Export animation to Collada - output only key frames without interpolated ones

[Anonymous]

I created skeleton in Maya 2015 and animated it - created 2 key frames for non-looped walking cycle: 1 key for the right step (at frame 1) and 1 key for the left step (at frame 15). I have default 24 frames per second as "Time" setting. Animation plays fine in Maya - begins at the right step and ends at the left one.

The problem appears when I export my scene to Collada format (DAE_FBX export). Exported .dae file contains all 15 frames of animation for each joint. I. e. each <animation> node (for each joint) describes 15 matrices - not only for the first and the last key frames that I created, but also 13 interpolated ones as well. And I see no element in Collada file that would give me information about 2 key frames that were set in Maya, so I could avoid interpolated ones. But I need only those 2 key frames as I may generate the frames in-between by myself. Is there any setting or something to reach that? At this case I know that I have only 2 actual key frames - the first and the last one, but later when I have to create and export more complex animations, I won't be able to identify manually created key frames among 10's or 100's of auto-generated ones.

I tried enabling/disabling different settings in export "Options..." section, but none of them helped to remove unnecessary key frames in output file. I tried "Bake animation" as well, but even when it is disabled, seems like the exporter still generate the in-between frames, which he shouldn't, as far as I can tell. I exported animations from Blender, and got only key frames without interpolated ones. Do I miss some setting or it is Maya's feature? How can I get only manually created key frames in output .dae file?

Big thanks in advance for any help!