diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /Documentation/video4linux/CQcam.txt |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'Documentation/video4linux/CQcam.txt')
-rw-r--r-- | Documentation/video4linux/CQcam.txt | 412 |
1 files changed, 412 insertions, 0 deletions
diff --git a/Documentation/video4linux/CQcam.txt b/Documentation/video4linux/CQcam.txt new file mode 100644 index 000000000000..e415e3604539 --- /dev/null +++ b/Documentation/video4linux/CQcam.txt | |||
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1 | c-qcam - Connectix Color QuickCam video4linux kernel driver | ||
2 | |||
3 | Copyright (C) 1999 Dave Forrest <drf5n@virginia.edu> | ||
4 | released under GNU GPL. | ||
5 | |||
6 | 1999-12-08 Dave Forrest, written with kernel version 2.2.12 in mind | ||
7 | |||
8 | |||
9 | Table of Contents | ||
10 | |||
11 | 1.0 Introduction | ||
12 | 2.0 Compilation, Installation, and Configuration | ||
13 | 3.0 Troubleshooting | ||
14 | 4.0 Future Work / current work arounds | ||
15 | 9.0 Sample Program, v4lgrab | ||
16 | 10.0 Other Information | ||
17 | |||
18 | |||
19 | 1.0 Introduction | ||
20 | |||
21 | The file ../drivers/char/c-qcam.c is a device driver for the | ||
22 | Logitech (nee Connectix) parallel port interface color CCD camera. | ||
23 | This is a fairly inexpensive device for capturing images. Logitech | ||
24 | does not currently provide information for developers, but many people | ||
25 | have engineered several solutions for non-Microsoft use of the Color | ||
26 | Quickcam. | ||
27 | |||
28 | 1.1 Motivation | ||
29 | |||
30 | I spent a number of hours trying to get my camera to work, and I | ||
31 | hope this document saves you some time. My camera will not work with | ||
32 | the 2.2.13 kernel as distributed, but with a few patches to the | ||
33 | module, I was able to grab some frames. See 4.0, Future Work. | ||
34 | |||
35 | |||
36 | |||
37 | 2.0 Compilation, Installation, and Configuration | ||
38 | |||
39 | The c-qcam depends on parallel port support, video4linux, and the | ||
40 | Color Quickcam. It is also nice to have the parallel port readback | ||
41 | support enabled. I enabled these as modules during the kernel | ||
42 | configuration. The appropriate flags are: | ||
43 | |||
44 | CONFIG_PRINTER M for lp.o, parport.o parport_pc.o modules | ||
45 | CONFIG_PNP_PARPORT M for autoprobe.o IEEE1284 readback module | ||
46 | CONFIG_PRINTER_READBACK M for parport_probe.o IEEE1284 readback module | ||
47 | CONFIG_VIDEO_DEV M for videodev.o video4linux module | ||
48 | CONFIG_VIDEO_CQCAM M for c-qcam.o Color Quickcam module | ||
49 | |||
50 | With these flags, the kernel should compile and install the modules. | ||
51 | To record and monitor the compilation, I use: | ||
52 | |||
53 | (make zlilo ; \ | ||
54 | make modules; \ | ||
55 | make modules_install ; | ||
56 | depmod -a ) &>log & | ||
57 | less log # then a capital 'F' to watch the progress | ||
58 | |||
59 | But that is my personal preference. | ||
60 | |||
61 | 2.2 Configuration | ||
62 | |||
63 | The configuration requires module configuration and device | ||
