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speed47 / qpxtool

Enhanced (unofficial) qpxtool version
GNU General Public License v2.0
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Erroneous speed on BD-R scan #1

Closed speed47 closed 3 years ago

speed47 commented 3 years ago 
$ ./qscan -d F: -t errc
qScan 0.8.0 (C) 2007-2009  Gennady "ShultZ" Kozlov
qscan: using device 'F:': 'HL-DT-ST' 'BD-RE  WH16NS58 ' '1.V5'
ID: Supported write modes: Packet TAO SAO SAO/RAW SAO/16 SAO/96R SAO/96P RAW/16 RAW/96R RAW/96P LayerJump
qscan: Device not found in any plugin support list, trying to probe...
qscan: using plugin: LITEON
IM: ERRC data     : LDC BIS UNCR
Running BD Error Correction test at speed 12...

Testing 12219345 sectors: 0 - 12219344
          lba |        speed        |  LDC   BIS  |  UNCR
cur :   12288 | -477218.59 X -2147483648 kB/s |     0     0 |     0

This is the case because scan is done so fast than gettimeofday doesn't have an high-enough resolution to properly compute speed. We should use clock_gettime instead.

speed47 commented 3 years ago

Fixed version:

$ ./qscan -d F: -t errc
qScan 0.8.0 (C) 2007-2009  Gennady "ShultZ" Kozlov
qscan: using device 'F:': 'HL-DT-ST' 'BD-RE  WH16NS58 ' '1.V5'
ID: Supported write modes: Packet TAO SAO SAO/RAW SAO/16 SAO/96R SAO/96P RAW/16 RAW/96R RAW/96P LayerJump
qscan: Device not found in any plugin support list, trying to probe...
qscan: using plugin: LITEON
IM: ERRC data     : LDC BIS UNCR
Running BD Error Correction test at speed 12...

Testing 12219345 sectors: 0 - 12219344
          lba |        speed        |  LDC   BIS  |  UNCR
cur :   42848 |   4.99 X 22456 kB/s |     0     0 |     00