Initial check-in
This commit is contained in:
Philip Heron
commit
50eeaf77e5
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@ -0,0 +1,14 @@
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CC=gcc
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CFLAGS=-g -Wall
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LDFLAGS=-g
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ssdv: main.o ssdv.o rs8.o
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$(CC) $(LDFLAGS) main.o ssdv.o rs8.o -o ssdv
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.c.o:
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$(CC) $(CFLAGS) -c $< -o $@
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clean:
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rm *.o
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@ -0,0 +1,154 @@
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#include <stdio.h>
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#include <stdint.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <string.h>
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#include "ssdv.h"
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void exit_usage()
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{
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fprintf(stderr, "Usage: ssdv [-e|-d] [-t <percentage>] [-i <id>] [<in file>] [<out file>]\n");
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exit(-1);
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}
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int main(int argc, char *argv[])
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{
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int c, i;
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FILE *fin = stdin;
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FILE *fout = stdout;
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char encode = -1;
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int droptest = 0;
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uint8_t image_id = 0;
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ssdv_t ssdv;
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uint8_t pkt[SSDV_PKT_SIZE], b[128], *jpeg;
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size_t jpeg_length;
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opterr = 0;
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while((c = getopt(argc, argv, "edi:t:")) != -1)
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{
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switch(c)
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{
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case 'e': encode = 1; break;
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case 'd': encode = 0; break;
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case 'i': image_id = atoi(optarg); break;
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case 't': droptest = atoi(optarg); break;
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case '?': exit_usage();
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}
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}
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c = argc - optind;
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if(c > 2) exit_usage();
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for(i = 0; i < c; i++)
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{
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if(!strcmp(argv[optind + i], "-")) continue;
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switch(i)
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{
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case 0:
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fin = fopen(argv[optind + i], "rb");
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if(!fin)
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{
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fprintf(stderr, "Error opening '%s' for input:\n", argv[optind + i]);
