File: dec_jpeg.c

package info (click to toggle)
fswebcam 20140113-2
  • links: PTS, VCS
  • area: main
  • in suites: bullseye, buster, sid
  • size: 612 kB
  • sloc: ansic: 8,442; makefile: 58
file content (141 lines) | stat: -rw-r--r-- 5,088 bytes parent folder | download | duplicates (3)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
/* fswebcam - Small and simple webcam for *nix                */
/*============================================================*/
/* Copyright (C)2005-2011 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.                  */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <string.h>
#include <stdlib.h>
#include <stdint.h>
#include <gd.h>
#include "fswebcam.h"
#include "src.h"
#include "log.h"

int verify_jpeg_dht(uint8_t *src,  uint32_t lsrc,
                    uint8_t **dst, uint32_t *ldst)
{
	/* This function is based on a patch provided by Scott J. Bertin. */
	
	static unsigned char dht[] =
	{
		0xff, 0xc4, 0x01, 0xa2, 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, 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, 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, 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
	};
	uint8_t *p, *i = NULL;
	
	/* By default we simply return the source image. */
	*dst = src;
	*ldst = lsrc;
	
	/* Scan for an existing DHT segment or the first SOS segment. */
	for(p = src + 2; p - src < lsrc - 3 && i == NULL; )
	{
		if(*(p++) != 0xFF) continue;
		
		if(*p == 0xD9) break;           /* JPEG_EOI */
		if(*p == 0xC4) return(0);       /* JPEG_DHT */
		if(*p == 0xDA && !i) i = p - 1; /* JPEG_SOS */
		
		/* Move to next segment. */
		p += (p[1] << 8) + p[2];
	}
	
	/* If no SOS was found, insert the DHT directly after the SOI. */
	if(i == NULL) i = src + 2;
	
	DEBUG("Inserting DHT segment into JPEG frame.");
	
	*ldst = lsrc + sizeof(dht);
	*dst  = malloc(*ldst);
	if(!*dst)
	{
		ERROR("Out of memory.");
		return(-1);
	}
	
	/* Copy the JPEG data, inserting the DHT segment. */
	memcpy((p  = *dst), src, i - src);
	memcpy((p += i - src), dht, sizeof(dht));
	memcpy((p += sizeof(dht)), i, lsrc - (i - src));
	
	return(1);
}

int fswc_add_image_jpeg(src_t *src, avgbmp_t *abitmap)
{
	uint32_t x, y, hlength;
	uint8_t *himg = NULL;
	gdImage *im;
	int i;
	
	/* MJPEG data may lack the DHT segment required for decoding... */
	i = verify_jpeg_dht(src->img, src->length, &himg, &hlength);
	
	im = gdImageCreateFromJpegPtr(hlength, himg);
	if(i == 1) free(himg);
	
	if(!im) return(-1);
	
	for(y = 0; y < src->height; y++)
		for(x = 0; x < src->width; x++)
		{
			int c = gdImageGetPixel(im, x, y);
			
			*(abitmap++) += (c & 0xFF0000) >> 16;
			*(abitmap++) += (c & 0x00FF00) >> 8;
			*(abitmap++) += (c & 0x0000FF);
		}
	
	gdImageDestroy(im);
	
	return(0);
}