Intel Media SDK doesn't support RGB24 content, the RGB format we support is RGB32 and the list of other supported formats is present @ https://software.intel.com/sites/default/files/mediasdk-man.pdf Pg 7. To use AVI file into Media SDK, you need a demuxer to content from the container and feed into Media SDK pipeline. You can use ffmpeg for that. Media SDK focus is on encoding/decoding/video processing. I hope that was kind of the information you were looking for, if not please let us know.
RGB32 is color format for the raw YUV. AVI container would have a bitstream, which you can demux using ffmpeg or yamb tool. There is a sample(sample_full_transcode) in the deprecated sample package present here which shows the complete pipeline. The Media SDK supported codecs are h264, mpeg2, mjpeg, hevc, vp8/vp9(limited support).
Containers cannot be directly fed into the Media SDK pipeline, they needs to demuxed. Once demuxed, if the bitstreams are from above mentioned codec, media sdk should be able to decode. Also, media SDK supports many uncompressed raw formats like YV12, NV12, RGB32, YUY2 etc mentioned in the manual. MediaPlayer, VLC are the players to render the decoded content. We do support direct show, you can find the pipeline for a directshow filter in the deprecated samples package.
Can you please let us know your use case or pipeline, so that we can explain in what regions Media SDK can be helpful. You can send the pipeline through message if you like.