CameraCaptureTask から画像を取得していますが、保存する前に画像をもっと小さくしたいと考えています。幅と高さは自動的に最高の解像度に設定されますが、これは必要以上のものです。エラーが発生していますが、画像を取得し、寸法を変更してから保存しようとしています。
オリジナル
MainPage.xaml.cs
private void cameraTask_Completed(object sender, PhotoResult e)
{
if (e.TaskResult == TaskResult.OK)
{
BitmapImage bmi = new BitmapImage();
bmi.SetSource(e.ChosenPhoto);
//MessageBox.Show(bmi.PixelWidth.ToString() + "x" + bmi.PixelHeight.ToString());
var gcd = GCD(bmi.PixelWidth, bmi.PixelHeight);
var result = string.Format("{0}:{1}", bmi.PixelWidth / gcd, bmi.PixelHeight / gcd);
WriteableBitmap wb;
Stream stream;
switch (result)
{
case "3:4":
wb = new WriteableBitmap(480,640);
break;
case "4:3":
wb = new WriteableBitmap(640,480);
break;
case "9:16":
wb = new WriteableBitmap(448, 800);
break;
case "16:9":
wb = new WriteableBitmap(800, 448);
break;
default:
wb = null;
return;
}
//Set the wb to the original stream?
wb.SetSource(e.ChosenPhoto);
//Convert the wb to a stream for saving
stream = new MemoryStream(wb.ToByteArray());
//Need to replace the following line with the new image stream for saving?
//var capturedPicture = new CapturedPicture(e.OriginalFileName, e.ChosenPhoto);
var capturedPicture = new CapturedPicture(e.OriginalFileName, stream);
}
}
public int GCD(int a, int b)
{
while (a != 0 && b != 0)
{
if (a > b)
a %= b;
else
b %= a;
}
if (a == 0)
return b;
else
return a;
}
編集: 新しい実装
private void cameraTask_Completed(object sender, PhotoResult e)
{
if (e.TaskResult == TaskResult.OK)
{
BitmapImage bmi = new BitmapImage();
bmi.SetSource(e.ChosenPhoto);
var gcd = GCD(bmi.PixelWidth, bmi.PixelHeight);
var result = string.Format("{0}:{1}", bmi.PixelWidth / gcd, bmi.PixelHeight / gcd);
WriteableBitmap wb = new WriteableBitmap(bmi);
Stream stream = new MemoryStream();
switch (result)
{
case "3:4":
wb.SaveJpeg(stream, 480, 640, 0, 100);
break;
case "4:3":
wb.SaveJpeg(stream, 640, 480, 0, 100);
break;
case "9:16":
wb.SaveJpeg(stream, 448, 800, 0, 100);
break;
case "16:9":
wb.SaveJpeg(stream, 800, 448, 0, 100);
break;
default:
wb = null;
return;
}
stream.Seek(0, SeekOrigin.Begin);
//var capturedPicture = new CapturedPicture(e.OriginalFileName, e.ChosenPhoto);
var capturedPicture = new CapturedPicture(e.OriginalFileName, stream);