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perror("fopen");
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return(-1);
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}
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break;
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case 1:
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fout = fopen(argv[optind + i], "wb");
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if(!fout)
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{
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fprintf(stderr, "Error opening '%s' for output:\n", argv[optind + i]);
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perror("fopen");
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return(-1);
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}
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break;
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}
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}
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switch(encode)
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{
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case 0: /* Decode */
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if(droptest > 0) fprintf(stderr, "*** NOTE: Drop test enabled: %i ***\n", droptest);
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ssdv_dec_init(&ssdv);
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jpeg_length = 1024 * 1024 * 4;
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jpeg = malloc(jpeg_length);
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ssdv_dec_set_buffer(&ssdv, jpeg, jpeg_length);
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i = 0;
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while(fread(pkt, 1, SSDV_PKT_SIZE, fin) > 0)
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{
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/* Drop % of packets */
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if(droptest && (rand() / (RAND_MAX / 100) < droptest)) continue;
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/* Test the packet is valid */
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if(ssdv_dec_is_packet(pkt, NULL) != 0) continue;
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/* Feed it to the decoder */
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ssdv_dec_feed(&ssdv, pkt);
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i++;
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}
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ssdv_dec_get_jpeg(&ssdv, &jpeg, &jpeg_length);
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fwrite(jpeg, 1, jpeg_length, fout);
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free(jpeg);
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fprintf(stderr, "Read %i packets\n", i);
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break;
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case 1: /* Encode */
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ssdv_enc_init(&ssdv, image_id);
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ssdv_enc_set_buffer(&ssdv, pkt);
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i = 0;
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while(1)
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{
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while((c = ssdv_enc_get_packet(&ssdv)) == SSDV_FEED_ME)
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{
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size_t r = fread(b, 1, 128, fin);
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if(r <= 0)
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{
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fprintf(stderr, "Premature end of file\n");
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break;
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}
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ssdv_enc_feed(&ssdv, b, r);
