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Diffstat (limited to 'backend/genesys_conv.c')
| -rw-r--r-- | backend/genesys_conv.c | 478 |
1 files changed, 478 insertions, 0 deletions
diff --git a/backend/genesys_conv.c b/backend/genesys_conv.c new file mode 100644 index 0000000..61ac782 --- /dev/null +++ b/backend/genesys_conv.c @@ -0,0 +1,478 @@ +/* sane - Scanner Access Now Easy. + + Copyright (C) 2005, 2006 Pierre Willenbrock <pierre@pirsoft.dnsalias.org> + Copyright (C) 2010-2013 Stéphane Voltz <stef.dev@free.fr> + + This file is part of the SANE package. + + This program is free software; you can redistribute it and/or + modify it under the terms of the GNU General Public License as + published by the Free Software Foundation; either version 2 of the + License, or (at your option) any later version. + + This program is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place - Suite 330, Boston, + MA 02111-1307, USA. + + As a special exception, the authors of SANE give permission for + additional uses of the libraries contained in this release of SANE. + + The exception is that, if you link a SANE library with other files + to produce an executable, this does not by itself cause the + resulting executable to be covered by the GNU General Public + License. Your use of that executable is in no way restricted on + account of linking the SANE library code into it. + + This exception does not, however, invalidate any other reasons why + the executable file might be covered by the GNU General Public + License. + + If you submit changes to SANE to the maintainers to be included in + a subsequent release, you agree by submitting the changes that + those changes may be distributed with this exception intact. + + If you write modifications of your own for SANE, it is your choice + whether to permit this exception to apply to your modifications. + If you do not wish that, delete this exception notice. +*/ + +/* + * Conversion filters for genesys backend + */ + + +/*8 bit*/ +#define SINGLE_BYTE +#define BYTES_PER_COMPONENT 1 +#define COMPONENT_TYPE uint8_t + +#define FUNC_NAME(f) f ## _8 + +#include "genesys_conv_hlp.c" + +#undef FUNC_NAME + +#undef COMPONENT_TYPE +#undef BYTES_PER_COMPONENT +#undef SINGLE_BYTE + +/*16 bit*/ +#define DOUBLE_BYTE +#define BYTES_PER_COMPONENT 2 +#define COMPONENT_TYPE uint16_t + +#define FUNC_NAME(f) f ## _16 + +#include "genesys_conv_hlp.c" + +#undef FUNC_NAME + +#undef COMPONENT_TYPE +#undef BYTES_PER_COMPONENT +#undef DOUBLE_BYTE + +static SANE_Status +genesys_reverse_bits( + uint8_t *src_data, + uint8_t *dst_data, + size_t bytes) +{ + size_t i; + for(i = 0; i < bytes; i++) { + *dst_data++ = ~ *src_data++; + } + return SANE_STATUS_GOOD; +} + +/** + * uses the threshold/threshold_curve to control software binarization + * This code was taken from the epjistsu backend by m. allan noah + * @param dev device set up for the scan + * @param src pointer to raw data + * @param dst pointer where to store result + * @param width width of the processed line + * */ +static SANE_Status +binarize_line(Genesys_Device * dev, uint8_t *src, uint8_t *dst, int width) +{ + int j, windowX, sum = 0; + int thresh; + int offset, addCol, dropCol; + unsigned char mask; + + int x; + uint8_t min, max; + + /* normalize line */ + min = 255; + max = 0; + for (x = 0; x < width; x++) + { + if (src[x] > max) + { + max = src[x]; + } + if (src[x] < min) + { + min = src[x]; + } + } + + /* safeguard against dark or white areas */ + if(min>80) + min=0; + if(max<80) + max=255; + for (x = 0; x < width; x++) + { + src[x] = ((src[x] - min) * 255) / (max - min); + } + + /* ~1mm works best, but the window needs to have odd # of pixels */ + windowX = (6 * dev->settings.xres) / 150; + if (!(windowX % 2)) + windowX++; + + /* second, prefill the sliding sum */ + for (j = 0; j < windowX; j++) + sum += src[j]; + + /* third, walk the input buffer, update the sliding sum, */ + /* determine threshold, output bits */ + for (j = 0; j < width; j++) + { + /* output image location */ + offset = j % 8; + mask = 0x80 >> offset; + thresh = dev->settings.threshold; + + /* move sum/update threshold only if there is a curve */ + if (dev->settings.threshold_curve) + { + addCol = j + windowX / 2; + dropCol = addCol - windowX; + + if (dropCol >= 0 && addCol < width) + { + sum -= src[dropCol]; + sum += src[addCol]; + } + thresh = dev->lineart_lut[sum / windowX]; + } + + /* use average to lookup threshold */ + if (src[j] > thresh) + *dst &= ~mask; /* white */ + else + *dst |= mask; /* black */ + + if (offset == 7) + dst++; + } + + return SANE_STATUS_GOOD; +} + +/** + * software lineart using data from a 8 bit gray scan. We assume true gray + * or monochrome scan as input. + */ +static SANE_Status +genesys_gray_lineart( + Genesys_Device *dev, + uint8_t *src_data, + uint8_t *dst_data, + size_t pixels, + size_t lines, + uint8_t threshold) +{ + size_t y; + + DBG (DBG_io2, "genesys_gray_lineart: converting %lu lines of %lu pixels\n", + (unsigned long)lines, (unsigned long)pixels); + DBG (DBG_io2, "genesys_gray_lineart: threshold=%d\n",threshold); + + for (y = 0; y < lines; y++) + { + binarize_line (dev, src_data + y * pixels, dst_data, pixels); + dst_data += pixels / 8; + } + return SANE_STATUS_GOOD; +} + +/** @brief shrink or grow scanned data to fit the final scan size + * This function shrinks the scanned data it the required resolution is lower than the hardware one, + * or grows it in case it is the opposite like when motor resolution is higher than + * sensor's one. + */ +static SANE_Status +genesys_shrink_lines_1 ( + uint8_t *src_data, + uint8_t *dst_data, + unsigned int lines, + unsigned int src_pixels, + unsigned int dst_pixels, + unsigned int channels) +{ + unsigned int dst_x, src_x, y, c, cnt; + unsigned int avg[3], val; + uint8_t *src = (uint8_t *) src_data; + uint8_t *dst = (uint8_t *) dst_data; + + /* choose between case where me must reduce or grow the scanned data */ + if (src_pixels > dst_pixels) + { + /* shrink data */ + /* TODO action must be taken at bit level, no bytes */ + src_pixels /= 8; + dst_pixels /= 8; + /*take first _byte_ */ + for (y = 0; y < lines; y++) + { + cnt = src_pixels / 2; + src_x = 0; + for (dst_x = 0; dst_x < dst_pixels; dst_x++) + { + while (cnt < src_pixels && src_x < src_pixels) + { + cnt += dst_pixels; + + for (c = 0; c < channels; c++) + avg[c] = *src++; + src_x++; + } + cnt -= src_pixels; + + for (c = 0; c < channels; c++) + *dst++ = avg[c]; + } + } + } + else + { + /* common case where y res is double x res */ + for (y = 0; y < lines; y++) + { + if (2 * src_pixels == dst_pixels) + { + /* double and interleave on line */ + for (c = 0; c < src_pixels/8; c++) + { + /* first 4 bits */ + val = 0; + val |= (*src & 0x80) >> 0; /* X___ ____ --> X___ ____ */ + val |= (*src & 0x80) >> 1; /* X___ ____ --> _X__ ____ */ + val |= (*src & 0x40) >> 1; /* _X__ ____ --> __X_ ____ */ + val |= (*src & 0x40) >> 2; /* _X__ ____ --> ___X ____ */ + val |= (*src & 0x20) >> 2; /* __X_ ____ --> ____ X___ */ + val |= (*src & 0x20) >> 3; /* __X_ ____ --> ____ _X__ */ + val |= (*src & 0x10) >> 3; /* ___X ____ --> ____ __X_ */ + val |= (*src & 0x10) >> 4; /* ___X ____ --> ____ ___X */ + *dst = val; + dst++; + + /* last for bits */ + val = 0; + val |= (*src & 0x08) << 4; /* ____ X___ --> X___ ____ */ + val |= (*src & 0x08) << 3; /* ____ X___ --> _X__ ____ */ + val |= (*src & 0x04) << 3; /* ____ _X__ --> __X_ ____ */ + val |= (*src & 0x04) << 2; /* ____ _X__ --> ___X ____ */ + val |= (*src & 0x02) << 2; /* ____ __X_ --> ____ X___ */ + val |= (*src & 0x02) << 1; /* ____ __X_ --> ____ _X__ */ + val |= (*src & 0x01) << 1; /* ____ ___X --> ____ __X_ */ + val |= (*src & 0x01) << 0; /* ____ ___X --> ____ ___X */ + *dst = val; + dst++; + src++; + } + } + else + { + /* TODO: since depth is 1, we must interpolate bit within bytes */ + DBG (DBG_warn, "%s: inaccurate bit expansion!