Maybe you can use of the following routines as a startingpoint
[CODE lang="b4x" title="Image routines"]
#Region ImageRoutines
Public Sub BytesToFile (Dir As String, FileName As String, Data() As Byte)
Dim out As OutputStream = File.OpenOutput(Dir, FileName, False)
out.WriteBytes(Data, 0, Data.Length)
out.Close
End Sub
Public Sub FileToBytes (Dir As String, FileName As String) As Byte()
Return Bit.InputStreamToBytes(File.OpenInput(Dir, FileName))
End Sub
' Converts image to JPEG byte array. Ability to resize and adjust JPEG quality.
' Negative width and height values = %, such that -50 = 50% and -200 = 200%
' Positive width and height values = pixel dimensions
' If one value (either width or height) are 0, then the other value is proportionally
' calculated from the first.
' If both width and height are 0 or -100, no resizing takes place
' If quality = -1, use default quality of 75
' Will return a zero length byte array if something is wrong with the parameters
Public Sub XUIImageToJPEGByteArray(aImage As Object, width As Int, height As Int, quality As Int) As Byte()
'Sanity check quality
If (quality < -1 And quality > 100) Then
Log("Parameter quality not in range (-1..100)")
Return Array As Byte ()
End If
If quality = -1 Then quality = 75
'Sanity check incoming image
Try
Dim image As B4XBitmap = aImage
Catch
Log(LastException)
Return Array As Byte ()
End Try
'Sanity check incoming image dimensions
Dim oldWidth As Int = image.Width
Dim oldHeight As Int = image.Height
If (oldWidth = 0 And oldHeight = 0 ) Then
Log("Source image with incorrect dimensions")
Return Array As Byte ()
End If
'See if were resizing the image
Dim resize As Boolean = True
If ((width = 0 And height = 0) Or (width = -100 Or height = -100)) Then resize = False
'Resize if necessary
If (resize) Then
Dim newWidth As Int = width
Dim newHeight As Int = height
'Calculate new dimensions
If (newWidth < 0) Then newWidth = -1 * oldWidth * newWidth / 100
If (newHeight < 0) Then newHeight = -1 * oldHeight * newHeight / 100
If (newWidth = 0) Then newWidth = oldWidth * newHeight / oldHeight
If (newHeight = 0 ) Then newHeight = oldHeight * newWidth / oldWidth
image = image.Resize(newWidth, newHeight, False)
End If
'Convert image to JPEG byte array
Dim out As OutputStream
out.InitializeToBytesArray(0)
image.WriteToStream(out, quality, "JPEG")
out.Close
'Done
Return out.ToBytesArray
End Sub
#IF B4J
Public Sub WriteBase64Image(img As Image)
Dim su As StringUtils
Dim out As OutputStream
out.InitializeToBytesArray( 0 )
img.WriteToStream( out )
Dim encoded As String = su.EncodeBase64( out.ToBytesArray )
File.WriteString( File.DirApp, "base64Image.txt", encoded ) ' <- creates a textFile
Log ( encoded ) '<- show the actual encoded text
out.Close
End Sub
#END IF
#IF B4A
Public Sub WriteBase64Image(Path As String, img As Bitmap, Quality As Int, Format As String)
Dim su As StringUtils
Dim out As OutputStream
out.InitializeToBytesArray( 0 )
img.WriteToStream(out, Quality, Format )
Dim encoded As String = su.EncodeBase64( out.ToBytesArray )
File.WriteString(Path, "base64Image.txt", encoded ) ' <- creates a textFile
Log ( encoded ) '<- show the actual encoded text
out.Close
End Sub
#END IF
Public Sub XuiImageToBytes(Image As B4XBitmap) As Byte()
Dim out As OutputStream
out.InitializeToBytesArray(0)
Image.WriteToStream(out, 100, "JPEG")
out.Close
Return out.ToBytesArray
End Sub
Public Sub BytesToImage(bytes() As Byte) As B4XBitmap
Dim In As InputStream
In.InitializeFromBytesArray(bytes, 0, bytes.Length)
#if B4A or B4i
Dim bmp As Bitmap
bmp.Initialize2(In)
#else
Dim bmp As Image
bmp.Initialize2(In)
#end if
Return bmp
End Sub
' Needs JavaObject library
#IF B4J
Public Sub SaveImage(img As Image, out As OutputStream)
#ELSE IF B4A
Public Sub SaveImage(img As Bitmap, out As OutputStream)
#END IF
Dim jo As JavaObject = Me
Dim dpi As Float = 96
jo.RunMethod("saveImage", Array(out,img, dpi))
out.Close
End Sub
Sub FitImageToView(bmp As B4XBitmap, ImageView As B4XView)
Dim scale As Float = 1
#if B4i
scale = GetDeviceLayoutValues.NonnormalizedScale
#End If
ImageView.SetBitmap(bmp.Resize(ImageView.Width * scale, ImageView.Height * scale, True))
End Sub
Public Sub FillImageToView(bmp As B4XBitmap, ImageView As B4XView)
Dim bmpRatio As Float = bmp.Width / bmp.Height
Dim viewRatio As Float = ImageView.Width / ImageView.Height
If viewRatio > bmpRatio Then
Dim NewHeight As Int = bmp.Width / viewRatio
bmp = bmp.Crop(0, bmp.Height / 2 - NewHeight / 2, bmp.Width, NewHeight)
Else if viewRatio < bmpRatio Then
Dim NewWidth As Int = bmp.Height * viewRatio
bmp = bmp.Crop(bmp.Width / 2 - NewWidth / 2, 0, NewWidth, bmp.Height)
End If
Dim scale As Float = 1
#if B4i
scale = GetDeviceLayoutValues.NonnormalizedScale
#End If
ImageView.SetBitmap(bmp.Resize(ImageView.Width * scale, ImageView.Height * scale, True))
End Sub
Sub FileToBase64 (Dir As String, FileName As String) As String
Dim su As StringUtils
If Dir = "" Or FileName = "" Then Return ""
Return su.EncodeBase64(Bit.InputStreamToBytes(File.OpenInput(Dir, FileName)))
End Sub
#IF B4J
Public Sub FileToBase64String
Private fc As FileChooser
fc.Initialize
fc.Title="Browse and select a file"
fc.SetExtensionFilter("Image", Array As String ("*.jpg", "*.png", "*.gif"))
fc.InitialFileName = ""
Private FileName As String = fc.ShowOpen(MainForm) 'this is the FileChooser
NewPath = File.GetFileParent(FileName)
NewFile = File.GetName(FileName)
' Private Base64String As TextField
Base64Text.Text = FileToBase64(NewPath, NewFile)
Dim bmp As B4XBitmap = xui.LoadBitmap(NewPath, NewFile)
FitImageToView(bmp, ImageView1)
End Sub
#END IF
#End Region ' --- ImageRoutines[/CODE]
