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First attempt at the new 'hardened' packet format. Untested.

master
Philip Heron 2010-09-30 23:28:13 +01:00
rodzic 2a7aeeaedd
commit 8acbec06c1
4 zmienionych plików z 668 dodań i 38 usunięć
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2
Makefile
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@ -1,6 +1,6 @@
PROJECT=hadie
OBJECTS=hadie.o rtty.o gps.o rs8encode.o c328.o
OBJECTS=hadie.o rtty.o gps.o rs8encode.o c328.o ssdv.o
# Serial device used for programming AVR
TTYPORT=/dev/ttyACM0

56
hadie.c
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@ -17,6 +17,7 @@
#include "gps.h"
#include "c328.h"
#include "rs8.h"
#include "ssdv.h"
/* Message buffer */
#define MSG_SIZE (100)
@ -25,38 +26,17 @@ char msg[MSG_SIZE];
#define PREFIX "$$$$"
/* Image TX data */
#define PKT_SIZE (0x100)
#define PKT_SIZE_HEADER (0x0A)
#define PKT_SIZE_RSCODES (0x20)
#define PKT_SIZE_PAYLOAD (PKT_SIZE - PKT_SIZE_HEADER - PKT_SIZE_RSCODES)
uint8_t pkt[PKT_SIZE];
uint8_t image_pkts;
void init_packet(uint8_t *packet, uint8_t imageid, uint8_t pktid, uint8_t pkts, uint16_t width, uint16_t height)
{
packet[0] = 0x55; /* Sync */
packet[1] = 0x66; /* Type */
packet[2] = imageid; /* Image ID */
packet[3] = pktid; /* Packet ID */
packet[4] = pkts; /* Packets */
packet[5] = width >> 4; /* Width MCU */
packet[6] = height >> 4; /* Height MCU */
packet[7] = 0xFF; /* Next MCU offset */
packet[8] = 0x00; /* MCU ID MSB */
packet[9] = 0x00; /* MCU ID LSB */
memset(&packet[PKT_SIZE_HEADER], 0, PKT_SIZE_PAYLOAD);
}
uint8_t pkt[SSDV_PKT_SIZE], img[64];
char tx_image(void)
{
static char setup = 0;
static uint8_t img_id = 0;
static uint8_t pkt_id;
static ssdv_t ssdv;
int r;
if(!setup)
{
uint16_t image_len;
if(c3_open(SR_320x240) != 0)
{
rtx_string_P(PSTR(PREFIX CALLSIGN ":Camera error\n"));
@ -64,35 +44,37 @@ char tx_image(void)
}
setup = -1;
pkt_id = 0;
img_id++;
/* Calculate the number of packets needed for this image */
image_len = c3_filesize();
image_pkts = image_len / PKT_SIZE_PAYLOAD;
image_pkts += (image_len % PKT_SIZE_PAYLOAD > 0 ? 1 : 0);
ssdv_enc_init(&ssdv, img_id++);
ssdv_enc_set_buffer(&ssdv, pkt);
}
/* Initialise the packet */
init_packet(pkt, img_id, pkt_id++, image_pkts, 320, 240);
if(c3_read(&pkt[PKT_SIZE_HEADER], PKT_SIZE_PAYLOAD) == 0)
while((r = ssdv_enc_get_packet(&ssdv)) == SSDV_FEED_ME)
{
rtx_string_P(PSTR(PREFIX CALLSIGN ":Error reading from camera\n"));
size_t r = c3_read(img, 64);
if(r == 0) break;
ssdv_enc_feed(&ssdv, img, r);
}
if(r != SSDV_OK)
{
/* Something went wrong! */
c3_close();
setup = 0;
rtx_string_P(PSTR(PREFIX CALLSIGN ":ssdv_enc_get_packet() failed\n"));
return(setup);
}
if(c3_eof())
{
/* The end of the image has been reached */
c3_close();
setup = 0;
}
encode_rs_8(&pkt[1], &pkt[PKT_SIZE_HEADER + PKT_SIZE_PAYLOAD], 0);
/* Got the packet! Transmit it */
rtx_string_P(PSTR("UUU")); /* U = 0x55 */
rtx_data(pkt, PKT_SIZE);
rtx_data(pkt, SSDV_PKT_SIZE);
return(setup);
}

554
ssdv.c 100644
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@ -0,0 +1,554 @@
/* hadie - High Altitude Balloon flight software */
/*============================================================*/
/* Copyright (C)2010 Philip Heron <phil@sanslogic.co.uk> */
/* */
/* This program is distributed under the terms of the GNU */
/* General Public License, version 2. You may use, modify, */
/* and redistribute it under the terms of this license. A */
/* copy should be included with this source. */
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#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;
/* Huffman tables for output (and for the C328 camera, input also) */
static uint8_t 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 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 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 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,