64 | configuration. I like kmod or kerneld process with the | ||
65 | /etc/modprobe.conf file so the modules can automatically load/unload as | ||
66 | they are used. The video devices could already exist, be generated | ||
67 | using MAKEDEV, or need to be created. The following sections detail | ||
68 | these procedures. | ||
69 | |||
70 | |||
71 | 2.1 Module Configuration | ||
72 | |||
73 | Using modules requires a bit of work to install and pass the | ||
74 | parameters. Understand that entries in /etc/modprobe.conf of: | ||
75 | |||
76 | alias parport_lowlevel parport_pc | ||
77 | options parport_pc io=0x378 irq=none | ||
78 | alias char-major-81 videodev | ||
79 | alias char-major-81-0 c-qcam | ||
80 | |||
81 | will cause the kmod/modprobe to do certain things. If you are | ||
82 | using kmod, then a request for a 'char-major-81-0' will cause | ||
83 | the 'c-qcam' module to load. If you have other video sources with | ||
84 | modules, you might want to assign the different minor numbers to | ||
85 | different modules. | ||
86 | |||
87 | 2.2 Device Configuration | ||
88 | |||
89 | At this point, we need to ensure that the device files exist. | ||
90 | Video4linux used the /dev/video* files, and we want to attach the | ||
91 | Quickcam to one of these. | ||
92 | |||
93 | ls -lad /dev/video* # should produce a list of the video devices | ||
94 | |||
95 | If the video devices do not exist, you can create them with: | ||
96 | |||
97 | su | ||
98 | cd /dev | ||
99 | for ii in 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 ; do | ||
100 | mknod video$ii c 81 $ii # char-major-81-[0-16] | ||
101 | chown root.root video$ii # owned by root | ||
102 | chmod 600 video$ii # read/writable by root only | ||
103 | done | ||
104 | |||
105 | Lots of people connect video0 to video and bttv, but you might want | ||
106 | your c-qcam to mean something more: | ||
107 | |||
108 | ln -s video0 c-qcam # make /dev/c-qcam a working file | ||
109 | ln -s c-qcam video # make /dev/c-qcam your default video source | ||
110 | |||
111 | But these are conveniences. The important part is to make the proper | ||
112 | special character files with the right major and minor numbers. All | ||
113 | of the special device files are listed in ../devices.txt. If you | ||
114 | would like the c-qcam readable by non-root users, you will need to | ||
115 | change the permissions. | ||
116 | |||
117 | 3.0 Troubleshooting | ||
118 | |||
119 | If the sample program below, v4lgrab, gives you output then | ||
120 | everything is working. | ||
121 | |||
122 | v4lgrab | wc # should give you a count of characters | ||
123 | |||
124 | Otherwise, you have some problem. | ||
125 | |||
126 | The c-qcam is IEEE1284 compatible, so if you are using the proc file | ||
127 | system (CONFIG_PROC_FS), the parallel printer support | ||
128 | (CONFIG_PRINTER), the IEEE 1284 system,(CONFIG_PRINTER_READBACK), you | ||
129 | should be able to read some identification from your quickcam with | ||
130 | |||
131 | modprobe -v parport | ||
132 | modprobe -v parport_probe | ||
