Hardware Blitter on PS1 game running with PS3

It's nice to have PS1 game running in full HD (1080p) with PS3, even though the picture becomes pixelated. But I found that in one of my PS1 games, the game run with hardware blitter effect turned on. This occurred with japanese FFVIII game. Filtering effect is turned off but did not remove the hardware blitter effect. Could it be the hidden feature that embedded in PS1 emulator that available in PS3 or it control by game application? I'll try to add screenshot later on to give picture by picture comparison.