App to quickly analyze audio loudness of several video files? Is there an app for OSX that lets you quickly analyze the loudness of a bunch of video files, shows you the peak and RMS loudness of each file in dBFS (I think dBTP and LUFS would be too much to ask for) and maybe even outputs everything into a log file? It should preferably be free, or cost only a few bucks.

No special format support needed. It's all just basic QuickTime compatible stuff.
ffmpeg, a free multi-platform command-line tool, can do this. 

Use the volumedetect and EBUR filters on each of the files

ffmpeg -i input.mov -af volumedetect,ebur128 -f null - 2&gt; input.log


This will produce a log file with the initial lines looking like this:

[Parsed_ebur128_1 @ 0000000002d42400] t: 12.7       M: -32.7 S: -32.7     I: -30.7 LUFS     LRA:   3.1 LU
[Parsed_ebur128_1 @ 0000000002d42400] t: 12.8       M: -33.2 S: -32.7     I: -30.8 LUFS     LRA:   3.1 LU
[Parsed_ebur128_1 @ 0000000002d42400] t: 12.9       M: -33.2 S: -32.7     I: -30.8 LUFS     LRA:   3.1 LU
[Parsed_ebur128_1 @ 0000000002d42400] t: 13         M: -34.3 S: -32.9     I: -30.8 LUFS     LRA:   3.1 LU
[Parsed_ebur128_1 @ 0000000002d42400] t: 13.1       M: -34.3 S: -32.9     I: -30.9 LUFS     LRA:   3.1 LU


and the final lines:

[Parsed_volumedetect_0 @ 00000000005db400] n_samples: 18700288
[Parsed_volumedetect_0 @ 00000000005db400] mean_volume: -31.5 dB
[Parsed_volumedetect_0 @ 00000000005db400] max_volume: -5.3 dB
[Parsed_volumedetect_0 @ 00000000005db400] histogram_5db: 22
[Parsed_volumedetect_0 @ 00000000005db400] histogram_6db: 32
[Parsed_volumedetect_0 @ 00000000005db400] histogram_7db: 250
[Parsed_volumedetect_0 @ 00000000005db400] histogram_8db: 470
[Parsed_volumedetect_0 @ 00000000005db400] histogram_9db: 816
[Parsed_volumedetect_0 @ 00000000005db400] histogram_10db: 936
[Parsed_volumedetect_0 @ 00000000005db400] histogram_11db: 1796
[Parsed_volumedetect_0 @ 00000000005db400] histogram_12db: 2632
[Parsed_volumedetect_0 @ 00000000005db400] histogram_13db: 4516
[Parsed_volumedetect_0 @ 00000000005db400] histogram_14db: 6028
[Parsed_volumedetect_0 @ 00000000005db400] histogram_15db: 8846
[Parsed_ebur128_1 @ 0000000002d42400] Summary:

  Integrated loudness:
    I:         -28.6 LUFS
    Threshold: -38.9 LUFS

  Loudness range:
    LRA:         9.0 LU
    Threshold: -49.0 LUFS
    LRA low:   -33.6 LUFS
    LRA high:  -24.6 LUFS


The mean_volume is the RMS value.

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