Displaying 20 results from an estimated 4000 matches similar to: "float to PCM packing in libvorbisfile"
2002 Jan 03
3
Suggestion for libvorbisfile: scaling
I've been experimenting with the ideas of Replay Gain[1] and find that
ogg123 doesn't have a way of specifying the scaling applied to
replayed samples (like -f in mpg123).
Looking at libvorbisfile, I see no function exactly matching this
possibly desirable behaviour.
ov_read() scales by either 128 (byte output) or 32768 (word output),
but there's nothing in between.
ov_read_float()
2004 Jun 16
2
ogg123 volume?
Hi,
I need to adjust the output volume from ogg123 the same way that
mpg123 has the "-f n change scalefactor [32768]" option. I need to
do this within ogg123, instead of alternatives that involve pipes,
such as piping the output to sox.
I do not believe that this is currently possible in ogg123, and I'm
looking for some suggestions as to how it can be accomplished by
modifying
2004 Jun 16
2
ogg123 volume?
Hi,
I need to adjust the output volume from ogg123 the same way that
mpg123 has the "-f n change scalefactor [32768]" option. I need to
do this within ogg123, instead of alternatives that involve pipes,
such as piping the output to sox.
I do not believe that this is currently possible in ogg123, and I'm
looking for some suggestions as to how it can be accomplished by
modifying
2003 Feb 02
1
Observations about the floating point data in vorbisfile
Hello.
I noticed that when reading data with ov_read_float(), you can get
values outside [-1..1] when the stream is encoded at lower quality, but
with higher quality, the values trim down to inside [-1..1].
Looking at the plot from -q10, the data from ov_read_float seems
clipped.
I've made some plots of encoding the start of Rammsteins Feuer from the
xXx soundtrack (it's a pretty loud
2003 May 12
0
vorbisfile ov_pack_pcm patch
Here's a patch to vorbisfile.c in libvorbis that splits the float to integer
pcm packing out of ov_read into it's own function.
The good stuff:
- ov_pack_pcm can be used by folks who decode to float pcm with
ov_read_float to do various sound manipulations (eg, preamp, fades,
replaygain). No more need to roll your own, which will really begin to
pay off when 24 bit output gets
2002 Jan 16
2
Problem with ov_read_float()
Greetings,
I'm having some sort of problem using ov_read_float(). Everything looks
good to me, but I'm trashing memory somehow, so clearly I'm screwing
something up. What confuses me is why it takes a ***float for the
buffer.
I call it like so:
float **buffer
bytes_read = ov_read_float(&vf, &buffer, 0)
memcpy (b, *buffer, 0);
This compiles fine, but after a few reads,
2002 Jul 20
1
small mistake in docs
Hi,
in ov_read_float.html there is a small mistake:
long ov_read(OggVorbis_File *vf, float ***pcm_channels, int
*bitstream);
hould read:
long ov_read_float(OggVorbis_File *vf, float ***pcm_channels, int
samples, int *bitstream);
It seems this function has been changed (compared to the RC3). Anything
else worked fine for me with the 1.0 release.
Olaf
<p>--- >8 ----
List archives:
2005 Oct 09
1
ov_read_float vs. ov_read
Hello,
Am I missing something?
float** pcm_channels;
int bitstream;
int where = ov_pcm_tell(&vf);
-> The Result is "0";
ov_read_float(&vf, &pcm_channels, 1, &bitstream);
-> pcm_channels[0][0] is "0.000338580"
ov_pcm_seek(&vf, 0);
char* buffer = new char[2];
ov_read(&vf, buffer, sizeof(buffer), 0, 2, 1, &bitstream);
short temp =
2015 Jun 14
2
Sound glitch when using libvorbisfile and libao
Hi there,
I've been grappling with this for some time, so I'm finally breaking down
and trying this list.
I'm trying to integrate libvorbisfile and libao to create a simple sound
file player, a la ogg123. To do this, I borrowed heavily from ao_example.c
and vorbisfile_example.c. I feed the buffer from ov_read into ao_play in a
simple loop. It usually works, but occasionally all it
2011 Jul 19
0
ov_read error on macosx - SOLVED
Hi!
I solved the problem using ov_read_float instead ov_read.
Still do not know why ov_read returned garbage, but ov_read_float works
fine!
Thanks!
El 17 de julio de 2011 10:41, Juan Miguel Mart?n Mu?oz
<jmcubo at gmail.com>escribi?:
> Hi, thanks for your replies!
