Bug: In GStreamer Gear_VideoSource: URL-based video has wrong size

[sofian]

When trying to playback the example video stream from the GStreamer tutorials the image is offset.

What is strange is that GST_BUFFER_SIZE(buffer) doesn't match buffer caps values of height / width.
Here's the info:

Buffer size: 1230720
Number of pixels (buf. size / 3): 410240
Expected number of pixels: 409920
Difference: 320 pixels

Output of buffer caps structure:
video/x-raw-rgb, width=(int)854, height=(int)480, framerate=(fraction)25/1, pixel-aspect-ratio=(fraction)1/1, interlaced=(boolean)false, bpp=(int)24, depth=(int)24, endianness=(int)4321, red_mask=(int)16711680, green_mask=(int)65280, blue_mask=(int)255;