Skip to content

Latest commit

 

History

History
58 lines (34 loc) · 2.77 KB

databases.md

File metadata and controls

58 lines (34 loc) · 2.77 KB
Raw

How to generate cr2_database.txt and dng_info.txt for new cameras samples ?

cr2_database.txt

This CSV table lists Jpeg and Image properties extracted from each CR2 files. What is required is one CR2 sample for each camera and each data type: raw, sraw and mraw.

Imaging Resource is a great site to get CR2 samples, but do not provide YUV (mraw and sraw) files.

Then samples_list_rggb.txt and samples_list_yuv.txt must be updated to handles new files, then the cr2_database.sh script can be used.

craw2tool -m is used to extract model Jpeg and images properties.

$ src/craw2tool.exe -m  pics/80DhSLI00100NR2D.CR2
0x80000350, Canon EOS 80D, 14, 3144, 4056, 2, 1, 1, 1, 3144, 3144, 6288, 4056, 276, 46, 6275, 4045, 0, 0, 0, 0, 6000, 4000, 0

$ src/craw2tool.exe -m  pics/IMG_0590_mraw.CR2
0x80000287, Canon EOS 60D, 15, 3888, 2592, 3, 2, 2, 8, 1296, 1296, 3888, 2592, 0, 0, 3887, 2591, 0, 0, 0, 0, 3888, 2592, 0

$ src/craw2tool.exe -m  pics/IMG_0596_sraw.CR2
0x80000287, Canon EOS 60D, 15, 2592, 1728, 3, 2, 1, 5, 864, 864, 2592, 1728, 0, 0, 2591, 1727, 0, 0, 0, 0, 2592, 1728, 0

Format is : modelId, modelName, jpeg_bits, jpeg_wide, jpeg_high, jpeg_comp, slices[0], slices[1], slices[2], jpeg_hsf, jpeg_vsf, sensorLeftBorder, sensorTopBorder, sensorBottomBorder, SensorRightBorder, blackMaskLeftBorder, blackMasktopBorder,blackMaskBottomBorder,blackMaskRightBorder, imageWidth*, imageHeight*, vShift*

Notes that images dimensions and RGGB borders are automatically computed (noted *) !

vShift==1 means that the first line of sensor data is G2 B,G2 B, ... and not R G1, R G1, ... which seems a bug in Digic 4.

to generate the database:

./cr2_database.sh >cr2_database.txt

some warnings are displayed, no problem.

dng_info.txt

This database mainly contains color calibration data, like the adobe_coeff() table in dcraw.

The trick is to use DNG Converter from Adobe to convert CR2 files and the extract these information from the generated dng file.

BlackLevel (0xc61a), WhiteLevel (0xc61d) and ColorMatrix2 (0xc622) DNG tags are extracted using ExifTool and camera model and names are extracted using craw2tool -g from the CR2 file.

This information is then used for RGB calibration by pycraw2_demo.py

The goal here is to highlight the fact that:

  • this information can be extracted automatically
  • can be used outside of libcraw2 code

The only requirement, despite having CR2 samples, is to install the latest DNG converter tool which must support these camera models.

./dng_info.sh >dng_info.txt

some warnings are displayed, no problem.