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}
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if(c == SSDV_EOI)
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{
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fprintf(stderr, "ssdv_enc_get_packet said EOI\n");
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break;
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}
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else if(c != SSDV_OK)
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{
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fprintf(stderr, "ssdv_enc_get_packet failed: %i\n", c);
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return(-1);
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}
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fwrite(pkt, 1, SSDV_PKT_SIZE, fout);
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i++;
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}
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fprintf(stderr, "Wrote %i packets\n", i);
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break;
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default:
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fprintf(stderr, "No mode specified.\n");
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break;
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}
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if(fin != stdin) fclose(fin);
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if(fout != stdout) fclose(fout);
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return(0);
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}
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@ -0,0 +1,318 @@
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/* General purpose Reed-Solomon codec for 8-bit symbols or less
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* Copyright 2003 Phil Karn, KA9Q
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* May be used under the terms of the GNU Lesser General Public License (LGPL)
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*
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* This version tweaked by Philip Heron <phil@sanslogic.co.uk>
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*/
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#include <string.h>
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#include "rs8.h"
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static const uint8_t ALPHA_TO[] = {
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0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80,0x87,0x89,0x95,0xAD,0xDD,0x3D,0x7A,0xF4,
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0x6F,0xDE,0x3B,0x76,0xEC,0x5F,0xBE,0xFB,0x71,0xE2,0x43,0x86,0x8B,0x91,0xA5,0xCD,
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0x1D,0x3A,0x74,0xE8,0x57,0xAE,0xDB,0x31,0x62,0xC4,0x0F,0x1E,0x3C,0x78,0xF0,0x67,
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0xCE,0x1B,0x36,0x6C,0xD8,0x37,0x6E,0xDC,0x3F,0x7E,0xFC,0x7F,0xFE,0x7B,0xF6,0x6B,
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0xD6,0x2B,0x56,0xAC,0xDF,0x39,0x72,0xE4,0x4F,0x9E,0xBB,0xF1,0x65,0xCA,0x13,0x26,
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0x4C,0x98,0xB7,0xE9,0x55,0xAA,0xD3,0x21,0x42,0x84,0x8F,0x99,0xB5,0xED,0x5D,0xBA,
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0xF3,0x61,0xC2,0x03,0x06,0x0C,0x18,0x30,0x60,0xC0,0x07,0x0E,0x1C,0x38,0x70,0xE0,
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0x47,0x8E,0x9B,0xB1,0xE5,0x4D,0x9A,0xB3,0xE1,0x45,0x8A,0x93,0xA1,0xC5,0x0D,0x1A,
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0x34,0x68,0xD0,0x27,0x4E,0x9C,0xBF,0xF9,0x75,0xEA,0x53,0xA6,0xCB,0x11,0x22,0x44,
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0x88,0x97,0xA9,0xD5,0x2D,0x5A,0xB4,0xEF,0x59,0xB2,0xE3,0x41,0x82,0x83,0x81,0x85,
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0x8D,0x9D,0xBD,0xFD,0x7D,0xFA,0x73,0xE6,0x4B,0x96,0xAB,0xD1,0x25,0x4A,0x94,0xAF,
