It seems as if more size is being allocated to the texture then is needed. So when the DirectShow graph is transfered to the texture, there is extra space on the bottom.
Looking at the sizes of the pitches, this suspicion is confirmed. Once the video gets to a certain width or height, it seems a predefined width or height is selected for it, defined by the minimum number of bits needed to hold that size. e.g. If i have a 128x128 video, i'm fine, because 128 goes into 7-bits perfectly. If i have a 352x240 video, however, the closest values are 512 (9-bits) and 256 (8-bits). So my texture size is 512x256 even though my video is only 352x240.
is there a way to either A) make sure my DirectX object texture is really 352x240
or B) apply a filter to the DirectShow video to resize it to 512x256 before it is applied as a texture