LibRaw technical support

Stable LibRaw versions: technical support, errors, API questions

ImageMagick signatures are different when using 0.20.2 vs 0.21.1

Submitted by hughbiquitous on

I'm trying to do duplicate detection in my photo library and I was experimenting with using ImageMagick's identify -verbose tool to get a signature (SHA256 hash) of the pixel data.

A problem arose when I ran it on my Mac, which used the Homebrew distribution of LibRaw (the latest; 0.21.1) but I was getting mismatches on my Ubuntu 22.04 machine (which gets 0.20.2 of LibRaw). Once I built 0.21.1 on the Linux machine, the signatures were identical as expected, so I don't think it's an ImageMagick issue.

Forums: 

Samsung SRW

Submitted by lberger on

Hi,

I tested libraw with database from rawsample.ch. test means read and idsplay image. Good new all images (except one) are readable and can be display : Great works

Image with problem is http://www.rawsamples.ch/raws/samsung/RAW_SAMSUNG_NX500N_12BIT.SRW
may be file is dammaged I don't know

simple_dcraw.exe RAW_SAMSUNG_NX500N_12BIT.SRW
Cannot unpack RAW_SAMSUNG_NX500N_12BIT.SRW: Input/output error

Forums: 

File signature

Submitted by lberger on

Hi,
In opencv file image format (https://github.com/opencv/opencv/blob/4.x/modules/imgcodecs/src/loadsave...) are identified using file signature as a char array. A decoder is found using this signature tiff bmp jepg webp....

I found a method LibRaw::identify() but it is protected and need a file pointer.

Is there is a way to give a char array to check if file is readable using libraw?

Forums: 

Fujifilm GFX100S - Full Frame Crop Size

Submitted by Potch on

Hello,

I was trying to decode some full frame crop samples from Fujifilm GFX100S and something seemed off in the sizes.

I noticed that the imgdata.sizes.width was being calculated to be 9550, well the libraw_raw_inset_crop[0].cwidth comes to 9552, with from what I can tell 9552 is the intended width for these images.

I feel like the width shouldn't be shorter than the intended crop? Or should I not be comparing this crop against the imgdata.sizes.width and should be using it against the imgdata.sizes.raw_width?

Cheers

Forums: 

libraw-0.21.1\libraw\libraw_datastream.h(183) : error C3861: 'data': identifier not found

Submitted by JacksBack on

Hello,

I compiled the new LibRaw 0.21.1 as a Windows DLL - it worked perfectly as a 64-bit DLL, using the 2019 edition of Visual Studio.

I would also like to compile a 32-bit DLL using an older edition of Visual Studio, that works with Windows XP. When I do this, I get lots of these errors:

libraw-0.21.1\libraw\libraw_datastream.h(183) : error C3861: 'data': identifier not found

and

Forums: 

LibRaw 0.21.1 and RawSpeed v3

Submitted by Kuro on

I followed the instructions on downloading a specific commit of rawspeed from DarkTable and I applied the 4 patches (actually, patch 01. is not needed as it is already in the rawspeed source code).

I was able to compile RawSpeed 3 successfully.

But when I enabled RawSpeed 3 support in the Makefile.dist of LibRaw and make the correct reference to the RawSpeed3 directory, LibRaw would compile but with the following linker errors:

Forums: 

Color Information - Documentation

Submitted by SteveR on

Hi Alex:

In the Structure "libraw_colordata_t: Color Information", there are two arrays:-
float rgb_cam[3][4], described as "Camera to sRGB conversion matrix", and
float cmatrix[3][4], described as "Camera color data read from RAW file (if any)".

Could you advise me on the various properties contained within these arrays, or which source file(s) describes these arrays?

Thanks

Steve

Forums: 

Pages

Subscribe to RSS - LibRaw technical support