pelgrims
I have a strange issue in regards to MP3 Bitrates meaning:
I put a song in a folder and then analyze the song through VDJ when I then right-click on the file & ask for the file info (still in Vdj) it shows me bitrate, Freq,etc.
Till so far all normal BUT: say that for ex. The file then shows up being bitrate “128” & when I go to the file directly (via windows browser) & click right & say properties it shows me bitrate 325 or whatever the original bitrate is??
Iaw. Does VDJ lower the bitrate when analyzing? And when yes why?
I put a song in a folder and then analyze the song through VDJ when I then right-click on the file & ask for the file info (still in Vdj) it shows me bitrate, Freq,etc.
Till so far all normal BUT: say that for ex. The file then shows up being bitrate “128” & when I go to the file directly (via windows browser) & click right & say properties it shows me bitrate 325 or whatever the original bitrate is??
Iaw. Does VDJ lower the bitrate when analyzing? And when yes why?
发表时间 Thu 21 Jun 07 @ 4:12 pm
digimixer
No VDJ does not change the bitrate.
MP3 files have tags assocaited with them. One of these tags is the Bitrate. However, anyone can change the info in this tag so it isn't necessarily accurate.
You can normally get a good idea of the bitrate by comparing the length of the track by the size of the MP3 file
For example a 5 minute track @ 128kb bitrate is normally around the 5mb size (approx)
MP3 files have tags assocaited with them. One of these tags is the Bitrate. However, anyone can change the info in this tag so it isn't necessarily accurate.
You can normally get a good idea of the bitrate by comparing the length of the track by the size of the MP3 file
For example a 5 minute track @ 128kb bitrate is normally around the 5mb size (approx)
发表时间 Thu 21 Jun 07 @ 5:10 pm
digimixer
For a more exact approach, see below
Bitrate (kb) = ( Size of Music File in KB / (Length of track in seconds)) * 8
To put this into practice, Say for example you had a 5mb file which lasted 5 mins
5mb= 5120KB
5 mins = 300 seconds
so...
Bitrate = ( 5120 / 300) * 8
Bitrate = ( 17.066) * 8
Bitrate = 136.53 kb
**You have to multiply by 8 as there are eight bits in a Byte **
Bitrate (kb) = ( Size of Music File in KB / (Length of track in seconds)) * 8
To put this into practice, Say for example you had a 5mb file which lasted 5 mins
5mb= 5120KB
5 mins = 300 seconds
so...
Bitrate = ( 5120 / 300) * 8
Bitrate = ( 17.066) * 8
Bitrate = 136.53 kb
**You have to multiply by 8 as there are eight bits in a Byte **
发表时间 Thu 21 Jun 07 @ 5:38 pm
DJ-ALF
You just might have Variable Bit rate that is changing depending on the track information. I use only 192k Constant Bit rate. VDJ is not changing your bit rate when analyzing.
发表时间 Thu 21 Jun 07 @ 6:07 pm
bagpuss
You are using VBR MP3 files, 128kbps is the minimum bite rate of your VBR's, that's why they are showing up in VDJ as 128kbps, Windows explorer shows the maximum, which could be 320kbps for example, both could be deemed inaccurate, it's best to take an average bite rate of a VBR in order to know its true quality.
You should use a bite rate that's suitable for your needs and ability to store, personally I use the maximum bite rate I can (Club DJ & Perfectionist), I rip CDs at 320kbps CBR and buy most MP3's at 320kbps, some tracks are only available on sites that offer 192kbps (MAX), I find these quite acceptable, the difference in sound is tiny.
You should use a bite rate that's suitable for your needs and ability to store, personally I use the maximum bite rate I can (Club DJ & Perfectionist), I rip CDs at 320kbps CBR and buy most MP3's at 320kbps, some tracks are only available on sites that offer 192kbps (MAX), I find these quite acceptable, the difference in sound is tiny.
发表时间 Thu 21 Jun 07 @ 8:13 pm
Andrew87
Virtual DJ is awful with detecting bitrate for VBR files but don't worry, your file isn't being modified in any way. What is reports is however not the minimum bitrate the song contains, I don't know why it's so far off. Windows reporting isn't too great after, although MS seem to have improved things with WMP10/11.
发表时间 Thu 21 Jun 07 @ 10:36 pm
pelgrims
Thanks guys, feeling much better already :-)
Regards,
Regards,
发表时间 Fri 22 Jun 07 @ 8:25 am
Rune (DJ-In-Norway)
VBR in VDJ works super fine for audio, as it should, using LAME Mp3 decoder (very good decoder)
As for tag, some or most VBR files show wrong tag info, and as far as I know it shows the lowest part of a variable bitrate file.
So and MP3 file coded at VBR 128~329 (128b in quiet areas, 320b in music areas), will show as 128b in VDJ ID tag reads.
But it plays the audio just asit should.. ;) no worries
发表时间 Fri 22 Jun 07 @ 7:38 pm
Andrew87
It doesn't show the lowest value. If that were true most of my files would show 0-32 kbps as I use -v 1 --vbr-new settings to encode.