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0xD9,0x35,0x6A,0xD4,0x2F,0x5E,0xBC,0xFF,0x79,0xF2,0x63,0xC6,0x0B,0x16,0x2C,0x58,
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0xB0,0xE7,0x49,0x92,0xA3,0xC1,0x05,0x0A,0x14,0x28,0x50,0xA0,0xC7,0x09,0x12,0x24,
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0x48,0x90,0xA7,0xC9,0x15,0x2A,0x54,0xA8,0xD7,0x29,0x52,0xA4,0xCF,0x19,0x32,0x64,
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0xC8,0x17,0x2E,0x5C,0xB8,0xF7,0x69,0xD2,0x23,0x46,0x8C,0x9F,0xB9,0xF5,0x6D,0xDA,
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0x33,0x66,0xCC,0x1F,0x3E,0x7C,0xF8,0x77,0xEE,0x5B,0xB6,0xEB,0x51,0xA2,0xC3,0x00,
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};
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static const uint8_t INDEX_OF[] = {
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0xFF,0x00,0x01,0x63,0x02,0xC6,0x64,0x6A,0x03,0xCD,0xC7,0xBC,0x65,0x7E,0x6B,0x2A,
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0x04,0x8D,0xCE,0x4E,0xC8,0xD4,0xBD,0xE1,0x66,0xDD,0x7F,0x31,0x6C,0x20,0x2B,0xF3,
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0x05,0x57,0x8E,0xE8,0xCF,0xAC,0x4F,0x83,0xC9,0xD9,0xD5,0x41,0xBE,0x94,0xE2,0xB4,
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0x67,0x27,0xDE,0xF0,0x80,0xB1,0x32,0x35,0x6D,0x45,0x21,0x12,0x2C,0x0D,0xF4,0x38,
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0x06,0x9B,0x58,0x1A,0x8F,0x79,0xE9,0x70,0xD0,0xC2,0xAD,0xA8,0x50,0x75,0x84,0x48,
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0xCA,0xFC,0xDA,0x8A,0xD6,0x54,0x42,0x24,0xBF,0x98,0x95,0xF9,0xE3,0x5E,0xB5,0x15,
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0x68,0x61,0x28,0xBA,0xDF,0x4C,0xF1,0x2F,0x81,0xE6,0xB2,0x3F,0x33,0xEE,0x36,0x10,
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0x6E,0x18,0x46,0xA6,0x22,0x88,0x13,0xF7,0x2D,0xB8,0x0E,0x3D,0xF5,0xA4,0x39,0x3B,
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0x07,0x9E,0x9C,0x9D,0x59,0x9F,0x1B,0x08,0x90,0x09,0x7A,0x1C,0xEA,0xA0,0x71,0x5A,
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0xD1,0x1D,0xC3,0x7B,0xAE,0x0A,0xA9,0x91,0x51,0x5B,0x76,0x72,0x85,0xA1,0x49,0xEB,
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0xCB,0x7C,0xFD,0xC4,0xDB,0x1E,0x8B,0xD2,0xD7,0x92,0x55,0xAA,0x43,0x0B,0x25,0xAF,
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0xC0,0x73,0x99,0x77,0x96,0x5C,0xFA,0x52,0xE4,0xEC,0x5F,0x4A,0xB6,0xA2,0x16,0x86,
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0x69,0xC5,0x62,0xFE,0x29,0x7D,0xBB,0xCC,0xE0,0xD3,0x4D,0x8C,0xF2,0x1F,0x30,0xDC,
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0x82,0xAB,0xE7,0x56,0xB3,0x93,0x40,0xD8,0x34,0xB0,0xEF,0x26,0x37,0x0C,0x11,0x44,
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0x6F,0x78,0x19,0x9A,0x47,0x74,0xA7,0xC1,0x23,0x53,0x89,0xFB,0x14,0x5D,0xF8,0x97,
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0x2E,0x4B,0xB9,0x60,0x0F,0xED,0x3E,0xE5,0xF6,0x87,0xA5,0x17,0x3A,0xA3,0x3C,0xB7,
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};
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static const uint8_t GENPOLY[] = {
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0x00,0xF9,0x3B,0x42,0x04,0x2B,0x7E,0xFB,0x61,0x1E,0x03,0xD5,0x32,0x42,0xAA,0x05,
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0x18,0x05,0xAA,0x42,0x32,0xD5,0x03,0x1E,0x61,0xFB,0x7E,0x2B,0x04,0x42,0x3B,0xF9,
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0x00,
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};
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static inline int mod255(int x)
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{
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while(x >= 255)
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{
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x -= 255;
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x = (x >> 8) + (x & 255);
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}
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return(x);
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}
