why the jpeg picture quality is aweful which is encoded by Bitmapdata.encode?

[freetop_gl]

why the jpeg picture quality is aweful which is encoded by  Bitmapdata.encode?

var result:ByteArray=bmd.encode(bmd.rect,new JPEGEncoderOptions(90));

[kglad]

increase the quality parameter if you want greater fidelity.

[freetop_gl]

no matter whatever quality is , the result is worse than which is return by JPEGEncoder.

[kglad]

then don't compress the data.