cnv_jpeg_to_dng.py

#!/usr/bin/env python3

import os
import sys
import platform
import numpy as np
import tifffile as TIFF
import pyexiv2
from turbojpeg import TurboJPEG, TJPF_RGB
import argparse
from xphase_data import XphaseTransforms

#fugly, find a better solution for generating RATIONAL/SRATIONAL
def cm_to_flatrational(input_array):
    retarray = np.ones(input_array.size*2, dtype=np.int32)
    retarray[0::2] = (input_array.flatten()*10000).astype(np.int32)
    retarray[1::2] = 10000
    return retarray

def write_dng(jpegdata, exifdata, filebase):
    dll_names = {'Windows' : 'libturbojpeg.dll',
                'Linux' : 'libturbojpeg.so'}
    def init_TurboJPEG():
        if(hasattr(sys, 'frozen')):
            #Running under PyInstaller
            if(getattr(sys, 'frozen') == True):
                dll_path = os.path.join(getattr(sys, '_MEIPASS'), 'turbojpeg.libs', dll_names[platform.system()])
                return TurboJPEG(dll_path)
            else:
                exit('Running under PyInstaller single-file mode not yet supported')
        else:
            return TurboJPEG()

    xt = XphaseTransforms()
    jpeg = init_TurboJPEG()

    #DNG color matrix as SRATIONAL, pulled from an PanoManager DNG
    dng_color_matrix = [2147483647, 1268696091, -1208266623, 2147483647, -180777967, 2147483647,
                                -826519231, 2147483647, 2147483647, 1937550026, 683803903, 2147483647,
                                -128558463, 2147483647, 411880927, 2147483647, 2147483647, 2046508879]

    dngname = filebase + '.dng'

    rgbdata = jpeg.decode(jpegdata, pixel_format=TJPF_RGB)

    # It seems like every lens except 00, 01, 23, 24 are flipped upside down by PanoManager
    (garbage, lensnum, shotnum) = filebase.split("_",3)
    if int(lensnum) not in [0, 1, 23, 24] and exifdata['Exif.Image.Model'] != 'Scan':
        rgbdata = np.fliplr(np.flipud(rgbdata))

    #Colorspace and transfer function conversion
    rawdata = xt.jpeg_to_raw(rgbdata).astype(np.uint16)

    dng_extratags = []
    dng_extratags.append(('ColorMatrix1', '2i', 9, dng_color_matrix))
    dng_extratags.append(('CalibrationIlluminant1', 'H', 1, 23)) #is there an enum for this in tifffile???  23 = D50
    dng_extratags.append(('BlackLevel', 'H', 1, 0)) #BlackLevel - We subtracted black during processing, so it is 0
    dng_extratags.append(('WhiteLevel', 'I', 1, 65281)) #WhiteLevel
    dng_extratags.append(('DNGVersion', 'B', 4, [1,4,0,0])) #DNGVersion
    dng_extratags.append(('DNGBackwardVersion', 'B', 4, [1,4,0,0])) #DNGBackwardVersion
    dng_extratags.append(('AsShotNeutral', '2I', 3, [1, 1, 1, 1, 1, 1])) #Xphase pre-applies a D50 white balance so AsShotNeutral is 1.0, 1.0, 1.0 """

    with TIFF.TiffWriter(dngname) as dng:
        dng.write(rawdata,
                photometric=34892, #tiffile does not have enums for LinearRaw, use numeric instead
                extratags=dng_extratags)

if __name__ == "__main__":
    ap = argparse.ArgumentParser()
    ap.add_argument('-i', '--input', required=True,
        help='path to input file')

    args = vars(ap.parse_args())
    jpeg_file = args['input']

    filebase = os.path.splitext(jpeg_file)[0]
    with open(jpeg_file, 'rb') as jpgfile:
        write_dng(jpgfile.read(), {}, filebase)