Reordering Arrays..Bitmap Data?

Here's the deal...

I read in a .bmp file and parse the headers. I find the height, width, and bitcount not to mention where the header ends. Afterwards, I load the bitmap image data into a byte array. Now all I need to do is to flip the array so that the image data is in proper order. OK...here goes....

First I did this....

Open CurrFile For Binary As ff
Get ff, HeaderSize + 1, CharInput
Close #ff
z = 0
For a = UBound(CharInput) To 0 Step -1
PicArray(z) = CharInput(a)
z = z + 1
Next

This successfully flips the image data vertically but not horizontally. I did many more complicated routines and have been able to flip it properly, but here is my REAL PROBLEM....

Using the code above 2 out of three images come out flawlessly(minus the required horizontal flip). The third image still needs the horizontal flip but is askew as well. It is actually diagonal.

I preview the images with this code....

z = 0
For a = 0 To bHeight - 1
For b = 0 To bWidth - 1
.picPreview.PSet (b, a), RGB(PicArray(z), PicArray(z + 1), PicArray(z + 2))
z = z + bBitCount
Next
Next

The 2 successful image stats:
Image 1 : 100x100@24bit
Image 2 : 512x256@24bit

The problem image stats:
Image 3 : 819x529@24bit

I'm confused. Need more info or can help let me know..

C