[fxp33]

Well, actually, no luck on the import, but the script here works:
- takes a Calibre catalog as input
- the covers must be in the first column
- outputs a css file with the covers as base64 BLOB

import csv
import base64
#assume cover paths are in the first column of the csv

with open('C:\Users\Fra\Documents\_permanent\Papier20150901.csv', 'rb') as file1, open('C:\Users\Fra\Documents\_permanent\Papier20150901covers.csv', 'wb') as file2:
    reader = csv.reader(file1, delimiter=',' , quotechar='"', doublequote = True)

    #No quotes around the headers
    #write without looking for path
    headers = next(reader, None)  # returns the headers or `None` if the input is empty
    if headers:
        writer = csv.writer(file2, delimiter=',', quoting=csv.QUOTE_NONE)
        writer.writerow(headers)

    #For all other lines, put double quotes around each cell
    writer = csv.writer(file2, delimiter=',', quoting=csv.QUOTE_ALL)

    for i, row in enumerate(reader):
        if row[0] == "":
            writer.writerow(row)
        else:
            with open(row[0], "rb") as image_file:
			 row[0] = base64.b64encode(image_file.read())
            writer.writerow(row)

Hope it helps someone...

François