Originally posted a B4J/inline Java version of this in the B4J Code Snippets [//www.b4x.com/android/forum/t...byte-array-with-resize-quality-options.91746/]. @Erel pointed out though that the XUI library had the functionality that I was doing with Java, so I decided to rewrite the routine. This routine uses 100% B4X basic syntax, no inline Java, not even any

If conditionals. Unlike the Java version, this version does not throw any exceptions [on purpose], but instead returns an empty byte array if it finds/encounters any issues [which are Log[]'ed].

' 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
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

Example

Dim bImage As Image
bImage.Initialize[File.DirAssets, "b.png"]
Dim c[] As Byte = XUIImageToJPEGByteArray[bImage, -50, 0, 50]
'//www.b4x.com/android/forum/threads/b4x-bytes-to-file.70111/
# content
BytesToFile[File.DirApp, "b.jpg", c]

Resource used: Dim bImage As Image bImage.Initialize[File.DirAssets, "b.png"] Dim c[] As Byte = ImageToJPEGByteArray[bImage, -50, 0, 50] '//www.b4x.com/android/forum/threads/b4x-bytes-to-file.70111/

content BytesToFile[File.DirApp, "b.jpg", c]

Last edited: Apr 11, 2018

• 2

I try it out and if i compile it with B4J then i run into an Error:

B4J Version: 6.01
Parsing code.    [0.00s]
Compiling code.    [0.16s]
ObfuscatorMap.txt file created in Objects folder.
Compiling layouts code.    [0.00s]
Organizing libraries.    [0.00s]
Compiling generated Java code.    Error
B4J line: 51
Dim image As B4XBitmap = aImage
javac 1.8.0_151
src\b4j\example\main.java:137: error: package android.graphics does not exist
_image.setObject[[android.graphics.Bitmap][_aimage]];
                                  ^
1 error

Attached is the project, maybe i missed something.

• Image to JPEG.zip 2.8 KB · Views: 536

• 3

  _image.setObject[[android.graphics.Bitmap][_aimage]];

I've just opened your project and it complained about the missing xui library. That should not happen in B4J 6.01, since it has a version of the XUI library included, it's called jXUI. Looks like your using the Android version of the XUI library instead of B4J's internal XUI library [jXUI].

BTW: Thanks for including a test project. That gave me the clue as to what is going on.

Last edited: May 2, 2018

• 4

ahh ok, did not know that this is already present at B4J. Thanks.

• 5

May I know which Library is to be used for the type Image in the code "Dim bImage As Image"

Dim bImage As Image
bImage.Initialize[File.DirAssets, "b.png"]
Dim c[] As Byte = XUIImageToJPEGByteArray[bImage, -50, 0, 50]
'//www.b4x.com/android/forum/threads/b4x-bytes-to-file.70111/
# content
BytesToFile[File.DirApp, "b.jpg", c]

• 6

This code only works in B4J. I guess the code is NOT useable as B4X [B4A, B4J and B4i]. The Docs of this Object are pointing out that it is part of the jfx Library which is a B4j Library.

• 7

Replace:

Dim bImage As Image
bImage.Initialize[File.DirAssets, "b.png"]
Dim c[] As Byte = XUIImageToJPEGByteArray[bImage, -50, 0, 50]
'//www.b4x.com/android/forum/threads/b4x-bytes-to-file.70111/
# content
BytesToFile[File.DirApp, "b.jpg", c]

By:

Dim bImage As B4XBitmap
bImage = xui.LoadBitmap[File.DirAssets, "b.png"]
Dim c[] As Byte = XUIImageToJPEGByteArray[bImage, -50, 0, 50]
'//www.b4x.com/android/forum/threads/b4x-bytes-to-file.70111/
# content
BytesToFile[xui.DefaultFoler, "b.jpg", c]

And it becomes XUI.

• 8

Dim bImage As B4XBitmap
bImage = xui.LoadBitmap[File.DirAssets, "b.png"]
Dim c[] As Byte = XUIImageToJPEGByteArray[bImage, -50, 0, 50]
BytesToFile[File.DirDefaultExternal, "b.jpg", c]

The file created using BytesToFile[File.DirDefaultExternal, "b.jpg", c] is corrupted. Any idea why is it so. ?

I pick a file from Gallery, then resize and write it to File.DirDefaultExternal, unfortunately the file written is corrupted Here is the code that I use

Sub Process_Globals
    'These global variables will be declared once when the application starts.
    'These variables can be accessed from all modules.
    Private cc As ContentChooser
End Sub
Sub Activity_Create[FirstTime As Boolean]
    'Do not forget to load the layout file created with the visual designer. For example:
    Activity.LoadLayout["Profile"]
    If FirstTime Then
        cc.Initialize["cc"]
    End If
End Sub
Sub LblFromGallery_Click
    cc.Show["image/*", "Choose image"]
End Sub
Sub cc_Result [Success As Boolean, Dir As String, FileName As String]
    Dim realPath As String = GetPathFromContentResult[FileName]
    Dim xIV As B4XView = ivProfilePic 'ivProfilePic is an ImageView
    Dim bImage As B4XBitmap
    Dim myXui As XUI
    bImage = myXui.LoadBitmap[Dir, FileName]
    Dim c[] As Byte = XUIImageToJPEGByteArray[bImage, -50, 0, 50]
    'When I physicall check this file on File.DirDefaultExternal, it is corrupted
    BytesToFile[File.DirDefaultExternal, "MyProfilePic.jpg", c]
    xIV.SetBitmap[ LoadBitmapResize[File.DirDefaultExternal, "MyProfilePic.jpg", 332dip, 232dip, True ]]
End Sub
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
Sub FileToBytes [Dir As String, FileName As String] As Byte[]
    Return Bit.InputStreamToBytes[File.OpenInput[Dir, FileName]]
End Sub

Later I use the FileToBytes to read the image file and then write the image to a BLOB column in MySQL

Dim c[] As Byte = FileToBytes[File.DirDefaultExternal, "MyProfilePic.jpg"]

Last edited: Sep 8, 2018

• 9

If you upload your project, or at least enough of your project that replicates this issue, I’ll take a look at it

• 10

Your Code is working fine. It was my mistake. Sorry for the confusion.

• 11

I use this in a Non-Ui Project, on my local machine, it works good, but on my server [ubuntu] i have this error: