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Tech: SD card recovery programmes

GUEST,Bluesman 16 Dec 11 - 03:47 PM
GUEST,999 16 Dec 11 - 04:17 PM
GUEST,999 16 Dec 11 - 04:20 PM
GUEST,Bluesman 16 Dec 11 - 04:50 PM
number 6 16 Dec 11 - 05:14 PM
GUEST,Jon 16 Dec 11 - 05:18 PM
GUEST,Bluesman 16 Dec 11 - 05:25 PM
Tangledwood 16 Dec 11 - 05:41 PM
GUEST,Jon 16 Dec 11 - 05:46 PM
GUEST,Jon 16 Dec 11 - 05:47 PM
GUEST,Bluesman 16 Dec 11 - 05:51 PM
GUEST,Jon 16 Dec 11 - 06:02 PM
GUEST,Bluesman 16 Dec 11 - 06:06 PM
GUEST,999 16 Dec 11 - 06:09 PM
GUEST,Jon 16 Dec 11 - 06:10 PM
GUEST,Bluesman 16 Dec 11 - 06:13 PM
GUEST,Bluesman 16 Dec 11 - 06:23 PM
GUEST,Jon 16 Dec 11 - 06:31 PM
GUEST,Bluesman 16 Dec 11 - 06:48 PM
GUEST,999 16 Dec 11 - 06:52 PM
GUEST,Bluesman 16 Dec 11 - 06:55 PM
GUEST,Jon 16 Dec 11 - 06:57 PM
GUEST,999 16 Dec 11 - 07:06 PM
GUEST,Bluesman 16 Dec 11 - 07:16 PM
GUEST,Bluesman 16 Dec 11 - 07:22 PM
GUEST,Jon 16 Dec 11 - 08:02 PM
GUEST,Bluesman 16 Dec 11 - 08:17 PM
EBarnacle 16 Dec 11 - 08:22 PM
GUEST,Bluesman 16 Dec 11 - 08:23 PM
GUEST,Bluesman 16 Dec 11 - 08:28 PM
GUEST,Bluesman 16 Dec 11 - 08:38 PM
GUEST,Jon 16 Dec 11 - 10:03 PM
JohnInKansas 16 Dec 11 - 10:45 PM
GUEST,999 16 Dec 11 - 10:54 PM
GUEST,Jon 17 Dec 11 - 05:39 AM
GUEST,Bluesman 17 Dec 11 - 07:49 AM
JohnInKansas 17 Dec 11 - 05:31 PM
GUEST,Jon 17 Dec 11 - 05:51 PM
GUEST,Jon 17 Dec 11 - 06:46 PM
JohnInKansas 17 Dec 11 - 09:36 PM
GUEST,Jon 17 Dec 11 - 09:59 PM
GUEST,Jon 17 Dec 11 - 10:28 PM
JohnInKansas 17 Dec 11 - 10:35 PM
GUEST,Jon 17 Dec 11 - 10:44 PM
JohnInKansas 18 Dec 11 - 02:18 AM
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Subject: BS: SD card recovery programmes
From: GUEST,Bluesman
Date: 16 Dec 11 - 03:47 PM

One of my SD cards keeps throwing up the message that it needs formatted. I downloaded a programme to recover the files, it recovered the files okay, then offered a buy now to obtain them and it was very expensive. Anyone know a trusted programme that works and is reasonably price.

Thanks in anticipation.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,999
Date: 16 Dec 11 - 04:17 PM

BM, I cannot attest to the site on the following link. It;s a freeware site. But give it a boo. Ain't right to lose 'memories' because of some computer glitch. Best of luck.

BTW, there are some real heavy computer dudes/dudettes on this site, so give it a few hours for your thread to be noticed.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,999
Date: 16 Dec 11 - 04:20 PM

PS No offense, but this thread would have been better with a Technology label as opposed to BS.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Bluesman
Date: 16 Dec 11 - 04:50 PM

Big thanks for taking the time to respond 999, means a lot. It is a card that should have been transferred onto my external hard drive. Load of photographs of my army service days and departed mother and father. Again thanks.


