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Sharing the Wes

25 Aug 2007

Musikindustrin förändras, om det råder det ju knappast några tvivel om. En del av aktörerna gör sitt bästa stanna kvar i gamla strukturer, och motarbeta förändring. Men inte alla.

"Sharing the Wes" är John Wesleys koncept för att anpassa sig till hur verkligheten ser ut. Konceptet är egentligen mycket enkelt: all musik finns tillgänglig som gratis mp3-nedladdning (i rätt hög kvalitet; 160kbps) från hans sida på MySpace. Bara att tanka hem och lyssna. Är det så att man vill ha musiken i högre kvalitet, så finns fortfarande CD-skivor att köpa. Vill man inte köpa CD-skivor, så har han ett PayPal-konto, så att man helt sonika kan donera den summa pengar som man tycker att han förtjänar. Det är ju trots allt inte gratis att göra musik.

Jag gillar idén, och hoppas att det kommer att fungera för honom.

Exiftool

18 Aug 2007

During the image recovery process described in the previous post, some of the retrieved images got funny names. Usually, my camera (a Canon EOS 10D) produces two files per photo when using the RAW mode. The names of these files are in the form CRW_0123.CRW and CRW_0123.THM. The .CRW file contains the actual image data, and the THM file is a sidecar file containing a JPG thumbnail of the photo, along with some EXIF data. During the recovery operation I got a number of files named like this:

V0000001.CRW
V0000002.THM
V0000003.CRW
V0000004.THM
...and so on.

Since every second file was CRW and every other file was THM, I figured that the recovery software just didn't manage to find the file names of these files and just gave them a sequence number instead. The file formats, however, were kept intact.

I wanted to restore the original file names, in order to see if there were any gaps in the file name sequence, which would indicate that there were images that were not restored. Enter EXIFTool. This is a most powerful tool when it comes to anything related to exif data.

Using exiftool, I inspected the exif data of a couple of CRW and THM files and it turned out my thoughts were correct; these seemed to be file pairs belonging together. One of the exif fields is named "File Number", looking like this: 322-2254. The corresponding name of a CRW file would be CRW_2254.CRW. So, all that was needed was to extract this number from each file and renaming the file using that number. The following commands took me a bit on the way:

exiftool.exe "-filename<${filenumber}.CRW" *.CRW
exiftool.exe "-filename<${filenumber}.THM" *.THM

Now I had a sequence of files named like this instead:

322-2254.CRW
322-2254.THM
322-2255.CRW
322-2255.THM
...and so on.

To completely restore the filenames, a simple rename command was used:

ren ????????.* CRW_????.*

There, filenames restored. When copied into the archive I found that only two files were missing, and those were actually deleted by me immediately after the files were restored (they were simply too bad).

I am quite sure that there is a way to do this so that all files could be handled at the same time, instead of running it once per file extension, and that would also give the files the correct names from the start, but it was not really time consuming so I decided not to dive into that at this time. If you happen to know the way to do this, feel free to post a comment.

Our family is a bit scattered around the world. During the last week we have had some relatives visiting, who currently have their residences in Germany, Hungary and Australia. Needless to say, it's not often that all meet in the same spot at the same time (unless Skype is involved). So, of course there were some photos taken of the full group. Memory cards were filled, and emptied into the computer. Coming home after work one day, I was told that the card in the camera needed to be emptied. Said and done. When I got the card-reader there was a card already sitting in there. I assumed that it had been left there when I emptied it last time (I usually do not put the card into a reader unless I am emptying it). So, I took it out, put the other card in the reader, copied the files to the computer, then formatted both cards in the camera. Just to realize that the first card had NOT been emptied, and of course it contained the most important family pictures from the week; the rather rare group photo... Fortunately, no new pictures had been taken after formatting, so the card was removed from the camera and rescue attempts ensued.

First I tried SanDisk Rescue Pro, which came bundled with a Compact Flash card a couple of years ago. It did find a good number of CRW-files on the card, but most were corrupted and could not be used by the RAW conversion software that I tried with it. It also provided the possibility to dump the contents of the card as a disk image on my hard drive. Then I started searching for various free-ware and cheap recovery software. A number of them were tried, with various results. But one stood out above the others, since it was a lot faster, and also managed to locate almost all lost files. The $35 that I paid for having a full working copy of PhotoRescue were truly very well spent.

It provides the basic set of operations that you could need in situations like these; backup a card to a disk image and recover files from either a card or a disk image. The recovery can be done in two different ways; either the quick recovery, or the advanced. The difference is that the quick recovery will try to figure out details about the card, while advanced recover lets you specify details about how the recovery should be performed.

To put is short; buying a license for this piece of software is money well spent.