summaryrefslogtreecommitdiff
path: root/backend/pieusb_buffer.c
diff options
context:
space:
mode:
authorJörg Frings-Fürst <debian@jff-webhosting.net>2015-10-08 12:32:49 +0200
committerJörg Frings-Fürst <debian@jff-webhosting.net>2015-10-08 12:32:49 +0200
commitcfd27ef2ad8b005fd47ab41ef29b71d9e3d48201 (patch)
tree56cb8849a5df91b19b72fd4f48c79c343cd9bc5e /backend/pieusb_buffer.c
parentba8d09abe681600aad991f4a75e904615b7ed29f (diff)
Imported Upstream version 1.0.25upstream/1.0.25
Diffstat (limited to 'backend/pieusb_buffer.c')
-rw-r--r--backend/pieusb_buffer.c644
1 files changed, 644 insertions, 0 deletions
diff --git a/backend/pieusb_buffer.c b/backend/pieusb_buffer.c
new file mode 100644
index 0000000..53bd867
--- /dev/null
+++ b/backend/pieusb_buffer.c
@@ -0,0 +1,644 @@
+/* sane - Scanner Access Now Easy.
+
+ pieusb_buffer.c
+
+ Copyright (C) 2012-2015 Jan Vleeshouwers, Michael Rickmann, Klaus Kaempf
+
+ 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. */
+
+/* =========================================================================
+ *
+ * Read buffer
+ *
+ * Data obtained from the scanner cannot be presented to the frontend immediately.
+ * The scanner returns data in the 'index' or 'line' color format, which means it
+ * returns data in batches which contain a single color of a scan line.
+ *
+ * These must finally be converted into the SANE data format (data for a single
+ * pixel in consecutive bytes). Apart from that, sane_read() must be able to
+ * return any amount of data bytes.
+ *
+ * In between, data processing may be necessary, usually requiring the whole
+ * image to be available.
+ *
+ * To accommodate all this, the buffer stores all samples as 16-bit values, even
+ * if the original values are 8-bit or even 1 bit. This is a waste of space, but
+ * makes processing much easier, and it is only temporary.
+ *
+ * The read buffer is constructed by a call to buffer_create(), which initializes
+ * the buffer based on width, height, number of colors and depth. The buffer
+ * contains data organized in color planes, with each plane consisting of lines,
+ * each line of a fixed number of (single color) pixels, and each pixel of a fixed
+ * number of bits (or bytes).
+ *
+ * The buffer maintains read and write pointers.
+ *
+ * Multi-color data with a bit depth of 1 are packed in single color bytes, so
+ * the data obtained from the scanner does not need conversion.
+ *
+ * ========================================================================= */
+
+#define DEBUG_DECLARE_ONLY
+
+/* Configuration defines */
+#include "../include/sane/config.h"
+
+/* SANE includes */
+#include "../include/sane/sane.h"
+#include "../include/sane/saneopts.h"
+#include "../include/sane/sanei_usb.h"
+#include "../include/sane/sanei_config.h"
+
+/* Backend includes */
+#define BACKEND_NAME pieusb
+#include "../include/sane/sanei_backend.h"
+#include "pieusb.h"
+
+#include "pieusb_specific.h"
+#include "pieusb_buffer.h"
+
+#ifdef HAVE_ALLOCA_H
+#include <alloca.h>
+#endif
+
+#include <stdio.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <endian.h>
+
+/* When creating the release backend, make complains about unresolved external
+ * le16toh, although it finds the include <endian.h> */
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+ #define le16toh(x) (x)
+#else
+ #define le16toh(x) __bswap_16 (x)
+#endif
+
+static void buffer_update_read_index(struct Pieusb_Read_Buffer* buffer, int increment);
+
+/* READER */
+
+/**
+ * Initialize the buffer.
+ * A scanner has a Pieusb_Read_Buffer struct as one of its members.
