/* SSDV - Slow Scan Digital Video */ /*=======================================================================*/ /* Copyright 2011-2016 Philip Heron */ /* */ /* 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 3 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, see . */ #include #include #include #include "ssdv.h" #include "rs8.h" /* Recognised JPEG markers */ enum { J_TEM = 0xFF01, J_SOF0 = 0xFFC0, J_SOF1, J_SOF2, J_SOF3, J_DHT, J_SOF5, J_SOF6, J_SOF7, J_JPG, J_SOF9, J_SOF10, J_SOF11, J_DAC, J_SOF13, J_SOF14, J_SOF15, J_RST0, J_RST1, J_RST2, J_RST3, J_RST4, J_RST5, J_RST6, J_RST7, J_SOI, J_EOI, J_SOS, J_DQT, J_DNL, J_DRI, J_DHP, J_EXP, J_APP0, J_APP1, J_APP2, J_APP3, J_APP4, J_APP5, J_APP6, J_APP7, J_APP8, J_APP9, J_APP10, J_APP11, J_APP12, J_APP13, J_APP14, J_APP15, J_JPG0, J_JPG1, J_JPG2, J_JPG3, J_JPG4, J_JPG5, J_JPG6, J_SOF48, J_LSE, J_JPG9, J_JPG10, J_JPG11, J_JPG12, J_JPG13, J_COM, } jpeg_marker_t; /* APP0 header data */ static uint8_t const app0[14] = { 0x4A,0x46,0x49,0x46,0x00,0x01,0x01,0x01,0x00,0x48,0x00,0x48,0x00,0x00, }; /* SOS header data */ static uint8_t const sos[10] = { 0x03,0x01,0x00,0x02,0x11,0x03,0x11,0x00,0x3F,0x00, }; /* Quantisation table scaling factors for each quality level 0-7 */ static uint16_t const dqt_scales[8] = { 5000, 357, 172, 116, 100, 58, 28, 0 }; /* Quantisation tables */ static uint8_t const std_dqt0[65] = { 0x00,0x10,0x0C,0x0C,0x0E,0x0C,0x0A,0x10,0x0E,0x0E,0x0E,0x12,0x12,0x10,0x14,0x18, 0x28,0x1A,0x18,0x16,0x16,0x18,0x32,0x24,0x26,0x1E,0x28,0x3A,0x34,0x3E,0x3C,0x3A, 0x34,0x38,0x38,0x40,0x48,0x5C,0x4E,0x40,0x44,0x58,0x46,0x38,0x38,0x50,0x6E,0x52, 0x58,0x60,0x62,0x68,0x68,0x68,0x3E,0x4E,0x72,0x7A,0x70,0x64,0x78,0x5C,0x66,0x68, 0x64, }; static uint8_t const std_dqt1[65] = { 0x01,0x12,0x12,0x12,0x16,0x16,0x16,0x30,0x1A,0x1A,0x30,0x64,0x42,0x38,0x42,0x64, 0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64, 0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64, 0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64,0x64, 0x64, }; /* Standard Huffman tables */ static uint8_t const std_dht00[29] = { 0x00,0x00,0x01,0x05,0x01,0x01,0x01,0x01,0x01,0x01,0x00,0x00,0x00,0x00,0x00,0x00, 0x00,0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x0A,0x0B, }; static uint8_t const std_dht01[29] = { 0x01,0x00,0x03,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x00,0x00,0x00,0x00, 0x00,0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x0A,0x0B, }; static uint8_t const std_dht10[179] = { 0x10,0x00,0x02,0x01,0x03,0x03,0x02,0x04,0x03,0x05,0x05,0x04,0x04,0x00,0x00,0x01, 0x7D,0x01,0x02,0x03,0x00,0x04,0x11,0x05,0x12,0x21,0x31,0x41,0x06,0x13,0x51,0x61, 0x07,0x22,0x71,0x14,0x32,0x81,0x91,0xA1,0x08,0x23,0x42,0xB1,0xC1,0x15,0x52,0xD1, 0xF0,0x24,0x33,0x62,0x72,0x82,0x09,0x0A,0x16,0x17,0x18,0x19,0x1A,0x25,0x26,0x27, 0x28,0x29,0x2A,0x34,0x35,0x36,0x37,0x38,0x39,0x3A,0x43,0x44,0x45,0x46,0x47,0x48, 0x49,0x4A,0x53,0x54,0x55,0x56,0x57,0x58,0x59,0x5A,0x63,0x64,0x65,0x66,0x67,0x68, 0x69,0x6A,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7A,0x83,0x84,0x85,0x86,0x87,0x88, 0x89,0x8A,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0xA2,0xA3,0xA4,0xA5,0xA6, 0xA7,0xA8,0xA9,0xAA,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xC2,0xC3,0xC4, 0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xE1, 0xE2,0xE3,0xE4,0xE5,0xE6,0xE7,0xE8,0xE9,0xEA,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7, 0xF8,0xF9,0xFA, }; static uint8_t const std_dht11[179] = { 0x11,0x00,0x02,0x01,0x02,0x04,0x04,0x03,0x04,0x07,0x05,0x04,0x04,0x00,0x01,0x02, 0x77,0x00,0x01,0x02,0x03,0x11,0x04,0x05,0x21,0x31,0x06,0x12,0x41,0x51,0x07,0x61, 0x71,0x13,0x22,0x32,0x81,0x08,0x14,0x42,0x91,0xA1,0xB1,0xC1,0x09,0x23,0x33,0x52, 0xF0,0x15,0x62,0x72,0xD1,0x0A,0x16,0x24,0x34,0xE1,0x25,0xF1,0x17,0x18,0x19,0x1A, 0x26,0x27,0x28,0x29,0x2A,0x35,0x36,0x37,0x38,0x39,0x3A,0x43,0x44,0x45,0x46,0x47, 0x48,0x49,0x4A,0x53,0x54,0x55,0x56,0x57,0x58,0x59,0x5A,0x63,0x64,0x65,0x66,0x67, 0x68,0x69,0x6A,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7A,0x82,0x83,0x84,0x85,0x86, 0x87,0x88,0x89,0x8A,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0xA2,0xA3,0xA4, 0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xC2, 0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9, 0xDA,0xE2,0xE3,0xE4,0xE5,0xE6,0xE7,0xE8,0xE9,0xEA,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7, 0xF8,0xF9,0xFA, }; /* Helper for returning the current DHT table */ #define SDHT (s->sdht[s->acpart ? 