ExifTool Forum

ExifTool => Newbies => Topic started by: BangkokPhoto on March 21, 2017, 02:42:52 PM

Title: Panasonic RW2 IR Color Channel Swap
Post by: BangkokPhoto on March 21, 2017, 02:42:52 PM
I had a Panasonic DMC-GF1 converted to IR. This conversion requires the red and blue color channels swapped in post with GIMP; the workflow is very time consuming. Is there a way to swap color channels in the RW2 files in exiftool.

In the beginning I would shoot JPG; and have never found a way to swap color channels for JPEGs; could ExifTool swap color channels in JPEG files?
Title: Re: Panasonic RW2 IR Color Channel Swap
Post by: StarGeek on March 21, 2017, 02:50:41 PM
No.  Exiftool only processes image metadata, not the image data itself.

But it looks like ImageMagick (https://www.imagemagick.org) will do it.  See this thread (http://www.imagemagick.org/discourse-server/viewtopic.php?t=21846).
Title: Re: Panasonic RW2 IR Color Channel Swap
Post by: BangkokPhoto on March 21, 2017, 02:59:13 PM
the RW2 files contain color-channel in the EXIF data.
Title: Re: Panasonic RW2 IR Color Channel Swap
Post by: Phil Harvey on March 22, 2017, 12:25:53 PM
I don't know of any RW2 metadata that ExifTool can write which would allow you to do this.

- Phil
Title: Re: Panasonic RW2 IR Color Channel Swap
Post by: BangkokPhoto on March 28, 2017, 05:26:37 AM
I was seeing:
0x0011   RedBalance   int16u   (found in Digilux 2 RAW images) **** (Also in the GF1)
0x0012   BlueBalance   int16u

and thinking I could swap them.
Title: Re: Panasonic RW2 IR Color Channel Swap
Post by: Phil Harvey on March 28, 2017, 08:02:00 AM
That wouldn't work, and would just change the brightness of red and blue without swapping them.

You would need to change the CFA pattern somehow, but I don't know how to do this for RAF images.

- Phil
Title: Re: Panasonic RW2 IR Color Channel Swap
Post by: reisschuessel on August 16, 2017, 05:27:08 PM
Quote from: Phil Harvey on March 28, 2017, 08:02:00 AM
You would need to change the CFA pattern somehow, but I don't know how to do this for RAF images.
As i was experimenting with changing the CFA pattern of some RAW files of different manufacturers i was wondering about this too.
It turns out that if converting a Panasonic RAW to DNG you get the "CFA Pattern 2" which can then be used to swap the channels.
I checked with files from an LX-3 and GF5.

Maybe this is of interest for the thread opener or someone else?

-Niels