can't write to QIODevice timely.

QTier

pcm’s length nbytes = 4096,nsize = 2048.
when I set periodSize = 4096 , there is a murmur.
when I set periodSize = 2048, write two times , there is noise. but when I write the first 2048 B , or the last 2048 B independently, it is clear, but I clearly feels like it is fast forwarding.

my code as fllowing:

void AudioDevice::device_out(const char* pcm,qint64 nbytes)
{
//int32_t delay = 1000000 / (double) audioOut->format().sampleRate();
int32_t nsize = audioOut->periodSize();
int32_t nleft = nbytes;
int32_t nb = 0;

while( 0 != nleft){
   if(audioOut->bytesFree() >= nsize){
        nleft = (nleft > nsize) ? nsize : nleft;
        nb   += audio_device->write(pcm + nb, nleft);
        nleft = nbytes - nb;
    }
   else av_usleep(10);
}

}

SGaist

Hi and welcome to devnet,

What are you writing to ?
What does this QIODevice represent ?
Which OS are you on ?
Which version of Qt are you using ?
What exactly are you trying to achieve ?

Christian Ehrlicher

... and please properly format your code with the code tags so others can read it.