1 : 0][s->component ? 1 : 0]) #define DDHT (s->ddht[s->acpart ? 1 : 0][s->component ? 1 : 0]) /* Helpers for looking up the current DQT value */ #define SDQT (s->sdqt[s->component ? 1 : 0][1 + s->acpart]) #define DDQT (s->ddqt[s->component ? 1 : 0][1 + s->acpart]) /* Helpers for converting between DQT tables */ #define AADJ(i) (SDQT == DDQT ? (i) : irdiv(i, DDQT)) #define UADJ(i) (SDQT == DDQT ? (i) : (i * SDQT)) #define BADJ(i) (SDQT == DDQT ? (i) : irdiv(i * SDQT, DDQT)) /* Integer-only division with rounding */ static int irdiv(int i, int div) { i = i * 2 / div; if(i & 1) i += (i > 0 ? 1 : -1); return(i / 2); } /* static char *strbits(uint32_t value, uint8_t bits) { static char s[33]; char *ss = s; while(bits--) *(ss++) = value & 1 << bits ? '1' : '0'; *ss = '\0'; return(s); } */ static void load_standard_dqt(uint8_t *dst, const uint8_t *table, uint8_t quality) { int i; uint16_t scale_factor; uint32_t temp; /* Copy the table ID */ *dst++ = *table++; /* Load the scaling factor */ if(quality > 7) quality = 7; scale_factor = dqt_scales[quality]; /* Copy the remaining 64 coefficients, while applying the scaling factor */ for(i = 0; i < 64; i++) { temp = *table++; temp = (temp * scale_factor + 50) / 100; /* limit the values to the valid range */ if(temp == 0) temp = 1; if(temp > 255) temp = 255; *dst++ = temp; } } static void *sload_standard_dqt(ssdv_t *s, const uint8_t *table, uint8_t quality) { uint8_t *r; /* DQT is 65 bytes long, ensure there is space */ if(s->stbl_len + 65 > TBL_LEN + HBUFF_LEN) return(NULL); r = &s->stbls[s->stbl_len]; load_standard_dqt(r, table, quality); s->stbl_len += 65; return(r); } static void *dload_standard_dqt(ssdv_t *s, const uint8_t *table, uint8_t quality) { uint8_t *r; /* DQT is 65 bytes long, ensure there is space */ if(s->dtbl_len + 65 > TBL_LEN + HBUFF_LEN) return(NULL); r = &s->dtbls[s->dtbl_len]; load_standard_dqt(r, table, quality); s->dtbl_len += 65; return(r); } static void *stblcpy(ssdv_t *s, const void *src, size_t n) { void *r; if(s->stbl_len + n > TBL_LEN + HBUFF_LEN) return(NULL); r = memcpy(&s->stbls[s->stbl_len], src, n); s->stbl_len += n; return(r); } static void *dtblcpy(ssdv_t *s, const void *src, size_t n) { void *r; if(s->dtbl_len + n > TBL_LEN) return(NULL); r = memcpy(&s->dtbls[s->dtbl_len], src, n); s->dtbl_len += n; return(r); } static uint32_t crc32(void *data, size_t length) { uint32_t crc, x; uint8_t i, *d; for(d = data, crc = 0xFFFFFFFF; length; length--) { x = (crc ^ *(d++)) & 0xFF; for(i = 8; i > 0; i--) { if(x & 1) x = (x >> 1) ^ 0xEDB88320; else x >>= 1; } crc = (crc >> 8) ^ x; } return(crc ^ 0xFFFFFFFF); } static uint32_t encode_callsign(char *callsign) { uint32_t x; char *c; /* Point c at the end of the callsign, maximum of 6 characters */ for(x = 0, c = callsign; x < SSDV_MAX_CALLSIGN && *c; x++, c++); /* Encode it backwards */ x = 0; for(c--; c >= callsign; c--) { x *= 40; if(*c >= 'A' && *c <= 'Z') x += *c - 'A' + 14; else if(*c >= 'a' && *c <= 'z') x += *c - 'a' + 14; else if(*c >= '0' && *c <= '9') x += *c - '0' + 1; } return(x); } static char *decode_callsign(char *callsign, uint32_t code) { char *c, s; *callsign = '\0'; /* Is callsign valid? */ if(code > 0xF423FFFF) return(callsign); for(c = callsign; code; c++) { s = code % 40; if(s == 0) *c = '-'; else if(s < 11) *c = '0' + s - 1; else if(s < 14) *c = '-'; else *c = 'A' + s - 14; code /= 40; } *c = '\0'; return(callsign); } static inline char jpeg_dht_lookup(ssdv_t *s, uint8_t *symbol, uint8_t *width) { uint16_t code = 0; uint8_t cw, n; uint8_t *dht, *ss; /* Select the appropriate huffman table */ dht = SDHT; ss = &dht[17]; for(cw = 1; cw <= 16; cw++) { /* Got enough bits? */ if(cw > s->worklen) return(SSDV_FEED_ME); /* Compare against each code 'cw' bits wide */ for(n = dht[cw]; n > 0; n--) { if(s->workbits >> (s->worklen - cw) == code) { /* Found a match */ *symbol = *ss; *width = cw; return(SSDV_OK); } ss++; code++; } code <<= 1; } /* No match found - error */ return(SSDV_ERROR); } static inline char jpeg_dht_lookup_symbol(ssdv_t *s, uint8_t symbol, uint16_t *bits, uint8_t *width) { uint16_t code = 0; uint8_t cw, n; uint8_t *dht, *ss; dht = DDHT; ss = &dht[17]; for(cw = 1; cw <= 16; cw++) { for(n = dht[cw]; n > 0; n--) { if(*ss == symbol) { /* Found a match */ *bits = code; *width = cw; return(SSDV_OK); } ss++; code++; } code <<= 1; } /* No match found - error */ return(SSDV_ERROR); } static