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    repairing corrupted jpg

    I have managed to recover jpg files from a memory card. The thumbnails show the complete image but the jpg files are missing some portion of the image.

    Does anyone know how I could restore the missing portion of the images in the jpg files? I was hoping that irfanview would provide a tool to acccomplish this but when I open the files in Irfanview I get the same results as with other photo editors.

    Thanks much in advance!!!
    Scott

    #2
    More info needed. Which application does 'The thumbnails show the complete image' ?
    'are missing some portion of the image'. Which portions ? The lower part ?
    Since your thumbnail view functions ok, maybe that's the moment to re-save the file again, before re-opening it.
    0.6180339887
    Rest In Peace, Sam!

    Comment


      #3
      more info

      The thumbnails display fine primarily in Windows Explorer running on XPPro Sp2. It is the lower portion of the image in all cases. Images are opened with irfanView, MS paint and are missing image areas. If I look at the thumbnails in irfanView the image areas are also missing as they are in the software. The corrupted area varies in size between images. Attached are 2 examples.

      scott

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        #4
        Is it possible that the thumbnails that you are seeing in Explorer may have been created before the images were corrupted? If Explorer is getting them from a "thumbs.db" file that was created earlier, what you see there has nothing to do with the actual images.
        Its: Belongs to "It"
        It's: Shortened form of "It is"
        ---------------------
        Lose: Fail to keep
        Loose: Not tight

        ---------------------
        Plurals do not require apostrophes

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          #5
          Good point
          0.6180339887
          Rest In Peace, Sam!

          Comment


            #6
            In the past I've been sifting this matter out, but came to the conclusion, that only the not-corrupted portion of such a file is to be saved. It's a pity, but these things often happen, particularly when downloading from the web.

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              #7
              These files were restored from a memory card that was taken with my daughters Canon camera using PC Inspector Smart Recovery. I was unable to see any files without using the above software. There are a few images that have a portion of one frame from one image as part of another image. In the film days you could get that by not advancing the film completely or not fully pulling the slide out of a 4x5 film carrier. I'm not sure when the db file gets created. Sam if you unzip the attached files and preview them in Windows explorer do you get the full thumbnail or just a portion? I've tried it on a few computers and get the same results, which is odd because there is no db when I just take these two files onto a different computer, is there?

              Thanks again for everyone's input.

              Comment


                #8
                I was unable to see any files without using the above software
                Why not ? Couldn't you look at the files on the memory card with just a file manager ?

                Sam if you unzip the attached files and preview them in Windows explorer do you get the full thumbnail or just a portion?
                I can't unzip them because I can't find any attachments in this topic so far.
                A note in advance, I'm running W2K and I refuse to preview something with exploder, because I don't use it.
                0.6180339887
                Rest In Peace, Sam!

                Comment


                  #9
                  Hi sballering,
                  I'm curious about your zip file too and I use XP-sp2. I've got several programs installed to view and edit images. So hopefully I can do something about them.

                  Comment


                    #10
                    update

                    Sam I can understand not using Windows Explorer not the browser. No when I looked at the SD card I saw two directories but there was no files I could see. Only after I ran the recovery software did I get anything from the SD card. There were also two movies on the SD card that I have not been able to recovery yet.

                    I attached a zip file with two jpg files that are missing part of the image but the thumbnail appears fine in Windows Explorer. I will try doing another attachment of the two files, appearently I did it incorrectly or if there's and email I could send them to I could do that.

                    Scott

                    convar24.jpg
                    convar6.jpg

                    Comment


                      #11
                      It's not important, but why you use 'unzip' and 'a zip' ? I just see two attached JPG files. Or is this in a manner of speaking ?
                      when I looked at the SD card I saw two directories but there was no files I could see.
                      Are you sure that your file view setting then did included 'hidden' (like 'thumbs.db') and 'system' files ?

                      I just checked the 2 files. They are definitely damaged. I've tried several kinds of thumbnail view, but all came of course with the same damaged images.
                      So I guess Matera could be right about the "thumbs.db" file.
                      This can be tested by making a dummy directory somewhere, and copy the two JPG files in it.
                      Then do a Thumbnail view in that folder with Exploder again..

                      These two images are typical examples of what can happen during a download, as Sjef mentioned.
                      Something goes wrong within the file, value-relations between pixel-sizes and End of File string.
                      That's why it's always the bottom part missing.
                      So I checked the normal EOF bytes in a JPG and it's FF D9. These values are not at the end of the two 'convars'..
                      Alas, adding or editing FF D9 at the end didn't help.

