Displaying images with OLE functions

[Vortex]

As a continuation to the OleLoadPicturePath thread, I created a static library to display images based on the usage of OLE functions.

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LoadImageFromFile PROC pImageFileName:DWORD

This function loads a BMP, JPG, GIF or WMF image from disc and returns a handle to the image.

pImageFileName is a pointer to the FULL path name of the image file to be displayed

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LoadImageFromMem PROC pImageAddr:DWORD,ImageLen:DWORD

This function returns the handle of an image stored in memory. Valid image formats are BMP, JPG, GIF and WMF

pImageAddr is a pointer to the location of the image in memory.

ImageLen is the size of the image.

In case of error, both of the functions will return NULL.

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LoadImageFromFile PROC pImageFileName:DWORD

LOCAL hHeap:DWORD
LOCAL pMem:DWORD
LOCAL hOLEimg:DWORD
LOCAL hBitmap:DWORD
LOCAL pPicture:DWORD

    mov     hBitmap,0
    mov     pPicture,0
   
    invoke  GetProcessHeap
    test    eax,eax
    jz      _exit
   
    mov     hHeap,eax
    invoke  HeapAlloc,eax,HEAP_ZERO_MEMORY,2*MAX_PATH
    test    eax,eax
    jz      _exit
   
    mov     pMem,eax
    invoke  MultiByteToWideChar,CP_ACP,NULL,pImageFileName,-1,eax,2*MAX_PATH
    test    eax,eax
    jz      FreeMem
   
    invoke  OleLoadPicturePath,pMem,0,0,0,ADDR IID_IPicture,ADDR pPicture
    test    eax,eax
    jnz     FreeMem

    lea     eax,hOLEimg
    push    eax
    mov     eax,pPicture
    push    eax
    mov     eax,DWORD PTR [eax]
    call    IPicture.get_Handle[eax]
    test    eax,eax
    jnz     ReleasePict

    invoke  CopyImage,hOLEimg,IMAGE_BITMAP,0,0,LR_COPYRETURNORG
    test    eax,eax
    jz      ReleasePict
    mov     hBitmap,eax

ReleasePict:

    mov     eax,pPicture
    push    eax
    mov     eax,DWORD PTR [eax]
    call    IPicture.Release[eax]

FreeMem:

    invoke  HeapFree,hHeap,0,pMem
   
_exit:

    mov     eax,hBitmap
    ret

LoadImageFromFile ENDP


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LoadImageFromMem PROC USES esi edi pImageAddr:DWORD,ImageLen:DWORD

LOCAL hOLEimg:DWORD
LOCAL hBitmap:DWORD
LOCAL pPicture:DWORD
LOCAL pStream:DWORD
LOCAL hGlobal:DWORD

    mov     hBitmap,0
    mov     pStream,0
    mov     pPicture,0

    invoke  GlobalAlloc,GMEM_MOVEABLE or GMEM_NODISCARD,ImageLen
    mov     hGlobal,eax
    invoke  GlobalLock,eax

    cld
    mov     esi,pImageAddr
    mov     edi,eax
    mov     ecx,ImageLen
    shr     ecx,2
    rep     movsd

    mov     ecx,ImageLen
    and     ecx,3
    rep     movsb

    invoke  CreateStreamOnHGlobal,hGlobal,TRUE,ADDR pStream
    test    eax,eax
    jnz     _exit

    invoke  OleLoadPicture,pStream,0,FALSE,ADDR IID_IPicture,ADDR pPicture
    test    eax,eax
    jnz     ReleaseStream

    lea     eax,hOLEimg
    push    eax
    mov     eax,pPicture
    push    eax
    mov     eax,DWORD PTR [eax]
    call    IPicture.get_Handle[eax]
    test    eax,eax
    jnz     ReleasePict

    invoke  CopyImage,hOLEimg,IMAGE_BITMAP,0,0,LR_COPYRETURNORG
    test    eax,eax
    jz      ReleasePict
    mov     hBitmap,eax

ReleasePict:

    mov     eax,pPicture
    push    eax
    mov     eax,DWORD PTR [eax]
    call    IPicture.Release[eax]

ReleaseStream:

    mov     eax,pStream
    push    eax
    mov     eax,DWORD PTR [eax]
    call    IStream.IUnknown.Release[eax]

_exit:

    mov     eax,hBitmap
    ret   

LoadImageFromMem ENDP



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[PBrennick]

Thank you,very nice as always.

Paul

[Vortex]

- Precaution against memory allocation failure : LoadImageFromMem checks if GlobalAlloc fails or not.

Code Select Expand

    invoke  GlobalAlloc,GMEM_MOVEABLE or GMEM_NODISCARD,ImageLen
    test    eax,eax
    jz      _exit
    mov     hGlobal,eax
    invoke  GlobalLock,eax
    test    eax,eax
    jz      _exit
.
.
.
    invoke  CreateStreamOnHGlobal,hGlobal,TRUE,ADDR pStream
    test    eax,eax
    jz      @f
    invoke  GlobalUnlock,hGlobal
    invoke  GlobalFree,hGlobal
    jmp     _exit
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