133 | cat /proc/parport/PORTNUMBER/autoprobe | ||
134 | Returns: | ||
135 | CLASS:MEDIA; | ||
136 | MODEL:Color QuickCam 2.0; | ||
137 | MANUFACTURER:Connectix; | ||
138 | |||
139 | A good response to this indicates that your color quickcam is alive | ||
140 | and well. A common problem is that the current driver does not | ||
141 | reliably detect a c-qcam, even though one is attached. In this case, | ||
142 | |||
143 | modprobe -v c-qcam | ||
144 | or | ||
145 | insmod -v c-qcam | ||
146 | |||
147 | Returns a message saying "Device or resource busy" Development is | ||
148 | currently underway, but a workaround is to patch the module to skip | ||
149 | the detection code and attach to a defined port. Check the | ||
150 | video4linux mailing list and archive for more current information. | ||
151 | |||
152 | 3.1 Checklist: | ||
153 | |||
154 | Can you get an image? | ||
155 | v4lgrab >qcam.ppm ; wc qcam.ppm ; xv qcam.ppm | ||
156 | |||
157 | Is a working c-qcam connected to the port? | ||
158 | grep ^ /proc/parport/?/autoprobe | ||
159 | |||
160 | Do the /dev/video* files exist? | ||
161 | ls -lad /dev/video | ||
162 | |||
163 | Is the c-qcam module loaded? | ||
164 | modprobe -v c-qcam ; lsmod | ||
165 | |||
166 | Does the camera work with alternate programs? cqcam, etc? | ||
167 | |||
168 | |||
169 | |||
170 | |||
171 | 4.0 Future Work / current workarounds | ||
172 | |||
173 | It is hoped that this section will soon become obsolete, but if it | ||
174 | isn't, you might try patching the c-qcam module to add a parport=xxx | ||
175 | option as in the bw-qcam module so you can specify the parallel port: | ||
176 | |||
177 | insmod -v c-qcam parport=0 | ||
178 | |||
179 | And bypass the detection code, see ../../drivers/char/c-qcam.c and | ||
180 | look for the 'qc_detect' code and call. | ||
181 | |||
182 | Note that there is work in progress to change the video4linux API, | ||
183 | this work is documented at the video4linux2 site listed below. | ||
184 | |||
185 | |||
186 | 9.0 --- A sample program using v4lgrabber, | ||
187 | |||
188 | This program is a simple image grabber that will copy a frame from the | ||
189 | first video device, /dev/video0 to standard output in portable pixmap | ||
190 | format (.ppm) Using this like: 'v4lgrab | convert - c-qcam.jpg' | ||
191 | produced this picture of me at | ||
192 | http://mug.sys.virginia.edu/~drf5n/extras/c-qcam.jpg | ||
193 | |||
194 | -------------------- 8< ---------------- 8< ----------------------------- | ||
195 | |||
196 | /* Simple Video4Linux image grabber. */ | ||
197 | /* | ||
198 | * Video4Linux Driver Test/Example Framegrabbing Program | ||
199 | * | ||
200 | * Compile with: | ||
201 | * gcc -s -Wall -Wstrict-prototypes v4lgrab.c -o v4lgrab | ||
202 | * Use as: | ||
203 | * v4lgrab >image.ppm | ||
204 | * | ||
205 | * Copyright (C) 1998-05-03, Phil Blundell <philb@gnu.org> | ||
206 | * Copied from http://www.tazenda.demon.co.uk/phil/vgrabber.c | ||
207 | * with minor modifications (Dave Forrest, drf5n@virginia.edu). | ||
208 | * | ||
209 | */ | ||
210 | |||
211 | #include <unistd.h> | ||