                      I don't know the structure of a "thumbs.db" file, but that one, still showing the correct images, is maybe the only bridge to the originals.
                      0.6180339887
                      Rest In Peace, Sam!

                      Comment


                        #12
                        Hi Scott,

                        Why did you need to recover files from your card? Did you format it or did you delete the images? Did you record new images after that? In that case I believe there is no hope to recover more than what you got. Older images have probably been (partly) overwritten or the FAT of your card has been corrupted.
                        Also, I believe that a recovery program makes its best but without guarantee; it's even possible that it has been confused and has itself overwritten parts of your images.

                        Laurent
                        Before you post ... fill in your OS and IV version in your profile.

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                          #13
                          Right on. I was wondering too. Why start with recovery in the first place ?
                          Or was this 'PC Inspector Smart Recovery' presenting itself as the only way to get files from the card ?
                          I agree with Laurent that your chance of getting the originals back is quite small. Especially if, as he states, more data activity has been taken place on the card after the moment of failure.
                          File recovery is a very delicate process, and rule one is (as I experienced lately with an accidental delete outside the bin) :
                          Stop doing anything on that medium or partition.
                          I know one file recovery app "File Scavenger" which can get quite 'deep', but also indicates what the chances of recovery are.
                          Unfortunately the light version has a limit of 64 KB.
                          0.6180339887
                          Rest In Peace, Sam!

                          Comment


                            #14
                            update

                            Thank you to all.

                            To answer some questions regarding ZIP, it is a file format used in some compression software to compress files into a smaller file. Tools like WINZIP or PKware and compression utilities. My first attempt at attaching a file did not work correctly so that is why I attached 2 jpg files.

                            My computer is set to show all files types. exe, dll and others and I have full administrator rights on my computer. I understand the files should have displayed but they did not. I am not sure if the FAT is corrupted or what but I cannot display the files when viewing the USB SD card reader as any Drive letter.

                            The beginning of the problem started when: My daughter was viewing her pictures on her camera and then her camera said that she needed to format the SD card and there were no files on the card. At that point I had her turn off the camera and I purchased a card reader so I could use my computer to get the files off the SD card. When I opened the drive for the SD card reader in Windows it showed two folders. I double click on the two folders and there were no files that Windows Explorer could or would display.

                            I installed the recovery software and ran the software. The recovery software recovered about 317 files. Most of these files are fine but there are about 10 files that seem to be corrupted. I am happy with getting back as many files as I did, but was asking if there is a way to recover the lost data in these 10 files since the thumbnails, when viewed in Windows Explorer “the file structure display tool” not “Browser” shows the Thumbnails correctly but the jpg files are missing some of the image.

                            If the answer is I cannot recover the missing data in these files even if the thumbnails show up correctly in Windows Explorer then fine. I was hopping since the thumbnail did display correctly there would be a way to recover from that file data.

                            The reason I attached the 2 jpg files was to address a question that was posted and see if the thumbnails would show up correctly on someone else’s computer, namely SAM’s computer and if they did maybe he could suggest a way to recovery the jpg files.

                            Comment


                              #15
                              Originally posted by sballering
                              My first attempt at attaching a file did not work correctly so that is why I attached 2 jpg files.
                              Very amusing by the way. After way back starting with DOS 4.0 on a XT, now somebody is so kind to explain to me what a ZIP is..
                              But serious. I must admit, that I have problems too with attempts to add some attachment to a post. I'm sure it is my fault, but I found the dialog quite fuzzy so far.

                              Thanks for the clear story concerning what happened before the recovery stage.
                              As you have read, the two jpg files didn't show up correctly on my computer. So definitely damaged.
                              But they have the original size. Not as thumbnail.
                              This was an accident. And accidents oftens causes damage. So a score of 10 to 317 is quite nice for a recovery.
                              But I fully understand your drive to get more out of it.

                              But even if you manage to recover from the correct thumbnail view, you'll get the picture back as a small stamp, not the original. If you see the thumbnail, it must be saved somewhere, in a temp-dir or in memory.

                              and then her camera said that she needed to format the SD card and there were no files on the card
                              This is a crucial moment.
                              'No files on the card' can mean that there indeed aren't any.
                              But it can also mean that they are deleted by some action. Then they are still there on the medium, but they are no longer in the index-list to show, and their space is declared free to use. Here a recovery tool can come into action.
                              But, very important, no other apps should be run, because maybe they will overwrite this 'free space' with something..
                              And the Windoze thumbnail viewer has the habit of creating a hidden file called 'thumbs.db' in the same dir as the pictures.
                              0.6180339887
                              Rest In Peace, Sam!

                              Comment

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