user4943: In BDAV's M2TS there are .clpi files, in AVCHD the same files are labeled as .CPI. As i understand, some sort of metadata is written into these files. The question is twofold:

What metadata exists in these files? (both 'by the standard' and 'de facto', if there are differences)
Are there any free/libre/open-source software tools that are able to extract this metadata from them?

An example of such a file is here.

user10468: As Professor Sparkles has correctly pointed out (I've just checked and confirm) — the MediaInfo tool can extract some metadata from these files. Here is a sample output from one of mine:
General
Complete name                            : /Volumes/CAM_SD/PRIVATE/AVCHD/BDMV/CLIPINF/00119.CPI
Format                                   : Blu-ray Clip info
File size                                : 502 Bytes

Video
ID                                       : 4113 (0x1011)
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Width                                    : 1 920 pixels
Height                                   : 1 080 pixels
Display aspect ratio                     : 16:9
Frame rate                               : 50.000 fps

Audio
ID                                       : 4352 (0x1100)
Format                                   : AC-3
Format/Info                              : Audio Coding 3
Channel(s)                               : 2 channels
Sampling rate                            : 48.0 KHz
Compression mode                         : Lossy
Language                                 : English

Text
ID                                       : 4608 (0x1200)
Format                                   : PGS
Language                                 : English

(But note that it can output more details in the --full mode.)
Also, it may be helpful to note that the AVCHD standard is proprietary and its spec is not publicly available. Attempts to reverse-engineer its components exist, and one of them is in this forum thread (from 2008): http://forum.doom9.org/showthread.php?t=141361

4943: <p>In BDAV's M2TS there are .clpi files, in AVCHD the same files are labeled as .CPI. As i understand, some sort of metadata is written into these files. The question is twofold:</p>

<ol>
<li>What metadata exists in these files? (both 'by the standard' and 'de facto', if there are differences)</li>
<li>Are there any free/libre/open-source software tools that are able to extract this metadata from them?</li>
</ol>

<p>An example of such a file is <a href="https://dl.dropboxusercontent.com/u/1033657/00074.CPI" rel="nofollow">here</a>.</p>
 10468: <p>As <a href="https://video.stackexchange.com/users/3295/professor-sparkles">Professor Sparkles</a> has correctly pointed out (I've just checked and confirm) — the <a href="https://mediaarea.net/en/MediaInfo" rel="nofollow noreferrer">MediaInfo</a> tool can extract some metadata from these files. Here is a sample output from one of mine:</p>

<pre><code>General
Complete name                            : /Volumes/CAM_SD/PRIVATE/AVCHD/BDMV/CLIPINF/00119.CPI
Format                                   : Blu-ray Clip info
File size                                : 502 Bytes

Video
ID                                       : 4113 (0x1011)
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Width                                    : 1 920 pixels
Height                                   : 1 080 pixels
Display aspect ratio                     : 16:9
Frame rate                               : 50.000 fps

Audio
ID                                       : 4352 (0x1100)
Format                                   : AC-3
Format/Info                              : Audio Coding 3
Channel(s)                               : 2 channels
Sampling rate                            : 48.0 KHz
Compression mode                         : Lossy
Language                                 : English

Text
ID                                       : 4608 (0x1200)
Format                                   : PGS
Language                                 : English
</code></pre>

<p>(But note that it can output more details in the --full mode.)</p>

<p>Also, it may be helpful to note that the AVCHD standard is proprietary and its spec is not publicly available. Attempts to reverse-engineer its components exist, and one of them is in this forum thread (from 2008): <a href="http://forum.doom9.org/showthread.php?t=141361" rel="nofollow noreferrer">http://forum.doom9.org/showthread.php?t=141361</a></p>
