There are multiple fixes for this, but at bare minimum, the driver should output more lines of white data.
allan On Sun, Jan 3, 2010 at 1:09 PM, Rainer Dorsch <rdorsch at web.de> wrote: > Hello, > > thanks, I run with SANE_DEBUG_EPSON2=255. The debug message and image data > seem to go both the stdout: > > http://www.bokomoko.de/~rd/test150.pnm.bz2 > > What I found interesting is that s->hw->color_shuffle seems to be false > > ? ? ? ?if (s->hw->color_shuffle) { > ? ? ? ? ? ? ? ?s->params.lines -= 4 * s->line_distance; > ? ? ? ? ? ? ? ?if (s->params.lines < 0) > ? ? ? ? ? ? ? ? ? ? ? ?s->params.lines = 0; > > ? ? ? ? ? ? ? ?DBG(1, "adjusted params.lines for color_shuffle by %d > to %d\n", > ? ? ? ? ? ? ? ? ? ?4 * s->line_distance, s->params.lines); > ? ? ? ?} > > ? ? ? ?DBG(5, "resolution = %d, preview = %d\n", > ? ? ? ? ? ?s->val[OPT_RESOLUTION].w, s->val[OPT_PREVIEW].w); > > since the "adjusted params.lines" does not show in the log: > > [epson2] main = 01, ADF = 00, TPU = 00, main 2 = 00 > [epson2] sane_epson2_start: scanning... > [epson2] e2_start_std_scan > [epson2] e2_send: size = 2, reply = 126486 > [epson2] e2_send: ESC G > [epson2] buf[0] 1b . > [epson2] buf[1] 47 G > [epson2] e2_send: cmd count, r = 40, w = 37 > [epson2] sane_epson2_get_parameters > [epson2] returning saved params structure > [epson2] restoring parameters from saved parameters > [epson2] resolution = 150, preview = 0 > [epson2] get para tlx 0.000000 tly 0.000000 brx 210.000000 bry 297.000000 [mm] > [epson2] params.format ? ? ? ? ?= 1 > [epson2] params.last_frame ? ? ?= 1 > [epson2] params.bytes_per_line ?= 3720 > [epson2] params.pixels_per_line = 1240 > [epson2] params.lines ? ? ? ? ? = 1754 > [epson2] params.depth ? ? ? ? ? = 8 > > Here it seem that the number of lines 1754 (=297/25.4*150) is still ok. > > Later epson2 reports: > [epson2] e2_block_sane_read: begin > [epson2] written 1750 lines after color shuffle > [epson2] lines requested: 1754 > [epson2] moving data 32768 0x8ca6d18 0x8ca6d18 > > This seems to be the 4 lines of discrepance (the 12 lines Allan and me > mentioned before were wrong, it is 3 byte per pixel). > > The debug code from above comes from here (epson2-ops.c) > > ? ? ? ? ? ? ? ?if (s->eof) { > ? ? ? ? ? ? ? ? ? ? ? ?if (s->hw->color_shuffle) { > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?DBG(1, > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?"written %d lines after color shuffle\n", > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?s->lines_written); > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?DBG(1, "lines requested: %d\n", > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?s->params.lines); > ? ? ? ? ? ? ? ? ? ? ? ?} > > ? ? ? ? ? ? ? ? ? ? ? ?return SANE_STATUS_EOF; > ? ? ? ? ? ? ? ?} > > Is it correct that the epson2 backend > -> requests the scanner to scan 1754 lines > -> it acctually only scanned 1750 lines > > This mismatch is in the pnm file. Is the 1754 written before we start > scanning, i.e. the backend needs to predict the correct number of lines the > scanner scans? > > Can you point me to the locations in the code? > > Thanks, > Rainer > > Am Sonntag, 3. Januar 2010 schrieb Alessandro Zummo: >> On Sun, 3 Jan 2010 15:14:38 +0100 >> >> Rainer Dorsch <rdorsch at web.de> wrote: >> > Are these the areas in epson2.c you are refering to: >> > >> > ? ? ? ? /* >> > ? ? ? ? ?