat.Jpeg);
stream.Position = 0;
byte[] image = new byte[stream.Length + 1];
stream.Read(image, 0, image.Length);
System.IO.FileStream fs
= new System.IO.FileStream(Server.MapPath("~/image/a.jpg"), System.IO.FileMode.Create
, System.IO.FileAccess.ReadWrite);
fs.Write(image, 0, image.Length);
For me it was a permission problem. Somebody removed write permissions on the folder for the user account under which the application was running.
Create folder path image/thumbs on your hard disk => Problem solved!
I used below logic while saving a .png format. This is to ensure the file is already existing or not.. if exist then saving it by adding 1 in the filename
Bitmap btImage = new Bitmap("D:\\Oldfoldername\\filename.png");
string path="D:\\Newfoldername\\filename.png";
int Count=0;
if (System.IO.File.Exists(path))
{
do
{
path = "D:\\Newfoldername\\filename"+"_"+ ++Count + ".png";
} while (System.IO.File.Exists(path));
}
btImage.Save(path, System.Drawing.Imaging.ImageFormat.Png);
I encountered this error while trying to convert Tiff images to Jpeg. For me the issue stemmed from the tiff dimensions being too large. Anything up to around 62000 pixels was fine, anything above this size produced the error.
for me it was a path issue when saving the image.
int count = Directory.EnumerateFiles(System.Web.HttpContext.Current.Server.MapPath("~/images/savedimages"), "*").Count();
var img = Base64ToImage(imgRaw);
string path = "images/savedimages/upImages" + (count + 1) + ".png";
img.Save(Path.Combine(System.Web.HttpContext.Current.Server.MapPath(path)));
return path;
So I fixed it by adding the following forward slash
String path = "images/savedimages....
should be
String path = "/images/savedimages....
Hope that helps anyone stuck!
from msdn: public void Save (string filename); which is quite surprising to me because we dont just have to pass in the filename, we have to pass the filename along with the path for example: MyDirectory/MyImage.jpeg, here MyImage.jpeg does not actually exist yet, but our file will be saved with this name.
Another important point here is that if you are using Save() in a web application then use Server.MapPath() along with it which basically just returns the physical path for the virtual path which is passed in. Something like: image.Save(Server.MapPath("~/images/im111.jpeg"));
I use this solution
int G = 0;
private void toolStripMenuItem17_Click(object sender, EventArgs e)
{
Directory.CreateDirectory("picture");// هذه العملية للرسم بدون ان يحذف بقية الرسومات
G = G + 1;
FormScreen();
memoryImage1.Save("picture\\picture" + G.ToString() + ".jpg");
pictureBox1.Image = Image.FromFile("picture\\picture" + G.ToString() + ".jpg");
}
The code below solved my problem
pictureBox1.Image=myImage;
Bitmap bmp = new Bitmap(pictureBox1.Image);
bmp.Save("C:\\Users/super/Desktop/robin.jpg");
I am using an Epson Perfection V700 scanner and selecting the following options when scanning using their tool:
ICM Color correction (source: EPSON-Standard and target: sRGB)
Unsharp Mask (medium)
That produces this image:
Now my problem is this - I actually need to interact with this scanner using TWAIN .Net and when I do so, the image I get back is this:
Aside: I unselected the aforementioned two options and scanned again with the Epson and got a very similar image to what I get through TWAIN.
So I figure that perhaps these are post processing steps that I can do myself on the image (maybe they are done in the hardware somehow though, I don't know).
I am using EmguCV so first of all I created an extension method that applies the ICM (I struggled to find any documentation for this, so it is a bit of a guess and maybe I am wrong straight away but I got the information from here: The bitmap transform class and it seems to make a difference to the image):
public static Image<Bgr, TDepth> ApplyIcm<TDepth>(
this Image<Bgr, TDepth> source,
string sourceIcm,
string targetIcm)
where TDepth : new()
{
var target = source.CopyBlank();
using (source)
{
using (var b = source.Bitmap)
{
using (var memory = new MemoryStream())
{
b.Save(memory, ImageFormat.Bmp);
memory.Position = 0;
var bitmapImage = new BitmapImage();
bitmapImage.BeginInit();
bitmapImage.StreamSource = memory;
bitmapImage.CacheOption = BitmapCacheOption.OnLoad;
bitmapImage.EndInit();
var ccb = new ColorConvertedBitmap();
ccb.BeginInit();
ccb.Source = bitmapImage;
ccb.SourceColorContext =
new ColorContext(new Uri(sourceIcm));
ccb.DestinationColorContext =
new ColorContext(new Uri(targetIcm));
ccb.EndInit();
var encoder = new BmpBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(ccb));
using (var ms = new MemoryStream())
{
encoder.Save(ms);
target.Bitmap = new Bitmap(ms);
}
}
}
}
return target;
}
Then I looked at that unsharpen thing and came across this question: How to sharpen an image in OpenCV? which says:
You use a gaussian smoothing filter and subtract the smoothed version from the original image
(I also checked this question to find out what the equivalent emgucv call is Why might EmguCV Gaussian blur not return identical results as OpenCV Gaussian blur?) and came up with this additional extension method:
public static Image<Bgr, TDepth> UnsharpMask<TDepth>(
this Image<Bgr, TDepth> source,
Size kernelSize,
int kernelHoritonalStandardDeviation,
int kernelVerticalStandardDeviation,
double alpha,
double beta,
double gamma)
where TDepth : new()
{
Image<Bgr, TDepth> ret = source.CopyBlank();
CvInvoke.cvSmooth(source,
ret,
SMOOTH_TYPE.CV_GAUSSIAN,
kernelSize.Width,
kernelSize.Height,
kernelHoritonalStandardDeviation,
kernelVerticalStandardDeviation);
CvInvoke.cvAddWeighted(source, alpha, ret, beta, gamma, ret);
return ret;
}
Now I call it like so:
string sourceIcm = #"C:\Windows\System32\spool\drivers\color\ewrgb18.icm";
string targetIcm = #"C:\Windows\System32\spool\drivers\color\ewsrgb.icm";
using(var im = new Image<Bgr, byte>("out.bmp"))
{
using (var icmmed = im.ApplyIcm(sourceIcm, targetIcm))
{
using (var ret = icmmed.UnsharpMask(new Size(0, 0), 5, 5, 2.4, -1.5, 0))
{
ret.Save("ret.bmp");
}
}
}
and this is the result:
Not very good! :-(
I have fiddled with the parameters endlessly but I just cannot work out how (or even if) I can achieve the same result as the Epson tool.
So, my question is:
Does anyone know if it is possible to achieve a result using opencv/emgucv (or even TWAIN - I had a look through the documentation for that and tried adjusting some of the capability parameters but I just made the image worse) that is similar in sharpness to the original image above or is there another technique I should try (could it be that I would need to know some details about the hardware itself in order to achieve correct sharpening)?
I think you should know how using WIA (Windows Image Acquisition) in your project, you may don't need to get access to hardware using opencv. WIA is used for integrating with webcams and scanners. Or, you can use TWAIN as you mentioned
have a look at these examples they could by helpful for your project:
using WIA
and
using TWAIN
Concerning the sharpening, you can use opencv functionality at software level, as another choice to solve your problem