The default compression of the IJG software (utilized in many, many software packages) is 4:1:1 JPEG, which is perfectly legal (standard) JPEG. However, the CL550 JPEG compression/decompression chip on the Parallax digital video cards uses the higher-quality 4:2:2 JPEG compression standard. Therefore, if your application utilizes the IJG software for JPEG compression, you must make a small modification to this software, and recompile in order to save in 4:2:2 format.
Edit the file "jcparam.c"
Look for the function "jpeg_set_colorspace()"
Look for the "case JCS_YCbCr:"
Change the first call to the Macro SET_COMP
SET_COMP(0, 1, 2, 2, 0, 0, 0);
SET_COMP(0, 1, 2, 1, 0, 0, 0);
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