How do I extract the quantization coefficients from a jpeg file on Linux?
如何从Linux上的jpeg文件中提取量化系数?
I know they're in there somewhere!
我知道他们就在那里!
I see how to get them in Java: Reading quantization tables of jpeg files in Java
我看到了如何在Java中获取它们:在Java中读取jpeg文件的量化表
1 个解决方案
#1
8
djpeg does the trick
djpeg的技巧
$ djpeg -verbose -verbose foo.jpg > /dev/null
Independent JPEG Group's DJPEG, version 9 13-Jan-2013
Copyright (C) 2013, Thomas G. Lane, Guido Vollbeding
Start of Image
JFIF APP0 marker: version 1.01, density 72x72 1
Define Quantization Table 0 precision 0
1 1 1 1 2 3 4 5
1 1 1 2 2 5 5 4
1 1 1 2 3 5 6 4
1 1 2 2 4 7 6 5
1 2 3 4 5 9 8 6
2 3 4 5 6 8 9 7
4 5 6 7 8 10 10 8
6 7 8 8 9 8 8 8
Define Quantization Table 1 precision 0
1 1 2 4 8 8 8 8
1 2 2 5 8 8 8 8
2 2 4 8 8 8 8 8
4 5 8 8 8 8 8 8
8 8 8 8 8 8 8 8
8 8 8 8 8 8 8 8
8 8 8 8 8 8 8 8
8 8 8 8 8 8 8 8
#1
8
djpeg does the trick
djpeg的技巧
$ djpeg -verbose -verbose foo.jpg > /dev/null
Independent JPEG Group's DJPEG, version 9 13-Jan-2013
Copyright (C) 2013, Thomas G. Lane, Guido Vollbeding
Start of Image
JFIF APP0 marker: version 1.01, density 72x72 1
Define Quantization Table 0 precision 0
1 1 1 1 2 3 4 5
1 1 1 2 2 5 5 4
1 1 1 2 3 5 6 4
1 1 2 2 4 7 6 5
1 2 3 4 5 9 8 6
2 3 4 5 6 8 9 7
4 5 6 7 8 10 10 8
6 7 8 8 9 8 8 8
Define Quantization Table 1 precision 0
1 1 2 4 8 8 8 8
1 2 2 5 8 8 8 8
2 2 4 8 8 8 8 8
4 5 8 8 8 8 8 8
8 8 8 8 8 8 8 8
8 8 8 8 8 8 8 8
8 8 8 8 8 8 8 8
8 8 8 8 8 8 8 8