+ *
+ * @param buffer the buffer to initialize
+ * @param width number of pixels on a line (row)
+ * @param height number of lines in the buffer (pixels in a column)
+ * @param colors bitmap specifying the colors in the scanned data (bitmap: 0000 IBGR)
+ * @param depth number of bits of a color
+ * @param bigendian how to store multi-byte values: bigendian if true
+ * @param maximum_size maximum size of buffer (-1 = size of image)
+ */
+
+SANE_Status
+sanei_pieusb_buffer_create(struct Pieusb_Read_Buffer* buffer, SANE_Int width, SANE_Int height, SANE_Byte color_spec, SANE_Byte depth)
+{
+ int k, result;
+ unsigned int buffer_size_bytes;
+ unsigned char g;
+
+ /* Base parameters */
+ buffer->width = width;
+ buffer->height = height;
+ buffer->colors = 0;
+ if (color_spec & 0x01) { buffer->color_index_red = 0; buffer->colors++; } else { buffer->color_index_red = -1; }
+ if (color_spec & 0x02) { buffer->color_index_green = 1; buffer->colors++; } else { buffer->color_index_green = -1; }
+ if (color_spec & 0x04) { buffer->color_index_blue = 2; buffer->colors++; } else { buffer->color_index_blue = -1; }
+ if (color_spec & 0x08) { buffer->color_index_infrared = 3; buffer->colors++; } else { buffer->color_index_infrared = -1; }
+ if (buffer->colors == 0) {
+ DBG(DBG_error, "sanei_pieusb_buffer_create(): no colors specified\n");
+ return SANE_STATUS_INVAL;
+ }
+ buffer->depth = depth;
+ if (depth < 1 || depth > 16) {
+ DBG(DBG_error, "sanei_pieusb_buffer_create(): unsupported depth %d\n", depth);
+ return SANE_STATUS_INVAL;
+ }
+ buffer->packing_density = (depth == 1) ? 8 : 1; /* These are all the situations we have */
+
+ /* Derived*/
+ buffer->packet_size_bytes = (buffer->depth * buffer->packing_density + 7) / 8;
+ buffer->line_size_packets = (buffer->width + buffer->packing_density -1) / buffer->packing_density;
+ buffer->line_size_bytes = buffer->line_size_packets * buffer->packet_size_bytes;
+ buffer->image_size_bytes = buffer->colors * buffer->height * buffer->line_size_bytes;
+
+ /* Create empty file */
+ snprintf(buffer->buffer_name, L_tmpnam, "/tmp/sane.XXXXXX");
+ if (buffer->data_file != 0) /* might still be open from previous invocation */
+ close(buffer->data_file);
+ buffer->data_file = mkostemp(buffer->buffer_name, O_RDWR | O_CREAT | O_EXCL | O_TRUNC);
+ if (buffer->data_file == -1) {
+ buffer->data_file = 0;
+ buffer->data = NULL;
+ perror("sanei_pieusb_buffer_create(): error opening image buffer file");
+ return SANE_STATUS_IO_ERROR;
+ }
+ /* Stretch the file size */
+ buffer_size_bytes = buffer->width * buffer->height * buffer->colors * sizeof(SANE_Uint);
+ if (buffer_size_bytes == 0) {
+ close(buffer->data_file);
+ buffer->data_file = 0;
+ DBG(DBG_error, "sanei_pieusb_buffer_create(): buffer_size is zero: width %d, height %d, colors %d\n", buffer->width, buffer->height, buffer->colors);
