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Your image change it resolution when you use Matrix and transform it?
Use a Paint and setFilterBitmap and setAntiAlias to true and thats all, you bitmap colors will not going to be changed at all…
<pre style="background-image: URL(http://2.bp.blogspot.com/_z5ltvMQPaa8/SjJXr_U2YBI/AAAAAAAAAAM/46OqEP32CJ8/s320/codebg.gif); background: #f0f0f0; border: 1px dashed #CCCCCC; color: black; font-family: arial; font-size: 12px; height: auto; line-height: 20px; overflow: auto; padding: 0px; text-align: left; width: 99%;"> Paint paint = new Paint();
</pre>
paint.setAntiAlias(true);
paint.setFilterBitmap(true);
canvas.drawBitmap(bitmap, matrix, paint);
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