ScanFile isn't strictly required, but if you're testing your program by immediately checking the photo library, it helps a lot by updating the library gallery view. The Capabilities section of the Package. Here's the Encode method of SKImage again:. SKEncodedImageFormat is an enumeration with members that refer to eleven bitmap file formats, some of which are rather obscure:.
As you'll see shortly, only three of these file formats Jpeg , Png , and Webp are actually supported by SkiaSharp. To save an SKBitmap object named bitmap to the user's photo library, you also need a member of the SKEncodedImageFormat enumeration named imageFormat and for lossy formats an integer quality variable.
You can use the following code to save that bitmap to a file with the name filename in the folder folder:. The Encode method writes the encoded bitmap file into that stream. The comments in that code refer to some error checking you might need to perform. The Save File Formats page in the SkiaSharpFormsDemos application uses similar code to allow you to experiment with saving a bitmap in the various formats.
It has a Picker for a member of the SKEncodedImageFormat enumeration, a Slider for the quality argument for lossy bitmap formats, two Entry views for a filename and folder name, and a Button for saving the file. The code-behind file loads a bitmap resource and uses the SKCanvasView to display it. That bitmap never changes. The SelectedIndexChanged handler for the Picker modifies the filename with an extension that is the same as the enumeration member:.
The Clicked handler for the Button does all the real work. The two Entry views furnish folder and file names for the SavePhotoAsync method. Most of this method is devoted to handling problems or errors. If Encode creates an empty array, it means that the particular file format isn't supported.
If SavePhotoAsync returns false , then the file wasn't successfully saved. For all the other formats, the Encode method writes nothing into the stream and the resultant byte array is empty. The bitmap that the Save File Formats page saves is pixels square. With 4 bytes per pixel, that's a total of 1,, bytes in memory. The following table shows the file size for various combinations of file format and quality:. One common use of a bitmap is in drawing programs, where it functions as something called a shadow bitmap.
All the drawing is retained on the bitmap, which is then displayed by the program. Format24bppRgb ;. LockBits new Rectangle 0, 0, bmp. Width, bmp. Height , ImageLockMode. WriteOnly, bmp. PixelFormat ;. Scan0 Marshal. Copy data, 0, bmpData. Scan0, data. Length ;.
UnlockBits bmpData ;. This code snippet is working fine. I tried many approaches to display it , but I could not able to display as mentioned below:. Seek 0, SeekOrigin. Length]; byteArray. Connect and share knowledge within a single location that is structured and easy to search. Stack Overflow for Teams — Collaborate and share knowledge with a private group.
Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Ask Question. Asked 10 years, 10 months ago. Active 9 years, 7 months ago. Viewed 9k times. Image that is used. Ty i have last question and i think it will be end. When i used your code I get this error while debug. An unhandled exception of type 'System. FromStream method is not a valid image. The problem here is that its not a stream of raw RGB as in question.
To retrieve data no dimensions are given, it saves images just like any object can saved where the object itself allready was a image with makeup ea dimensions pixelformat etc. Show 3 more comments. In addition, you can simply convert byte array to Bitmap. FromFile filePath ;. Majedur Majedur 2, 22 22 silver badges 31 31 bronze badges. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password. Post as a guest Name.
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