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Subject: RE: BS: SD card recovery programmes
From: number 6
Date: 16 Dec 11 - 05:14 PM

Some clarification required Bluesman

Where were the photos sourced from .... a camera, or are they scanned photos where they were loaded directly onto the card from a hard drive via a a USB card reader

Are you trying to load the photos onto your hard drive from a camera .... or USB card reader?

If the card you are using was loaded directly from a hard drive and you are using a digi camera to loaded them back onto a hard drive you will encounter a format error, the same error will happen if the photos are sourced from a different model of camera that you are trying to load them with.

If you have taken a bunch of photos on a digi camera and suddenly you encounter a format error .... my experience is that you are pretty well SOL .... with that in saying I haven't experienced that type of error since way back on the earlier models of digi cameras.

biLL

biLL


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Jon
Date: 16 Dec 11 - 05:18 PM

I've not used it but Photorec might be worth a try.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Bluesman
Date: 16 Dec 11 - 05:25 PM

Bill, it's an 8gb Sandisk card loaded up with scanned photographs. It was working fine yesterday, put it in today and message appears "disk in drive is not formatted, do you want to format it now ? " that would clear the photographs off the card. I tried a programme I downloaded, all the photographs appeared, so did the cost of the programme !


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Subject: RE: BS: SD card recovery programmes
From: Tangledwood
Date: 16 Dec 11 - 05:41 PM

Sandisk provide a free download of RescuePro if you buy an "Extreme" or "Extreme Pro" card. These cards aren't cheap but if you're in need of another card it might be a solution.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Jon
Date: 16 Dec 11 - 05:46 PM

Trying photorec on one of my 8GB cards now. It's a text interface but its easy to navigate. Instructions are here

Apparently it will take over an hour to scan the whole card.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Jon
Date: 16 Dec 11 - 05:47 PM

Photorec instructions


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Bluesman
Date: 16 Dec 11 - 05:51 PM

Tried
http://www.cardrecovery.com/

It threw up all the photographs on screen in five minutes, cost $40.00 to complete. Should I run with it?


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Jon
Date: 16 Dec 11 - 06:02 PM

I can't answer for you but if my choice was between photocrec which takes over an hour and cardrecovery which takes 5 minutes providing both do the job, personally I would not be paying out $40 for more or less a one off need.

On the other hand, if I felt my need was likely to be frequent, I probably would consider paying out for the faster software.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Bluesman
Date: 16 Dec 11 - 06:06 PM

Jon, what is the cost of photocrec, I can't seem to be able to see a charge, I agree, it will most likely be a one off.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,999
Date: 16 Dec 11 - 06:09 PM

Blues, don't forget to check the system requirements on the cardrecovery.com site. Bottom of the page that opens.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Jon
Date: 16 Dec 11 - 06:10 PM

Photorec is free open source software (GNU GPL licenced) software.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Bluesman
Date: 16 Dec 11 - 06:13 PM

999 and Jon, both of you have been gems tonight, heading onto it now, will let you know how I get on.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Bluesman
Date: 16 Dec 11 - 06:23 PM

Sorry for being thick, but photorec is downloading as a zipper file, can't open it.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Jon
Date: 16 Dec 11 - 06:31 PM

Winzip is probably the best known Windows utility for this but I think you have to pay for this at some point. Camunzip seems to be an alternative.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Bluesman
Date: 16 Dec 11 - 06:48 PM

Lot of pages with black backgrounds coming up, now I am lost ahhhhhhhhhhhhh


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Subject: RE: BS: SD card recovery programmes
From: GUEST,999
Date: 16 Dec 11 - 06:52 PM

Blues, what operating system do you use?


