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Just downloaded a big mkv file which is more than 20GB. It took me several days to finish the downloading. But, how to check whether the download has been completed, or it was just aborted halfway? I have this question, because for a mkv file, mplayer can still play it until the point it is broken.

Any utility in ubuntu for such kind of checks?

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    Do you have a hash or checksum (i.e. MD5/SHA1/CRC32/etc) of the MKV file in question? If you have, you can use the corresponding md5sum/sha1sum/crc32/etc to see if the hash or checksum match. – yjwong Nov 15 '13 at 18:52
  • @yjwong: Alas, I don't have such info, :-( – Qiang Xu Nov 15 '13 at 19:01
  • The question is how did you download it? Using a torrent client? – Hinklo Nov 15 '13 at 22:02
  • @Hinklo: No, just http protocol download, took me around several days to finish. Lucky the connection didn't break in the process. – Qiang Xu Nov 19 '13 at 21:51
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    Just check the exact size of the file you have with the size of the file you meant to download in the first place – Hinklo Nov 20 '13 at 9:16
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As you do not have checksum info for the file (CRC32, MD5, SHA-1, SHA-256, etc), you could try to validate the Mastroska format itself.

mkvalidator is a simple command line tool to verify Matroska and WebM files for spec conformance. It checks the various bogus or missing key elements against the EBML DocType version of the file and reports the errors/warnings in the command line.

To use:

mkvalidator --details your-big-mkv-file.mkv

However, mkvalidator could only validate the structure of the Mastroska container, not the "payload" (i.e. A/V data) in it. To validate the data portion, you still need a decoder to see if it decodes correctly. From https://superuser.com/a/100290 :

ffmpeg -v error -i file.avi -f null - 2>error.log

This command uses ffmpeg to read in the mkv file and tries to decode it frame by frame. Any errors found in the decoding process will be recorded in error.log file.

2

The matroska validation tool works great for checking the integrity of the container. Here is a recursive wrapper script that I wrote in python that I use for large libraries. https://github.com/1010dvpt/mkv-validator

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    That seems to be a script for Windows. This is a Ubuntu site. Am I missing something? – Gabriel Mar 31 '17 at 1:00
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    Tweak it to meet your needs? – Max Burns Dec 18 '18 at 8:36

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