+ return SANE_STATUS_INVAL;
+ }
+ result = lseek(buffer->data_file, buffer_size_bytes-1, SEEK_SET);
+ if (result == -1) {
+ close(buffer->data_file);
+ buffer->data_file = 0;
+ buffer->data = NULL;
+ DBG(DBG_error, "sanei_pieusb_buffer_create(): error calling lseek() to 'stretch' the file to %d bytes\n", buffer_size_bytes-1);
+ perror("sanei_pieusb_buffer_create(): error calling lseek()");
+ return SANE_STATUS_INVAL;
+ }
+ /* Write one byte at the end */
+ g = 0x00;
+ result = write(buffer->data_file, &g, 1);
+ if (result < 0) {
+ close(buffer->data_file);
+ buffer->data_file = 0;
+ buffer->data = NULL;
+ perror("sanei_pieusb_buffer_create(): error writing a byte at the end of the file");
+ return SANE_STATUS_IO_ERROR;
+ }
+#ifdef HAVE_MMAP
+ /* Create memory map */
+ buffer->data = mmap(NULL, buffer_size_bytes, PROT_WRITE | PROT_READ, MAP_SHARED, buffer->data_file, 0);
+ if (buffer->data == MAP_FAILED) {
+ close(buffer->data_file);
+ buffer->data = NULL;
+ perror("sanei_pieusb_buffer_create(): error mapping file");
+ return SANE_STATUS_INVAL;
+ }
+#else
+#error mmap(2) not available, aborting
+#endif
+ buffer->data_size = buffer_size_bytes;
+ /* Reading and writing */
+ buffer->p_read = calloc(buffer->colors, sizeof(SANE_Uint*));
+ if (buffer->p_read == NULL)
+ return SANE_STATUS_NO_MEM;
+ buffer->p_write = calloc(buffer->colors, sizeof(SANE_Uint*));
+ if (buffer->p_write == NULL)
+ return SANE_STATUS_NO_MEM;
+ for (k = 0; k < buffer->colors; k++) {
+ buffer->p_write[k] = buffer->data + k * buffer->height * buffer->width;
+ buffer->p_read[k] = buffer->p_write[k];
+ }
+ buffer->read_index[0] = 0;
+ buffer->read_index[1] = 0;
+ buffer->read_index[2] = 0;
+ buffer->read_index[3] = 0;
+
+ /* Statistics */
+ buffer->bytes_read = 0;
+ buffer->bytes_written = 0;
+ buffer->bytes_unread = 0;
+
+ DBG(DBG_info,"pieusb: Read buffer created: w=%d h=%d ncol=%d depth=%d in file %s\n",
+ buffer->width, buffer->height, buffer->colors, buffer->depth, buffer->buffer_name);
+ return SANE_STATUS_GOOD;
+}
+
+/**
+ * Delete buffer and free its resources
+ *
+ * @param buffer
+ */
+void
+sanei_pieusb_buffer_delete(struct Pieusb_Read_Buffer* buffer)
+{
+#ifdef HAVE_MMAP
+ munmap(buffer->data, buffer->data_size);
+#else
+#error mmap(2) not available, aborting
+#endif
+ /* ftruncate(buffer->data_file,0); Can we delete given a file-descriptor? */
+ close(buffer->data_file);
+ /* remove fs entry */
+ unlink(buffer->buffer_name);
+ buffer->data_file = 0;
+ buffer->data_size = 0;
+ free(buffer->p_read);
+ free(buffer->p_write);
+ buffer->data = 0;
+ buffer->width = 0;
+ buffer->height = 0;
+ buffer->depth = 0;
+ buffer->colors = 0;
+ buffer->packing_density = 0;
+
+ DBG(DBG_info,"pieusb: Read buffer deleted\n");
+}
+
+/**
+ * Add a line to the reader buffer, for the given color.
+ * The buffer checks and decides how to interpret the data.
