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
AFGETFRAMECOUNT(3)														AFGETFRAMECOUNT(3)

NAME
afGetFrameCount, afGetTrackBytes, afGetDataOffset - get the total sample frame count, length of audio track in bytes, offset of the audio track for a track in an audio file SYNOPSIS
#include <audiofile.h> AFframecount afGetFrameCount (AFfilehandle file, int track); AFfileoffset afGetTrackBytes (AFfilehandle file, int track); AFfileoffset afGetDataOffset (AFfilehandle file, int track); PARAMETERS
file is an audio file handle created by a previous call to afOpenFile(3). track is an integer which specifies an audio track within file. All supported file formats contain exactly one audio track per file, so the constant AF_DEFAULT_TRACK should always be used. DESCRIPTION
afGetFrameCount returns the total number of sample frames contained within the specified track of the specified file. Each sample frame of audio consists of a fixed number of samples (equal to the number of audio channels in the track. For monaural data, a sample frame consists of one audio sample. For stereophonic data, a sample frame consists of a stereo pair. afGetTrackBytes returns the total number of bytes of raw audio data (i.e., prior to decompression or conversion) in the track. afGetDataOffset returns the offset in bytes of the start of the audio data contained within the specified track of the specified file. RETURN VALUE
afGetFrameCount returns the total number of sample frames in track. afGetTrackBytes returns the total number of bytes of audio data in track. afGetDataOffset returns the offset in bytes to the beginning of the audio data in track. Each of these routines returns -1 in case of error. AUTHOR
Michael Pruett <michael@68k.org> Audio File Library 0.3.6 03/06/2013 AFGETFRAMECOUNT(3)
All times are GMT -4. The time now is 06:24 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy