Compare how Netpbm declared[1] that colour images are BT.709 (HDTV) relatively late in its existence, and seemingly every other implementation ignores that and

Compare how Netpbm declared[1] that colour images are BT.709 (HDTV) relatively late in its existence, and seemingly every other implementation ignores that and treats them as sRGB (same—or close enough—primaries, different transfer function). [1] https://netpbm.sourceforge.net/doc/ppm.html https://netpbm.sourceforge.net/doc/ppm.html