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Bluesman
Date: 16 Dec 11 - 06:55 PM

Windows xp


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Jon
Date: 16 Dec 11 - 06:57 PM

I'm away from the PC for a while now. Have just looked at the results for my try with photorec.

309 files recovered, mix of ogg, flac, wav and mp3 seems about right and the files I've tried open OK.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,999
Date: 16 Dec 11 - 07:06 PM

I'll send a message to JohninKansas and maybe he can come up with something. Hang tough.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Bluesman
Date: 16 Dec 11 - 07:16 PM

999, it is recovering my past history, not the SD card ! Is there a version for a thick old fart like me out there ?


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Bluesman
Date: 16 Dec 11 - 07:22 PM

It is recovering away here, no mention of a usb or external SD card among the list of items being recovered though !


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Jon
Date: 16 Dec 11 - 08:02 PM

Sounds like you might be recovering the hard drive! I'd stop and quit if that's the case.

I'm afraid I'm on Linux but the first page asks you to to select the drive:

PhotoRec 6.12, Data Recovery Utility, May 2011                                                                                                      
Christophe GRENIER                                                                                                          
http://www.cgsecurity.org                                                                                                                           
                                                                                                                                                   
PhotoRec is free software, and                                                                                                                  
comes with ABSOLUTELY NO WARRANTY.                                                                                                                  
                                                                                                                                                   
Select a media (use Arrow keys, then press Enter):                                                                                                
>Disk /dev/sda - 203 GB / 189 GiB (RO) - ATA Maxtor 6L200M0                                                                                       
Disk /dev/sdb - 160 GB / 149 GiB (RO) - ATA SAMSUNG HD161HJ                                                                                       
Disk /dev/sdc - 750 GB / 698 GiB (RO) - ATA Hitachi HDS72107                                                                                       
Disk /dev/sdh - 3999 MB / 3814 MiB (RO) - ZOOM H4 SD R&W                                                                                          
                                                                                                                                                
>[Proceed ] [ Quit ]                                                                                                                           
                                                                                                                                                   
Note:                                                                                                                                             
Disk capacity must be correctly detected for a successful recovery.                                                                                 
If a disk listed above has incorrect size, check HD jumper settings, BIOS                                                                           
detection, and install the latest OS patches and disk drivers.      


In my case, I'd want to move down to /dev/sdh. I'd guess with Windows it would be some drive from E: on. The size of the disk should give a clue.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Bluesman
Date: 16 Dec 11 - 08:17 PM

Yes, downloaded my hard drive lol


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Subject: RE: BS: SD card recovery programmes
From: EBarnacle
Date: 16 Dec 11 - 08:22 PM

If all else fails, consider buying [yes, I know that's money] a USB card reader. They tend to be somewhat flexible about odd [read old]formats.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Bluesman
Date: 16 Dec 11 - 08:23 PM

Think I have cracked it, I see an 8 and the letters sd. Fingers crossed.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Bluesman
Date: 16 Dec 11 - 08:28 PM

EBarnacle, using a card reader, no other way of getting card into computer. Yes we are on the move now okay, the card reader is flashing away here, it seems to be that last post of yours Jon that did it.

999 and Jon I cannot thank you both enough for your time, understanding and help, it is remembered.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Bluesman
Date: 16 Dec 11 - 08:38 PM

Glad to report that all photographs have been safely recovered. Would not have been possible without your help. I am extremely grateful to both you guys. Right, I have hair in the first five photographs, can you restore that too ????

Regards with eternal gratitude.


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Subject: RE: BS: SD card recovery programmes
From: GUEST,Jon
Date: 16 Dec 11 - 10:03 PM

Good news.

I notice your run with photorec got through a lot faster than mine.


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Subject: RE: BS: SD card recovery programmes
From: JohnInKansas
Date: 16 Dec 11 - 10:45 PM

I've had a few problems with downloading from a Camera that the computer refuses to recognize. I get a message saying I need a driver, but Canon says there isn't one and that I don't need to have one anyway.