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#define MODNN(x) mod255(x)
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#define MM (8)
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#define NN (255)
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#define NROOTS (32)
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#define FCR (112)
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#define PRIM (11)
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#define IPRIM (116)
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#define MIN(a,b) ((a) < (b) ? (a) : (b))
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#define A0 (NN) /* Special reserved value encoding zero in index form */
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/* Portable C version */
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void encode_rs_8(uint8_t *data, uint8_t *parity, int pad)
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{
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int i, j;
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uint8_t feedback;
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memset(parity, 0, NROOTS * sizeof(uint8_t));
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for(i = 0; i < NN - NROOTS - pad; i++)
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{
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feedback = INDEX_OF[data[i] ^ parity[0]];
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if(feedback != A0) /* feedback term is non-zero */
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{
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for(j = 1; j < NROOTS; j++)
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parity[j] ^= ALPHA_TO[mod255(feedback + GENPOLY[NROOTS - j])];
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||||||
|
}
|
||||||
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|
||||||
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/* Shift */
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memmove(&parity[0], &parity[1], sizeof(uint8_t) * (NROOTS - 1));
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if(feedback != A0)
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parity[NROOTS - 1] = ALPHA_TO[mod255(feedback + GENPOLY[0])];
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|
else
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parity[NROOTS - 1] = 0;
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|
}
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}
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||||||
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int decode_rs_8(uint8_t *data, int *eras_pos, int no_eras, int pad)
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||||||
|
{
|
||||||
|
int deg_lambda, el, deg_omega;
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||||||
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int i, j, r, k;
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||||||
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uint8_t u, q, tmp, num1, num2, den, discr_r;
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||||||
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uint8_t lambda[NROOTS + 1], s[NROOTS]; /* Err+Eras Locator poly
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* and syndrome poly */
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uint8_t b[NROOTS + 1], t[NROOTS + 1], omega[NROOTS + 1];
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uint8_t root[NROOTS], reg[NROOTS + 1], loc[NROOTS];
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int syn_error, count;
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||||||
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if(pad < 0 || pad > 222) return(-1);
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|
||||||
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/* form the syndromes; i.e., evaluate data(x) at roots of g(x) */
