Patent ID: 9154800
Filing Date: 2015-10-06
Classification: H04N

Abstract:
1. A computer implemented method comprising: accessing a progressive JPEG image, wherein the progressive JPEG image comprises a plurality of compressed scans and wherein each compressed scan in the plurality of compressed scans comprises a plurality of compressed rows of image data; decompressing not more than half of the compressed rows of each compressed scan in the plurality of compressed scans into a memory buffer; copying a remaining plurality of compressed rows of each compressed scan in the plurality of compressed scans into a plurality of small memory buffers; decoding, in place, the decompressed rows in the memory buffer; storing the decoded decompressed rows in the memory buffer; decompressing, from the small memory buffers, not more than half of the remaining compressed rows of each compressed scan in the plurality of compressed scans into the memory buffer; decoding the rows decompressed from the plurality of small memory buffers in the memory buffer; storing the decoded rows decompressed from the plurality of small memory buffers in the memory buffer; and repeating the steps of decompressing, decoding, and storing the remaining compressed rows in the plurality of small memory buffers until a predefined number of rows are remaining in the plurality of small memory buffers, at which time the remaining rows are decompressed and decoded.