Case: i have two exactly the same images, shot with 5 seconds in between.
These two images are visually identical when viewed:
In their JPEG preview.
In Adobe ACR
In dcraw (tested v9.22, 9.24 and 9.25) with commands -T -w -W.

Then when i use dcraw_emu as:
dcraw_emu -T -w -W

Using exiftool on a .CR2 photo converted to DNG, the following tags can be seen in the printout.

AS_SHOT_NEUTRAL
Raw Data Unique ID

However, when unpacking an image captured from the same camera (Canon 7D), I cannot find that data in the libRaw.imgdata structure, despite reading through the sub-structure data several times when in debug mode. I have found almost everything else needed.

I also scanned the documentation.

Any help wold be welcomed.

Thanks. Great library.

Hello,

I'm currently working on a scientific code that performs correlations to assess displacements between pairs of RAW images. I say that the RAW images come from a PhaseOne IQ180 because it may be the cause of my problem: the demosaicing seems not be accelerated with OpenMP.

Hi!
Is it straightforward to extract/build a RAW histogram (as a bitmap or even just as an array of values) from/using LibRAW?
I have a license for RawDigger and I'm using it for producing the histogram charts but I want to integrate this functionality into another application.
Thanks!
Assaf

p.s. I hope I'm posting in the right forum.

Hi,

I'm having a problem when trying to set up a gamma curve to use when processing data from .CR2 file.

The result is always the same (doesn't matter the values i set up).

Here's what my code looks like (pseudocode):

Rawprocessor;
Rawprocessor.openfile(file);
Rawprocessor.unpack();
Rawprocessor.imgdata.params.output_bps = 16;
 
Rawprocessor.imgdata.params.gamm[0] = 1.;
Rawprocessor.imgdata.params.gamm[1] = 1.;
 
Rawprocessor.dcraw_process();