Custom Quantization Tables using defineValue
Posted: 2016-10-25T08:37:55-07:00
Hello, I think I found a bug. It could be attributed to user error, but I think I've ruled out that possibility.
The problem is in supplying a "quantization-table.xml" I wish to encode with the following QTs in a C++ program:
This is the c++ code I'm using:
However, in my "out.jpg" I'm ending up with these QTs:
Thanks for the help in advance!
The problem is in supplying a "quantization-table.xml" I wish to encode with the following QTs in a C++ program:
Code: Select all
Luminance Quantization Table
16, 12, 14, 17, 22, 30, 45, 72,
12, 13, 14, 17, 22, 31, 46, 74,
14, 14, 16, 19, 25, 35, 52, 83,
17, 17, 19, 23, 30, 41, 62, 100,
22, 22, 25, 30, 39, 54, 80, 129,
30, 31, 35, 41, 54, 74, 111, 178,
45, 46, 52, 62, 80, 111, 166, 267,
72, 74, 83, 100, 129, 178, 267, 428
Chrominance Quantization Table
17, 18, 22, 31, 50, 92, 193, 465,
18, 19, 24, 33, 54, 98, 207, 498,
22, 24, 29, 41, 66, 120, 253, 609,
31, 33, 41, 57, 92, 169, 355, 854,
50, 54, 66, 92, 148, 271, 570, 1370,
92, 98, 120, 169, 271, 498, 1046, 2516,
193, 207, 253, 355, 570, 1046, 2198, 5289,
465, 498, 609, 854, 1370, 2516, 5289, 12725Code: Select all
image.read( "in.jpg" );
image.defineValue("jpeg", "q-table", "quantization-table.xml");
image.write( "out.jpg" );Code: Select all
Luminance Quantization Table
2, 2, 2, 2, 3, 4, 6, 10
2, 2, 2, 2, 3, 4, 6, 10
2, 2, 2, 3, 4, 5, 7, 12
2, 2, 3, 3, 4, 6, 9, 14
3, 3, 4, 4, 5, 8, 11, 18
4, 4, 5, 6, 8, 10, 16, 25
6, 6, 7, 9, 11, 16, 23, 37
10, 10, 12, 14, 18, 25, 37, 60
Chrominance Quantization Table
2, 3, 3, 4, 7, 13, 27, 65
3, 3, 3, 5, 8, 14, 29, 70
3, 3, 4, 6, 9, 17, 35, 85
4, 5, 6, 8, 13, 24, 50 120
7, 8, 9, 13, 21, 38, 80 192
13, 14, 17, 24, 38, 70 146 352
27, 29, 35, 50, 80 146 308 740
65, 70, 85 120 192 352 740 1782