VDJ reports 128 when the encoder states that there was at least one frame of 32kbps, another of 80, 9 frames at 96 kbps etc.
Quote :
Command: F:\Programs\RazorLame v1.1.5a\codec\lame.exe -V 1 --vbr-new "C:\Users\Andrew\Music\Compilations\Jungle Sound Gold\117 Foreigner.mp3" "C:\Users\Andrew\Desktop\117 Foreigner.mp3"
ID3v2 found. Be aware that the ID3 tag is currently lost when transcoding.
LAME 3.97 32bits (http://www.mp3dev.org/)
CPU features: MMX (ASM used), SSE (ASM used), SSE2
Using polyphase lowpass filter, transition band: 18671 Hz - 19205 Hz
Encoding C:\Users\Andrew\Music\Compilations\Jungle Sound Gold\117 Foreigner.mp3
to C:\Users\Andrew\Desktop\117 Foreigner.mp3
Encoding as 44.1 kHz VBR(q=1) j-stereo MPEG-1 Layer III (ca. 6.5x) qval=3
Can't step back 98!
32 [ 1] *
40 [ 0]
48 [ 0]
56 [ 0]
64 [ 0]
80 [ 1] *
96 [ 9] *
112 [ 365] ******
128 [1934] *****************************
160 [4577] ********************************************************************
192 [1183] ******************
224 [ 648] %*********
256 [ 591] %********
320 [ 391] ******
Encoded one file in 0:00:17
ID3v2 found. Be aware that the ID3 tag is currently lost when transcoding.
LAME 3.97 32bits (http://www.mp3dev.org/)
CPU features: MMX (ASM used), SSE (ASM used), SSE2
Using polyphase lowpass filter, transition band: 18671 Hz - 19205 Hz
Encoding C:\Users\Andrew\Music\Compilations\Jungle Sound Gold\117 Foreigner.mp3
to C:\Users\Andrew\Desktop\117 Foreigner.mp3
Encoding as 44.1 kHz VBR(q=1) j-stereo MPEG-1 Layer III (ca. 6.5x) qval=3
Can't step back 98!
32 [ 1] *
40 [ 0]
48 [ 0]
56 [ 0]
64 [ 0]
80 [ 1] *
96 [ 9] *
112 [ 365] ******
128 [1934] *****************************
160 [4577] ********************************************************************
192 [1183] ******************
224 [ 648] %*********
256 [ 591] %********
320 [ 391] ******
Encoded one file in 0:00:17
VDJ reports 128 when the encoder states that there was at least one frame of 32kbps, another of 80, 9 frames at 96 kbps etc.
发表时间 Fri 22 Jun 07 @ 8:11 pm
GargantulaKon
I trust this page below to help me decide what settings to use for LAME for a decent quality vs size ratio. They suggest to use LAME 3.97. If I had the hard drive space and Virtual DJ supported it, I might switch over to FLAC and re-rip my CDs and WAV files again.
http://wiki.hydrogenaudio.org/index.php?title=Lame
I personally use the command line switch and set RazorLame to only use this as the variables, "-V2 --vbr-new".
I use Goldwave to convert to PCM signed 16 bit 44.1 kHz wav (Is this good? It was the default for WAVs) and then RazorLame to encode multiple files form one format to another and I use EAC in secure mode to rip from CDs flawlessly. Though, it takes a really long time to get through one CD.
http://wiki.hydrogenaudio.org/index.php?title=Lame
I personally use the command line switch and set RazorLame to only use this as the variables, "-V2 --vbr-new".
I use Goldwave to convert to PCM signed 16 bit 44.1 kHz wav (Is this good? It was the default for WAVs) and then RazorLame to encode multiple files form one format to another and I use EAC in secure mode to rip from CDs flawlessly. Though, it takes a really long time to get through one CD.
发表时间 Fri 31 Aug 07 @ 9:50 pm
Andrew87
VirtualDJ's new bitrate reporting is still bad. If the songs filesize and filelength are stored in the database then why does VirtualDJ report a random cbr number which is way off with vbr tracks?
A far more accurate calculation, yet still wrong would be: filesize(kB) / filelength(sec) * 8
the container size (exluding tags and things such as albumart) still needs to be worked into that, but it's better to report a 182kbps track as 190kbps or something than it is 128!
It should be possible to get the exact bitrate too, as when you're analysing a file VirtualDJ will access every frame of the mp3. Then it just has to do an average of the frames.
A far more accurate calculation, yet still wrong would be: filesize(kB) / filelength(sec) * 8
the container size (exluding tags and things such as albumart) still needs to be worked into that, but it's better to report a 182kbps track as 190kbps or something than it is 128!
It should be possible to get the exact bitrate too, as when you're analysing a file VirtualDJ will access every frame of the mp3. Then it just has to do an average of the frames.
发表时间 Fri 31 Aug 07 @ 10:18 pm