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-   -   EX1 .bim file and MPEG-7 metadata (https://www.dvinfo.net/forum/sony-xdcam-ex-pro-handhelds/475367-ex1-bim-file-mpeg-7-metadata.html)

Tito Sciortino March 22nd, 2010 05:29 PM

EX1 .bim file and MPEG-7 metadata
 
Hello all,
I've looked around but don't see anything so thought I'd post.

Not too long ago I was shooting some exposure tests with my EX1 and for some reason had assumed that in XDCAM Transfer I would be able to see the meta data for each take (exposure, WB setting, zoom, etc.), maybe because I had been lulled into a sense of complacency by the still photo metadata on my DSLR.

I was disappointed to find that I was mistaken and started looking around for where the data might be. I think it was Doug Jensen who somewhere mentioned that Sony engineers had told him that the metadata was already being collected on the EX cameras, but as yet not being used for anything. And the specs for the new PMW-350 say that the metadata is collected for use with future utilities.

Some more searching showed that .bim files are associated with MPEG-7, which if I understand correctly is a metadata protocol.

So I looked at what was in my .bim files (inside the BPAV's scene directories). Using an editor that allows me to read the hexadecimal data in binary files (on the mac I'm using HexEdit), I was able to see that some of this metadata is in fact there. Gain, for example, is stored as a one-byte number with 0db being stored as 128 (0x80), and the actual gain numbers as x - 128. So -3db is stored as 125 (125 - 128 = -3, or in hex, 7D - 80). WB is also there as just the temperature setting (my 7000K was stored as 6984 (0xIB48) and 5600K as 5599 (0x15DF). F-stop and zoom are also there, but I haven't been able to make sense of the encoding yet. It looks like there's approximately two data lines for each 1080/30p frame I shot.

My approach in figuring this out was to make a table of all combinations of two settings each of F-stop (f1.9 and closed), zoom (full wide, full tele), gain (0, -3), and WB (7000K and 5600K). This comes to 16 combinations. Then I shot a few seconds (with the lens cap on for convenience) at each setting, pulled from each .bim file the first 150-or-so characters of the first frame data line (maybe the third line of each file?), and pasted them all into a text editor so I could look at 16 lines of data (one for each combination of settings) right next to each other. The setting patterns pretty much jump right out.

Anyway, there's enough here to get any hobbyists out there started, but I was wondering if anyone else has looked at this yet and maybe has put together a little utility to read the .bim files and display the data? Especially on a mac?

Thanks,
Tito

Paul Kellett March 22nd, 2010 06:03 PM

Are you talking about the information displayed in clip browser ?

Paul.

Tito Sciortino March 22nd, 2010 06:09 PM

Paul,
I don't think so, unless there's something I'm missing in Clip Browser. It looks like it just shows more or less, date/time, duration, audio and video format, but not specific camera setting for the clip (like f-stop, white balance, zoom setting).

Is there some way in Clip Browser to get that detail that I'm just not seeing? (I hope so!)
-Tito

Victor Matos March 22nd, 2010 06:40 PM

In the browser, double click on the desired clip, look under the acquisition tab. There's some of that information there.

Tito Sciortino March 22nd, 2010 07:52 PM

Victor,
Thanks. I just got version 2.6 and under the Acquisition tab, I see what I was hoping for.
-Tito

Marty Welk March 22nd, 2010 09:20 PM

and here i thought he was 2 days away from building a better clip browser :-)


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