I'm trying to upload a byte array to a mysql column type mediumblob. after the upload I see the blob has a size in kilobytes, however, when I download the file and view it in notepad... it's just empty white space.
here's how I am getting my bytes from an image PNG file:
private async void artworkFileBTN_Click(object sender, RoutedEventArgs e)
{
FileOpenPicker openPicker = new FileOpenPicker();
openPicker.ViewMode = PickerViewMode.Thumbnail;
openPicker.SuggestedStartLocation = PickerLocationId.PicturesLibrary;
openPicker.FileTypeFilter.Add(".png");
artworkfile = await openPicker.PickSingleFileAsync();
if (artworkfile != null)
{
artworkSet = true;
//var stream = await musicfile.OpenAsync(Windows.Storage.FileAccessMode.Read);
artworkFileBTN.Content = artworkfile.DisplayName;
var stream = await artworkfile.OpenAsync(FileAccessMode.Read);
var streamBytes = await artworkfile.OpenStreamForReadAsync();
var bytes = new byte[(int)streamBytes.Length];
ArtworkRawData =bytes;
}
else
{
//
}
}
can anyone tell me why my array contains only whitespace?
Solved.
byte[] result;
using (Stream streambytes = await artworkfile.OpenStreamForReadAsync())
{
using (var memoryStream = new MemoryStream())
{
streambytes.CopyTo(memoryStream);
result = memoryStream.ToArray();
}
}
ArtworkRawData = result;
Related
if (!CrossMedia.Current.IsPickPhotoSupported)
{
await Application.Current.MainPage.DisplayAlert("Photos Not Supported", ":( Permission not granted to photos.", "OK");
return;
}
var file = await Plugin.Media.CrossMedia.Current.PickPhotoAsync(new Plugin.Media.Abstractions.PickMediaOptions
{
PhotoSize = Plugin.Media.Abstractions.PhotoSize.Medium,
});
if (file == null)
return;
var tmpSrc = ImageSource.FromStream(() =>
{
var stream = file.GetStream();
file.Dispose();
return stream;
});
ImageSource toBeConverted = tmpSrc;
I want the variable toBeConverted to be converted into Byte[] so
that I can send it to my webapi ...
ImageSource is a way to provide a source image for Xamarin.Forms.Image to show some content. If you're already showing something on the screen your Image view was populated with data that came from elsewhere, such as a file or resource or stored in an array in memory... or however else you got that in the first place. Instead of trying to get that data back from ImageSource you can keep a reference to it and upload it as needed.
So you could get the byte array from the file after you pick the photo.
var file = await Plugin.Media.CrossMedia.Current.PickPhotoAsync(new Plugin.Media.Abstractions.PickMediaOptions
{
PhotoSize = Plugin.Media.Abstractions.PhotoSize.Medium,
});
if (file == null)
return;
var bytes = File.ReadAllBytes(file.Path); // you could get the byte[] here from the file path.
This code also worked for me ...
private async void Capture()
{
if (!CrossMedia.Current.IsCameraAvailable || !CrossMedia.Current.IsTakePhotoSupported)
{
await Application.Current.MainPage.DisplayAlert("No Camera", ":( No camera available.", "OK");
return;
}
var file = await CrossMedia.Current.TakePhotoAsync(new Plugin.Media.Abstractions.StoreCameraMediaOptions
{
Directory = "Test",
SaveToAlbum = true,
CompressionQuality = 75,
CustomPhotoSize = 50,
PhotoSize = PhotoSize.Medium,
DefaultCamera = CameraDevice.Front
});
if (file == null)
return;
var stream = file.GetStream();
if (stream != null)
{
var StreamByte = ReadAllBytes(stream);
var NewStream = new MemoryStream(StreamByte);
// stream = mystream;
Device.BeginInvokeOnMainThread(() => {
ImageSource = ImageSource.FromStream(() => NewStream);
});
student.ProfilePicture = StreamByte;
}
}
public byte[] ReadAllBytes(Stream instream)
{
if (instream is MemoryStream)
return ((MemoryStream)instream).ToArray();
using (var memoryStream = new MemoryStream())
{
instream.CopyTo(memoryStream);
return memoryStream.ToArray();
}
}
I am making a UWP app where i want to pick a user signature scanned by the user and make the picture transparent.
now first things first:
I am using FileOpenPicker to pick the storage file.