+ *
+ * @param buffer
+ * @param color Color code for line
+ * @param line
+ * @param size Number of bytes in line
+ * @return 1 if successful, 0 if not
+ */
+SANE_Int
+sanei_pieusb_buffer_put_single_color_line(struct Pieusb_Read_Buffer* buffer, SANE_Byte color, void* line, SANE_Int size)
+{
+
+ SANE_Int c, k, m, n;
+
+ /* Check index code */
+ c = -1;
+ switch (color) {
+ case 'R':
+ c = buffer->color_index_red;
+ break;
+ case 'G':
+ c = buffer->color_index_green;
+ break;
+ case 'B':
+ c = buffer->color_index_blue;
+ break;
+ case 'I':
+ c = buffer->color_index_infrared;
+ break;
+ }
+ if (c == -1) {
+ DBG(DBG_error, "sanei_pieusb_buffer_put_single_color_line(): color '%c' not specified when buffer was created\n", color);
+ return 0;
+ }
+ DBG(DBG_info_buffer, "sanei_pieusb_buffer_put_single_color_line() line color = %d (0=R, 1=G, 2=B, 3=I)\n",c);
+
+ /* Check line size (for a line with a single color) */
+ if (buffer->line_size_bytes != size) {
+ DBG(DBG_error, "sanei_pieusb_buffer_put_single_color_line(): incorrect line size, expecting %d, got %d\n", buffer->line_size_bytes, size);
+ return 0;
+ }
+
+ /* The general approach for all densities and packet sizes
+ * - process packet_size_bytes at a time
+ * - use packing_density to decode the full packet into separate values
+ * - now save these values as neighbouring pixels on the current line
+ * Use custom code for the 1-byte and 2-byte single sample cases,
+ * because the general approach is a bit overkill for them.
+ */
+
+ if (buffer->packet_size_bytes == 1 && buffer->packing_density == 1) {
+ uint8_t* p_packet = (uint8_t*)line;
+ n = 0;
+ while (n < size) {
+ /* Get next packet data & store in buffer */
+ *buffer->p_write[c]++ = *p_packet++;
+ n++;
+ }
+ } else if (buffer->packet_size_bytes == 2 && buffer->packing_density == 1) {
+ uint16_t* p_packet = (uint16_t*)line;
+ n = 0;
+ while (n < size) {
+ /* Get next packet data & store in buffer */
+ *buffer->p_write[c]++ = le16toh (*p_packet++);
+ n += 2;
+ }
+ } else {
+ uint8_t* p_packet = (uint8_t*)line;
+ uint8_t *packet = (uint8_t *)alloca(buffer->packet_size_bytes * sizeof(uint8_t));
+ SANE_Uint val;
+ uint8_t mask = ~(0xFF >> buffer->depth); /* byte with depth most significant bits set */
+ n = 0;
+ while (n < size) {
+ /* Get next packet data */
+ for (k = 0; k < buffer->packet_size_bytes; k++) packet[k] = *p_packet++;
+ /* Unpack packing_density samples from packet. Of course,
+ * buffer->depth * packing_density <= # bits in packet.
+ * That is checked at buffer creation. */
+ for (k = 0; k < buffer->packing_density; k++) {
+ /* Take 1st depth bits and store in val */
+ val = (packet[0] & mask) >> (8-buffer->depth);
+ /* Now shift packet bytes depth bits left */
+ for (m = 0; m < buffer->packet_size_bytes; m++) {
+ /* Shift left one sample */
+ packet[m] <<= buffer->depth;
+ if (m < buffer->packet_size_bytes-1) {
+ /* If there are more bytes, insert 1st depth bits of next byte */
+ packet[m] |= (packet[m+1] >> (8-buffer->depth));
+ }
+ }
+ /* Store in buffer */
+ *buffer->p_write[c]++ = val;
+ }
+ n += buffer->packet_size_bytes;
+ }
+ }
+
+ /* Update state & statistics */
+ buffer->bytes_written += size;
+ buffer->bytes_unread += size;
+
+ /* Output current buffer state */
+ /* buffer_output_state(buffer); */
+
+ return 1;
+}
+
+/**
+ * Write line of full color pixels to the buffer.