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for(i = 0; i < NROOTS; i++) s[i] = data[0];
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|
||||||
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for(j = 1; j < NN - pad; j++)
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{
|
||||||
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for(i = 0; i < NROOTS; i++)
|
||||||
|
{
|
||||||
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if(s[i] == 0) s[i] = data[j];
|
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else s[i] = data[j] ^ ALPHA_TO[MODNN(INDEX_OF[s[i]] + (FCR + i) * PRIM)];
|
||||||
|
}
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||||||
|
}
|
||||||
|
|
||||||
|
/* Convert syndromes to index form, checking for nonzero condition */
|
||||||
|
syn_error = 0;
|
||||||
|
for(i = 0; i < NROOTS; i++)
|
||||||
|
{
|
||||||
|
syn_error |= s[i];
|
||||||
|
s[i] = INDEX_OF[s[i]];
|
||||||
|
}
|
||||||
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|
||||||
|
if(!syn_error)
|
||||||
|
{
|
||||||
|
/* if syndrome is zero, data[] is a codeword and there are no
|
||||||
|
* errors to correct. So return data[] unmodified
|
||||||
|
*/
|
||||||
|
count = 0;
|
||||||
|
goto finish;
|
||||||
|
}
|
||||||
|
|
||||||
|
memset(&lambda[1], 0, NROOTS * sizeof(lambda[0]));
|
||||||
|
lambda[0] = 1;
|
||||||
|
|
||||||
|
if(no_eras > 0)
|
||||||
|
{
|
||||||
|
/* Init lambda to be the erasure locator polynomial */
|
||||||
|
lambda[1] = ALPHA_TO[MODNN(PRIM * (NN - 1 - eras_pos[0]))];
|
||||||
|
for(i = 1; i < no_eras; i++)
|
||||||
|
{
|
||||||
|
u = MODNN(PRIM * (NN - 1 - eras_pos[i]));
|
||||||
|
for(j = i + 1; j > 0; j--)
|
||||||
|
{
|
||||||
|
tmp = INDEX_OF[lambda[j - 1]];
|
||||||
|
if(tmp != A0) lambda[j] ^= ALPHA_TO[MODNN(u + tmp)];
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
}
|
||||||
|
|
||||||
|
for(i = 0; i < NROOTS + 1; i++)
|
||||||
|
b[i] = INDEX_OF[lambda[i]];
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Begin Berlekamp-Massey algorithm to determine error+erasure
|
||||||
|
* locator polynomial
|
||||||
|
*/
|
||||||
|
r = no_eras;
|
||||||
|
el = no_eras;
|
||||||
|
while(++r <= NROOTS) /* r is the step number */
|
||||||
|
{
|
||||||
|
/* Compute discrepancy at the r-th step in poly-form */
|
||||||
|
discr_r = 0;
|
||||||
|
for(i = 0; i < r; i++)
|
||||||
|
{
|
||||||
|
if((lambda[i] != 0) && (s[r - i - 1] != A0))
|
||||||
|
{
|
||||||
|
discr_r ^= ALPHA_TO[MODNN(INDEX_OF[lambda[i]] + s[r - i - 1])];
|
||||||
|
}
|
||||||
|
}
|
||||||
|
discr_r = INDEX_OF[discr_r]; /* Index form */
|
||||||
|
if(discr_r == A0)
|
||||||
|
{
|
||||||
|
/* 2 lines below: B(x) <-- x*B(x) */
|
||||||
|
memmove(&b[1], b, NROOTS * sizeof(b[0]));
|
||||||
|
b[0] = A0;
|
||||||
|
}
|
||||||
|
else
|
||||||
|
{
|
||||||
|
/* 7 lines below: T(x) <-- lambda(x) - discr_r*x*b(x) */
|
||||||
|
t[0] = lambda[0];
|
||||||
|
for(i = 0; i < NROOTS; i++)
|
||||||
|
{
|
||||||
|
if(b[i] != A0)
|
||||||
|
t[i + 1] = lambda[i + 1] ^ ALPHA_TO[MODNN(discr_r + b[i])];
|
||||||
|
else
|
||||||
|
t[i + 1] = lambda[i + 1];
|
||||||
|
}
|
||||||
|
|
||||||
|
if(2 * el <= r + no_eras - 1)
|
||||||
|
{
|
||||||
|
el = r + no_eras - el;
|
||||||
|
/*
|
||||||
|
* 2 lines below: B(x) <-- inv(discr_r) *
|
||||||
|
* lambda(x)
|
||||||
|
*/
|
||||||
|
for(i = 0; i <= NROOTS; i++)
|
||||||
|
b[i] = (lambda[i] == 0) ? A0 : MODNN(INDEX_OF[lambda[i]] - discr_r + NN);
|
||||||
|
}
|
||||||
|
else
|
||||||
|
{
|
||||||
|
/* 2 lines below: B(x) <-- x*B(x) */
|
||||||
|
memmove(&b[1], b, NROOTS * sizeof(b[0]));
|
||||||
|
b[0] = A0;
|
||||||
|
}
|
||||||
|
|
||||||
|
memcpy(lambda, t, (NROOTS + 1) * sizeof(t[0]));
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Convert lambda to index form and compute deg(lambda(x)) */
|
||||||
|
deg_lambda = 0;
|
||||||
|
for(i = 0; i < NROOTS + 1; i++)
|
||||||
|
{
|
||||||
|
lambda[i] = INDEX_OF[lambda[i]];
|
||||||
|
if(lambda[i] != A0) deg_lambda = i;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Find roots of the error+erasure locator polynomial by Chien search */
