A few days ago, I was recording a video with my Panasonic SD90 camcorder on a small tripod, in precarious balance on a small surface (
don't do dat) ; at some point it fell, and then a message appeared on the screen saying “Control data error has been detected” (actually it was in french, but from what I could find doing a research with the most likely keywords this seems to be the exact formulation of the error message in english with that range of devices – with the french wording I only found three results, two of them being PDF manuals for Panasonic camcorders of different models – and even in english all I could find were threads about hardware failures or user errors – like deleting video files from a computer – so nothing relevant to that particular issue). Then the message “Repairing” appeared. As it was taking too long and I was in a hurry to continue shooting, and as I couldn't stop the process, even by pressing the power-on / power-off button, I had to remove the battery, then put another SD card, figuring that I would try to figure it out later on. (Besides, I have read when searching about this that the “repairing” process could completely delete a clip if it didn't manage to properly recognize it, which is quite scary.)
Then, yesterday, I first opened the problematic SD card on the computer, copied everything from it to a HDD as a safety measure, and examined the “STREAM” video folder : that clip I was shooting when the camera fell is there, named 00017.MTS (along with another short clip named 00016.MTS), and seems to be flawless all the way through, until the very moment when it fell (I can see a slow upward panning at the very end). But of course the metadata is missing, and the software HDWriter which I use to import videos from this camera doesn't recognize that clip. Then I put that memory card in the camcorder, hoping that it would simply resume the repairing process, but it didn't ; it didn't find a problem with the data structure either, it was ready to shoot. Then, hoping that I could force it to redo the repair, I started recording a new clip, then deliberately removed the memory card, then put it back in : it did display the same messages, and this time I let it finish the repair process, but it was finished very quickly anyway, and it only repaired the clip I had just taken (meaning that it added the correct AVCHD metadata), not the one I want to fix. And then, more puzzling : the camera in view mode now only recognizes that last clip, everything else seems to be gone, even the still pictures. However, if I access the card from the computer, I can still see the still pictures, and the three MTS clips (the two that were there earlier plus the new one). If I compare with the structure I backed up earlier with WinMerge, I can see these differences :
– a new 00018.CPI file in “BDMV\CLIPINF” (the other one being 00016.CPI corresponding to the first short clip, so there's no 00017.CPI corresponding to 00017.MTS),
– a new 00003.MPL file in “BDMV\PLAYLIST”,
– a new 00003.VPL file in “IISVPL”
– the THUMB.TDT and THUMB.TID files in “AVCHDTN” are different,
– the INDEX.BDM and MOVIEOBJ.BDM files in “BDMV” are different.
Then I restored the files from the backup when different, deleted the newly added files, which should have re-generated the structure of the AVCHD folder exactly as it was before I made those attempts – but then the device in view mode recognized no file at all. Now I'm at a loss...
Back to the main issue : is there a way to generate the missing metadata in a situation like this, either by forcing the camera to do so, or by using computer software ? Failing that, where could I find a description of each one of the relevant files, detailed enough so that I could try to generate the missing ones by editing the existing ones in order to properly import that clip ? Or is there nothing else I can do except copy the MTS file as-is and use it as-is for editing purposes ?
Thanks.