fScanX Performance

Scanning Throughput

The following tables show the actual times required to scan 10 pages. The tests were all run on a dual 2.5gHz G5 with 2.5GB of RAM. This particular model was discontinued in 2005, so the comments below about the Mac not keeping up with higher-resolution grayscale & color scans are outdated. With current Mac models, fScanX can keep up with any scanner model, as shown on this page.

All times are in minutes and seconds. (These numbers are for older models, but in general for black-and-white scans you will get Fujitsu's rated speeds.)

Monochrome
single-sidedduplex
dpi fi-4120C2 fi-5650C fi-4120C2 fi-5650C
200 00:25 00:15 00:26 00:17
300 00:35 00:15 00:37 00:16
400 01:07 00:18 01:10 00:24
600 01:08 00:40 01:54 01:17

Grayscale
single-sidedduplex
dpi fi-4120C2 fi-5650C fi-4120C2 fi-5650C
200 00:25 00:15 00:27 00:16
300 00:37 00:17 00:40 00:33
400 01:10 00:36 01:13 01:10
600 01:39 01:32 02:31 02:58

Color
single-sidedduplex
dpi fi-4120C2 fi-5650C fi-4120C2 fi-5650C
200 00:40 00:15 00:51 00:25
300 00:51 00:32 01:22 01:01
400 02:16 00:54 03:08 01:46
600 03:19 02:06 05:47 06:07

CPU & RAM

The monochrome scans took ~5% of a single (old, PowerPC G4) CPU, so even much slower machines should show essentially the same performance. Monochrome scanning uses a maximum of ~9MB of RAM for buffering image data during scanning, so even machines without much RAM installed should show no RAM-related performance problems.

The grayscale and color scans took most of the processing power of a single CPU, indicating that slower machines should be expected to show slower performance. This is for uncompressed scans. Compressed color & grayscale scans at high resolutions will tax even current Intel CPUs.

Grayscale scanning uses a maximum of ~64MB of RAM for buffering image data during scanning, so a machine with constrained memory might see lowered performance. Color scanning can use a maximum of ~192MB RAM for buffering image data during scanning, so memory is very important for color scanning. Those buffer sizes are for 600dpi duplex scans; 300dpi will use 1/4 as much; single-sided will use 1/2 as much; 300dpi single-sided will use 1/8 as much. Take into account that if you want to do high-resolution grayscale or color scans, you will need an appropriate amount of RAM in order to fully take advantage of the scanner's performance.

The poorer performance of the 5650C on higher-resolution grayscale and color scans is because that model of scanner can feed paper in landscape mode and gets its highest throughput that way. This means that fScanX has to rotate the scans on the fly as the data comes in, and the current version doesn't keep up at 600dpi. (This was on a G4. Although that specific bottleneck does not apply with any recent Mac, at high-resolution color the new fi-6670 produces data faster than any Mac's USB bus can handle.)