|
||||||
|
memcpy(®[1], &lambda[1], NROOTS * sizeof(reg[0]));
|
||||||
|
count = 0; /* Number of roots of lambda(x) */
|
||||||
|
for(i = 1, k = IPRIM - 1; i <= NN; i++, k = MODNN(k + IPRIM))
|
||||||
|
{
|
||||||
|
q = 1; /* lambda[0] is always 0 */
|
||||||
|
for(j = deg_lambda; j > 0; j--)
|
||||||
|
{
|
||||||
|
if(reg[j] != A0)
|
||||||
|
{
|
||||||
|
reg[j] = MODNN(reg[j] + j);
|
||||||
|
q ^= ALPHA_TO[reg[j]];
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
if (q != 0) continue; /* Not a root */
|
||||||
|
|
||||||
|
/* store root (index-form) and error location number */
|
||||||
|
root[count] = i;
|
||||||
|
loc[count] = k;
|
||||||
|
/* If we've already found max possible roots,
|
||||||
|
* abort the search to save time
|
||||||
|
*/
|
||||||
|
if(++count == deg_lambda) break;
|
||||||
|
}
|
||||||
|
|
||||||
|
if(deg_lambda != count)
|
||||||
|
{
|
||||||
|
/*
|
||||||
|
* deg(lambda) unequal to number of roots => uncorrectable
|
||||||
|
* error detected
|
||||||
|
*/
|
||||||
|
count = -1;
|
||||||
|
goto finish;
|
||||||
|
}
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Compute err+eras evaluator poly omega(x) = s(x)*lambda(x) (modulo
|
||||||
|
* x**NROOTS). in index form. Also find deg(omega).
|
||||||
|
*/
|
||||||
|
deg_omega = deg_lambda - 1;
|
||||||
|
for(i = 0; i <= deg_omega; i++)
|
||||||
|
{
|
||||||
|
tmp = 0;
|
||||||
|
for(j = i; j >= 0; j--)
|
||||||
|
{
|
||||||
|
if((s[i - j] != A0) && (lambda[j] != A0))
|
||||||
|
tmp ^= ALPHA_TO[MODNN(s[i - j] + lambda[j])];
|
||||||
|
}
|
||||||
|
omega[i] = INDEX_OF[tmp];
|
||||||
|
}
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Compute error values in poly-form. num1 = omega(inv(X(l))), num2 =
|
||||||
|
* inv(X(l))**(FCR-1) and den = lambda_pr(inv(X(l))) all in poly-form
|
||||||
|
*/
|
||||||
|
for(j = count - 1; j >= 0; j--)
|
||||||
|
{
|
||||||
|
num1 = 0;
|
||||||
|
for(i = deg_omega; i >= 0; i--)
|
||||||
|
{
|
||||||
|
if(omega[i] != A0) num1 ^= ALPHA_TO[MODNN(omega[i] + i * root[j])];
|
||||||
|
}
|
||||||
|
num2 = ALPHA_TO[MODNN(root[j] * (FCR - 1) + NN)];
|
||||||
|
den = 0;
|
||||||
|
|
||||||
|
/* lambda[i+1] for i even is the formal derivative lambda_pr of lambda[i] */
|
||||||
|
for(i = MIN(deg_lambda, NROOTS - 1) & ~1; i >= 0; i -= 2)
|
||||||
|
{
|
||||||
|
if(lambda[i + 1] != A0) den ^= ALPHA_TO[MODNN(lambda[i + 1] + i * root[j])];
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Apply error to data */
|
||||||
|
if(num1 != 0 && loc[j] >= pad)
|
||||||
|
{
|
||||||
|
data[loc[j] - pad] ^= ALPHA_TO[MODNN(INDEX_OF[num1] + INDEX_OF[num2] + NN - INDEX_OF[den])];
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
finish:
|
||||||
|
if(eras_pos != NULL)
|
||||||
|
{
|
||||||
|
for(i = 0; i < count; i++) eras_pos[i] = loc[i];
|
||||||
|
}
|
||||||
|
|
||||||
|
return(count);
|
||||||
|
}
|
||||||
|
|
||||||
|
|
@ -0,0 +1,23 @@
|
||||||
|
/* Reed-Solomon encoder
|
||||||
|
* Copyright 2004, Phil Karn, KA9Q
|
||||||
|
* May be used under the terms of the GNU Lesser General Public License (LGPL)
|
||||||
|
*
|
||||||
|
* This version tweaked by Philip Heron <phil@sanslogic.co.uk>
|
||||||
|
*/
|
||||||
|
|
||||||
|
#ifndef _RS8_H
|
||||||
|
#define _RS8_H
|
||||||
|
#ifdef __cplusplus
|
||||||
|
extern "C" {
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#include <stdint.h>
|
||||||
|
|
||||||
|
extern void encode_rs_8(uint8_t *data, uint8_t *parity, int pad);
|
||||||
|
extern int decode_rs_8(uint8_t *data, int *eras_pos, int no_eras, int pad);
|
||||||
|
|
||||||
|
#ifdef __cplusplus
|
||||||
|
}
|
||||||
|
#endif
|
||||||
|
#endif
|
||||||
|
|
||||||
|
|
@ -0,0 +1,116 @@
|
||||||
|
|
||||||
|
#include <stdint.h>
|
||||||
|
|
||||||
|
#ifndef INC_SSDV_H
|
||||||
|
#define INC_SSDV_H
|
||||||
|
#ifdef __cplusplus
|
||||||
|
extern "C" {
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#define SSDV_ERROR (-1)
|
||||||
|
#define SSDV_OK (0)
|
||||||
|
#define SSDV_FEED_ME (1)
|
||||||
|
#define SSDV_HAVE_PACKET (2)
|
||||||
|
#define SSDV_BUFFER_FULL (3)
|
||||||
|
