I think the data transfer rates for the vast distance are inhibitive to the resolution. The 12m/pixel is only the HRSC. They plan to use the SRC device (up to 2m/pixel) on areas of interest after the mapping is complete.
http://www.lpi.usra.edu/meetings/sixthmars2003/pdf/3085.pdfhttp://berlinadmin.dlr.de/Missions/express/kamera/kameraeng.shtmlSRC Super Resolution Channel (2)
This is the high resoluting channel with an resolution of down to 2.3 m per pixel. SRC images will provide detailed information about areas of special interest, e.g. for the examination of future landing sites.
Data reduction and output
Combining the nine channels and the SRC together in full resolution, would result in an enormous data rate. The main antenna has a limited data rate and has a maximum of 8 hours per Earth-day for contact with the ground station. Thus there is a need of data reduction. This is performed by two methods - pixel summation and compression. The pixel summation creates averages of adjacent pixels. The 1X1 summation keeps the full resolution. The 2X2 summation creates an average of a square with an edge-length of 2 pixels. This decreases the data volume by a factor of four. Further options are a 4X4 and an 8X8 summation. The second method is a JPEG based data compression. After extensive tests with sample data, the compression factor has been determined to a variable factor between 4 and 10. This enables a compression of the data at acceptable losses in quality.
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