\n", __FUNCTION__); + cnt = dst_pixels / 2; + dst_x = 0; + for (src_x = 0; src_x < src_pixels; src_x++) + { + for (c = 0; c < channels; c++) + avg[c] = *src++; + while (cnt < dst_pixels && dst_x < dst_pixels) + { + cnt += src_pixels; + for (c = 0; c < channels; c++) + *dst++ = avg[c]; + dst_x++; + } + cnt -= dst_pixels; + } + } + } + } + + return SANE_STATUS_GOOD; +} + + +/** Look in image for likely left/right/bottom paper edges, then crop image. + * Since failing to crop isn't fatal, we always return SANE_STATUS_GOOD . + */ +static SANE_Status +genesys_crop(Genesys_Scanner *s) +{ + SANE_Status status; + Genesys_Device *dev = s->dev; + int top = 0; + int bottom = 0; + int left = 0; + int right = 0; + + DBG (DBG_proc, "%s: start\n", __FUNCTION__); + + /* first find edges if any */ + status = sanei_magic_findEdges (&s->params, + dev->img_buffer, + dev->settings.xres, + dev->settings.yres, + &top, + &bottom, + &left, + &right); + if (status != SANE_STATUS_GOOD) + { + DBG (DBG_info, "%s: bad or no edges, bailing\n", __FUNCTION__); + goto cleanup; + } + DBG (DBG_io, "%s: t:%d b:%d l:%d r:%d\n", __FUNCTION__, top, bottom, left, + right); + + /* now crop the image */ + status = + sanei_magic_crop (&(s->params), dev->img_buffer, top, bottom, left, right); + if (status) + { + DBG (DBG_warn, "%s: failed to crop\n", __FUNCTION__); + goto cleanup; + } + + /* update counters to new image size */ + dev->total_bytes_to_read = s->params.bytes_per_line * s->params.lines; + +cleanup: + DBG (DBG_proc, "%s: completed\n", __FUNCTION__); + return SANE_STATUS_GOOD; +} + +/** Look in image for likely upper and left paper edges, then rotate + * image so that upper left corner of paper is upper left of image. + * @return since failure doens't prevent scanning, we always return + * SANE_STATUS_GOOD + */ +static SANE_Status +genesys_deskew(Genesys_Scanner *s) +{ + SANE_Status status; + Genesys_Device *dev = s->dev; + + int x = 0, y = 0, bg; + double slope = 0; + + DBG (DBG_proc, "%s: start\n", __FUNCTION__); + + bg=0; + if(s->params.format==SANE_FRAME_GRAY && s->params.depth == 1) + { + bg=0xff; + } + status = sanei_magic_findSkew (&s->params, + dev->img_buffer, + dev->sensor.optical_res, + dev->sensor.optical_res, + &x, + &y, + &slope); + if (status!=SANE_STATUS_GOOD) + { + DBG (DBG_error, "%s: bad findSkew, bailing\n", __FUNCTION__); + return SANE_STATUS_GOOD; + } + DBG(DBG_info, "%s: slope=%f => %f\n",__FUNCTION__,slope, (slope/M_PI_2)*90); + /* rotate image slope is in [-PI/2,PI/2] + * positive values rotate trigonometric direction wise */ + status = sanei_magic_rotate (&s->params, + dev->img_buffer, + x, + y, + slope, + bg); + if (status!=SANE_STATUS_GOOD) + { + DBG (DBG_error, "%s: rotate error: %s", __FUNCTION__, sane_strstatus(status)); + } + + DBG (DBG_proc, "%s: completed\n", __FUNCTION__); + return SANE_STATUS_GOOD; +} + +/** remove lone dots + * @return since failure doens't prevent scanning, we always return + * SANE_STATUS_GOOD + */ +static SANE_Status +genesys_despeck(Genesys_Scanner *s) +{ + if(sanei_magic_despeck(&s->params, + s->dev->img_buffer, + s->val[OPT_DESPECK].w)!=SANE_STATUS_GOOD) + { + DBG (DBG_error, "%s: bad despeck, bailing\n",__FUNCTION__); + } + + return SANE_STATUS_GOOD; +} + +/** Look if image needs rotation and apply it + * */ +static SANE_Status +genesys_derotate (Genesys_Scanner * s) +{ + SANE_Status status; + int angle = 0; + int resolution = s->val[OPT_RESOLUTION].w; + + DBGSTART; + status = sanei_magic_findTurn (&s->params, + s->dev->img_buffer, + resolution, + resolution, + &angle); + + if (status) + { + DBG (DBG_warn, "%s: failed : %d\n", __FUNCTION__, status); + DBGCOMPLETED; + return SANE_STATUS_GOOD; + } + + /* apply rotation angle found */ + status = sanei_magic_turn (&s->params, s->dev->img_buffer, angle); + if (status) + { + DBG (DBG_warn, "%s: failed : %d\n", __FUNCTION__, status); + DBGCOMPLETED; + return SANE_STATUS_GOOD; + } + + /* update counters to new image size */ + s->dev->total_bytes_to_read = s->params.bytes_per_line * s->params.lines; + + DBGCOMPLETED; + return SANE_STATUS_GOOD; +} + +/* vim: set sw=2 cino=>2se-1sn-1s{s^-1st0(0u0 smarttab expandtab: */ |