Sponsored Content
Top Forums UNIX for Dummies Questions & Answers How to decrypt audio data from magnetic tapes? Post 302897696 by NICEPeppino on Tuesday 15th of April 2014 12:50:31 PM
Old 04-15-2014
Thank you Corona for your reply,

I have extracted some calls using the original software but it was a very long job. I cannot extract more than one call per time. Given the fact that the tape contains 10000 calls it is very slow.
The program I use is a proprietary backup tool, however, it uses common compression format: PCM and ADPCM. The tape stores calls grouped by recording channel. Each tape records 128 channels

Using the dd command I copied just 165 MB of data despite the fact the tape is 20 GB. Why? I think it is because it reads the first channel and than stops. 165Mb x 128 channels = (21120) the tape is dds4 20 gb so this should be the reason.
This is the command:

dd if=/dev/nst0 bs=32K of=output_file

How can I open the data extracted with the dd or other commands? If this info is not enough, what should I look at to decrypt the data?
 

9 More Discussions You Might Find Interesting

1. Programming

Magnetic card readers

i can't find any info on developing for magnetic card readers in the unix environment. I'm developing a POS system and i want it to include credit card verification. Any direction would be hot... (6 Replies)
Discussion started by: Gekko
6 Replies

2. UNIX for Dummies Questions & Answers

tapes

is there a command to check unoccupied space on a tape ? AIX 3.2 (1 Reply)
Discussion started by: cubicle^dweller
1 Replies

3. UNIX for Dummies Questions & Answers

Tapes

:confused: Hello!! I am a new UNIX user, and I need to back up some files, I have some old ones and I have been trying to delete the old information with 'mt erase' but I don't be sure if it works, and 'mt resert' but the it gave a message suggesting me to use 'scsiha -r' (but the last one... (1 Reply)
Discussion started by: scs
1 Replies

4. UNIX for Dummies Questions & Answers

MSR magnetic stripe card reader

Hi all I am working on MSR110 ...Can anyone plz tell me how to use the configuration commands with magnetic reader???. Please help me out as i have to develop API in C on linux platform.MSR110 is not responding to the configuration commands. Please help... Regards Mahima (0 Replies)
Discussion started by: mahima_er
0 Replies

5. Solaris

Magnetic Tape

Hello All, I am facing some problem with magnetic tape drive. Backups are coming properly with the tapes that we had previously mt st give o/p as below .. root@server1:/ 2ksh# mt st Quantum Super DLT 320 tape drive: sense key(0x6)= Unit Attention residual= 0 retries= 0 file... (1 Reply)
Discussion started by: ailnilanjan
1 Replies

6. Solaris

vxdump with more tapes

Hi Community, I've a V440 Sun Server with 2 device tape of 72GB. I have to backup a folder of 80 GB, so I have to use 2 tapes of 72GB (144 GB); If I use vxdump command which are the options that I have to use? When the first tape finishes does the system stop the backup? Please help me... (1 Reply)
Discussion started by: Sunb3
1 Replies

7. UNIX for Advanced & Expert Users

Listing/copying files from magnetic optical disk

I am trying to list the name of files on an MOD - I use the command tar vtf /MOD_DRIVE|more and I get a nice list of filenames/directories on this particular MOD. When I put in another MOD that contains software options I get the error "directory checksum error". I would like to be able to... (2 Replies)
Discussion started by: drew_holm
2 Replies

8. AIX

Moving tapes

Hello, anybody out there that is using itdt to manage tape changes in a tape library. The help of itdt show a move subcommand but I can't get it to work. Env: AIX5.3 Dell PowerVault TL2000 tape library -> rmt1 Available 01-08-02 IBM 3580 Ultrium Tape Drive (FCP) # itdt says it finds the... (3 Replies)
Discussion started by: petervg
3 Replies

9. Slackware

Problems with audio recording in Audacity 2.0.5. Slackware64 14.1; Intel HD Audio.

I'm trying to record audio using Audacity 2.0.5 installed from SlackBuilds. My system is 64-bit Slackware 14.1 and a sound card is Intel HD Audio. I didn't change my sound system to OSS. (Default sound system in Slackware 14.1 is ALSA, isn't it?) First, I set Internal Microphone slider in KMix... (2 Replies)
Discussion started by: qzxcvbnm
2 Replies
mt(1)							      General Commands Manual							     mt(1)

Name
       mt - magnetic tape manipulating program

Syntax
       mt [-f tapename] command [count]

Description
       The command permits the operation of a magnetic tape drive.

Options
       The  -f	flag  option  uses  the specified tape device (next argument) in place of either that tape device defined by your TAPE environment
       variable (.login or .profile) or /dev/nrmt0h.

       Some operations may be performed multiple times by specifying count.  By default, performs the requested operation once.

       The command argument defines the operation to be performed.  Only as many characters as are required to uniquely identify a command need be
       specified.

       The following is a list of commands:

       bsf		   Backspace count files.

       bsr		   Backspace count records.

       cache		   Allows to use the cache buffer on a tape drive that has the cache buffer feature.

       clhrdsf		   Clear  hardware/software problem.  Works with tape drives which use the TMSCP tape controller interface This command is
			   restricted to root access only.

       clserex		   Clear serious exception.  Works with tape drives which use the TMSCP tape controller interface

       clsub		   Clear subsystem.  Works with tape drives which use the TMSCP tape controller interface This command	is  restricted	to
			   root access only.

       eof, weof	   Write count end-of-file marks at the current position on the tape.

       eotdis		   Disable  end-of-tape  detection.   When the end of tape is reached, the tape will run off the reel.	Only the superuser
			   can issue this command.  The command remains in effect for the device until end-of-tape detection is enabled  with  the
			   eoten command.

       eoten		   Enable  end-of-tape	detection.   When the end-of-tape markers are reached, the tape is halted on the reel, between the
			   two end-of-tape markers.  Only the superuser can issue this command.  The command remains  in  effect  for  the  device
			   until end-of-tape detection is disabled with the eotdis command.  This is the default mode after a system boot.

       fsf		   Forward-space count files.

       fsr		   Forward-space count records.

       nocache		   Disables the use of the cache buffer for any tape drive that has the cache buffer feature.

       offline, rewoffl    Rewind the tape and place the tape unit off-line.

       retension	   Retensions the tape.  Retension means moving the tape one complete pass between EOT and BOT.

       rewind		   Rewind the tape.

       status		   Print status information about the tape unit.

Examples
       This example shows how to rewind the tape
       mt -f /dev/rmt0l rewind
       This example shows how to backspace the tape nmt1h three files:
       mt -f /dev/nrmt1h bsf 3
       This example shows how to write two end-of-file marks at the current position on tape nmt6h:
       mt -f /dev/nrmt6h eof 2

Return Values
       In  shell  scripts, returns a 0 exit status when the operation(s) were successful, 1 if the command was unrecognized, and 2 if an operation
       failed.

Files
       /dev/rmt?h or /dev/rmt?l
		 Raw magnetic tape interface with rewind when closed

       /dev/nmt?h or /dev/nmt?l
		 Raw magnetic tape interface with no rewind when closed

See Also
       dd(1), tar(1), ioctl(2), mtio(4), tms(4), environ(7)

																	     mt(1)
All times are GMT -4. The time now is 12:02 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy