Appeal No. 2002-1777 Page 2
Application No. 08/953,219
data. (Spec. at 2, 14.) Consequently, if JPEG-coded data are lost or corrupted during
transmission, any subsequent data are meaningless, and none of the represented
image can be displayed. (Id. at 1-2.)
In contrast, the object of the invention is to configure image data, such as data
suitable for JPEG compression, into a format that can be streamed and displayed even
if part of the image is corrupted or lost during transmission. (Id. at 40.) More
specifically, image data grouped into JPEG minimum coded units ("MCUs") are
scrambled according to a reversible pattern that rearranges the MCUs vis-à-vis each
other. (Id. at 4.) Then, the scrambled image data are compressed into restartable
segments "by providing restart interval information to a JPEG compressor along with
the reorganized MCUs." (Id.) After compression, the data are packetized, with the
restart interval information written into headers that accompany of the packets, for
transmission. (Id. at 40.)
When the packets arrive at their destination, they are depacketized and parsed
to determine from their restart interval information which restart segments have arrived.
Each restart segment that has arrived is sent to a JPEG decompressor, resulting in a
scrambled bitmap image having gaps wherever data segments were lost. The image is
then unscrambled, resulting in small, isolated pixels of missing data scattered
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