Image 为什么我的JPEG文件比预期的大？

gm转换+配置文件“*”-调整大小800x800-质量90.0-背景白色-平坦测试.jpg test01.jpg

test01.jpg文件大小是140262，但是test.jpg文件大小是114698，我认为test01.jpg文件小于test.jpg，为什么

gm identify -verbose test.jpg command info:
Image: test.jpg
  Format: JPEG (Joint Photographic Experts Group JFIF format)
  Geometry: 960x1280
  Class: DirectClass
  Type: true color
  Depth: 8 bits-per-pixel component
  Channel Depths:
    Red:      8 bits
    Green:    8 bits
    Blue:     8 bits
  Channel Statistics:
    Red:
      Minimum:                     0.00 (0.0000)
      Maximum:                   255.00 (1.0000)
      Mean:                      158.69 (0.6223)
      Standard Deviation:         74.34 (0.2915)
    Green:
      Minimum:                     0.00 (0.0000)
      Maximum:                   255.00 (1.0000)
      Mean:                      142.36 (0.5583)
      Standard Deviation:         72.48 (0.2842)
    Blue:
      Minimum:                     0.00 (0.0000)
      Maximum:                   255.00 (1.0000)
      Mean:                      105.80 (0.4149)
      Standard Deviation:         73.05 (0.2865)
  Resolution: 72x72 pixels
  Filesize: 112.0Ki
  Interlace: No
  Orientation: TopLeft
  Background Color: white
  Border Color: #DFDFDF
  Matte Color: #BDBDBD
  Page geometry: 960x1280+0+0
  Compose: Over
  Dispose: Undefined
  Iterations: 0
  Compression: JPEG
  JPEG-Quality: 64
  JPEG-Colorspace: 2
  JPEG-Colorspace-Name: RGB
  JPEG-Sampling-factors: 2x2,1x1,1x1
  Signature: ea09bde85095c8c8b2345e5301d581a8002490ecfefa63ae81c0cb14b8c2fbf8
  Profile-iptc: 40 bytes
  Profile-EXIF: 86 bytes
    Orientation: 1
    Exif Offset: 38
    Color Space: 1
    Exif Image Width: 960
    Exif Image Length: 1280
  Tainted: False
  User Time: 0.020u
  Elapsed Time: 0:01
  Pixels Per Second: 39.1Mi

根据您为输入图像“test.jpg”提供的“标识”输出，JPEG质量估计为64。您要求输出图像的质量为90

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更高的质量意味着更大的文件大小。质量从64提高到90实际上并没有改善图像的视觉质量；它只会强制压缩器忠实地再现输入图像中的压缩伪影。

gm convert+profile“*”-调整大小800x800-质量90.0-背景白色-平坦测试。jpg test01.jpgSo您的期望是错误的。你的问题到底是什么？