问使用JPEG压缩保存多通道(n > 3)图像(python)

EN

#!/usr/bin/python3

import sys
import pyvips

def load(filename):
    return pyvips.Image.new_from_file(filename)

# load a couple of eg. three-band images to make a 6-band image
image = load(sys.argv[2]).bandjoin(load(sys.argv[3]))

# to convert to OME, we need a tall, thin mono image with page-height set to
# indicate where the joins are
ome = pyvips.Image.arrayjoin(image.bandsplit(), across=1)

# you must make a private copy before modifying image metadata
ome = ome.copy()
ome.set_type(pyvips.GValue.gint_type, 'page-height', image.height)

# now we can write as a pyramid
# libvips 8.10+ will put the pyramid layers into SUBIFDs
ome.tiffsave(sys.argv[1], pyramid=True, compression="jpeg", Q=90)

$ ./gen_ome.py x.tif ~/pics/1.tiff ~/pics/2.tiff 
$ tiffinfo x.tif 
TIFF Directory at offset 0x173f02 (1523458)
  Subfile Type: multi-page document (2 = 0x2)
  Image Width: 6048 Image Length: 4032
  Tile Width: 128 Tile Length: 128
  Resolution: 300, 300 pixels/inch
  Bits/Sample: 8
  Sample Format: unsigned integer
  Compression Scheme: JPEG
  Photometric Interpretation: min-is-black
  Orientation: row 0 top, col 0 lhs
  Samples/Pixel: 1
  Planar Configuration: single image plane
  Page Number: 0-6
  SubIFD Offsets: 2153288 2339670 2396406 2415400 2422262 2424960
  JPEG Tables: (73 bytes)
TIFF Directory at offset 0x3c3b2c (3947308)
  Subfile Type: multi-page document (2 = 0x2)
  Image Width: 6048 Image Length: 4032
  Tile Width: 128 Tile Length: 128
...