The solution has been to take the SD card out of the camera and put it in a card reader, and that's worked okay so far. It's possible that the reader interface adds something to the hookup - or takes some source of confusion out. The little "pocket readers" are pretty cheaply made, and somewhat prone to erratic contact problems after they've been used a few times, but ones built into the computer or a printe/scanner should be a little more reliable. (note the "should.")

I'm afraid I haven't encountered a use for a file recovery program, since all of my "drive failures" in the past couple of years have been "sudden lack of spin."

Many SD cards were delivered with FAT format, but now some apparently are preformatted NTFS, so there's some ambiguity about what yours might be. WinXP should be able to read either, but another device like a scanner or camera might prefer "the other one."

When using them in a device, it's generally recommended that reformatting should be done only by the box you use them in and most things you can stick an SD card into have built in Format capability.

Problems that might be similar to what you found have been reported by camera users who formatted their SD card using the computer's "FORMAT" instead of the camera's. (Apparently even if the card is in the camera when they do it?). You didn't say what kind of device put the files on the SD card, but a mismatch between the card format and some details of what the box that wrote the stuff on it expected might - based on the recent gossip - have been part of the problem. I haven't run into anyone offering an explanation of why that might be the case, though.

Now that you have the files safely off, you might want to use some caution about how much you put back on the card, at least until you've run a few write/read cycles through it = even if you do reformat it before you continue using it.

Too late to be any help, and wouldn't have been able to offer much earlier; but couldn't resist joining the gossip circle.

John


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Subject: RE: BS: SD card recovery programmes
From: GUEST,999
Date: 16 Dec 11 - 10:54 PM

Great news, Blues. I'm very happy for you.

Hey, you computer guys are something else.


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Subject: RE: Tech: SD card recovery programmes
From: GUEST,Jon
Date: 17 Dec 11 - 05:39 AM

I've just had another look at the websites for two of the programs we mentioned.

A difference I notice between the free multi platform photorec and the Windows only CardRecover is the file formats recovered.

CardRecover supports JPG JPEG TIF AVI MPG MOV MPEG ASF MP4 3GP MTS MP3 WAV and a number of raw photo formats.

PhotoRec supports over 300 and includes Office formats, archive formats, etc. as well as media ones. List here

At a quick look I think CardRecover probably supports more camera specific raw files. PhotoRec does provide a mechanism to add ones own custom formats though.


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Subject: RE: Tech: SD card recovery programmes
From: GUEST,Bluesman
Date: 17 Dec 11 - 07:49 AM

Thank God Jon thanks to your advice I recovered all off mine.
Keith


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Subject: RE: Tech: SD card recovery programmes
From: JohnInKansas
Date: 17 Dec 11 - 05:31 PM

If "recover" is used in the meaning of simply copying files from a place that is behaving badly, the file format shouldn't seem to make any difference in most cases. All that's required is finding where the file starts and copying the bits that come after that. (Windows since Vista, at least theoretically, has a utility built in with the "Advanced Administration" Tools that's supposed to be able to do magic on "lost files." I don't know if anything similar is in WinXP, but it's apparently a well guarded secret even in later versions, and may not be in "Home Basic" kits. And since I haven't tried it I'm willing to assume it probably doesn't work, but ... .

Even if the file is in a form for which you don't have a program that can display that format it would seem that you should be able to copy the file from one place to another regardless of format, with tools commonly used for hard drives, floppies, and such.

Finding the bits and making a copy depends on features of the storage medium, and quite a few programs seem to be able to handle both HDs and Memory cards easily enough, but the copying capability has almost nothing to do with what kind of file you're messing with.

That random and arbitrary leap in logic seems to lead to the suggestion that perhaps programs mentioned also attempt to "put the bits back" in the individual files that are corrupted in some way in the original storage place. It would be reasonable that the program would need to know an original format to restore a corrupted file back to a good copy, and that likely would require a fairly specialized program that would be dependent on format of the files.