inline int jpeg_int(int bits, int width) { int b = (1 << width) - 1; if(bits <= b >> 1) bits = -(bits ^ b); return(bits); } static inline void jpeg_encode_int(int value, int *bits, uint8_t *width) { *bits = value; /* Calculate the number of bits */ if(value < 0) value = -value; for(*width = 0; value; value >>= 1) (*width)++; /* Fix negative values */ if(*bits < 0) *bits = -*bits ^ ((1 << *width) - 1); } /*****************************************************************************/ static char ssdv_outbits(ssdv_t *s, uint16_t bits, uint8_t length) { uint8_t b; if(length) { s->outbits <<= length; s->outbits |= bits & ((1 << length) - 1); s->outlen += length; } while(s->outlen >= 8 && s->out_len > 0) { b = s->outbits >> (s->outlen - 8); /* Put the byte into the output buffer */ *(s->outp++) = b; s->outlen -= 8; s->out_len--; /* Insert stuffing byte if needed */ if(s->out_stuff && b == 0xFF) { s->outbits &= (1 << s->outlen) - 1; s->outlen += 8; } } return(s->out_len ? SSDV_OK : SSDV_BUFFER_FULL); } static char ssdv_outbits_sync(ssdv_t *s) { uint8_t b = s->outlen % 8; if(b) return(ssdv_outbits(s, 0xFF, 8 - b)); return(SSDV_OK); } static char ssdv_out_jpeg_int(ssdv_t *s, uint8_t rle, int value) { uint16_t huffbits = 0; int intbits; uint8_t hufflen = 0, intlen; int r; jpeg_encode_int(value, &intbits, &intlen); r = jpeg_dht_lookup_symbol(s, (rle << 4) | (intlen & 0x0F), &huffbits, &hufflen); if(r != SSDV_OK) fprintf(stderr, "jpeg_dht_lookup_symbol: %i (%i:%i)\n", r, value, rle); ssdv_outbits(s, huffbits, hufflen); if(intlen) ssdv_outbits(s, intbits, intlen); return(SSDV_OK); } static char ssdv_process(ssdv_t *s) { if(s->state == S_HUFF) { uint8_t symbol, width; int r; if(s->mcupart == 0 && s->acpart == 0 && s->next_reset_mcu > s->reset_mcu) { s->reset_mcu = s->next_reset_mcu; } /* Lookup the code, return if error or not enough bits yet */ if((r = jpeg_dht_lookup(s, &symbol, &width)) != SSDV_OK) { return(r); } if(s->acpart == 0) /* DC */ { if(symbol == 0x00) { /* No change in DC from last block */ if(s->reset_mcu == s->mcu_id && (s->mcupart == 0 || s->mcupart >= s->ycparts)) { if(s->mode == S_ENCODING) { ssdv_out_jpeg_int(s, 0, s->adc[s->component]); } else { ssdv_out_jpeg_int(s, 0, 0 - s->dc[s->component]); s->dc[s->component] = 0; } } else ssdv_out_jpeg_int(s, 0, 0); /* skip to the next AC part immediately */ s->acpart++; } else { /* DC value follows, 'symbol' bits wide */ s->state = S_INT; s->needbits = symbol; } } else /* AC */ { s->acrle = 0; if(symbol == 0x00) { /* EOB -- all remaining AC parts are zero */ ssdv_out_jpeg_int(s, 0, 0); s->acpart = 64; } else if(symbol == 0xF0) { /* The next 16 AC parts are zero */ ssdv_out_jpeg_int(s, 15, 0); s->acpart += 16; } else { /* Next bits are an integer value */ s->state = S_INT; s->acrle = symbol >> 4; s->acpart += s->acrle; s->needbits = symbol & 0x0F; } } /* Clear processed bits */ s->worklen -= width; s->workbits &= (1 << s->worklen) - 1; } else if(s->state == S_INT) { int i; /* Not enough bits yet? */ if(s->worklen < s->needbits) return(SSDV_FEED_ME); /* Decode the integer */ i = jpeg_int(s->workbits >> (s->worklen - s->needbits), s->needbits); if(s->acpart == 0) /* DC */ { if(s->reset_mcu == s->mcu_id && (s->mcupart == 0 || s->mcupart >= s->ycparts)) { if(s->mode == S_ENCODING) { /* Output absolute DC value */ s->dc[s->component] += UADJ(i); s->adc[s->component] = AADJ(s->dc[s->component]); ssdv_out_jpeg_int(s, 0, s->adc[s->component]); } else { /* Output relative DC value */ ssdv_out_jpeg_int(s, 0, i - s->dc[s->component]); s->dc[s->component] = i; } } else { if(s->mode == S_DECODING) { s->dc[s->component] += UADJ(i); ssdv_out_jpeg_int(s, 0, i); } else { /* Output relative DC value */ s->dc[s->component] += UADJ(i); /* Calculate closest adjusted DC value */ i = AADJ(s->dc[s->component]); ssdv_out_jpeg_int(s, 0, i - s->adc[s->component]); s->adc[s->component] = i; } } } else /* AC */ { if((i = BADJ(i))) { s->accrle += s->acrle; while(s->accrle >= 16) { ssdv_out_jpeg_int(s, 15, 0); s->accrle -= 16; } ssdv_out_jpeg_int(s, s->accrle, i); s->accrle = 0; } else { /* AC value got reduced to 0 in the DQT conversion */ if(s->acpart >= 63) { ssdv_out_jpeg_int(s, 0, 0); s->accrle = 0; } else s->accrle += s->acrle + 1; } } /* Next AC part to expect */ s->acpart++; /* Next bits are a huffman code */ s->state = S_HUFF; /* Clear processed bits */ s->worklen -= s->needbits; s->workbits &= (1 << s->worklen) - 