Data transfer integrity

9 replies [Last post]
Joined: Jun 27 2003

What software do you use to move video files around from drive(s) to drive on Macs ?

I was going to get ShotPut Pro until I read it doesn't check/validate the job very thoroughly - it only compares the file size I think - quite surprising as it's top dollar compared to most other software (some free) that does claim to verify copies if you want it and can spare the time.

ChronoSync ($40) looks like a good bet but DirSync Pro has verification and is free.

I could do it with Final Cut's Media Manager but it also has no verification option I can see.

mooblie's picture
Joined: Apr 27 2001

Correct me someone if I'm wrong, but I have always believed that ALL operating systems (from DOS, CP/M, System 6, and earlier - in fact, anything that works with discs) ALWAYS performs read-after-write verification checks, and so, if a copy completes without error, it completed..... without error i.e. positively checked as so, it's just that the OS doesn't bother to tell you, 'cos it's the norm.

Martin - DVdoctor in moderation. Everyone is entitled to my opinion.

foxvideo's picture
Joined: Sep 9 1999

:confused: Never used anything to verify since I started using Macs in 1994. I'll copy a file, check it, then delete the original, I don't ever remember a faulty transfer.

Dave Farrants Fox Video Editing

Joined: Jun 27 2003

Well there are checks and there are checks.
With camera original footage that must have at least two copies made (more when it comes to editing and then archiving to perhaps newer or larger discs etc), it's important in broadcast production to make sure the copies are identical to the original.
I use SynBack on my PC and it often reports one or two errors (unless you don't have that option switched on) with particular files and I just re-copy those files and usually it's fine second time.
Shooting with Varicam we use the P2 software to transfer ALWAYS as it has error checking built in, ditto with Sony cameras but those don't deal with other files on other drives.
THe Arri Alexa R3D Data Manager stores checksum data with the copied files so that even when the original is deleted the copy can be checked for inegrity (bit-rot) at any time afterwards. That software is working towards supporting the Convergent Design recorders (Gemini, Nano etc) files soon which would be ideal.

Joined: Mar 8 2007

My workflow is based around P2 and I always clone and verify the cards to a USB drive straight from the camera, the cloned drive is then used to load into FCP via log and transfer.

After that like others I just copy within the mac system and have never found any problems or lost any footage.

For my canon HF11 AVCD handycam I just load straight into FCP and then copy as required with no problems so far and have also sent all sorts of media away on MSDOS fat 32 drives with no loss of files.

Alan Roberts
Alan Roberts's picture
Joined: May 3 1999

I would be worried if I transferred files between computer drives and found errors in anything. I'd immediately suspect a faulty drive and set about replacing it.

Get my test cards document, and cards for 625, 525, 720 and 1080. Thanks to Gavin Gration for hosting them.
Camera settings documents are held by Daniel Browning and at the EBU
My book, 'Circles of Confusion' is available here.
Also EBU Tech.3335 tells how to test cameras, and R.118 tells how to use the results.

Joined: Jun 27 2003

Thanks for the input everyone.
Quite puzzled now but glad to have learnt some more things.
Hadn't even considered one of my new 2TB Hitachi drives might be patchy.
It would be interesting to compare standard OS copying against others somehow.

Joined: Jun 27 2003
RAM testing

Searching the SyncBack forum I found I might have faulty memory modules that causes the errors. I've downloaded MemTest as an ISO file and burnt it do CD to boot from to run that test app but it's not loading - I think I've done it wrong.

Does anyone know the right way to create a bootable CD with a program on it ? Just putting the downloaded mt410.iso file onto the disc and booting from it (I have checked that CD-ROM is the primary boot device in my boot up sequence) doesn't seem to be enough. Have I missed something out ?

harlequin's picture
Joined: Aug 16 2000

Burn the iso onto the disk , using iso image burn , not drop data file onto disk.
Suggest you use IMGBURN software

Gary MacKenzie ( an account only used for forum messages )

Thinkserver TS140 , 750ti Graphics card  & LG 27" uws led backlight , Edius 8

Humax Foxsat HD Pvr / Humax Fox T2 dvbt

Joined: Jun 27 2003

Thanks Gary. I tried and couldn't find image burn function in my existing software.
Sorted, now I've downloaded IMGBURN.