| Message ID | 20210110100239.27588-6-vr_qemu@t-online.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | next round of audio patches | expand |
On 10/01/2021 11.02, Volker Rümelin wrote: > Fill the remaining sample buffer with silence. To fill it with > zeroes is wrong for unsigned samples because this is silence > with a DC bias. > > Signed-off-by: Volker Rümelin <vr_qemu@t-online.de> > --- > audio/sdlaudio.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/audio/sdlaudio.c b/audio/sdlaudio.c > index 79eed23849..01ae4c600e 100644 > --- a/audio/sdlaudio.c > +++ b/audio/sdlaudio.c > @@ -235,7 +235,8 @@ static void sdl_callback (void *opaque, Uint8 *buf, int len) > > /* clear remaining buffer that we couldn't fill with data */ > if (len) { > - memset(buf, 0, len); > + audio_pcm_info_clear_buf(&hw->info, buf, > + len / hw->info.bytes_per_frame); > } > } > Ignorant question: Is anybody still using unsigned samples in the 21st century? Anyway, Reviewed-by: Thomas Huth <thuth@redhat.com>
> On 10/01/2021 11.02, Volker Rümelin wrote: >> Fill the remaining sample buffer with silence. To fill it with >> zeroes is wrong for unsigned samples because this is silence >> with a DC bias. >> >> Signed-off-by: Volker Rümelin <vr_qemu@t-online.de> >> --- >> audio/sdlaudio.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/audio/sdlaudio.c b/audio/sdlaudio.c >> index 79eed23849..01ae4c600e 100644 >> --- a/audio/sdlaudio.c >> +++ b/audio/sdlaudio.c >> @@ -235,7 +235,8 @@ static void sdl_callback (void *opaque, Uint8 >> *buf, int len) >> /* clear remaining buffer that we couldn't fill with data */ >> if (len) { >> - memset(buf, 0, len); >> + audio_pcm_info_clear_buf(&hw->info, buf, >> + len / hw->info.bytes_per_frame); >> } >> } >> > > Ignorant question: Is anybody still using unsigned samples in the 21st > century? > Hi Thomas, you are probably right that no one is knowingly using unsigned samples anymore. But qemu emulates audio devices from the last century. For example with the command line options -machine pcspk-audiodev=audio0 -audiodev sdl,id=audio0,out.buffer-length=3750,out.mixing-engine=off you will see 8 bit unsigned samples in the SDL callback buffer. With best regards, Volker > Anyway, > Reviewed-by: Thomas Huth <thuth@redhat.com> >
diff --git a/audio/sdlaudio.c b/audio/sdlaudio.c index 79eed23849..01ae4c600e 100644 --- a/audio/sdlaudio.c +++ b/audio/sdlaudio.c @@ -235,7 +235,8 @@ static void sdl_callback (void *opaque, Uint8 *buf, int len) /* clear remaining buffer that we couldn't fill with data */ if (len) { - memset(buf, 0, len); + audio_pcm_info_clear_buf(&hw->info, buf, + len / hw->info.bytes_per_frame); } }
Fill the remaining sample buffer with silence. To fill it with zeroes is wrong for unsigned samples because this is silence with a DC bias. Signed-off-by: Volker Rümelin <vr_qemu@t-online.de> --- audio/sdlaudio.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)