1; } if(s->acpart >= 64) { s->mcupart++; if(s->greyscale && s->mcupart == s->ycparts) { /* For greyscale input images, pad the 2x1 MCUs with empty colour blocks */ for(; s->mcupart < s->ycparts + 2; s->mcupart++) { s->component = s->mcupart - s->ycparts + 1; s->acpart = 0; ssdv_out_jpeg_int(s, 0, 0); /* DC */ s->acpart = 1; ssdv_out_jpeg_int(s, 0, 0); /* AC */ } } /* Reached the end of this MCU */ if(s->mcupart == s->ycparts + 2) { s->mcupart = 0; s->mcu_id++; /* Test for the end of image */ if(s->mcu_id >= s->mcu_count) { /* Flush any remaining bits */ ssdv_outbits_sync(s); return(SSDV_EOI); } /* Set the packet MCU marker - encoder only */ if(s->mode == S_ENCODING && s->packet_mcu_id == 0xFFFF) { /* The first MCU of each packet should be byte aligned */ ssdv_outbits_sync(s); s->next_reset_mcu = s->mcu_id; s->packet_mcu_id = s->mcu_id; s->packet_mcu_offset = s->pkt_size_payload - s->out_len + ((s->outlen + 7) / 8); } /* Test for a reset marker */ if(s->dri > 0 && s->mcu_id > 0 && s->mcu_id % s->dri == 0) { s->state = S_MARKER; return(SSDV_FEED_ME); } } if(s->mcupart < s->ycparts) s->component = 0; else s->component = s->mcupart - s->ycparts + 1; s->acpart = 0; s->accrle = 0; } if(s->out_len == 0) return(SSDV_BUFFER_FULL); return(SSDV_OK); } static void ssdv_set_packet_conf(ssdv_t *s) { /* Configure the payload size and CRC position */ switch(s->type) { case SSDV_TYPE_NORMAL: s->pkt_size_payload = SSDV_PKT_SIZE - SSDV_PKT_SIZE_HEADER - SSDV_PKT_SIZE_CRC - SSDV_PKT_SIZE_RSCODES; s->pkt_size_crcdata = SSDV_PKT_SIZE_HEADER + s->pkt_size_payload - 1; break; case SSDV_TYPE_NOFEC: s->pkt_size_payload = SSDV_PKT_SIZE - SSDV_PKT_SIZE_HEADER - SSDV_PKT_SIZE_CRC; s->pkt_size_crcdata = SSDV_PKT_SIZE_HEADER + s->pkt_size_payload - 1; break; } } /*****************************************************************************/ static void ssdv_memset_prng(uint8_t *s, size_t n) { /* A very simple PRNG for noise whitening */ uint8_t l = 0x00; for(; n > 0; n--) *(s++) = (l = l * 245 + 45); } static char ssdv_have_marker(ssdv_t *s) { switch(s->marker) { case J_SOF0: case J_SOS: case J_DRI: case J_DHT: case J_DQT: /* Copy the data before processing */ if(s->marker_len > TBL_LEN + HBUFF_LEN - s->stbl_len) { /* Not enough memory ... shouldn't happen! */ return(SSDV_ERROR); } s->marker_data = &s->stbls[s->stbl_len]; s->marker_data_len = 0; s->state = S_MARKER_DATA; break; case J_SOF2: /* Don't do progressive images! */ fprintf(stderr, "Error: Progressive images not supported\n"); return(SSDV_ERROR); case J_EOI: s->state = S_EOI; break; case J_RST0: case J_RST1: case J_RST2: case J_RST3: case J_RST4: case J_RST5: case J_RST6: case J_RST7: s->dc[0] = s->dc[1] = s->dc[2] = 0; s->mcupart = s->acpart = s->component = 0; s->acrle = s->accrle = 0; s->workbits = s->worklen = 0; s->state = S_HUFF; break; default: /* Ignore other marks, skipping any associated data */ s->in_skip = s->marker_len; s->state = S_MARKER; break; } return(SSDV_OK); } static char ssdv_have_marker_data(ssdv_t *s) { uint8_t *d = s->marker_data; size_t l = s->marker_len; int i; switch(s->marker) { case J_SOF0: s->width = (d[3] << 8) | d[4]; s->height = (d[1] << 8) | d[2]; /* Display information about the image... */ fprintf(stderr, "Precision: %i\n", d[0]); fprintf(stderr, "Resolution: %ix%i\n", s->width, s->height); fprintf(stderr, "Components: %i\n", d[5]); /* The image must have a precision of 8 */ if(d[0] != 8) { fprintf(stderr, "Error: The image must have a precision of 8\n"); return(SSDV_ERROR); } /* The image must have 1 or 3 components (Y'Cb'Cr) */ if(d[5] != 1 && d[5] != 3) { fprintf(stderr, "Error: The image must have 1 or 3 components\n"); return(SSDV_ERROR); } /* Maximum image is 4080x4080 */ if(s->width > 4080 || s->height > 4080) { fprintf(stderr, "Error: The image is too big. Maximum resolution is 4080x4080\n"); return(SSDV_ERROR); } /* The image dimensions must be a multiple of 16 */ if((s->width & 0x0F) || (s->height & 0x0F)) { fprintf(stderr, "Error: The image dimensions must be a multiple of 16\n"); return(SSDV_ERROR); } /* TODO: Read in the quantisation table ID for each component */ // 01 22 00 02 11 01 03 11 01 for(i = 0; i < d[5]; i++) { uint8_t *dq = &d[i * 3 + 6]; if(dq[0] != i + 1) { fprintf(stderr, "Error: Components are not in order in the SOF0 header\n"); return(SSDV_ERROR); } fprintf(stderr, "DQT table for component %i: %02X, Sampling factor: %ix%i\n", dq[0], dq[2], dq[1] & 