From 14e66c13db5f0c54a844ef85806d285b5e5407ea Mon Sep 17 00:00:00 2001 From: Ashley Blewer Date: Fri, 9 Nov 2018 08:46:56 -0500 Subject: [PATCH 1/2] Add command for getting checksum from stream --- index.html | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/index.html b/index.html index bc5ddb4..48e90bf 100644 --- a/index.html +++ b/index.html @@ -1861,6 +1861,25 @@ + + + +
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Get checksum for video/audio stream

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ffmpeg -loglevel error -i input_file -map 0:v:0 -f hash -hash md5 -

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This script will perform a fixity check on a specified audio or video stream of the file, useful for checking that the content within a video has not changed even if the container format has changed.

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ffmpeg
starts the command
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-loglevel error
sets the verbosity of logging to show all errors
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-i input_file
path, name and extension of the input file
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-map 0:v:0
designated the first video stream as the stream on which to perform this hash generation operation. -map 0 can be used to run the operation on all streams.
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-f hash -hash md5
produce a checksum hash, and set the hash algorithm to md5. See the official documentation on hash for other algorithms.
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-
FFmpeg syntax requires a specified output, and - is just a place holder. No file is actually created.
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+ + From e431fbb3c5bdeb488f8406672a84bf1c85a07330 Mon Sep 17 00:00:00 2001 From: Ashley Blewer Date: Fri, 9 Nov 2018 08:47:18 -0500 Subject: [PATCH 2/2] Add space between Note and the note in Create stream md5s --- index.html | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/index.html b/index.html index 48e90bf..7ee8e4c 100644 --- a/index.html +++ b/index.html @@ -1856,7 +1856,7 @@
-c:a copy
ensures that FFmpeg will not transcode the audio to a different codec before generating the MD5 (by default FFmpeg will use 16 bit PCM for audio MD5s).
output_file_2
is the output file for the audio stream MD5.
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Note:The MD5s generated by running this command on WAV files are compatible with those embedded by the BWF MetaEdit tool and can be compared.

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Note: The MD5s generated by running this command on WAV files are compatible with those embedded by the BWF MetaEdit tool and can be compared.