diff options
Diffstat (limited to 'v4l2-apps/libv4l/libv4lconvert/sq905c.c')
| -rw-r--r-- | v4l2-apps/libv4l/libv4lconvert/sq905c.c | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/v4l2-apps/libv4l/libv4lconvert/sq905c.c b/v4l2-apps/libv4l/libv4lconvert/sq905c.c new file mode 100644 index 000000000..2610e0317 --- /dev/null +++ b/v4l2-apps/libv4l/libv4lconvert/sq905c.c @@ -0,0 +1,217 @@ +/* + * sq905c.c + * + * Here is the decompression function for the SQ905C cameras. The functions + * used are adapted from the libgphoto2 functions for the same cameras, + * which was + * Copyright (c) 2005 and 2007 Theodore Kilgore <kilgota@auburn.edu> + * This version for libv4lconvert is + * Copyright (c) 2009 Theodore Kilgore <kilgota@auburn.edu> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as published by + * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser 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 + */ + +#include <stdlib.h> + +#include "libv4lconvert-priv.h" + + +#define CLIP(x) ((x) < 0 ? 0 : ((x) > 0xff) ? 0xff : (x)) + + +static int +sq905c_first_decompress(unsigned char *output, unsigned char *input, + unsigned int outputsize) +{ + unsigned char parity = 0; + unsigned char nibble_to_keep[2]; + unsigned char temp1 = 0, temp2 = 0; + unsigned char input_byte; + unsigned char lookup = 0; + unsigned int i = 0; + unsigned int bytes_used = 0; + unsigned int bytes_done = 0; + unsigned int bit_counter = 8; + unsigned int cycles = 0; + int table[9] = { -1, 0, 2, 6, 0x0e, 0x0e, 0x0e, 0x0e, 0xfb}; + unsigned char lookup_table[16] + = {0, 2, 6, 0x0e, 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, + 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0xfb}; + unsigned char translator[16] = {8, 7, 9, 6, 10, 11, 12, 13, + 14, 15, 5, 4, 3, 2, 1, 0}; + + nibble_to_keep[0] = 0; + nibble_to_keep[1] = 0; + + while (bytes_done < outputsize) { + while (parity < 2) { + while (lookup > table[cycles]) { + if (bit_counter == 8) { + input_byte = input[bytes_used]; + bytes_used++; + temp1 = input_byte; + bit_counter = 0; + } + input_byte = temp1; + temp2 = (temp2 << 1) & 0xFF; + input_byte = input_byte >> 7; + temp2 = temp2 | input_byte; + temp1 = (temp1 << 1) & 0xFF; + bit_counter++; + cycles++; + if (cycles > 9) + return -1; + lookup = temp2 & 0xff; + } + temp2 = 0; + for (i = 0; i < 17; i++) { + if (lookup == lookup_table[i]) { + nibble_to_keep[parity] = translator[i]; + break; + } + if (i == 16) + return -1; + } + cycles = 0; + parity++; + } + output[bytes_done] = (nibble_to_keep[0]<<4)|nibble_to_keep[1]; + bytes_done++; + parity = 0; + } + return 0; +} + +static int +sq905c_second_decompress(unsigned char *uncomp, unsigned char *in, + int width, int height) +{ + int diff = 0; + int tempval = 0; + int i, m, parity; + unsigned char delta_left = 0; + unsigned char delta_right = 0; + int input_counter = 0; + int delta_table[] = {-144, -110, -77, -53, -35, -21, -11, -3, + 2, 10, 20, 34, 52, 76, 110, 144}; + unsigned char *templine_red; + unsigned char *templine_green; + unsigned char *templine_blue; + templine_red = malloc(width); + if (!templine_red) { + free(templine_red); + return -1; + } + for (i = 0; i < width; i++) + templine_red[i] = 0x80; + templine_green = malloc(width); + if (!templine_green) { + free(templine_green); + return -1; + } + for (i = 0; i < width; i++) + templine_green[i] = 0x80; + templine_blue = malloc(width); + if (!templine_blue) { + free(templine_blue); + return -1; + } + for (i = 0; i < width; i++) + templine_blue[i] = 0x80; + for (m = 0; m < height/2; m++) { + /* First we do an even-numbered line */ + for (i = 0; i < width/2; i++) { + parity = i&1; + delta_right = in[input_counter] & 0x0f; + delta_left = (in[input_counter]>>4)&0xff; + input_counter++; + /* left pixel (red) */ + diff = delta_table[delta_left]; + if (!i) + tempval = templine_red[0] + diff; + else + tempval = (templine_red[i] + + uncomp[2*m*width+2*i-2])/2 + diff; + tempval = CLIP(tempval); + uncomp[2*m*width+2*i] = tempval; + templine_red[i] = tempval; + /* right pixel (green) */ + diff = delta_table[delta_right]; + if (!i) + tempval = templine_green[1] + diff; + else if (2*i == width - 2) + tempval = (templine_green[i] + + uncomp[2*m*width+2*i-1])/2 + + diff; + else + tempval = (templine_green[i+1] + + uncomp[2*m*width+2*i-1])/2 + + diff; + tempval = CLIP(tempval); + uncomp[2*m*width+2*i+1] = tempval; + templine_green[i] = tempval; + } + /* then an odd-numbered line */ + for (i = 0; i < width/2; i++) { + delta_right = in[input_counter] & 0x0f; + delta_left = (in[input_counter]>>4) & 0xff; + input_counter++; + /* left pixel (green) */ + diff = delta_table[delta_left]; + if (!i) + tempval = templine_green[0] + diff; + else + tempval = (templine_green[i] + + uncomp[(2*m+1)*width+2*i-2])/2 + + diff; + tempval = CLIP(tempval); + uncomp[(2*m+1)*width+2*i] = tempval; + templine_green[i] = tempval; + /* right pixel (blue) */ + diff = delta_table[delta_right]; + if (!i) + tempval = templine_blue[0] + diff; + else + tempval = (templine_blue[i] + + uncomp[(2*m+1)*width+2*i-1])/2 + + diff; + tempval = CLIP(tempval); + uncomp[(2*m+1)*width+2*i+1] = tempval; + templine_blue[i] = tempval; + } + } + free(templine_green); + free(templine_red); + free(templine_blue); + return 0; +} + +void v4lconvert_decode_sq905c(const unsigned char *src, unsigned char *dst, + int width, int height) +{ + int size; + unsigned char *temp_data; + unsigned char *raw; + /* here we get rid of the 0x50 bytes of header in src. */ + raw = src + 0x50; + size = width*height/2; + temp_data = malloc(size); + if (!temp_data) + goto out; + sq905c_first_decompress(temp_data, raw, size); + sq905c_second_decompress(dst, temp_data, width, height); +out: + free(temp_data); +} |