+ *
+ * @param buffer Read buffer
+ * @param pixel array of full color pixel data
+ * @param size Number of bytes in the line
+ * @return 1 if successful, 0 if not
+ */
+/**
+ *
+ */
+SANE_Int
+sanei_pieusb_buffer_put_full_color_line(struct Pieusb_Read_Buffer* buffer, void* line, int size)
+{
+ int k, c, m, n;
+
+ DBG(DBG_info_buffer, "sanei_pieusb_buffer_put_full_color_line() entered\n");
+
+ /* Check line size */
+ if (buffer->line_size_bytes * buffer->colors != size) {
+ DBG(DBG_error, "sanei_pieusb_buffer_put_full_color_line(): incorrect line size, expecting %d, got %d\n", buffer->line_size_bytes * buffer->colors, size);
+ return 0;
+ }
+
+ /* The general approach for all densities and packet sizes
+ * - process packet_size_bytes at a time
+ * - use packing_density to decode the full packet into separate values
+ * - now save these values as neighbouring pixels on the current line
+ * Use custom code for the 1-byte and 2-byte single sample cases,
+ * because the general approach is a bit overkill for them.
+ */
+
+ if (buffer->packet_size_bytes == 1 && buffer->packing_density == 1) {
+ uint8_t* p_packet = (uint8_t*)line;
+ n = 0;
+ while (n < size) {
+ /* Get next packet data & store in buffer */
+ for (c = 0; c < buffer->colors; c++) {
+ *buffer->p_write[c]++ = *p_packet++;
+ n++;
+ }
+ }
+ } else if (buffer->packet_size_bytes == 2 && buffer->packing_density == 1) {
+ uint16_t* p_packet = (uint16_t*)line;
+ n = 0;
+ while (n < size) {
+ /* Get next packet data & store in buffer */
+ for (c = 0; c < buffer->colors; c++) {
+ *buffer->p_write[c]++ = le16toh (*p_packet++);
+ n += 2;
+ }
+ }
+ } else {
+ uint8_t* p_packet = (uint8_t*)line;
+ uint8_t *packet = (uint8_t *)alloca(buffer->packet_size_bytes * sizeof(uint8_t));
+ SANE_Uint val;
+ uint8_t mask = ~(0xFF >> buffer->depth); /* byte with depth most significant bits set */
+ /* DBG(DBG_info,"buffer_put_full_color_line(): mask %02x\n",mask); */
+ n = 0;
+ while (n < size) {
+ /* Get next packet data */
+ for (c = 0; c < buffer->colors; c++) {
+ for (k = 0; k < buffer->packet_size_bytes; k++) {
+ packet[k] = *p_packet++;
+ /* DBG(DBG_info,"buffer_put_full_color_line(): packet[%d] = %02x\n",k,packet[k]); */
+ }
+ /* Unpack packing_density samples from packet. Of course,
+ * buffer->depth * packing_density <= # bits in packet.
+ * That is checked at buffer creation. */
+ for (k = 0; k < buffer->packing_density; k++) {
+ /* Take 1st depth bits and store in val */
+ val = (packet[0] & mask) >> (8-buffer->depth);
+ /* DBG(DBG_info,"buffer_put_full_color_line(): val[%d] = %02x\n",k,val); */
+ /* Now shift packet bytes depth bits left */
+ for (m = 0; m < buffer->packet_size_bytes; m++) {
+ /* Shift left one sample */
+ packet[m] <<= buffer->depth;
+ /* DBG(DBG_info,"buffer_put_full_color_line(): shift packet[%d] = %02x\n",m,packet[m]); */
+ if (m < buffer->packet_size_bytes-1) {
+ /* If there are more bytes, insert 1st depth bits of next byte */
+ packet[m] |= (packet[m+1] >> (8-buffer->depth));
+ /* DBG(DBG_info,"buffer_put_full_color_line(): shift packet[%d] = %02x\n",m,packet[m]); */
+ }
+ }
+ /* Store in buffer */
+ *buffer->p_write[c]++ = val;
+ }
+ n += buffer->packet_size_bytes;
+ }
+ }
+ }
+
+ /* Update state & statistics */
+ buffer->bytes_written += size;
+ buffer->bytes_unread += size;
+
+ /* Output current buffer state */
+ /* buffer_output_state(buffer); */
+
+ return 1;
+}
+
+/**
+ * Return bytes from the buffer. Do not mind pixel boundaries.
