17 Apr
2004
17 Apr
'04
1:23 p.m.
On Fri, 16 Apr 2004 09:43:00 -0700 (PDT)
R Parker <rtp405(a)yahoo.com> wrote:
Hi,
As I've gone through my most challanging mastering
project, I've developed more questions than answers.
There's been reference, on this list, to documentation
that explains file formats-- I don't recall the
document title or where to find it. Ultimately, I need
a resouce that explains things like; the number of
available samples for the different bit depths (16bit
range from -ABC to +XYZ, 24bit...), DC offset is, peak
amplitude is, RMS is, etc.
Bits Range DC offset
-----------------------------------------
16 [-32768, +32767] 0
24 [-8388608, +8388607] 0
I need to know if samples are syncronous with decibel
level,
Que? I think you men synonymous rather than synchronous.
is maximum samples equal to 0db?
Yes, it is usually the case that 0dB is simply the maximum
sample value.
In the following sndfile-info report, what are Length
File length in bytes.
and Block Align?
An internal detail of how data is stored in a WAV file. In other
words, something you should ignore.
Version : libsndfile-1.0.6
========================================
File : guajira-jam.wav
Length : 30396228
RIFF : 30396220
WAVE
fmt : 16
Format : 0x1 => WAVE_FORMAT_PCM
Channels : 2
Sample Rate : 44100
Block Align : 4
Bit Width : 16
Bytes/sec : 176400
data : 30396184
End
----------------------------------------
Sample Rate : 44100
Frames : 7599046
Channels : 2
Format : 0x00010002
Sections : 1
Seekable : TRUE
Duration : 00:02:52.313
Signal Max : 25922
Is Signal Max a measurement of used samples?
No it is the maximum absoulute sample value. Since this is a
16 bit PCM file, the range of sample values is [-32768, +32767].
What I'll do is change that last line to:
Signal max : 25922 (-2.04dB)
Erik
--
+-----------------------------------------------------------+
Erik de Castro Lopo nospam(a)mega-nerd.com (Yes it's valid)
+-----------------------------------------------------------+
"In civilian equipment, such as computers, the number
of components alone makes miniaturization essential if
the computer is to be housed in a reasonable-sized
building." Electronics Oct. 1, 1957, p. 178