212 | #include <sys/types.h> | ||
213 | #include <sys/stat.h> | ||
214 | #include <fcntl.h> | ||
215 | #include <stdio.h> | ||
216 | #include <sys/ioctl.h> | ||
217 | #include <stdlib.h> | ||
218 | |||
219 | #include <linux/types.h> | ||
220 | #include <linux/videodev.h> | ||
221 | |||
222 | #define FILE "/dev/video0" | ||
223 | |||
224 | /* Stole this from tvset.c */ | ||
225 | |||
226 | #define READ_VIDEO_PIXEL(buf, format, depth, r, g, b) \ | ||
227 | { \ | ||
228 | switch (format) \ | ||
229 | { \ | ||
230 | case VIDEO_PALETTE_GREY: \ | ||
231 | switch (depth) \ | ||
232 | { \ | ||
233 | case 4: \ | ||
234 | case 6: \ | ||
235 | case 8: \ | ||
236 | (r) = (g) = (b) = (*buf++ << 8);\ | ||
237 | break; \ | ||
238 | \ | ||
239 | case 16: \ | ||
240 | (r) = (g) = (b) = \ | ||
241 | *((unsigned short *) buf); \ | ||
242 | buf += 2; \ | ||
243 | break; \ | ||
244 | } \ | ||
245 | break; \ | ||
246 | \ | ||
247 | \ | ||
248 | case VIDEO_PALETTE_RGB565: \ | ||
249 | { \ | ||
250 | unsigned short tmp = *(unsigned short *)buf; \ | ||
251 | (r) = tmp&0xF800; \ | ||
252 | (g) = (tmp<<5)&0xFC00; \ | ||
253 | (b) = (tmp<<11)&0xF800; \ | ||
254 | buf += 2; \ | ||
255 | } \ | ||
256 | break; \ | ||
257 | \ | ||
258 | case VIDEO_PALETTE_RGB555: \ | ||
259 | (r) = (buf[0]&0xF8)<<8; \ | ||
260 | (g) = ((buf[0] << 5 | buf[1] >> 3)&0xF8)<<8; \ | ||
261 | (b) = ((buf[1] << 2 ) & 0xF8)<<8; \ | ||
262 | buf += 2; \ | ||
263 | break; \ | ||
264 | \ | ||
265 | case VIDEO_PALETTE_RGB24: \ | ||
266 | (r) = buf[0] << 8; (g) = buf[1] << 8; \ | ||
267 | (b) = buf[2] << 8; \ | ||
268 | buf += 3; \ | ||
269 | break; \ | ||
270 | \ | ||
271 | default: \ | ||
272 | fprintf(stderr, \ | ||
273 | "Format %d not yet supported\n", \ | ||
274 | format); \ | ||
275 | } \ | ||
276 | } | ||
277 | |||
278 | int get_brightness_adj(unsigned char *image, long size, int *brightness) { | ||
279 | long i, tot = 0; | ||
280 | for (i=0;i<size*3;i++) | ||
281 | tot += image[i]; | ||
282 | *brightness = (128 - tot/(size*3))/3; | ||
283 | return !((tot/(size*3)) >= 126 && (tot/(size*3)) <= 130); | ||
284 | } | ||
285 | |||
286 | int main(int argc, char ** argv) | ||
287 | { | ||
288 | int fd = open(FILE, O_RDONLY), f; | ||
289 | struct video_capability cap; | ||
290 | struct video_window win; | ||
291 | struct video_picture vpic; | ||
292 | |||
293 | unsigned char *buffer, *src; | ||
294 | int bpp = 24, r, g, b; | ||
295 | unsigned int i, src_depth; | ||
296 | |||
297 | if (fd < 0) { | ||
298 | perror(FILE); | ||
299 | exit(1); | ||
300 | } | ||
301 | |||
302 | if (ioctl(fd, VIDIOCGCAP, &cap) < 0) { | ||
303 | perror("VIDIOGCAP"); | ||
304 | fprintf(stderr, "(" FILE " not a video4linux device?)\n"); | ||
305 | close(fd); | ||
306 | exit(1); | ||
307 | } | ||
308 | |||
309 | if (ioctl(fd, VIDIOCGWIN, &win) < 0) { | ||
310 | perror("VIDIOCGWIN"); | ||
311 | close(fd); | ||
312 | exit(1); | ||
313 | } | ||
314 | |||
315 | if (ioctl(fd, VIDIOCGPICT, &vpic) < 0) { | ||
316 | perror("VIDIOCGPICT"); | ||
317 | close(fd); | ||
318 | exit(1); | ||
319 | } | ||
320 | |||
321 | if (cap.type & VID_TYPE_MONOCHROME) { | ||
