Creating MP4 container

[artak]

I want to write a program which will create MP4 container with H.264 video and any compliant audio (for now it will be mp3 or aac). I have created two MP4 containers containing only H.264 video (without audio) using Yamb first with 10fps and second with 25fps. I noticed what in the first one where is two chunks (6 samples in first chunk and 2 samples in second chunk) while in 2nd one with 25fps where is only one chunk containing all 8 samples.
How I now the chunks are for interleaving two or more tracks, but where is only one track. Can anybody explain me how the number of chunks connected with FPS. I would also like to now how chunks connected with progressive download. Thanks in advance.

[bond]

try muxing the same stream with mp4creator and check whether its the same

[artak]

I can't understand how it will answer to my questions.:confused:

[bond]

there might not be a relationship between chunks and fps. try mp4creator to see if it acts differently than mp4box