similar to: A few questions about libvorbis from a newbie

Displaying 20 results from an estimated 400 matches similar to: "A few questions about libvorbis from a newbie"

2015 Dec 04
1
A few questions about libvorbis from a newbie
Sorry about the personal reply Ian. I hope keeping the subject the same is the way to reply to the list (I have never used a mailing list before). The last thing I am not grasping is how *pcm_total *works without a concept of sample size? If the sample size is whatever I decide to read it as, how does it calculate the number of samples (of one channel I'm assuming because we have to multiply
2005 Nov 05
1
buffer overruns for small files
I wonder if anyone would have a comment on an experiment I have pretty much completed in my MFC/C++ project. With my simple libvorbis implementation, ogg decoding works just fine for files that are 10kb or larger. For anything smaller (actually, I don't have a 9kb file, so <= 8), it seems that I get an inaccurate value for ov_pcm_total. Though ov_read returns zero, I overflow the buffer
2002 Aug 03
1
vbr / cbr / abr API calls
Hi, Maybe this is documented somewhere, if so, please send me a link to the documentation. My question is: how to set up different (VBR, CBR, ABR) modes when calling the Ogg Vorbis API? Currently I do: CBR: ret = vorbis_encode_setup_managed( &vorbisInfo, getInChannel(), getOutSampleRate(),
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 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
2002 Jul 29
1
Where ov_read_float?
Subj!. Kind Regards, Michail. _________________________________ Michail A.Baikov, Linderdaum Team http://www.gamedot.ru http://linderdaum.gamedot.ru <p><p><p>--- >8 ---- List archives: http://www.xiph.org/archives/ Ogg project homepage: http://www.xiph.org/ogg/ To unsubscribe from this list, send a message to 'vorbis-dev-request@xiph.org' containing only the word
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:
2002 Sep 03
1
tremor relicensed as BSD
For those of you not of the commit mailing list, I wanted to point out that monty has checked the fixed-point 'tremor' vorbis decoder into xiph.org cvs, under the usual (free) xiph license. This was developed for use in embedded devices, so if you've been waiting for an interger-only (no fpu) implementation, you might want to give it a try. The code is in the 'Tremor' cvs
2003 Apr 30
1
float to PCM packing in libvorbisfile
Is there any particular reason why ov_read() packs floats to integer PCM inline, rather than being implemented in terms of ov_read_float() and a separate packing fucntion? There are obviously many advantages doing audio manipulation on the floats before packing, but right now you have to reinvent the packing stage yourself - in a replaygain backend that I'm working on, I ended up copying
2002 Apr 09
1
Replay Gain for vorbis
I had completely forgotten about Replay Gain until Mr. Seibert reminded me. Wasn't there talk of adding this to vorbis-tools? Anyway, I went here: http://sjeng.sourceforge.net/ftp/vorbis/ And downloaded the source for the replay gain tool. Unfortunately, I cannot compile it. The errors regard parameters to ov_read_float. Is there updated source somewhere else? -- -:-:-
2004 Aug 06
4
vorbis bitrates - offtopic
Hi, I'm experimenting with IceCast2, using DarkIce to generate the stream. I have found some peculiarities with the vorbis bitrates. In DarkIce, I call vorbis_encode_init() with about the following values: vorbis_encode_init( &vorbisInfo, 2, 44100, 96, 96, 96); which by all reasons should generate a 96 kb/s stream, as all max_bitrate, nominal_bitrate and min_bitrate are set to 96.
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 Dec 04
1
A few questions about libvorbis from a newbie
I am deeply sorry about the corrupt message just being sent; there seems to have been a compatibility issue with my mailer and my browser. This is an identical copy of the previous message: Hello Martin, Vorbis encoders are lossy, which is in a sense equivalent to converting the sample size of the raw PCM stream into something that would result in the desired bitrate. The "sample size"
2002 Aug 20
1
managed mode / max bitrate doesn't have effect
Hi, I'm experimenting with managed mode encoding with specifying maximum bitrate. I call: vorbis_encode_init( &vorbisInfo, 2, 44100, -1, 96000, 96000); to initialize the encoding. To my surprise, it seems the maxbitrate value of 96000 doesn't have an effect, the bitrate of the
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
2004 Aug 06
2
vorbis_encode_init() bitrate arguments - offtopic
Hi, It's a bit offtopic for this list, but you might be able to help. For libvorbis rc3, what is the correct bitrate parametrization for the call vorbis_encode_init()? For rc2, it worked calling it the following way: vorbis_encode_init( &vorbisInfo, 2, // two channels 44100, // 44.1kHz
2002 Jul 21
1
Vorbis 1.0 DLLs
My compiler isn't locating 'ov_read_float' from the prebuilt vorbisfile.dll. Was that function missed from vorbisfile.def before compilation of the Windows SDK files? <p><p>J. <p>--- >8 ---- List archives: http://www.xiph.org/archives/ Ogg project homepage: http://www.xiph.org/ogg/ To unsubscribe from this list, send a message to