+ * Since the image data is organized in color planes, return bytes from the
+ * planes in the defined order. Take care to return multi-byte values after
+ * each other. Pack unpacked values.
+ *
+ * @param buffer Buffer to return bytes from.
+ * @param data Byte array to return bytes in
+ * @param max_len Maximum number of bytes returned
+ * @param len Actual number of bytes returned
+ */
+void
+sanei_pieusb_buffer_get(struct Pieusb_Read_Buffer* buffer, SANE_Byte* data, SANE_Int max_len, SANE_Int* len)
+{
+ SANE_Byte *pdata;
+ SANE_Int n, i, n_bits, N;
+
+ DBG(DBG_info_buffer, "sanei_pieusb_buffer_get() entered\n");
+
+ /* Read from the p_read locations */
+ pdata = data;
+ n = 0;
+ N = buffer->width * buffer->height;
+ /* Determine bytes to return */
+ if (buffer->packet_size_bytes == 1 && buffer->packing_density == 1) {
+ /* Single byte values in buffer */
+ while (n < max_len && buffer->bytes_read < buffer->image_size_bytes) {
+ /* Return byte*/
+ *pdata++ = *(buffer->data + N*buffer->read_index[0] + buffer->width*buffer->read_index[1] + buffer->read_index[2]) & 0xFF;
+ /* Update read indices */
+ buffer_update_read_index(buffer,1);
+ /* Update number of bytes read */
+ buffer->bytes_read++;
+ n++;
+ }
+ } else if (buffer->packet_size_bytes == 1 && buffer->packing_density == 8) {
+ /* Unpacked bits in buffer: repack */
+ while (n < max_len && buffer->bytes_read < buffer->image_size_bytes) {
+ uint8_t val = 0;
+ /* How many bits to pack? At the end of a line it may be less than 8 */
+ n_bits = 8;
+ if (buffer->width - buffer->read_index[2] < 8) {
+ n_bits = buffer->width - buffer->read_index[2];
+ }
+ /* Pack n_bits samples from same color plane */
+ for (i = 0; i < n_bits; i++) {
+ if (*(buffer->data + N*buffer->read_index[0] + buffer->width*buffer->read_index[1] + buffer->read_index[2] + i) > 0) {
+ val |= (0x80 >> i);
+ }
+ }
+ /* Return byte */
+ *pdata++ = val;
+ /* Update read indices */
+ buffer_update_read_index(buffer,n_bits);
+ /* Update number of bytes read */
+ buffer->bytes_read++;
+ n++;
+ }
+ } else if (buffer->packet_size_bytes == 2) {
+ /* Two-byte values in buffer */
+ while (n < max_len && buffer->bytes_read < buffer->image_size_bytes) {
+ /* Pointer to byte to return */
+ SANE_Uint val = *(buffer->data + N*buffer->read_index[0] + buffer->width*buffer->read_index[1] + buffer->read_index[2]);
+ /* Return byte */
+ if (buffer->read_index[3] == 0) {
+ *pdata++ = *((SANE_Byte*)(&val));
+ } else {
+ *pdata++ = *((SANE_Byte*)(&val)+1);
+ }
+ /* Update read indices */
+ buffer_update_read_index(buffer,1);
+ /* Update number of bytes read */
+ buffer->bytes_read++;
+ n++;
+ }
+ } else {
+ /* not implemented */
+ DBG(DBG_error, "buffer_put(): paccket size & density of %d/%d not implementd\n", buffer->packet_size_bytes, buffer->packing_density);
+ return;
+ }
+ *len = n;
+
+ /* Update statistics */
+ buffer->bytes_unread -= n;
+
+ /* Output current buffer state */
+ /* buffer_output_state(buffer); */
+}
+
+/**
+ * Update read index to point a given number of bytes past the current position.
