//Download and resize image
public async Task <Stream> DownloadResizeImage(Uri downloadUri, uint maxWidth, uint maxHeight)
{
try
{
//Check local cache
Stream imageStream = null;
string cacheFile = Path.Combine("Cache", AVFunctions.StringToHash(downloadUri.ToString()));
if (AVFiles.File_Exists(cacheFile, true))
{
//Load cached image
imageStream = AVFiles.File_LoadStream(cacheFile, true);
Debug.WriteLine("Windows cache image length: " + imageStream.Length);
}
else
{
//Download image
imageStream = await AVDownloader.DownloadStreamAsync(8000, null, null, downloadUri);
//Save cache image
AVFiles.File_SaveStream(cacheFile, imageStream, true, true);
Debug.WriteLine("Windows download image length: " + imageStream.Length);
}
//Decode image
if (imageStream.CanSeek)
{
imageStream.Position = 0;
}
BitmapDecoder bitmapDecoder = await BitmapDecoder.CreateAsync(imageStream.AsRandomAccessStream());
//Calculate size
uint resizeWidth = 0;
uint resizeHeight = 0;
uint originalWidth = bitmapDecoder.PixelWidth;
uint originalHeight = bitmapDecoder.PixelHeight;
float originalAspect = (float)originalWidth / (float)originalHeight;
if (originalWidth > maxWidth)
{
resizeWidth = maxWidth;
resizeHeight = (uint)(maxWidth / originalAspect);
}
else if (originalHeight > maxHeight)
{
resizeWidth = (uint)(maxHeight / originalAspect);
resizeHeight = maxHeight;
}
else
{
resizeWidth = originalWidth;
resizeHeight = originalHeight;
}
//Debug.WriteLine("Resizing image to: " + resizeWidth + "w/" + resizeHeight + "h/" + originalAspect + "a");
//Resize image
InMemoryRandomAccessStream resizeStream = new InMemoryRandomAccessStream();
BitmapEncoder bitmapEncoder = await BitmapEncoder.CreateForTranscodingAsync(resizeStream, bitmapDecoder);
bitmapEncoder.BitmapTransform.ScaledWidth = resizeWidth;
bitmapEncoder.BitmapTransform.ScaledHeight = resizeHeight;
await bitmapEncoder.FlushAsync();
//Dispose resources
imageStream.Dispose();
//Convert stream
return(resizeStream.AsStream());
}
catch (Exception ex)
{
Debug.WriteLine("Failed to download and resize image: " + ex.Message);
return(null);
}
}
//Download and resize image
public async Task <Stream> DownloadResizeImage(Uri downloadUri, uint maxWidth, uint maxHeight)
{
try
{
//Check local cache
Stream imageStream = null;
string cacheFile = System.IO.Path.Combine("Cache", AVFunctions.StringToHash(downloadUri.ToString()));
if (AVFiles.File_Exists(cacheFile, true))
{
//Load cached image
imageStream = AVFiles.File_LoadStream(cacheFile, true);
Debug.WriteLine("Android cache image length: " + imageStream.Length);
}
else
{
//Download image
imageStream = await AVDownloader.DownloadStreamAsync(8000, null, null, downloadUri);
//Save cache image
AVFiles.File_SaveStream(cacheFile, imageStream, true, true);
Debug.WriteLine("Android download image length: " + imageStream.Length);
}
//Decode image
if (imageStream.CanSeek)
{
imageStream.Position = 0;
}
Bitmap originalImage = await BitmapFactory.DecodeStreamAsync(imageStream);
//Calculate size
uint resizeWidth = 0;
uint resizeHeight = 0;
uint originalWidth = (uint)originalImage.Width;
uint originalHeight = (uint)originalImage.Height;
float originalAspect = (float)originalWidth / (float)originalHeight;
if (originalWidth > maxWidth)
{
resizeWidth = maxWidth;
resizeHeight = (uint)(maxWidth / originalAspect);
}
else if (originalHeight > maxHeight)
{
resizeWidth = (uint)(maxHeight / originalAspect);
resizeHeight = maxHeight;
}
else
{
resizeWidth = originalWidth;
resizeHeight = originalHeight;
}
//Debug.WriteLine("Resizing image to: " + resizeWidth + "w/" + resizeHeight + "h/" + originalAspect + "a");
//Resize image
Bitmap resizeImage = Bitmap.CreateScaledBitmap(originalImage, (int)resizeWidth, (int)resizeHeight, true);
MemoryStream memoryStream = new MemoryStream();
resizeImage.Compress(Bitmap.CompressFormat.Png, 100, memoryStream);
if (memoryStream.CanSeek)
{
memoryStream.Position = 0;
}
//Dispose resources
imageStream.Dispose();
originalImage.Dispose();
resizeImage.Dispose();
//Return stream
return(memoryStream);
}
catch (Exception ex)
{
Debug.WriteLine("Failed to download and resize image: " + ex.Message);
return(null);
}
}
//Download and resize image
public async Task <Stream> DownloadResizeImage(Uri downloadUri, uint maxWidth, uint maxHeight)
{
try
{
//Check local cache
Stream imageStream = null;
string cacheFile = Path.Combine("Cache", AVFunctions.StringToHash(downloadUri.ToString()));
if (AVFiles.File_Exists(cacheFile, true))
{
//Load cached image
imageStream = AVFiles.File_LoadStream(cacheFile, true);
Debug.WriteLine("Apple cache image length: " + imageStream.Length);
}
else
{
//Download image
imageStream = await AVDownloader.DownloadStreamAsync(8000, null, null, downloadUri);
//Save cache image
AVFiles.File_SaveStream(cacheFile, imageStream, true, true);
Debug.WriteLine("Apple download image length: " + imageStream.Length);
}
//Decode image
if (imageStream.CanSeek)
{
imageStream.Position = 0;
}
NSData imageNsData = NSData.FromStream(imageStream);
UIImage originalImage = UIImage.LoadFromData(imageNsData);
//Calculate size
uint resizeWidth = 0;
uint resizeHeight = 0;
uint originalWidth = (uint)originalImage.Size.Width;
uint originalHeight = (uint)originalImage.Size.Height;
float originalAspect = (float)originalWidth / (float)originalHeight;
if (originalWidth > maxWidth)
{
resizeWidth = maxWidth;
resizeHeight = (uint)(maxWidth / originalAspect);
}
else if (originalHeight > maxHeight)
{
resizeWidth = (uint)(maxHeight / originalAspect);
resizeHeight = maxHeight;
}
else
{
resizeWidth = originalWidth;
resizeHeight = originalHeight;
}
//Debug.WriteLine("Resizing image to: " + resizeWidth + "w/" + resizeHeight + "h/" + originalAspect + "a");
//Resize image
UIGraphics.BeginImageContext(new SizeF(resizeWidth, resizeHeight));
originalImage.Draw(new RectangleF(0, 0, resizeWidth, resizeHeight));
UIImage resizeImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
//Convert stream
Stream resizeStream = resizeImage.AsPNG().AsStream();
//Dispose resources
imageStream.Dispose();
imageNsData.Dispose();
originalImage.Dispose();
resizeImage.Dispose();
//Return stream
return(resizeStream);
}
catch (Exception ex)
{
Debug.WriteLine("Failed to download and resize image: " + ex.Message);
return(null);
}
}
