I made a new version for importing YUV-files (WITH source code):
http://www.avisynth.org/warpenterprises/
RawSource(filename, width, height, pixeltype)
e.g.
RawSource("d:\src6_ref__625.yuv",720,576,"UYVY")
Change the framerate with AssumeFPS(30) if it is not 25fps.
"pixeltype" isn't the internal AviSynth-format, but the format in the YUV-file. This will be mapped correctly, without any resampling.
Supported types:
RGB, RGBA, BGR, BGRA, YUYV, UYVY, YVYU, VYUY
Remember, this plugin reads video files which contain many frames.
It works for reading ONE frame, but not for file sequences (they must be loaded separately).