Picture to Array, Array to Picture

[jtballer4]

OK I AM GETTING SO ANNOYED OVER THIS PROBLEM, ALL I WANT TO DO IS SEND A JPG OVER WINSOCK AND I CANT FIGURE OUT HOW TO DO IT

I know I have to change the picture into a byte array to send it and then change it back, BUT WHAT IS THE CODE FOR THIS????

I've been posting on these messageboards for 4 days with no Good response to this answer, Does anyone know the code or function to do this

Thanks,
Justin

[Sastraxi]

To make it easy on yourself, I would simply send 'packets'. Send 1024 bytes at a time, by appending the characters to each other in a STRING (ex. String = Chr(0) & Chr(1) & Chr(2), but programatically). Next, use Winsock1.Send String, vbString (I've don't use winsock that often so it might not need the vbString). Then, on the other side, when you get the packets, start writing them to a file.

[Jotaf98]

Huh and what would happen when you encontered a null character, hmm?

You just get a byte array from the image and send it, there's a function for that. I already gave you the code... ok, here it is, just copy and paste:

Declarations:
 
Private Type SAFEARRAYBOUND
    cElements As Long
    lLbound As Long
End Type
 
Private Type SAFEARRAY1D
    cDims As Integer
    fFeatures As Integer
    cbElements As Long
    cLocks As Long
    pvData As Long
    Bounds(0 To 0) As SAFEARRAYBOUND
End Type
 
Private Type SAFEARRAY2D
    cDims As Integer
    fFeatures As Integer
    cbElements As Long
    cLocks As Long
    pvData As Long
    Bounds(0 To 1) As SAFEARRAYBOUND
End Type
 
Private Declare Function VarPtrArray Lib "msvbvm50.dll" Alias "VarPtr" (Ptr() As Any) As Long
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (pDst As Any, pSrc As Any, ByVal ByteLen As Long)
Private Type BITMAP
    bmType As Long
    bmWidth As Long
    bmHeight As Long
    bmWidthBytes As Long
    bmPlanes As Integer
    bmBitsPixel As Integer
    bmBits As Long
End Type
 
Private Declare Function BitBlt Lib "gdi32" (ByVal hDestDC As Long, ByVal X As Long, ByVal Y As Long, ByVal nWidth As Long, ByVal nHeight As Long, ByVal hSrcDC As Long, ByVal xSrc As Long, ByVal ySrc As Long, ByVal dwRop As Long) As Long
Private Const SRCCOPY = &HCC0020 ' (DWORD) dest = source
 
Private Declare Function GetObjectAPI Lib "gdi32" Alias "GetObjectA" (ByVal hObject As Long, ByVal nCount As Long, lpObject As Any) As Long
 
 
 
'To get an array from the image:
 
' these are used to address the pixel using matrices
Dim pict() As Byte
 
Dim sa As SAFEARRAY2D, bmp As BITMAP
' get bitmap info
GetObjectAPI Pictbox.Picture, Len(bmp), bmp
' exit if not a supported bitmap
If bmp.bmBitsPixel <> 24 Then
    MsgBox " 24-bit bitmaps only", vbCritical
    Exit Sub
End If
   
' have the local matrix point to bitmap pixels
With sa
    .cbElements = 1
    .cDims = 2
    .Bounds(0).lLbound = 0
    .Bounds(0).cElements = bmp.bmHeight
    .Bounds(1).lLbound = 0
    .Bounds(1).cElements = bmp.bmWidthBytes
    .pvData = bmp.bmBits
End With
CopyMemory ByVal VarPtrArray(pict), VarPtr(sa), 4
 
 
 
'To put it back and clean up:
 
' clear the temporary array descriptor
' without destroying the local temporary array
CopyMemory ByVal VarPtrArray(pict), 0&, 4

Hope that helps

[Sastraxi]

So, you're telling him to send an uncompressed bitmap?

[Jotaf98]

you're right Sas

Ok, why don't you forget all that code, and just load the file as binary to a byte array, then send it like that? The other program would just create a file with that array and load it as a JPG

[jtballer4]

Thanks

[Jotaf98]

No problem
Thanks Sas

[Sastraxi]

Your way would've worked well for LAN situations.

[Jotaf98]

Yes, you're right, but usually Winsock is used for internet connections... (writing and reading the file would have taken much longer, right?)

[Cloral]

I have a question regarding GetObjectAPI. Can you use it on any StdPicture object to get the image data? Also, is there a way to do it in reverse - i.e. a SetObjectAPI function? That would be quite useful to me.

Also, could these methods be used on a D3D texture object, or is there another method that one has to use?

[Sastraxi]

You can use SelectObject, I believe.

[Electroman]

I think I should point this out that in the code given above by Jotaf98 he's missed off this line,as most example of this method do:

Private Declare Function VarPtr Lib "msvbvm50.dll" (Ptr As Any) As Long

[Sastraxi]

VarPtr is standard VB syntax. VarPtrArray isn't.

[CornedBee]

Using SAFEARRAY in VB, it's paradox...

[Electroman]

Saxtraxi i'm not saying replace the API with the one I gave, I'm saying you need it aswel because in the following line its called twice, one passes an array and one passes a non-array

CopyMemory ByVal VarPtrArray(pict), VarPtr(sa), 4

It thro's up errors without the "VarPtr" being declared.