Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

Mp3 decoder too slow on NiosII

Hi,all I'm now designing a mp3 player for DE2 board, which use libmad for mp3 decoding. But currently, the speed is too slow for real time playing. The core is NiosII fastest core,i cache=8kb, ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

I have tried -O2 and -O3, but the same problem occurs which is the program don't enter the decoding progress. I use an external interrupt to set a begin decoding flag and poll this flag in the main function. When using -O2 or -O3, the beginning flag is set correctly, but the polling didn't work. If I set a breakpoint there, the program shall never go to that part of the main function. I don't know what does optimization really do under different level. Can you give some idea about it?