#define SSDV_EOI (4)
|
||||||
|
|
||||||
|
/* Packet details */
|
||||||
|
#define SSDV_PKT_SIZE (0x100)
|
||||||
|
#define SSDV_PKT_SIZE_HEADER (0x0B)
|
||||||
|
#define SSDV_PKT_SIZE_CRC (0x02)
|
||||||
|
#define SSDV_PKT_SIZE_RSCODES (0x20)
|
||||||
|
#define SSDV_PKT_SIZE_PAYLOAD (SSDV_PKT_SIZE - SSDV_PKT_SIZE_HEADER - SSDV_PKT_SIZE_CRC - SSDV_PKT_SIZE_RSCODES)
|
||||||
|
|
||||||
|
#define HBUFF_LEN (16)
|
||||||
|
#define COMPONENTS (3)
|
||||||
|
|
||||||
|
typedef struct
|
||||||
|
{
|
||||||
|
/* Image information */
|
||||||
|
uint16_t width;
|
||||||
|
uint16_t height;
|
||||||
|
uint8_t image_id;
|
||||||
|
uint16_t packet_id;
|
||||||
|
uint16_t mcu_id;
|
||||||
|
uint16_t mcu_count;
|
||||||
|
uint16_t packet_mcu_id;
|
||||||
|
uint16_t packet_mcu_offset;
|
||||||
|
|
||||||
|
/* Source buffer */
|
||||||
|
uint8_t *inp; /* Pointer to next input byte */
|
||||||
|
size_t in_len; /* Number of input bytes remaining */
|
||||||
|
size_t in_skip; /* Number of input bytes to skip */
|
||||||
|
|
||||||
|
/* Source bits */
|
||||||
|
uint32_t workbits; /* Input bits currently being worked on */
|
||||||
|
uint8_t worklen; /* Number of bits in the input bit buffer */
|
||||||
|
|
||||||
|
/* JPEG / Packet output buffer */
|
||||||
|
uint8_t *out; /* Pointer to the beginning of the output buffer */
|
||||||
|
uint8_t *outp; /* Pointer to the next output byte */
|
||||||
|
size_t out_len; /* Number of output bytes remaining */
|
||||||
|
char out_stuff; /* Flag to add stuffing bytes to output */
|
||||||
|
|
||||||
|
/* Output bits */
|
||||||
|
uint32_t outbits; /* Output bit buffer */
|
||||||
|
uint8_t outlen; /* Number of bits in the output bit buffer */
|
||||||
|
|
||||||
|
/* JPEG decoder state */
|
||||||
|
enum {
|
||||||
|
S_MARKER = 0,
|
||||||
|
S_MARKER_LEN,
|
||||||
|
S_MARKER_DATA,
|
||||||
|
S_HUFF,
|
||||||
|
S_INT,
|
||||||
|
S_EOI,
|
||||||
|
} state;
|
||||||
|
uint16_t marker; /* Current marker */
|
||||||
|
uint16_t marker_len; /* Length of data following marker */
|
||||||
|
uint8_t *marker_data; /* Where to copy marker data too */
|
||||||
|
uint16_t marker_data_len; /* How much is there */
|
||||||
|
uint8_t component; /* 0 = Y, 1 = Cb, 2 = Cr */
|
||||||
|
uint8_t mcupart; /* 0-3 = Y, 4 = Cb, 5 = Cr */
|
||||||
|
uint8_t acpart; /* 0 - 64; 0 = DC, 1 - 64 = AC */
|
||||||
|
int dc[COMPONENTS]; /* DC value for each component */
|
||||||
|
uint8_t acrle; /* RLE value for current AC value */
|
||||||
|
char dcmode; /* 0 = Absolute, 1 = Relative (parts 0, 4 & 5) */
|
||||||
|
char needbits; /* Number of bits needed to decode integer */
|
||||||
|
|
||||||
|
/* Small buffer for reading SOF0 and SOS header data into */
|
||||||
|
uint8_t hbuff[HBUFF_LEN];
|
||||||
|
|
||||||
|
/* SSDV2 experiment */
|
||||||
|
int block[64];
|
||||||
|
|
||||||
|
} ssdv_t;
|
||||||
|
|
||||||
|
typedef struct {
|
||||||
|
uint8_t image_id;
|
||||||
|
uint16_t packet_id;
|
||||||
|
uint16_t width;
|
||||||
|
uint16_t height;
|
||||||
|
uint16_t mcu_offset;
|
||||||
|
uint16_t mcu_id;
|
||||||
|
uint16_t mcu_count;
|
||||||
|
} ssdv_packet_info_t;
|
||||||
|
|
||||||
|
/* Encoding */
|
||||||
|
extern char ssdv_enc_init(ssdv_t *s, uint8_t image_id);
|
||||||
|
extern char ssdv_enc_set_buffer(ssdv_t *s, uint8_t *buffer);
|
||||||
|
extern char ssdv_enc_get_packet(ssdv_t *s);
|
||||||
|
extern char ssdv_enc_feed(ssdv_t *s, uint8_t *buffer, size_t length);
|
||||||
|
|
||||||
|
/* Decoding */
|
||||||
|
extern char ssdv_dec_init(ssdv_t *s);
|
||||||
|
extern char ssdv_dec_set_buffer(ssdv_t *s, uint8_t *buffer, size_t length);
|
||||||
|
extern char ssdv_dec_feed(ssdv_t *s, uint8_t *packet);
|
||||||
|
extern char ssdv_dec_get_jpeg(ssdv_t *s, uint8_t **jpeg, size_t *length);
|
||||||
|
|
||||||
|
extern char ssdv_dec_is_packet(uint8_t *packet, int *errors);
|
||||||
|
extern void ssdv_dec_header(ssdv_packet_info_t *info, uint8_t *packet);
|
||||||
|
|
||||||
|
#ifdef __cplusplus
|
||||||
|
}
|
||||||
|
#endif
|
||||||
|
#endif
|
||||||
|
|
||||||
Loading…
Reference in New Issue