+ *
+ * @param buffer the buffer to initialize
+ * @param increment the amount of bytes to move the index
+ */
+static void buffer_update_read_index(struct Pieusb_Read_Buffer* buffer, int increment)
+{
+ /* Update read indices
+ * [3] = byte-index in 2-byte value: increased first, if we have 2-byte data
+ * [2] = index of pixel on line: increased after color plane
+ * [1] = index of line: increased after line is complete
+ * [0] = color index: increased first since SANE requires full color pixels */
+ if (buffer->read_index[3] == 0 && buffer->packet_size_bytes == 2) {
+ buffer->read_index[3] = 1;
+ } else {
+ buffer->read_index[3] = 0;
+ buffer->read_index[0]++;
+ if (buffer->read_index[0] == buffer->colors) {
+ buffer->read_index[0] = 0;
+ buffer->read_index[2] += increment;
+ if (buffer->read_index[2] >= buffer->width) {
+ buffer->read_index[2] = 0;
+ buffer->read_index[1]++;
+ }
+ }
+ }
+}
+
+#if 0
+/**
+ * Display the buffer state.
+ *
+ * @param buffer the buffer to initialize
+ */
+
+static void buffer_output_state(struct Pieusb_Read_Buffer* buffer)
+{
+ SANE_Int line_size;
+ SANE_Int N, k, loc[4];
+
+ line_size = buffer->line_size_bytes * buffer->colors; /* Full line size in bytes */
+
+ DBG(DBG_info_buffer, "Buffer data\n");
+ DBG(DBG_info_buffer," width/height/colors/depth = %d %d %d %d (buffer size %d)\n",
+ buffer->width, buffer->height, buffer->colors, buffer->depth, buffer->image_size_bytes);
+
+ /* Summary */
+ N = buffer->width * buffer->height;
+ for (k = 0; k < buffer->colors; k++) {
+ loc[k] = buffer->p_read[k] - buffer->data - k*N;
+ }
+ for (k = buffer->colors; k < 4; k++) {
+ loc[k] = 0;
+ }
+ DBG(DBG_info_buffer, " reading at: lines = %d:%d:%d:%d\n", loc[0], loc[1], loc[2], loc[3]);
+ for (k = 0; k < buffer->colors; k++) {
+ loc[k] = buffer->p_write[k] - buffer->data - k*N;
+ }
+ for (k = buffer->colors; k < 4; k++) {
+ loc[k] = 0;
+ }
+ DBG(DBG_info_buffer, " writing at: lines = %d:%d:%d:%d\n", loc[0], loc[1], loc[2], loc[3]);
+
+ /* Progress */
+ double fdata = (double)buffer->bytes_unread/buffer->image_size_bytes*100;
+ double fread = (double)buffer->bytes_read/buffer->image_size_bytes*100;
+ double fwritten = (double)buffer->bytes_written/buffer->image_size_bytes*100;
+ DBG(DBG_info_buffer, " byte counts: image = %d, data = %d (%.0f%%), read = %d (%.0f%%), written = %d (%.0f%%)\n",
+ buffer->image_size_bytes, buffer->bytes_unread, fdata, buffer->bytes_read, fread, buffer->bytes_written, fwritten);
+ DBG(DBG_info_buffer, " line counts: image = %.1f, data = %.1f, read = %.1f, written = %.1f\n",
+ (double)buffer->image_size_bytes/line_size, (double)buffer->bytes_unread/line_size, (double)buffer->bytes_read/line_size, (double)buffer->bytes_written/line_size);
+
+}
+#endif