A system and method facilitating progressively transforming and coding
digital pictures is provided. The present invention via employment of a
multi-resolution lapped transform provides for progressive rendering as
well as mitigation of blocking artifacts and ringing artifacts as
compared to many conventional compression systems. The invention includes
a color space mapper, a multi-resolution lapped transform, a quantizer, a
scanner and an entropy encoder. The multi-resolution lapped transform
outputs transform coefficients, for example, first transform coefficients
and second transform coefficients. A multi-resolution representation can
be obtained utilizing second transform coefficients of the
multi-resolution lapped transform. The color space mapper maps an input
image to a color space representation of the input image. The color space
representation of the input image is then provided to the
multi-resolution lapped transform. The quantizer receives the first
transform coefficients and/or the second transform coefficients and
provides an output of quantized coefficients for use by the scanner
and/or the entropy encoder. The scanner scans the quantized coefficients
in order to produce a one-dimensional vector for use by the entropy
encoder. The entropy encoder encodes the quantized coefficients received
from the quantizer and/or the scanner resulting in data compression.