/// <summary>
/// Read image files, covert the data and save it to the native pointer
/// </summary>
/// <typeparam name="T">The type of the data to covert the image pixel values to. e.g. "float" or "byte"</typeparam>
/// <param name="fileNames">The name of the image files</param>
/// <param name="inputHeight">The height of the image, must match the height requirement for the tensor</param>
/// <param name="inputWidth">The width of the image, must match the width requirement for the tensor</param>
/// <param name="inputMean">The mean value, it will be subtracted from the input image pixel values</param>
/// <param name="scale">The scale, after mean is subtracted, the scale will be used to multiply the pixel values</param>
/// <param name="flipUpSideDown">If true, the image needs to be flipped up side down</param>
/// <param name="swapBR">If true, will flip the Blue channel with the Red. e.g. If false, the tensor's color channel order will be RGB. If true, the tensor's color channle order will be BGR </param>
/// <param name="status">Tensorflow status</param>
/// <returns>The tensor that contains all the image files</returns>
private static Tensor NativeReadTensorFromImageFiles <T>(
String[] fileNames,
int inputHeight = -1,
int inputWidth = -1,
float inputMean = 0.0f,
float scale = 1.0f,
bool flipUpSideDown = false,
bool swapBR = false,
Status status = null) where T : struct
{
if (fileNames.Length == 0)
{
throw new ArgumentException("Intput file names do not contain any files");
}
String fileName = fileNames[0];
if (!File.Exists(fileName))
{
throw new FileNotFoundException(String.Format("File {0} do not exist.", fileName));
}
IntPtr dataPtr;
int step;
Tensor t;
#if __ANDROID__
using (BitmapFactory.Options options = new BitmapFactory.Options())
{
options.InPreferredConfig = Android.Graphics.Bitmap.Config.Argb8888; //Prefer ARGB8888 format
using (Android.Graphics.Bitmap bmp0 = Android.Graphics.BitmapFactory.DecodeFile(fileName, options))
{
if (inputHeight <= 0)
{
inputHeight = bmp0.Height;
}
if (inputWidth <= 0)
{
inputWidth = bmp0.Width;
}
if (typeof(T) == typeof(float))
{
t = new Tensor(DataType.Float,
new int[] { fileNames.Length, (int)inputHeight, (int)inputWidth, 3 });
}
else if (typeof(T) == typeof(byte))
{
t = new Tensor(DataType.Uint8,
new int[] { fileNames.Length, (int)inputHeight, (int)inputWidth, 3 });
}
else
{
throw new Exception(String.Format("Conversion to tensor of type {0} is not implemented",
typeof(T)));
}
dataPtr = t.DataPointer;
step = NativeImageIO.ReadBitmapToTensor <T>(
bmp0,
dataPtr,
inputHeight,
inputWidth,
inputMean,
scale,
flipUpSideDown,
swapBR);
dataPtr = new IntPtr(dataPtr.ToInt64() + step);
}
for (int i = 1; i < fileNames.Length; i++)
{
fileName = fileNames[i];
if (!File.Exists(fileName))
{
throw new FileNotFoundException(String.Format("File {0} do not exist.", fileName));
}
//Read the file using Bitmap class
using (Android.Graphics.Bitmap bmp = Android.Graphics.BitmapFactory.DecodeFile(fileName, options))
{
step = NativeImageIO.ReadBitmapToTensor <T>(
bmp,
dataPtr,
inputHeight,
inputWidth,
inputMean,
scale,
flipUpSideDown,
swapBR);
dataPtr = new IntPtr(dataPtr.ToInt64() + step);
}
}
}
#elif __MACOS__
using (NSImage image0 = new NSImage(fileName))
{
if (inputHeight <= 0)
{
inputHeight = (int)image0.Size.Height;
}
if (inputWidth <= 0)
{
inputWidth = (int)image0.Size.Width;
}
if (typeof(T) == typeof(float))
{
t = new Tensor(DataType.Float,
new int[] { fileNames.Length, (int)inputHeight, (int)inputWidth, 3 });
}
else if (typeof(T) == typeof(byte))
{
t = new Tensor(DataType.Uint8,
new int[] { fileNames.Length, (int)inputHeight, (int)inputWidth, 3 });
}
else
{
throw new Exception(String.Format("Conversion to tensor of type {0} is not implemented",
typeof(T)));
}
dataPtr = t.DataPointer;
step = NativeImageIO.ReadImageToTensor <T>(
image0, dataPtr, inputHeight, inputWidth, inputMean, scale,
flipUpSideDown, swapBR);
dataPtr = new IntPtr(dataPtr.ToInt64() + step);
}
for (int i = 1; i < fileNames.Length; i++)
{
fileName = fileNames[i];
if (!File.Exists(fileName))
{
throw new FileNotFoundException(String.Format("File {0} do not exist.", fileName));
}
//Read the file using Bitmap class
using (NSImage image = new NSImage(fileName))
{
step = NativeImageIO.ReadImageToTensor <T>(image, dataPtr, inputHeight, inputWidth, inputMean, scale,
flipUpSideDown, swapBR);
dataPtr = new IntPtr(dataPtr.ToInt64() + step);
}
}
#else
using (System.Drawing.Bitmap bmp0 = new System.Drawing.Bitmap(fileName))
{
if (inputHeight <= 0)
{
inputHeight = bmp0.Height;
}
if (inputWidth <= 0)
{
inputWidth = bmp0.Width;
}
if (typeof(T) == typeof(float))
{
t = new Tensor(DataType.Float,
new int[] { fileNames.Length, (int)inputHeight, (int)inputWidth, 3 });
}
else if (typeof(T) == typeof(byte))
{
t = new Tensor(DataType.Uint8,
new int[] { fileNames.Length, (int)inputHeight, (int)inputWidth, 3 });
}
else
{
throw new Exception(String.Format("Conversion to tensor of type {0} is not implemented",
typeof(T)));
}
dataPtr = t.DataPointer;
step = NativeImageIO.ReadBitmapToTensor <T>(bmp0, dataPtr, inputHeight, inputWidth, inputMean, scale,
flipUpSideDown, swapBR);
dataPtr = new IntPtr(dataPtr.ToInt64() + step);
}
for (int i = 1; i < fileNames.Length; i++)
{
fileName = fileNames[i];
if (!File.Exists(fileName))
{
throw new FileNotFoundException(String.Format("File {0} do not exist.", fileName));
}
//Read the file using Bitmap class
using (System.Drawing.Bitmap bmp = new System.Drawing.Bitmap(fileName))
{
step = NativeImageIO.ReadBitmapToTensor <T>(bmp, dataPtr, inputHeight, inputWidth, inputMean, scale,
flipUpSideDown, swapBR);
dataPtr = new IntPtr(dataPtr.ToInt64() + step);
}
}
#endif
return(t);
}