>
> ogg.k, I'm sure MACOSX is defined. When I'm debugging line by line the
> program runs into ov_read.
2015 Jun 27
0
Sound glitch when using libvorbisfile and libao
Hi Gunter,
I've solved the sound glitch. Since it was hard to reproduce, it took me a
while, but I eventually figured it out.
What I needed to do was fill the buffer with more data before handing it
off to ao_play. It requires lots of bookkeeping, pointer arithmetic, and a
sufficiently large buffer.
First, the bigger buffer. I just pulled this code from ogg123:
#define PRIMAGIC
2015 Jun 14
2
Sound glitch when using libvorbisfile and libao
Hi Gunter,
I think this problem started happening when I upgraded from Debian Wheezy
to Debian Jessie. If nothing looks amiss in my code, it probably is a sound
driver problem. But since it works 100% of the time in ogg123, I feel I
must have missed some corner case.
My audio driver is almost always active. I usually have my music player
going in the background when I do my testing. The problem
2004 Sep 06
1
Plain playback
Hi all,
Perhaps a stupid question, but I just need pieces of audio from a file. I
know I have to use vorbisfile, and the example compiles, but I don't know
how to read the buffer. In fact, it's not even documented (or I'm looking at
the wrong place). I assumed it was a interleaved buffer containing unsigned
shorts, but that didn't work.
I also tried the normal decode example,
2015 Jun 14
0
Sound glitch when using libvorbisfile and libao
How can this problem be reproduced? If you have an specific .ogg file
that gives problems it would be helpful to have them so we can try to
reproduce them.
Kind regards,
Gunter.
On So, Jun 14, 2015 at 7:10 , Marshall Mason <marshallmason2 at gmail.com>
wrote:
> Hi there,
> I've been grappling with this for some time, so I'm finally breaking
> down and trying this
2003 Jul 27
2
Ogg ouput using libvorbisfile
Hi, I'm new to writing any kind of sound program and somewhat new to C.
I am on linux and I've been trying to get the example code
(http://www.xiph.org/ogg/vorbis/doc/vorbisfile/example.html)for the
decoder using libvorbisfile to work. I think my main problem is output
to /dev/dsp. If I use the example where the only change I made were to
open a file instead of using stdin and I ouput
2015 Dec 02
2
A few questions about libvorbis from a newbie
First off, I don't even know if this is the right place to ask these kind
of questions, but I haven't been able to find answers anywhere else, so
1. I have found that "pcmTotal * vorbisInfo->channels * 2" gives the
uncompressed size of every ogg vorbis file I have used. What is a more
robust way of getting the full uncompressed file size?
2. How do I read a certain amount of
2015 Jun 14
2
Sound glitch when using libvorbisfile and libao
Hi Gunter,
Thank you for your quick response. As I mentioned in the email, I cannot
dependably reproduce it. It comes and goes, and I just have to wait for it
to come up before I can try to debug it. I've found it tends to happen when
I've been taxing my sound driver, but this isn't consistent either. My
inability to consistently reproduce this has made it a nasty bug for me to
2012 Jun 10
1
[libtremor] ov_read is reading past file size
I have a wav file which has been converted to an ogg file with libvorbis
via ffmpeg. However I've tested a few files just to make sure.
I run a standard while loop to using ov_read to pull all the data out of
ogg file. Using 4096 as the size to read each call. Watching my debug
logs it is reading 2048 bytes each call.
When I load the wav file the data chunk for the pcm data is 167680
2011 Jul 15
3
ov_read error on macosx
Hi, I have this code to decode ogg data:
unsigned long PSS_OggStream::DecodeOggVorbis(OggVorbis_File
*psOggVorbisFile, char *pDecodeBuffer, unsigned long ulBufferSize, unsigned
long ulChannels)
{
int current_section;
long lDecodeSize;
unsigned long ulSamples;
short *pSamples;
unsigned long ulBytesDone = 0;
while (true)
{
#ifdef WIN32
lDecodeSize = ov_read(psOggVorbisFile,
2006 May 11
1
Speed up?
Hello,
hope you're fine.
And hopefully someone can help me.
I wrote a short demonstration to show you my problem (see below). I'm
asking always for 64 samples. When "ov_read_float()" is finished, I
want to seek back to sample 1, and ask immediately for the next 64
samples.
But when I run this small app, I get an totally high CPU load.
Is there a way to it speed up?
Or do I