Recognizing that getting a software seller (or distributor) to actually tell you what a given program is supposed to do is usually an impossible task, does anyone know, or care to speculate on, what exotic capabilities the programs mentioned may have in addition to the ability to make copies from one place to another - if any? (Aside from being "wonderful" and "necessary," which all distributors are willing to proclaim for them all.)

John


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Subject: RE: Tech: SD card recovery programmes
From: GUEST,Jon
Date: 17 Dec 11 - 05:51 PM

I believe the technical term for the type of recovery used by photorec (and I am assuming the other) is "file carving".

As far as I understand it, it works by reading the disk blocks one at a time, attempting to match the start to the blocks with "signatures", or patterns to identify known file formats.

It can only recover file formats it has signatures for. Also, the recovery program needs to be able to supply an file extension to apply to the recovered file for the user.


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Subject: RE: Tech: SD card recovery programmes
From: GUEST,Jon
Date: 17 Dec 11 - 06:46 PM

I'm drifting, but Microsoft's best recovery utility was the old MSDOS recover command.

Used wrongly, it would merrily "recover" your hard disk, converting everything to files named FILEnnnn.REC.

As far as I remember, some used to recommend renaming or removing recover.exe to prevent accidental damage.


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Subject: RE: Tech: SD card recovery programmes
From: JohnInKansas
Date: 17 Dec 11 - 09:36 PM

Jon -

Your suggestion makes sense if the drive is mangled so that the cluster addresses can't be identified in the FAT. A search for headers for known file types would give you a pretty good clue as to where a file starts.

The kind of recovery program I guess I was thinking about would be something like Norton Utilities (if anyone remembers that). Most lost files are the accidentally deleted ones, and the only thing a delete removes is the first byte (or first few), and the deletion only "loses" the first charactr of the file name. Any cluster that has "writing" in it, with a blank/null first byte is assumed to be a file, and poking a letter in makes it readable with normal Windows or Command/DOS functions.

CHKDSK (CheckDisk) in olden times (Since around DOS3.5?) could recover "lost clusters" and it put Filenames on them like what you mention, but left it up to you to decide how to put the fragments back together. Some fragments could be multiple clusters, but often you got lots of "just little bitty bits" of stuff. Features sort of "grew" with later DOS versions, and it's still in my Vista Command repertoire, although I haven't kept up with all the changes in how the newer versions work.

RECOVER is one I don't recall using, but it is still in my Vista. The usual /? doesn't tell much about it. I just get "Check the Online Command Reference before using."

In older DOS, a FAT disk only had the address of the first cluster of the file, the 8+3 name, and possibly a few Attributes (the big 4 commonly known?) in the FAT or a Folder. Each cluster gave the address of the next cluster at its end, and to build even a DIR command the drive had to look at & read at least a cluster of each file somewhere on the disk to get enough to make even a DIR listing report. The fixed length of the zero sector where the FAT lived limited the number of files that could be in the root. Since each cluster was supposed to point back to the preceding one (often omitted) and forward to the next one, a "reconstruction" of at least part of a file could be made starting at a random place on the drive. You could start anywhere in the middle of a file and work both ways, but the "backward pointers" often were omitted so success was pretty marginal.

In an NTFS format it appears that the same info is written in the FAT or the Folder initially (The FAT of course has another new name that I don't recall); but the system is supposed to update the Folder (in background?) at the next opportunity, so that enough info is actually in the Table to do quite a lot without need to explore the whole disk. (It appears there are now more than 100 "Attributes" to be tracked, among other things, and they probably are recorded in the Folders once the "completion" is done?)

The NTFS FAT (or whatever) no longer has fixed length or location, and doesn't even have to be in "contiguous clusters" like before, so it's (theoretically?) a lot more flexible. I have some reservations about the claim that it's "more secure" with respect to data loss, but I'm not sufficiently informed to make good guesses.

