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Context: Last night I was downloading a video from HTTP source (Megaupload to be precise) with DownThemAll! manager. Went to sleep, came back this morning and found the PC had shutdown during the night. Reopening the manager showed that file was no longer in the queue, so I was pretty sure it's completed.

Problem: Tried to play it and it's got places in the video that stop playing. Had to restart and skip the parts etc. Hassle!

Solution? What I usually do: download a .torrent file and check local data, and thereby download the missing chunks.

Problem again: Oh, I see. The file is old and the provider group have a new version, so they don't offer it any more. No seeders. Did find that there are missing chunks though (from the graphical view in KTorrent).

So what to do? The most logical course of action, if it's at all possible, would be to:

  1. Find out the exact chunk numbers that are missing from some torrent program.

  2. From that, calculate the byte ranges that are the problem (easy; from the number of chunks in KTorrent, I see that every chunk should be 512 KB).

  3. Re-download those byte ranges.

  4. Merge them into the file.

For 1, no clue - some command-line option in KTorrent/Transmission/some other program? For 3, I hear there's this thing called curl? Can it handle 4 too?

Just a note: re-download is not an option. Got a bandwidth cap. >_>

share|improve this question
I dont know anything about Ktorrent, but does it zero the byte ranges, or does it link all chucks at the end? if it zeros the range, then you can check for that. – soandos Jul 13 '11 at 18:09
Use JDownloader and you won't have this problem in the future (it supports downloading resuming and all that jazz). What I don't understand is how you have missing chunks in the middle of the file, when most HTTP downloads start from the beginning and finish at the end... – Breakthrough Jul 13 '11 at 18:12
@soandoes: Please clarify? @Breakthrough:Well, DownThemAll does download in chunks if possible after all (I have configured it to be 5). I assume the start or end of soe of the chunks weren't downloaded properly... – Deep-B Jul 13 '11 at 18:35
@Deep-B, thanks for clarifying that. Please do look into JDownloader for your future download needs, however, as it may help mitigate the risks of corrupted/incomplete downloads in the future. – Breakthrough Jul 13 '11 at 18:38
Find a source for the video and download the entire file again. – Moab Jul 13 '11 at 21:51

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