03 图片质量.ipynb

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     "execution_count": 8,
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   "source": [
    "import cv2\n",
    "img = cv2.imread('image0.jpg',1)\n",
    "# cv2.imwrite('imageTest0.jpg', img, [cv2.IMWRITE_JPEG_QUALITY,0])  # 参数范围0-100    （*.jpg是有损压缩)\n",
    "cv2.imwrite('imageTest50.jpg', img, [cv2.IMWRITE_JPEG_QUALITY,50])"
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   "cell_type": "code",
   "execution_count": 12,
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     "execution_count": 12,
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   "source": [
    "# *.png是无损压缩 有一个透明度属性\n",
    "import cv2\n",
    "img = cv2.imread('image0.jpg',1)\n",
    "# cv2.imwrite('imageTest0.png', img, [cv2.IMWRITE_PNG_COMPRESSION,0])\n",
    "cv2.imwrite('imageTest9.png', img, [cv2.IMWRITE_PNG_COMPRESSION,9])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# 总结：对于*.jpg文件来说，参数数字（0-100）越小压缩比越高；\n",
    "#       对于*.png文件来说，参数数字（0-9）越小压缩比越低。"
   ]
  }
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