The "background completion" is probably a reason for "The Device is Busy and Cannot be Disconnected Now. Try again later" when you try to unmount a USB drive after you've made a fairly large change to contents. (It seems like "a few GB" is big enough, but it's not consistent. I've had external USB drive "hung busy" for more than a day after moving a paltry few hundred GB, apparently for this reason.)

It would be expected (by fools like me?) that recovery methods that worked on older drives would still work with the new layout, with restrictions on direct hardware access being the biggest stumbler; but the new generation of users (even among the pro programmers?) doesn't seem to have much interest in how the junk actually works.

John


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Subject: RE: Tech: SD card recovery programmes
From: GUEST,Jon
Date: 17 Dec 11 - 09:59 PM

Your suggestion makes sense if the drive is mangled so that the cluster addresses can't be identified in the FAT. A search for headers for known file types would give you a pretty good clue as to where a file starts.

That's right John. It does not use the file system (FAT, etc.) so it stands a chance with a drive in a bad state.

A weakness though is that it is pretty (photorec indicates it can sometimes deal with some minor fragmentation) dependant on the file data being stored in contiguous blocks.

The kind of recovery program I guess I was thinking about would be something like Norton Utilities (if anyone remembers that).

Yes, I have used it but a long while ago...


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Subject: RE: Tech: SD card recovery programmes
From: GUEST,Jon
Date: 17 Dec 11 - 10:28 PM

It would be expected (by fools like me?) that recovery methods that worked on older drives would still work with the new layout, with restrictions on direct hardware access being the biggest stumbler; but the new generation of users (even among the pro programmers?) doesn't seem to have much interest in how the junk actually works.

I'd guess you would have to be a hardware (eg device driver) programmer or writing something very specialised to really want to go down to the hardware level.


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Subject: RE: Tech: SD card recovery programmes
From: JohnInKansas
Date: 17 Dec 11 - 10:35 PM

dependant on the file data being stored in contiguous blocks

I wonder what it would do on one of the old drives where we had to spend hours or days getting the interleave set right?

... or maybe Fooles Troupe and I are the only one's who ever used hardware that old?

(He may be still running it, from descriptions he's posted of his setup.)

John


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Subject: RE: Tech: SD card recovery programmes
From: GUEST,Jon
Date: 17 Dec 11 - 10:44 PM

getting the interleave set right?

... or maybe Fooles Troupe and I are the only one's who ever used hardware that old?


I don't know but I've certainly never done that.


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Subject: RE: Tech: SD card recovery programmes
From: JohnInKansas
Date: 18 Dec 11 - 02:18 AM

Back when nobody could afford an HD bigger than 30MB (and DOS couldn't read anything bigger than that), the disk controller built into the hard drive had very little memory, and the heads couldn't read/write as fast as the disk could run the bits past them. It was common to "interleave" the sectors so that as the disk spun the heads read or wrote every other sector (2:1 interleave) or every third sector (3:1 interleave) or some other combination.

A file that was in "logically consecutive" sectors might actually be in physically separated sectors splattered all over the physical disk.

By changing the "interleave" you could speed up the net passthrough for the drive by as much as 5x or 6x over the best you could do without "optimising" the interleave. (Or screw it up by a factor of 5x or more by doing it badly.)

Earliest drives that I made the tweak on mostly peaked at something like 3:1 - 5:1, although one really "wanted to be" at about 7:1, but improvements in the matchup between disk speed and controller capabilities (helped a lot by just a little kick in the internal memory* in the controller, and by much improved head types).

By the time the first 60MB - 90MB HDs were usable (for DOS/Windows), most of them optimized at 1:1 or at worst 2:1, or the manufacturers set a fixed interleave and blocked changes; and people sort of forgot about trying to tweak them.

* The internal memory isn't/wasn't really quite the same as the buffer memory quoted for newer drives, but had the same purpose of providing a cushion for differences in speed for parts of the system that didn't quite match up all the time.

John


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