B4J Question BMP Image To Byte Array

[nazilabdulla]

How to read / write bytes from/to B4XBitmap ?
Image can be processed by this method ?
Is it best solution for image recognition ? Any other better way ?

 

[kimstudio]

Check BitmapCreator and its examples for pixel access and image processing.

 

[xulihang]

Public Sub ImageToBytes(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 Image
    Dim In As InputStream
    In.InitializeFromBytesArray(bytes, 0, bytes.Length)
    Dim bmp As Image
    bmp.Initialize2(In)
    In.Close
    Return bmp
End Sub

 

[Mahares]

@xulihang: Why are you taking credit for these tools when they were made by Erel in this link in 2018. How are they different. Maybe you mean 'Used them with B4J'?

[B4X] Bytes To File

This code is no longer needed. Use File.WriteBytes / ReadBytes. Write an array of bytes to a file and read a file into an array of bytes. Sub BytesToFile (Dir As String, FileName As String, Data() As Byte) Dim out As OutputStream = File.OpenOutput(Dir, FileName, False)...

www.b4x.com

 

[Daestrum]

@Mahares I think you are reading their footer, the tools they made are below.

 

[TILogistic]

Is it best solution for image recognition ? Any other better way ?

Search forum

find Area in Image

Hello, im searching for a solution to find a given Area in an Image. I want to make screenshots and simulate Mousclicks on specific areas when something is found. the Area bitmap is fix in my assets, and i need the coordinates where this little Area image is shown in the screenshot. this area...

www.b4x.com

 

[kimstudio]

Image.WriteToStream(out, 100, "JPEG")

"JPEG" means the output bytestream is jpg compressed? then it would be hard for following image processing.

 

[xulihang]

"JPEG" means the output bytestream is jpg compressed? then it would be hard for following image processing.

It works okay in my case for OCR.