PNG_IMAGE_FLAG_16BIT_sRGB

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
version(!PNG_VERSION_INFO_ONLY)
extern (C)
static if(PNG_SIMPLIFIED_READ_SUPPORTED || PNG_SIMPLIFIED_WRITE_SUPPORTED)
enum PNG_IMAGE_FLAG_16BIT_sRGB = 0x04;

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