0x0F, dq[1] >> 4); /* The first (Y) component must have a factor of 2x2,2x1,1x2 or 1x1 */ if(dq[0] == 1) { switch(dq[1]) { case 0x22: s->mcu_mode = 0; s->ycparts = 4; break; case 0x12: s->mcu_mode = 1; s->ycparts = 2; break; case 0x21: s->mcu_mode = 2; s->ycparts = 2; break; case 0x11: s->mcu_mode = 3; s->ycparts = 1; break; default: fprintf(stderr, "Error: Component 1 sampling factor is not supported\n"); return(SSDV_ERROR); } } else if(dq[0] != 1 && dq[1] != 0x11) { fprintf(stderr, "Error: Component %i sampling factor must be 1x1\n", dq[0]); return(SSDV_ERROR); } } if(d[5] == 1) { /* Greyscale images are converted to 2x1 colour images */ s->greyscale = 1; s->mcu_mode = 2; s->ycparts = 2; } /* Calculate number of MCU blocks in this image */ switch(s->mcu_mode) { case 0: l = (s->width >> 4) * (s->height >> 4); break; case 1: l = (s->width >> 4) * (s->height >> 3); break; case 2: l = (s->width >> 3) * (s->height >> 4); break; case 3: l = (s->width >> 3) * (s->height >> 3); break; } fprintf(stderr, "MCU blocks: %i\n", (int) l); if(l > 0xFFFF) { fprintf(stderr, "Error: Maximum number of MCU blocks is 65535\n"); return(SSDV_ERROR); } s->mcu_count = l; break; case J_SOS: fprintf(stderr, "Components: %i\n", d[0]); /* The image must have 1 or 3 components (Y'Cb'Cr) */ if(d[0] != 1 && d[0] != 3) { fprintf(stderr, "Error: The image must have 1 or 3 components\n"); return(SSDV_ERROR); } for(i = 0; i < d[0]; i++) { uint8_t *dh = &d[i * 2 + 1]; if(dh[0] != i + 1) { fprintf(stderr, "Error: Components are not in order in the SOF0 header\n"); return(SSDV_ERROR); } fprintf(stderr, "Component %i DHT: %02X\n", dh[0], dh[1]); } /* Do I need to look at the last three bytes of the SOS data? */ /* 00 3F 00 */ /* Verify all of the DQT and DHT tables where loaded */ if(!s->sdqt[0] || (d[0] > 1 && !s->sdqt[1])) { fprintf(stderr, "Error: The image is missing one or more DQT tables\n"); return(SSDV_ERROR); } if(!s->sdht[0][0] || (d[0] > 1 && !s->sdht[0][1]) || !s->sdht[1][0] || (d[0] > 1 && !s->sdht[1][1])) { fprintf(stderr, "Error: The image is missing one or more DHT tables\n"); return(SSDV_ERROR); } /* The SOS data is followed by the image data */ s->state = S_HUFF; return(SSDV_OK); case J_DHT: s->stbl_len += l; while(l > 0) { int i, j; switch(d[0]) { case 0x00: s->sdht[0][0] = d; break; case 0x01: s->sdht[0][1] = d; break; case 0x10: s->sdht[1][0] = d; break; case 0x11: s->sdht[1][1] = d; break; } /* Skip to the next DHT table */ for(j = 17, i = 1; i <= 16; i++) j += d[i]; l -= j; d += j; } break; case J_DQT: s->stbl_len += l; while(l > 0) { switch(d[0]) { case 0x00: s->sdqt[0] = d; break; case 0x01: s->sdqt[1] = d; break; } /* Skip to the next one, if present */ l -= 65; d += 65; } break; case J_DRI: s->dri = (d[0] << 8) + d[1]; fprintf(stderr, "Reset interval: %i blocks\n", s->dri); break; } s->state = S_MARKER; return(SSDV_OK); } char ssdv_enc_init(ssdv_t *s, uint8_t type, char *callsign, uint8_t image_id, int8_t quality) { /* Limit the quality level */ if(quality < 0) quality = 0; if(quality > 7) quality = 7; memset(s, 0, sizeof(ssdv_t)); s->image_id = image_id; s->callsign = encode_callsign(callsign); s->mode = S_ENCODING; s->type = type; s->quality = quality; ssdv_set_packet_conf(s); /* Prepare the output JPEG tables */ s->ddqt[0] = dload_standard_dqt(s, std_dqt0, s->quality); s->ddqt[1] = dload_standard_dqt(s, std_dqt1, s->quality); s->ddht[0][0] = dtblcpy(s, std_dht00, sizeof(std_dht00)); s->ddht[0][1] = dtblcpy(s, std_dht01, sizeof(std_dht01)); s->ddht[1][0] = dtblcpy(s, std_dht10, sizeof(std_dht10)); s->ddht[1][1] = dtblcpy(s, std_dht11, sizeof(std_dht11)); return(SSDV_OK); } char ssdv_enc_set_buffer(ssdv_t *s, uint8_t *buffer) { s->out = buffer; s->outp = buffer + SSDV_PKT_SIZE_HEADER; s->out_len = s->pkt_size_payload; /* Zero the payload memory */ memset(s->out, 0, SSDV_PKT_SIZE); /* Flush the output bits */ ssdv_outbits(s, 0, 0); return(SSDV_OK); } char ssdv_enc_get_packet(ssdv_t *s) { int r; uint8_t b; /* Have we reached the end of the image? */ if(s->state == S_EOI) return(SSDV_EOI); /* If the output buffer is empty, re-initialise */ if(s->out_len == 0) ssdv_enc_set_buffer(s, s->out); while(s->in_len) { b = *(s->inp++); s->in_len--; /* Skip bytes if necessary */ if(s->in_skip) { s->in_skip--; continue; } switch(s->state) { case S_MARKER: s->marker = (s->marker << 8) | b; if(s->marker == J_TEM || (s->marker >= J_RST0 && s->marker <= J_EOI)) { /* Marker