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
142
143
144
145
146
147
148
149
|
/* Linux driver for Philips webcam
Decompression frontend.
(C) 1999-2003 Nemosoft Unv.
(C) 2004 Luc Saillard (luc@saillard.org)
NOTE: this version of pwc is an unofficial (modified) release of pwc & pcwx
driver and thus may have bugs that are not present in the original version.
Please send bug reports and support requests to <luc@saillard.org>.
The decompression routines have been implemented by reverse-engineering the
Nemosoft binary pwcx module. Caveat emptor.
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 2 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, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <asm/current.h>
#include <asm/types.h>
#include "pwc.h"
#include "pwc-uncompress.h"
#include "pwc-dec1.h"
#include "pwc-dec23.h"
int pwc_decompress(struct pwc_device *pdev)
{
struct pwc_frame_buf *fbuf;
int n, line, col, stride;
void *yuv, *image;
u16 *src;
u16 *dsty, *dstu, *dstv;
if (pdev == NULL)
return -EFAULT;
#if defined(__KERNEL__) && defined(PWC_MAGIC)
if (pdev->magic != PWC_MAGIC) {
Err("pwc_decompress(): magic failed.\n");
return -EFAULT;
}
#endif
fbuf = pdev->read_frame;
if (fbuf == NULL)
return -EFAULT;
image = pdev->image_ptr[pdev->fill_image];
if (!image)
return -EFAULT;
yuv = fbuf->data + pdev->frame_header_size; /* Skip header */
/* Raw format; that's easy... */
if (pdev->vpalette == VIDEO_PALETTE_RAW)
{
memcpy(image, yuv, pdev->frame_size);
return 0;
}
if (pdev->vbandlength == 0) {
/* Uncompressed mode. We copy the data into the output buffer,
using the viewport size (which may be larger than the image
size). Unfortunately we have to do a bit of byte stuffing
to get the desired output format/size.
*/
/*
* We do some byte shuffling here to go from the
* native format to YUV420P.
*/
src = (u16 *)yuv;
n = pdev->view.x * pdev->view.y;
/* offset in Y plane */
stride = pdev->view.x * pdev->offset.y + pdev->offset.x;
dsty = (u16 *)(image + stride);
/* offsets in U/V planes */
stride = pdev->view.x * pdev->offset.y / 4 + pdev->offset.x / 2;
dstu = (u16 *)(image + n + stride);
dstv = (u16 *)(image + n + n / 4 + stride);
/* increment after each line */
stride = (pdev->view.x - pdev->image.x) / 2; /* u16 is 2 bytes */
for (line = 0; line < pdev->image.y; line++) {
for (col = 0; col < pdev->image.x; col += 4) {
*dsty++ = *src++;
*dsty++ = *src++;
if (line & 1)
*dstv++ = *src++;
else
*dstu++ = *src++;
}
dsty += stride;
if (line & 1)
dstv += (stride >> 1);
else
dstu += (stride >> 1);
}
}
else {
/* Compressed; the decompressor routines will write the data
in planar format immediately.
*/
int flags;
flags = PWCX_FLAG_PLANAR;
if (pdev->vsize == PSZ_VGA && pdev->vframes == 5 && pdev->vsnapshot)
{
printk(KERN_ERR "pwc: Mode Bayer is not supported for now\n");
flags |= PWCX_FLAG_BAYER;
return -ENXIO; /* No such device or address: missing decompressor */
}
switch (pdev->type)
{
#if 0
case 675:
case 680:
case 690:
case 720:
case 730:
case 740:
case 750:
pwc_dec23_decompress(&pdev->image, &pdev->view, &pdev->offset,
yuv, image,
flags,
pdev->decompress_data, pdev->vbandlength);
break;
case 645:
case 646:
/* TODO & FIXME */
#endif
return -ENXIO; /* No such device or address: missing decompressor */
break;
}
}
return 0;
}
|
