Multimedia files written over WAN are getting truncated
- by Dean
I use the windows Multimedia API to create .wav files.
1. Open file with mmsioOpen
2. Creates WAVE,frm and data chunks using mmioCreateChunk
3. Write audio data using mmioWrite
4. Ascend out of the chunks using mmioAscend
5. Close file using mmioClose
The file is being written into a temporary location, so after it has been closed it gets copied to another location using the CopyFile.
This program is written in C++ and works great until the file it is writing resides over a WAN in a different city or country. The end result is a wav file that should be 20-30 seconds long ends up being 4 secodns long. It is always the last bit that is missing, so when you play it back it just stops before then of the recording.
I initially thought that maybe I was copying the file too soon so as a test I put in a pause of 30 seconds after closing the file using Sleep(30000), but this made no difference to either it being truncated or by how much.
I have modified the program to write to a file in parrallel using CreateFile and WriteFile, and the result is the same, so it is not an issue specifically with the mmio API's.
Does anyone have any ideas why this is happening and if there is a work-around to it?
I suspect that I may end up having the temporary location on the local drive, but this is quite a big change to the application as well as existing deployments.
thanks for everyones time
Dean
