[Swftools-common] -O1 optimize seems set image resolution too low

[Jonathan Lee]

Hello swftools community:
The flag -O1 works good, except for it set the image quality too low. I like to 
have the image still very clear at least zoom to 150%

For some pdf file, seems when I do not use -O1 flag, the converted swf file 
size is nearly same, sometimes, even bigger than the pdf file. I used the flag 
-s jpegquality=50

So, what I want is something with higher image quality than -O1, but still can 
reduce the file size greatly.

Any ideas?

Thanks