without data */ s->marker_len = 0; r = ssdv_have_marker(s); if(r != SSDV_OK) return(r); } else if(s->marker >= J_SOF0 && s->marker <= J_COM) { /* All other markers are followed by data */ s->marker_len = 0; s->state = S_MARKER_LEN; s->needbits = 16; } break; case S_MARKER_LEN: s->marker_len = (s->marker_len << 8) | b; if((s->needbits -= 8) == 0) { s->marker_len -= 2; r = ssdv_have_marker(s); if(r != SSDV_OK) return(r); } break; case S_MARKER_DATA: s->marker_data[s->marker_data_len++] = b; if(s->marker_data_len == s->marker_len) { r = ssdv_have_marker_data(s); if(r != SSDV_OK) return(r); } break; case S_HUFF: case S_INT: /* Is the next byte a stuffing byte? Skip it */ /* TODO: Test the next byte is actually 0x00 */ if(b == 0xFF) s->in_skip++; /* Add the new byte to the work area */ s->workbits = (s->workbits << 8) | b; s->worklen += 8; /* Process the new data until more needed, or an error occurs */ while((r = ssdv_process(s)) == SSDV_OK); if(r == SSDV_BUFFER_FULL || r == SSDV_EOI) { uint16_t mcu_id = s->packet_mcu_id; uint8_t mcu_offset = s->packet_mcu_offset; uint32_t x; uint8_t i; if(mcu_offset != 0xFF && mcu_offset >= s->pkt_size_payload) { /* The first MCU begins in the next packet, not this one */ mcu_id = 0xFFFF; mcu_offset = 0xFF; s->packet_mcu_offset -= s->pkt_size_payload; } else { /* Clear the MCU data for the next packet */ s->packet_mcu_id = 0xFFFF; s->packet_mcu_offset = 0xFF; } /* A packet is ready, create the headers */ s->out[0] = 0x55; /* Sync */ s->out[1] = 0x66 + s->type; /* Type */ s->out[2] = s->callsign >> 24; s->out[3] = s->callsign >> 16; s->out[4] = s->callsign >> 8; s->out[5] = s->callsign; s->out[6] = s->image_id; /* Image ID */ s->out[7] = s->packet_id >> 8; /* Packet ID MSB */ s->out[8] = s->packet_id & 0xFF; /* Packet ID LSB */ s->out[9] = s->width >> 4; /* Width / 16 */ s->out[10] = s->height >> 4; /* Height / 16 */ s->out[11] = 0x00; s->out[11] |= ((s->quality - 4) & 7) << 3; /* Quality level */ s->out[11] |= (r == SSDV_EOI ? 1 : 0) << 2; /* EOI flag (1 bit) */ s->out[11] |= s->mcu_mode & 0x03; /* MCU mode (2 bits) */ s->out[12] = mcu_offset; /* Next MCU offset */ s->out[13] = mcu_id >> 8; /* MCU ID MSB */ s->out[14] = mcu_id & 0xFF; /* MCU ID LSB */ /* Fill any remaining bytes with noise */ if(s->out_len > 0) ssdv_memset_prng(s->outp, s->out_len); /* Calculate the CRC codes */ x = crc32(&s->out[1], s->pkt_size_crcdata); i = 1 + s->pkt_size_crcdata; s->out[i++] = (x >> 24) & 0xFF; s->out[i++] = (x >> 16) & 0xFF; s->out[i++] = (x >> 8) & 0xFF; s->out[i++] = x & 0xFF; /* Generate the RS codes */ if(s->type == SSDV_TYPE_NORMAL) encode_rs_8(&s->out[1], &s->out[i], 0); s->packet_id++; /* Have we reached the end of the image data? */ if(r == SSDV_EOI) s->state = S_EOI; return(SSDV_OK); } else if(r != SSDV_FEED_ME) { /* An error occured */ fprintf(stderr, "ssdv_process() failed: %i\n", r); return(SSDV_ERROR); } break; case S_EOI: /* Shouldn't reach this point */ break; } } /* Need more data */ return(SSDV_FEED_ME); } char ssdv_enc_feed(ssdv_t *s, uint8_t *buffer, size_t length) { s->inp = buffer; s->in_len = length; return(SSDV_OK); } /*****************************************************************************/ static void ssdv_write_marker(ssdv_t *s, uint16_t id, uint16_t length, const uint8_t *data) { ssdv_outbits(s, id, 16); if(length > 0) { ssdv_outbits(s, length + 2, 16); while(length--) ssdv_outbits(s, *(data++), 8); } } static void ssdv_out_headers(ssdv_t *s) { uint8_t *b = &s->stbls[s->stbl_len]; ssdv_write_marker(s, J_SOI, 0, 0); ssdv_write_marker(s, J_APP0, 14, app0); ssdv_write_marker(s, J_DQT, 65, s->ddqt[0]); /* DQT Luminance */ ssdv_write_marker(s, J_DQT, 65, s->ddqt[1]); /* DQT Chrominance */ /* Build SOF0 header */ b[0] = 8; /* Precision */ b[1] = s->height >> 8; b[2] = s->height & 0xFF; b[3] = s->width >> 8; b[4] = s->width & 0xFF; b[5] = 3; /* Components (Y'Cb'Cr) */ b[6] = 1; /* Y */ switch(s->mcu_mode) { case 0: b[7] = 0x22; break; case 1: b[7] = 0x12; break; case 2: b[7] = 0x21; break; case 3: b[7] = 0x11; break; } b[8] = 0x00; b[9] = 2; /* Cb */ b[10] = 0x11; b[11] = 0x01; b[12] = 3; /* Cr */ b[13] = 0x11; b[14] = 0x01; ssdv_write_marker(s, J_SOF0, 15, b); /* SOF0 (Baseline DCT) */ ssdv_write_marker(s, J_DHT, 29, std_dht00); /* DHT (DC Luminance) */ ssdv_write_marker(s, J_DHT, 179, std_dht10); /* DHT (AC Luminance) */ ssdv_write_marker(s, J_DHT, 29, std_dht01); /* DHT (DC Chrominance */ ssdv_write_marker(s, J_DHT, 179, std_dht11); /* DHT (AC Chrominance */ ssdv_write_marker(s, J_SOS, 10, sos); } static void ssdv_fill_gap(ssdv_t *s, uint16_t next_mcu) { if(s->mcupart > 0 || s->acpart > 0) { /* Cleanly end the current MCU part */ if(s->acpart > 0) { ssdv_out_jpeg_int(s, 0, 0); s->mcupart++; } /* End the current MCU block */ for(; s->mcupart < s->ycparts + 2; s->mcupart++) { if(s->mcupart < s->ycparts) s->component = 0; else s->component = s->mcupart - s->ycparts + 1; s->acpart = 0; ssdv_out_jpeg_int(s, 0, 0); /* DC */ s->acpart = 1; ssdv_out_jpeg_int(s, 0, 0); /* AC */ } s->mcu_id++; } /* Pad out missing MCUs */ for(; s->mcu_id < next_mcu; s->mcu_id++) { /* End the current MCU block */ for(s->mcupart = 0; s->mcupart < s->ycparts + 2; s->mcupart++) { if(s->mcupart < s->ycparts) s->component = 0; else s->component = s->mcupart - s->ycparts + 1; s->acpart = 0; ssdv_out_jpeg_int(s, 0, 0); /* DC */ s->acpart = 1; ssdv_out_jpeg_int(s, 0, 0); /* AC */ } } } char ssdv_dec_init(ssdv_t *s) { memset(s, 0, sizeof(ssdv_t)); /* The packet data should contain only scan data, no headers */ s->state = S_HUFF; s->mode = S_DECODING; /* Prepare the source JPEG tables */ s->sdht[0][0] = stblcpy(s, std_dht00, sizeof(std_dht00)); s->sdht[0][1] = stblcpy(s, std_dht01, sizeof(std_dht01)); s->sdht[1][0] = stblcpy(s, std_dht10, sizeof(std_dht10)); s->sdht[1][1] = stblcpy(s, std_dht11, sizeof(std_dht11)); /* Prepare the output JPEG tables */ s->ddht[0][0] = dtblcpy(s, std_dht00, sizeof(std_dht00)); s->ddht[0][1] = dtblcpy(s, std_dht01, sizeof(std_dht01)); s->ddht[1][0] = dtblcpy(s, std_dht10, sizeof(std_dht10)); s->ddht[1][1] = dtblcpy(s, std_dht11, sizeof(std_dht11)); return(SSDV_OK); } char ssdv_dec_set_buffer(ssdv_t *s, uint8_t *buffer, size_t length) { size_t c = s->outp - s->out; s->outp = buffer + c; s->out = buffer; s->out_len = length - c; /* Flush the output bits */ ssdv_outbits(s, 0, 0); return(SSDV_OK); } char ssdv_dec_feed(ssdv_t *s, uint8_t *packet) { int i = 0, r; uint8_t b; uint16_t packet_id; /* Read the packet header */ packet_id = (packet[7] << 8) | packet[8]; s->packet_mcu_offset = packet[12]; s->packet_mcu_id = (packet[13] << 8) | packet[14]; if(s->packet_mcu_id != 0xFFFF) { /* Set the next reset MCU ID */ s->next_reset_mcu = s->packet_mcu_id; } /* If this is the first packet, write the JPEG headers */ if(s->packet_id == 0) { const char *factor; char callsign[SSDV_MAX_CALLSIGN + 1]; /* Read the fixed headers from the packet */ s->type = packet[1] - 0x66; s->callsign = (packet[2] << 24) | (packet[3] << 16) | (packet[4] << 8) | packet[5]; s->image_id = packet[6]; s->width = packet[9] << 4; s->height = packet[10] << 4; s->mcu_count = packet[9] * packet[10]; s->quality = ((packet[11] >> 3) & 7) ^ 4; s->mcu_mode = packet[11] & 0x03; /* Configure the payload size and CRC position */ ssdv_set_packet_conf(s); /* Generate the DQT tables */ s->sdqt[0] = sload_standard_dqt(s, std_dqt0, s->quality); s->sdqt[1] = sload_standard_dqt(s, std_dqt1, s->quality); s->ddqt[0] = dload_standard_dqt(s, std_dqt0, s->quality); s->ddqt[1] = dload_standard_dqt(s, std_dqt1, s->quality); switch(s->mcu_mode & 3) { case 0: factor = "2x2"; s->ycparts = 4; break; case 1: factor = "1x2"; s->ycparts = 2; s->mcu_count *= 2; break; case 2: factor = "2x1"; s->ycparts = 2; s->mcu_count *= 2; break; case 3: factor = "1x1"; s->ycparts = 1; s->mcu_count *= 4; break; } /* Display information about the image */ fprintf(stderr, "Callsign: %s\n", decode_callsign(callsign, s->callsign)); fprintf(stderr, "Image ID: %02X\n", s->image_id); fprintf(stderr, "Resolution: %ix%i\n", s->width, s->height); fprintf(stderr, "MCU blocks: %i\n", s->mcu_count); fprintf(stderr, "Sampling factor: %s\n", factor); fprintf(stderr, "Quality level: %d\n", s->quality); /* Output JPEG headers and enable byte stuffing */ ssdv_out_headers(s); s->out_stuff = 1; } /* Is this not the packet we expected? */ if(packet_id != s->packet_id) { /* One or more packets have been lost! */ fprintf(stderr, "Gap detected between packets %i and %i\n", s->packet_id - 1, packet_id); /* If this packet has no new MCU, ignore */ if(s->packet_mcu_id == 0xFFFF) return(SSDV_FEED_ME); /* Fill the gap left by the missing packet */ ssdv_fill_gap(s, s->packet_mcu_id); /* Skip the bytes of the lost MCU */ i = s->packet_mcu_offset; /* Reset the JPEG decoder state */ s->state = S_HUFF; s->component = 0; s->mcupart = 0; s->acpart = 0; s->accrle = 0; s->packet_id = packet_id; } /* Feed the JPEG data into the processor */ for(; i < s->pkt_size_payload; i++) { if(i == s->packet_mcu_offset) { /* The first MCU in a packet is byte aligned, * any old bits should be dropped. */ s->workbits = s->worklen = 0; } b = packet[SSDV_PKT_SIZE_HEADER + i]; /* Add the new byte to the work area */ s->workbits = (s->workbits << 8) | b; s->worklen += 8; /* Process the new data until more needed, or an error occurs */ while((r = ssdv_process(s)) == SSDV_OK); if(r == SSDV_BUFFER_FULL) { /* Realloc memory */ } else if(r == SSDV_EOI) { /* All done! */ return(SSDV_OK); } else if(r != SSDV_FEED_ME) { /* An error occured */ fprintf(stderr, "ssdv_process() failed: %i\n", r); return(SSDV_ERROR); } } /* The next packet to expect... */ s->packet_id++; return(SSDV_FEED_ME); } char ssdv_dec_get_jpeg(ssdv_t *s, uint8_t **jpeg, size_t *length) { /* Is the image complete? */ if(s->mcu_id < s->mcu_count) ssdv_fill_gap(s, s->mcu_count); /* Sync, and final EOI header and return */ ssdv_outbits_sync(s); s->out_stuff = 0; ssdv_write_marker(s, J_EOI, 0, 0); *jpeg = s->out; *length = (size_t) (s->outp - s->out); return(SSDV_OK); } char ssdv_dec_is_packet(uint8_t *packet, int *errors) { uint8_t pkt[SSDV_PKT_SIZE]; uint8_t type; uint16_t pkt_size_payload; uint16_t pkt_size_crcdata; ssdv_packet_info_t p; uint32_t x; int i; /* Testing is destructive, work on a copy */ memcpy(pkt, packet, SSDV_PKT_SIZE); pkt[0] = 0x55; type = SSDV_TYPE_INVALID; if(pkt[1] == 0x66 + SSDV_TYPE_NOFEC) { /* Test for a valid NOFEC packet */ pkt_size_payload = SSDV_PKT_SIZE - SSDV_PKT_SIZE_HEADER - SSDV_PKT_SIZE_CRC; pkt_size_crcdata = SSDV_PKT_SIZE_HEADER + pkt_size_payload - 1; /* No FEC scan */ if(errors) *errors = 0; /* Test the checksum */ x = crc32(&pkt[1], pkt_size_crcdata); i = 1 + pkt_size_crcdata; if(x == (pkt[i + 3] | (pkt[i + 2] << 8) | (pkt[i + 1] << 16) | (pkt[i] << 24))) { /* Valid, set the type and continue */ type = SSDV_TYPE_NOFEC; } } else if(pkt[1] == 0x66 + SSDV_TYPE_NORMAL) { /* Test for a valid NORMAL packet */ pkt_size_payload = SSDV_PKT_SIZE - SSDV_PKT_SIZE_HEADER - SSDV_PKT_SIZE_CRC - SSDV_PKT_SIZE_RSCODES; pkt_size_crcdata = SSDV_PKT_SIZE_HEADER + pkt_size_payload - 1; /* No FEC scan */ if(errors) *errors = 0; /* Test the checksum */ x = crc32(&pkt[1], pkt_size_crcdata); i = 1 + pkt_size_crcdata; if(x == (pkt[i + 3] | (pkt[i + 2] << 8) | (pkt[i + 1] << 16) | (pkt[i] << 24))) { /* Valid, set the type and continue */ type = SSDV_TYPE_NORMAL; } } if(type == SSDV_TYPE_INVALID) { /* Test for a valid NORMAL packet with correctable errors */ pkt_size_payload = SSDV_PKT_SIZE - SSDV_PKT_SIZE_HEADER - SSDV_PKT_SIZE_CRC - SSDV_PKT_SIZE_RSCODES; pkt_size_crcdata = SSDV_PKT_SIZE_HEADER + pkt_size_payload - 1; /* Run the reed-solomon decoder */ pkt[1] = 0x66 + SSDV_TYPE_NORMAL; i = decode_rs_8(&pkt[1], 0, 0, 0); if(i < 0) return(-1); /* Reed-solomon decoder failed */ if(errors) *errors = i; /* Test the checksum */ x = crc32(&pkt[1], pkt_size_crcdata); i = 1 + pkt_size_crcdata; if(x == (pkt[i + 3] | (pkt[i + 2] << 8) | (pkt[i + 1] << 16) | (pkt[i] << 24))) { /* Valid, set the type and continue */ type = SSDV_TYPE_NORMAL; } } if(type == SSDV_TYPE_INVALID) { /* All attempts to read the packet have failed */ return(-1); } /* Sanity checks */ ssdv_dec_header(&p, pkt); if(p.type != type) return(-1); if(p.width == 0 || p.height == 0) return(-1); if(p.mcu_id != 0xFFFF) { if(p.mcu_id >= p.mcu_count) return(-1); if(p.mcu_offset >= pkt_size_payload) return(-1); } /* Appears to be a valid packet! Copy it back */ memcpy(packet, pkt, SSDV_PKT_SIZE); return(0); } void ssdv_dec_header(ssdv_packet_info_t *info, uint8_t *packet) { info->type = packet[1] - 0x66; info->callsign = (packet[2] << 24) | (packet[3] << 16) | (packet[4] << 8) | packet[5]; decode_callsign(info->callsign_s, info->callsign); info->image_id = packet[6]; info->packet_id = (packet[7] << 8) | packet[8]; info->width = packet[9] << 4; info->height = packet[10] << 4; info->eoi = (packet[11] >> 2) & 1; info->quality = ((packet[11] >> 3) & 7) ^ 4; info->mcu_mode = packet[11] & 0x03; info->mcu_offset = packet[12]; info->mcu_id = (packet[13] << 8) | packet[14]; info->mcu_count = packet[9] * packet[10]; if(info->mcu_mode == 1 || info->mcu_mode == 2) info->mcu_count *= 2; else if(info->mcu_mode == 3) info->mcu_count *= 4; } /*****************************************************************************/