Could some DSP guru please clarify the following ? I have a simple audio application, in which at records time about 20000 bytes from the received audio signal. I am using PCM encoding with sampling frequency 16000, 16 bits, mono channel, little endian and signed. I wish to do FFT with the collected data. Since I collect bytes, I iterate through the buffer, collecting two bytes at a time, and with simple processing convert these byte pairs to shorts. I collect altogether 1024 shorts, by processing the first 2048 bytes of the raw data. From basic DSP principles we know that if 'N' data samples have been collected at a sampling frequency of 'fs' Hz, then the FFT resolution is: fs/N. So, in my case, is the resolution 16000/20000 or 16000/1024 ? I am confused. Please let me know.
Confusion about FFT resolution - PLEASE HELP
Started by ●April 28, 2008
Reply by ●April 28, 20082008-04-28
N = 1024 in your case... You do not care about the bytes after you assemble your audio vector... On Apr 28, 8:03 pm, "cpptutor2...@yahoo.com" <cpptutor2...@yahoo.com> wrote:> Could some DSP guru please clarify the following ? I have a simple > audio application, in which at records time about 20000 bytes from the > received audio signal. I am using PCM encoding with sampling frequency > 16000, 16 bits, mono channel, little endian and signed. > I wish to do FFT with the collected data. Since I collect bytes, I > iterate through the buffer, collecting two bytes at a time, and with > simple processing convert these byte pairs to shorts. I collect > altogether 1024 shorts, by processing the first 2048 bytes of the raw > data. > From basic DSP principles we know that if 'N' data samples have been > collected at a sampling frequency of 'fs' Hz, then the FFT resolution > is: > fs/N. > So, in my case, is the resolution 16000/20000 or 16000/1024 ? I am > confused. Please let me know.