};
static uint8_t *dht_dc[3] = { dht00, dht01, dht01 };
static uint8_t *dht_ac[3] = { dht10, dht11, dht11 };
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 */
if(s->acpart == 0) dht = dht_dc[s->component];
else dht = dht_ac[s->component];
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(uint8_t *dht, uint8_t symbol, uint16_t *bits, uint8_t *width)
{
uint16_t code = 0;
uint8_t cw, n, *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--;
}
return(s->out_len ? SSDV_OK : SSDV_BUFFER_FULL);
}
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;
uint8_t *dht;
int r;
/* Select the appropriate huffman table */
/* TODO: Do this elsewhere */
if(s->acpart == 0) dht = dht_dc[s->component];
else dht = dht_ac[s->component];
jpeg_encode_int(value, &intbits, &intlen);
r = jpeg_dht_lookup_symbol(dht, (rle << 4) | (intlen & 0x0F), &huffbits, &hufflen);
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 == J_HUFF)
{
uint8_t symbol, width;
int r;
/* 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->mcupart == 0 || s->mcupart == 4 || s->mcupart == 5)
ssdv_out_jpeg_int(s, 0, s->dc[s->component]);
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 = J_INT;
s->needbits = symbol;
}
}
else /* AC */
{
/* Output AC codes directly */
//ssdv_out_huff(s, symbol);
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 15 AC parts are zero */
ssdv_out_jpeg_int(s, 15, 0);
s->acpart += 15;
}
else
{
/* Next bits are an integer value */
s->state = J_INT;
s->acpart += symbol >> 4;
s->needbits = symbol & 0x0F;
}
}
/* Clear processed bits */
s->worklen -= width;
s->workbits &= (1 << s->worklen) - 1;
}
else if(s->state == J_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 */
{
s->dc[s->component] += i;
if(s->mcupart == 0 || s->mcupart == 4 || s->mcupart == 5)
{
/* Output absolute DC value */
ssdv_out_jpeg_int(s, 0, s->dc[s->component]);
}
else
{
/* Output relative DC value */
ssdv_out_jpeg_int(s, 0, i);
}
}
else /* AC */
{
/* Output AC codes directly */
ssdv_out_jpeg_int(s, 0, i); /* RLE? */
}
/* Next AC part to expect */
s->acpart++;
/* Next bits are a huffman code */
s->state = J_HUFF;
/* Clear processed bits */
s->worklen -= s->needbits;
s->workbits &= (1 << s->worklen) - 1;
}
if(s->acpart >= 64)
{
/* Reached the end of this MCU part */
if(++s->mcupart == 6)
{
s->mcupart = 0;
s->mcu_id++;
/* Test for the end of image */
if(s->mcu_id >= s->mcu_count) return(SSDV_EOI);
/* Set the packet MCU marker - encoder only */
if(s->packet_mcu_id == 0xFFFF)
{
s->packet_mcu_id = s->mcu_id;
s->packet_mcu_offset =
(SSDV_PKT_SIZE_PAYLOAD - s->out_len) * 8 + s->outlen;
}
}
if(s->mcupart < 4) s->component = 0;
else s->component = s->mcupart - 3;
s->acpart = 0;
}
if(s->out_len == 0) return(SSDV_BUFFER_FULL);
return(SSDV_OK);
}
/*****************************************************************************/
static char ssdv_have_marker(ssdv_t *s)
{
switch(s->marker)
{
case J_SOF0:
case J_SOS:
/* Copy the data before processing */
if(s->marker_len > HBUFF_LEN)
{
/* Not enough memory ... shouldn't happen! */
return(SSDV_ERROR);
}
s->marker_data = s->hbuff;
s->marker_data_len = 0;
s->state = J_MARKER_DATA;
break;
default:
/* Ignore other marks, skipping any associated data */
s->in_skip = s->marker_len;
s->state = J_MARKER;
break;
}
return(SSDV_OK);
}
static char ssdv_have_marker_data(ssdv_t *s)
{
uint8_t *d = s->marker_data;
switch(s->marker)
{
case J_SOF0:
s->width = (d[3] << 8) | d[4];
s->height = (d[1] << 8) | d[2];
/* Calculate number of MCU blocks in this image -- assumes 16x16 blocks */
s->mcu_count = (s->width >> 4) * (s->height >> 4);
/* The image must have a precision of 8 */
if(d[0] != 8) return(SSDV_ERROR);
/* The image must have 3 components (Y'Cb'Cr) */
if(d[5] != 3) return(SSDV_ERROR);
/* The image dimensions must be a multiple of 16 */
if((s->width & 0x0F) || (s->height & 0x0F)) return(SSDV_ERROR);
break;
case J_SOS:
/* The image must have 3 components (Y'Cb'Cr) */
if(d[0] != 3) return(SSDV_ERROR);
/* The SOS data is followed by the image data */
s->state = J_HUFF;
return(SSDV_OK);
}
s->state = J_MARKER;
return(SSDV_OK);
}
char ssdv_enc_init(ssdv_t *s, uint8_t image_id)
{
memset(s, 0, sizeof(ssdv_t));
s->image_id = image_id;
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 = SSDV_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;
/* 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 J_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;
ssdv_have_marker(s);
}
else if(s->marker >= J_SOF0 && s->marker <= J_COM)
{
/* All other markers are followed by data */
s->marker_len = 0;
s->state = J_MARKER_LEN;
s->needbits = 16;
}
break;
case J_MARKER_LEN:
s->marker_len = (s->marker_len << 8) | b;
if((s->needbits -= 8) == 0)
{
s->marker_len -= 2;
ssdv_have_marker(s);
}
break;
case J_MARKER_DATA:
s->marker_data[s->marker_data_len++] = b;
if(s->marker_data_len == s->marker_len)
{
ssdv_have_marker_data(s);
}
break;
case J_HUFF:
case J_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;
uint16_t mcu_offset = s->packet_mcu_offset;
if(mcu_offset != 0xFFFF && mcu_offset >= SSDV_PKT_SIZE_PAYLOAD * 8)
{
/* The first MCU begins in the next packet, not this one */
mcu_id = mcu_offset = 0xFFFF;
s->packet_mcu_offset -= SSDV_PKT_SIZE_PAYLOAD * 8;
}
else
{
/* Clear the MCU data for the next packet */
s->packet_mcu_id = s->packet_mcu_offset = 0xFFFF;
}
/* A packet is ready, create the headers */
s->out[0] = 0x55; /* Sync */
s->out[1] = 0x66; /* Type */
s->out[2] = s->image_id; /* Image ID */
s->out[3] = s->packet_id >> 8; /* Packet ID MSB */
s->out[4] = s->packet_id & 0xFF; /* Packet ID LSB */
s->out[5] = s->width >> 4; /* Width / 16 */
s->out[6] = s->height >> 4; /* Height / 16 */
s->out[7] = mcu_offset >> 8; /* Next MCU offset MSB */
s->out[8] = mcu_offset & 0xFF; /* Next MCU offset LSB */
s->out[9] = mcu_id >> 8; /* MCU ID MSB */
s->out[10] = mcu_id & 0xFF; /* MCU ID LSB */
/* Generate the RS codes */
encode_rs_8(&s->out[1], &s->out[SSDV_PKT_SIZE - SSDV_PKT_SIZE_RSCODES], 0);
s->packet_id++;
/* Have we reached the end of the image data? */
if(r == SSDV_EOI) s->state = J_MARKER;
return(SSDV_OK);
}
else if(r != SSDV_FEED_ME)
{
/* An error occured */
return(SSDV_ERROR);
}
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);
}
/*****************************************************************************/

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/* hadie - High Altitude Balloon flight software */
/*============================================================*/
/* Copyright (C)2010 Philip Heron <phil@sanslogic.co.uk> */
/* */
/* This program is distributed under the terms of the GNU */
/* General Public License, version 2. You may use, modify, */
/* and redistribute it under the terms of this license. A */
/* copy should be included with this source. */
#include <stdint.h>
#ifndef INC_SSDV_H
#define INC_SSDV_H
#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_RSCODES (0x20)
#define SSDV_PKT_SIZE_PAYLOAD (SSDV_PKT_SIZE - SSDV_PKT_SIZE_HEADER - 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 */
/* Output bits */
uint32_t outbits; /* Output bit buffer */
uint8_t outlen; /* Number of bits in the output bit buffer */
/* JPEG decoder state */
enum { J_MARKER = 0, J_MARKER_LEN, J_MARKER_DATA, J_HUFF, J_INT } 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 */
unsigned char component; /* 0 = Y, 1 = Cb, 2 = Cr */
unsigned char mcupart; /* 0-3 = Y, 4 = Cb, 5 = Cr */
unsigned char acpart; /* 0 - 64; 0 = DC, 1 - 64 = AC */
int dc[COMPONENTS]; /* DC value for each component */
unsigned char needbits; /* Number of bits needed to decode integer */
/* Small buffer for reading SOF0 and SOS header data into */
uint8_t hbuff[HBUFF_LEN];
} ssdv_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, size_t *length);
#ifdef __cplusplus
}
#endif
#endif