Work tried by me
public async void Button_AddSign_Click(object sender, RoutedEventArgs e)
{
try
{
var _filePicker = new FileOpenPicker();
_filePicker.SuggestedStartLocation = PickerLocationId.Desktop;
_filePicker.ViewMode = PickerViewMode.Thumbnail;
_filePicker.FileTypeFilter.Add(".png");
IStorageFile _file = await _filePicker.PickSingleFileAsync();
StorageFolder storageFolder = await ApplicationData.Current.LocalFolder.GetFolderAsync(CurrentUser);
if (_file != null)
{
StorageFile storageFile = await _file.CopyAsync(storageFolder, "Signature.png");
await MakeSignTransparentAsync(storageFile);
}
}
catch{Exception ex}
}
public static async Task MakeSignTransparentAsync(StorageFile Inputfile)
{
var memStream = new InMemoryRandomAccessStream();
using (IRandomAccessStream fileStream = await Inputfile.OpenAsync(FileAccessMode.ReadWrite))
{
BitmapDecoder decoder = await BitmapDecoder.CreateAsync(fileStream);
BitmapEncoder encoder = await BitmapEncoder.CreateForTranscodingAsync(memStream, decoder);
encoder.BitmapTransform.ScaledWidth = 600;
encoder.BitmapTransform.ScaledHeight = 200;
await encoder.FlushAsync();
memStream.Seek(0);
fileStream.Seek(0);
fileStream.Size = 0;
await RandomAccessStream.CopyAsync(memStream, fileStream);
memStream.Dispose();
}
Bitmap bmp;
using (MemoryStream ms = new MemoryStream(memStream)) //Getting an error at this line
{
bmp = new Bitmap(ms);
}
bmp.MakeTransparent();
bmp.Save(bmpInput.Path + "test.png", ImageFormat.Png);
}
Error:
Argument 1: cannot convert from 'Windows.Storage.Streams.InMemoryRandomAccessStream' to 'byte[]
Any help is appreciated.
If there is another way around other than this that is also appreciated.
Found a solution using a library ImageMagick
using ImageMagick;
public static async Task MakeSignTransparentAsync(StorageFile bmpInput)
{
using (var img = new MagickImage(bmpInput.Path))
{
// -fuzz XX%
img.ColorFuzz = new Percentage(10);
// -transparent white
img.Transparent(MagickColors.White);
img.Write(bmpInput.Path);
}
}
I have captured picture using
cameracaptureui and I have the image in image control.
Now the problem is how to save this captured image to my database.?
normally i did this task in windows form via converting image to byets. but now bit confused in UWP.
thanks in advance
What I have tried:`
private async void button_Copy_Click(object sender, RoutedEventArgs e)
{
//create camera instance with camera capture ui
CameraCaptureUI captureUI = new CameraCaptureUI();
captureUI.PhotoSettings.Format = CameraCaptureUIPhotoFormat.Jpeg;
captureUI.PhotoSettings.CroppedSizeInPixels = new Size(200, 200);
StorageFile photo = await captureUI.CaptureFileAsync(CameraCaptureUIMode.Photo);
if (photo == null)
{
// User cancelled photo capture
return;
}
//return the captured results to fram via bitmap
IRandomAccessStream stream = await photo.OpenAsync(FileAccessMode.Read);
BitmapDecoder decoder = await BitmapDecoder.CreateAsync(stream);
SoftwareBitmap softwareBitmap = await decoder.GetSoftwareBitmapAsync();
SoftwareBitmap softwareBitmapBGR8 = SoftwareBitmap.Convert(softwareBitmap,BitmapPixelFormat.Bgra8, BitmapAlphaMode.Premultiplied);
SoftwareBitmapSource bitmapSource = new SoftwareBitmapSource();
await bitmapSource.SetBitmapAsync(softwareBitmapBGR8);
imageControl.Source = bitmapSource;
}
Convert Image to Base64 and save it to mysql database. Save Captured Image to Application Local Folder and Convert it to Base64.