322 | vpic.depth=8; | ||
323 | vpic.palette=VIDEO_PALETTE_GREY; /* 8bit grey */ | ||
324 | if(ioctl(fd, VIDIOCSPICT, &vpic) < 0) { | ||
325 | vpic.depth=6; | ||
326 | if(ioctl(fd, VIDIOCSPICT, &vpic) < 0) { | ||
327 | vpic.depth=4; | ||
328 | if(ioctl(fd, VIDIOCSPICT, &vpic) < 0) { | ||
329 | fprintf(stderr, "Unable to find a supported capture format.\n"); | ||
330 | close(fd); | ||
331 | exit(1); | ||
332 | } | ||
333 | } | ||
334 | } | ||
335 | } else { | ||
336 | vpic.depth=24; | ||
337 | vpic.palette=VIDEO_PALETTE_RGB24; | ||
338 | |||
339 | if(ioctl(fd, VIDIOCSPICT, &vpic) < 0) { | ||
340 | vpic.palette=VIDEO_PALETTE_RGB565; | ||
341 | vpic.depth=16; | ||
342 | |||
343 | if(ioctl(fd, VIDIOCSPICT, &vpic)==-1) { | ||
344 | vpic.palette=VIDEO_PALETTE_RGB555; | ||
345 | vpic.depth=15; | ||
346 | |||
347 | if(ioctl(fd, VIDIOCSPICT, &vpic)==-1) { | ||
348 | fprintf(stderr, "Unable to find a supported capture format.\n"); | ||
349 | return -1; | ||
350 | } | ||
351 | } | ||
352 | } | ||
353 | } | ||
354 | |||
355 | buffer = malloc(win.width * win.height * bpp); | ||
356 | if (!buffer) { | ||
357 | fprintf(stderr, "Out of memory.\n"); | ||
358 | exit(1); | ||
359 | } | ||
360 | |||
361 | do { | ||
362 | int newbright; | ||
363 | read(fd, buffer, win.width * win.height * bpp); | ||
364 | f = get_brightness_adj(buffer, win.width * win.height, &newbright); | ||
365 | if (f) { | ||
366 | vpic.brightness += (newbright << 8); | ||
367 | if(ioctl(fd, VIDIOCSPICT, &vpic)==-1) { | ||
368 | perror("VIDIOSPICT"); | ||
369 | break; | ||
370 | } | ||
371 | } | ||
372 | } while (f); | ||
373 | |||
374 | fprintf(stdout, "P6\n%d %d 255\n", win.width, win.height); | ||
375 | |||
376 | src = buffer; | ||
377 | |||
378 | for (i = 0; i < win.width * win.height; i++) { | ||
379 | READ_VIDEO_PIXEL(src, vpic.palette, src_depth, r, g, b); | ||
380 | fputc(r>>8, stdout); | ||
381 | fputc(g>>8, stdout); | ||
382 | fputc(b>>8, stdout); | ||
383 | } | ||
384 | |||
385 | close(fd); | ||
386 | return 0; | ||
387 | } | ||
388 | -------------------- 8< ---------------- 8< ----------------------------- | ||
389 | |||
390 | |||
391 | 10.0 --- Other Information | ||
392 | |||
393 | Use the ../../Maintainers file, particularly the VIDEO FOR LINUX and PARALLEL | ||
394 | PORT SUPPORT sections | ||
395 | |||
396 | The video4linux page: | ||
397 | http://roadrunner.swansea.linux.org.uk/v4l.shtml | ||
398 | |||
399 | The video4linux2 page: | ||
400 | http://millennium.diads.com/bdirks/v4l2.htm | ||
401 | |||
402 | Some web pages about the quickcams: | ||
403 | http://www.dkfz-heidelberg.de/Macromol/wedemann/mini-HOWTO-cqcam.html | ||
404 | |||
405 | http://www.crynwr.com/qcpc/ QuickCam Third-Party Drivers | ||
406 | http://www.crynwr.com/qcpc/re.html Some Reverse Engineering | ||
407 | http://cse.unl.edu/~cluening/gqcam/ v4l client | ||
408 | http://phobos.illtel.denver.co.us/pub/qcread/ doesn't use v4l | ||
409 | ftp://ftp.cs.unm.edu/pub/chris/quickcam/ Has lots of drivers | ||
410 | http://www.cs.duke.edu/~reynolds/quickcam/ Has lots of information | ||
411 | |||
412 | |||