* Make sure that the number of lines is correct for color >> > shuffling: * The shuffling alghorithm produces 2xline_distance lines at >> > the * beginning and the same amount at the end of the scan that are not * >> > useable. If s->params.lines gets negative, 0 lines are reported * back to >> > the frontend. >> > ? ? ? ? ?*/ >> > ? ? ? ? if (s->hw->color_shuffle) { >> > ? ? ? ? ? ? ? ? s->params.lines -= 4 * s->line_distance; >> > ? ? ? ? ? ? ? ? if (s->params.lines < 0) >> > ? ? ? ? ? ? ? ? ? ? ? ? s->params.lines = 0; >> > >> > ? ? ? ? ? ? ? ? DBG(1, "adjusted params.lines for color_shuffle by %d >> > to %d\n", >> > ? ? ? ? ? ? ? ? ? ? 4 * s->line_distance, s->params.lines); >> > ? ? ? ? } >> > >> > ? ? ? ? DBG(5, "resolution = %d, preview = %d\n", >> > ? ? ? ? ? ? s->val[OPT_RESOLUTION].w, s->val[OPT_PREVIEW].w); >> > >> > ? ? ? ? DBG(5, "get para %p %p tlx %f tly %f brx %f bry %f [mm]\n", >> > ? ? ? ? ? ? (void *) s, (void *) s->val, SANE_UNFIX(s->val[OPT_TL_X].w), >> > ? ? ? ? ? ? SANE_UNFIX(s->val[OPT_TL_Y].w), >> > SANE_UNFIX(s->val[OPT_BR_X].w), SANE_UNFIX(s->val[OPT_BR_Y].w)); >> > >> > and >> > >> > ? ? ? ? /* allocate buffers for color shuffling */ >> > ? ? ? ? if (dev->color_shuffle == SANE_TRUE) { >> > ? ? ? ? ? ? ? ? int i; >> > ? ? ? ? ? ? ? ? /* initialize the line buffers */ >> > ? ? ? ? ? ? ? ? for (i = 0; i < s->line_distance * 2 + 1; i++) { >> > >> > ? ? ? ? ? ? ? ? ? ? ? ? if (s->line_buffer[i] != NULL) >> > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? free(s->line_buffer[i]); >> > >> > ? ? ? ? ? ? ? ? ? ? ? ? s->line_buffer[i] = >> > malloc(s->params.bytes_per_line); if (s->line_buffer[i] == NULL) { >> > ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? DBG(1, "out of memory (line %d)\n", >> > __LINE__); return SANE_STATUS_NO_MEM; >> > ? ? ? ? ? ? ? ? ? ? ? ? } >> > ? ? ? ? ? ? ? ? } >> > ? ? ? ? } >> > >> > I think a first good step would be to enable debug output. >> > >> > How can I enable the output in DBG() from scanimage ? >> >> ?Those are two of the involved sections. However I did not wrote >> them so I can just hope they work nicely ;) >> >> ?You can enable debug with SANE_DEBUG_EPSON2=XX >> where XX is a value between 1 and 255. >> >> ?Thanks for the remote access offer but I'll be quite busy for the >> ?forthcoming weeks :( >> >> > > ?For such a scanner, I'd suggest to scan a bigger area >> > > and then refine by software. >> > >> > I to now worry a lot about the 2-3 mm missing in the scan (12 lines at >> > 150dpi), the problem is that the pnm file is broken and most programs >> > reject to work with it. E.g. gscan2pdf uses convert from imagemagick to >> > generate pdfs. But that all only works it the pnm files are correct and >> > not corrupted. For me a fix which at least generates correct pnm files >> > would be fine. >> >> ?Did you tried other scanning software? > > > > -- > Rainer Dorsch > L?rchenstr. 6 > D-72135 Dettenhausen > 07157-734133 > email: rdorsch at web.de > jabber: rdorsch at jabber.org > GPG Fingerprint: 5966 C54C 2B3C 42CC 1F4F ?8F59 E3A8 C538 7519 141E > Full GPG key: http://pgp.mit.edu/ > -- "The truth is an offense, but not a sin"
