Recent comments

Reply to: LibRaw 0.19.2-Release   4 days 12 hours ago

Current public snapshot supports Nikon Z6 and Z7, sorry these cameras was missed from release announce
https://www.libraw.org/news/libraw-snapshot-201903

Reply to: LibRaw 0.19.2-Release   5 days 1 hour ago

When the Nikon z6 z7 release the firmware?

Reply to: LibRaw 0.19 supported cameras   2 weeks 4 days ago

Sony A7-3 is supported in current snapshot: https://www.libraw.org/news/libraw-snapshot-201903

EOS-R support is expected in next snapshot/release, whatever comes first.

Reply to: LibRaw 0.19 supported cameras   2 weeks 4 days ago

Not sure how the compatibility works, but I own a Sony A7 III and a Canon EOS R. If I can scrape any data to help add each of those to the support list, I'd be glad to try.

Reply to: Get Pixel dimensions   1 month 5 days ago

Mhhh ok.
So I will keep my estimation using sizes.width I guess.

Reply to: Get Pixel dimensions   1 month 5 days ago

The only way to get the accurate number for that is to look it up in the sensor data sheet. Raw file may contain virtual pixels, and may not contain all the physical pixels.

Reply to: Get Pixel dimensions   1 month 5 days ago

In astrophotography, Pixel size is a value often needed ;).

Reply to: Get Pixel dimensions   1 month 5 days ago

I don't see any practical sense in getting the exact pixel pitch value. Any approximated value is good enough

Reply to: Get Pixel dimensions   1 month 5 days ago

OK, Thanks for the explanation.
If you would write the formula to compute (estimate) the pixel pitch then, would you use raw_width or width ?
raw_width seems to be more the good one but for canon it gives result pretty far from the vendor value:

pitch = 22.3/6288 * 1000 = 3.55 (while it is given to be 3.7)
At the opposite, for the Sony it gives better result.

Not that easy :).

Reply to: Get Pixel dimensions   1 month 5 days ago

Single pixel size error in raw_width will result in distorted picture (like synchro loss on old analog TV), so raw_width/raw_height values are indeed right in LibRaw.

Visible (non masked) area is a matter of taste: LibRaw specifies 'as much as possible' (full visible area), while in-camera JPEGs (and, so, vendor advertized image size) may be slightly less than full area.

Reply to: Get Pixel dimensions   1 month 5 days ago

I would expect that the Sensor resolution width would match the raw_width, or the width value.
But I may be wrong.

For example
For Canon EOS 200D:
Sensor resolution width = 6026 pixels
Libraw:
width: 6022
raw_width: 6288

For Sony Alpha 7S:
Sensor resolution width = 4278 pixels
Libraw:
width: 4256
raw_width: 4288

Reply to: Get Pixel dimensions   1 month 5 days ago

What accuracy did you expect?

Reply to: Get Pixel dimensions   1 month 5 days ago

The resolution value, given in the link I gave you don't match with any field of libraw: width, iwidth nor raw_width.

Reply to: Get Pixel dimensions   1 month 5 days ago

Where I can find the explanation of the field ? ==1 (Canon APS-C?), == 2 (FF ?)

EDIT: I found it.
enum LibRaw_camera_formats
{
LIBRAW_FORMAT_APSC = 1,
LIBRAW_FORMAT_FF = 2,
LIBRAW_FORMAT_MF = 3,
LIBRAW_FORMAT_APSH = 4,
LIBRAW_FORMAT_1INCH = 5,
LIBRAW_FORMAT_FT = 8
};

Reply to: Get Pixel dimensions   1 month 5 days ago

Thanks Alex.
I will try this way.

Reply to: Get Pixel dimensions   1 month 5 days ago

For many (but not all) cameras LibRaw parses sensor physical size type (full frame, APS-C) into imgdata.lens.makernotes.CameraFormat

You may use this field and pixel dimensions (raw_width, raw_height) to estimate pixel pitch.

Reply to: Get Pixel dimensions   1 month 5 days ago

I don't think so, I would like the pixel pitch:
https://www.digicamdb.com/specs/canon_eos-200d/

Reply to: Get Pixel dimensions   1 month 6 days ago

imgdata.sizes.raw_width/raw_height are not enough?

Reply to: Is there a way to know it DSLR is 12 or 14bits   1 month 2 weeks ago

Thanks a lot, that was what I was looking for.
Many thanks

Reply to: Is there a way to know it DSLR is 12 or 14bits   1 month 2 weeks ago

imgdata.color.maximum variable holds maximum data range (this value is not black-level-subtracted)

Reply to: Is there a way to know it DSLR is 12 or 14bits   1 month 2 weeks ago

OK, sorry for this dummy question indeed.
So my question is now how libraw know the constant factor to apply to normalize to 16bits ?
Sorry if it is a dummy question again.

Reply to: Is there a way to know it DSLR is 12 or 14bits   1 month 2 weeks ago

Could you please explain 12 vs 14 bit difference for Sony cRAW format:

1) Data stored in 8-bit per pixel overall (16-pixel blocks, 11-bit base value, 7-bit deltas)
2) After decompression: 11 bit non-linear data
3) After linearization curve applied: ??bit data with data range 0...~17000

File format is the same for 12-bit ADC cameras (e.g. A700), real 14-bit ADC (e.g. Sony A7r) and 14-bit ADC in 12-bit mode (A7R in electronic shutter mode).

Reply to: Edit EXIF data using external library   1 month 2 weeks ago
Is this possible with the current code?

I do not know. Please try and let us know

is recommended to use LibRaw::open_buffer() to open file or better to use directly LibRaw::open_datastream()
Both ways should work.

Reply to: LibRaw (dcraw?) orientation tag wrong?   1 month 3 weeks ago

Thank you very much Alex ;-) !

Reply to: LibRaw (dcraw?) orientation tag wrong?   1 month 3 weeks ago

And followup:

dcraw_emu/dcraw.c also accepts user_flip in degrees (e.g. 90, 270, or -90), to handle this too, add these lines before snippet in previous message:

if (flip > 89 || flip < -89)
{
flip = (flip + 720) % 360;
switch (flip)
{
case 90: return 6;
case 180: return 3;
case 270: return 8;
default: return 1;
}
}

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