C# code:
using System.Threading.Tasks;
using Windows.Storage;
using Windows.Storage.Streams;
private async void btn_Click(object sender, RoutedEventArgs e)
{
var file = await StorageFile.GetFileFromApplicationUriAsync(new Uri("ms-appdata:///local/" + "your_image_name.png"));
string base64image = await _encodeToBase64(file.Path);
}
public async Task<string> _encodeToBase64(string filePath)
{
string encode = String.Empty;
if (!string.IsNullOrEmpty(filePath))
{
StorageFile file = await StorageFile.GetFileFromPathAsync(filePath);
IBuffer buffer = await FileIO.ReadBufferAsync(file);
DataReader reader = DataReader.FromBuffer(buffer);
byte[] fileContent = new byte[reader.UnconsumedBufferLength];
reader.ReadBytes(fileContent);
encode = Convert.ToBase64String(fileContent);
}
return encode;
}
For the past week I've been researching as much as i can on how to add the ability to crop a profile image in my windows store app. So far I have looked at the Microsoft solution to this but have decided to go a different route. I downloaded a control from NuGet called XamlCropControl. It works pretty well for the UI and even give me information like Original Height/Width The position of the cropped top/bottom/left/right/width/height all within the xaml control. my question is as how to take that information and crop the the image using WriteableBitmapEx. So far this is my code and i'm having a problem.
private async void ProfilePhotoImageClick(object sender, TappedRoutedEventArgs e)
{
FileOpenPicker openPicker = new FileOpenPicker();
openPicker.ViewMode = PickerViewMode.Thumbnail;
openPicker.SuggestedStartLocation = PickerLocationId.PicturesLibrary;
openPicker.FileTypeFilter.Add(".jpg");
openPicker.FileTypeFilter.Add(".jpeg");
openPicker.FileTypeFilter.Add(".png");
StorageFile file = await openPicker.PickSingleFileAsync();
if (file != null)
{
using (Windows.Storage.Streams.IRandomAccessStream fileStream = await file.OpenAsync(Windows.Storage.FileAccessMode.Read))
{
Windows.UI.Xaml.Media.Imaging.BitmapImage bitmapImage = new BitmapImage();
bitmapImage.SetSource(fileStream);
BackgroundLogo.Visibility = Windows.UI.Xaml.Visibility.Collapsed;
PhotoUploadCropper.Opacity = 1;
PhotoUploadCropper.ImageSource = bitmapImage;
ProfileSetupStackPanel.Visibility = Windows.UI.Xaml.Visibility.Collapsed;
imagetoResize = bitmapImage;
}
}
}
BitmapImage imagetoResize;
private void AcceptPhotoImageCropClick(object sender, RoutedEventArgs e)
{
WriteableBitmap bmp = new WriteableBitmap(0,0).FromContent(imagetoResize);
var croppedBmp = bmp.Crop(0, 0, bmp.PixelWidth / 2, bmp.PixelHeight / 2);
croppedBmp.SaveToMediaLibrary("ProfilePhoto.jpg");
}
PhotoUploadCropper is the xamlcropcontrol.
This is the information from xamlcropcontrol
This is the problem im having
It tells me there is no deffinition for FromContent if i have the (imagetoResize) there but if i remove it i get no error. After all the cropping is done it will be uploading to azure blob storage which i have already setup.
Edit: Works like this.
private async void ProfilePhotoImageClick(object sender, TappedRoutedEventArgs e)
{
FileOpenPicker openPicker = new FileOpenPicker();
openPicker.ViewMode = PickerViewMode.Thumbnail;
openPicker.SuggestedStartLocation = PickerLocationId.PicturesLibrary;
openPicker.FileTypeFilter.Add(".jpg");
openPicker.FileTypeFilter.Add(".jpeg");
openPicker.FileTypeFilter.Add(".png");
StorageFile file = await openPicker.PickSingleFileAsync();
if (file != null)
{
using (IRandomAccessStream fileStream = await file.OpenAsync(FileAccessMode.Read))
{
BitmapImage bitmapImage = new BitmapImage();
await bitmapImage.SetSourceAsync(fileStream);
fileclone = file;
BackgroundLogo.Visibility = Windows.UI.Xaml.Visibility.Collapsed;
PhotoUploadCropper.IsEnabled = true;
PhotoUploadCropper.Opacity = 1;
PhotoUploadCropper.ImageSource = bitmapImage;
ProfileSetupStackPanel.Visibility = Windows.UI.Xaml.Visibility.Collapsed;
}
}
}
StorageFile fileclone;
async Task<WriteableBitmap> LoadBitmap(StorageFile file)
{
int cropx = PhotoUploadCropper.CropTop;
int cropy = PhotoUploadCropper.CropLeft;
int cropW = PhotoUploadCropper.CropWidth;
int cropH = PhotoUploadCropper.CropHeight;
using (IRandomAccessStream fileStream = await file.OpenAsync(FileAccessMode.Read))
{
var bmp = await BitmapFactory.New(1, 1).FromStream(fileStream);
var croppedBmp = bmp.Crop(cropy, cropx, cropW, cropH);
var resizedcroppedBmp = croppedBmp.Resize(200, 200, WriteableBitmapExtensions.Interpolation.Bilinear);
return resizedcroppedBmp;
}
}
private async void AcceptPhotoImageCropClick(object sender, RoutedEventArgs e)
{
var CroppedBMP = await CropBitmap(fileclone);
using (IRandomAccessStream fileStream = new InMemoryRandomAccessStream())
{
string filename = Path.GetRandomFileName() + ".JPG";
var file = await Windows.Storage.ApplicationData.Current.TemporaryFolder.CreateFileAsync(filename, CreationCollisionOption.GenerateUniqueName);
using (IRandomAccessStream stream = await file.OpenAsync(FileAccessMode.ReadWrite))
{
BitmapEncoder encoder = await BitmapEncoder.CreateAsync(BitmapEncoder.JpegEncoderId, stream);
Stream pixelStream = CroppedBMP.PixelBuffer.AsStream();
byte[] pixels = new byte[pixelStream.Length];
await pixelStream.ReadAsync(pixels, 0, pixels.Length);
encoder.SetPixelData(BitmapPixelFormat.Bgra8, BitmapAlphaMode.Ignore, (uint)CroppedBMP.PixelWidth, (uint)CroppedBMP.PixelHeight, 96.0, 96.0, pixels);
await encoder.FlushAsync();
}
ProfilePhotoButtonsGrid.Visibility = Windows.UI.Xaml.Visibility.Collapsed;
BackgroundLogo.Visibility = Windows.UI.Xaml.Visibility.Visible;
PhotoUploadCropper.IsEnabled = false;
PhotoUploadCropper.Opacity = 0;
ProfileSetupStackPanel.Visibility = Windows.UI.Xaml.Visibility.Visible;
if (fileStream != null)
{
UploadFile(file);
}
}
}
You will have to use the WBX WinRT APIs for this. Looks like you are trying the WP / Silverlight methods.
Try this:
async Task<WriteableBitmap> LoadBitmap(string path)
{
Uri imageUri = new Uri(BaseUri, path);
var bmp = await BitmapFactory.New(1, 1).FromContent(imageUri);
return bmp;
}
Note it takes an URI. In your case you can rather use the IRandomAccessStream directly:
var bmp = await BitmapFactory.New(1, 1).FromStream(fileStream);
In WindowsStoreApps i want to convert an Local Image from solution explorer to byte array and then to base64 string.please guide me.The code I have tried so far is as below.
public async Task<string> ToBase64()
{
Byte[] ByteResult = null;
string bs64 = null;
if (url != null)
{
HttpClient client = new HttpClient();
ByteResult = await client.GetByteArrayAsync(url);
}
bs64 = Convert.ToBase64String(ByteResult);
return bs64;
}
Suppose you want to convert an image named MyImage.png from Assets folder then below code will return the base64 string of that image.
private async Task DoWork()
{
var file = await StorageFile.GetFileFromApplicationUriAsync(new Uri("ms-appx:///Assets/MyImage.png"));
var b64 = await ConvertStorageFileToBase64String(file);
}
private async Task<string> ConvertStorageFileToBase64String(StorageFile File)
{
var stream = await File.OpenReadAsync();
using (var dataReader = new DataReader(stream))
{
var bytes = new byte[stream.Size];
await dataReader.LoadAsync((uint)stream.Size);
dataReader.ReadBytes(bytes);
return Convert.ToBase64String(bytes);
}
}
Try this piece of code
StorageFile file = <Your File>;
var bytes = new Byte[0];
using (IRandomAccessStream fileStream = await file.OpenAsync(FileAccessMode.Read))
{
var reader = new DataReader(fileStream.GetInputStreamAt(0));
bytes = new Byte[fileStream.Size];
await reader.LoadAsync((uint)fileStream.Size);
reader.ReadBytes(bytes);
}
string imageInStringFormat = Convert.ToBase64String(bytes);