2 W996[87]CF JPEG USB Dual Mode Camera Chip
3 Driver for Linux 2.6 (basic version)
4 =========================================
15 5. Module dependencies
18 8. Contact information
24 Copyright (C) 2002-2004 by Luca Risolia <luca.risolia@studio.unibo.it>
26 Winbond is a trademark of Winbond Electronics Corporation.
27 This driver is not sponsored or developed by Winbond.
32 This program is free software; you can redistribute it and/or modify
33 it under the terms of the GNU General Public License as published by
34 the Free Software Foundation; either version 2 of the License, or
35 (at your option) any later version.
37 This program is distributed in the hope that it will be useful,
38 but WITHOUT ANY WARRANTY; without even the implied warranty of
39 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
40 GNU General Public License for more details.
42 You should have received a copy of the GNU General Public License
43 along with this program; if not, write to the Free Software
44 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
49 This driver supports the video streaming capabilities of the devices mounting
50 Winbond W9967CF and Winbond W9968CF JPEG USB Dual Mode Camera Chips. OV681
51 based cameras should be supported as well.
53 The driver is divided into two modules: the basic one, "w9968cf", is needed for
54 the supported devices to work; the second one, "w9968cf-vpp", is an optional
55 module, which provides some useful video post-processing functions like video
56 decoding, up-scaling and colour conversions. Once the driver is installed,
57 every time an application tries to open a recognized device, "w9968cf" checks
58 the presence of the "w9968cf-vpp" module and loads it automatically by default.
60 Please keep in mind that official kernels do NOT include the second module for
61 performance purposes. However it is always recommended to download and install
62 the latest and complete release of the driver, replacing the existing one, if
63 present: it will be still even possible not to load the "w9968cf-vpp" module at
64 all, if you ever want to. Another important missing feature of the version in
65 the official Linux 2.4 kernels is the writeable /proc filesystem interface.
67 The latest and full-featured version of the W996[87]CF driver can be found at:
68 http://go.lamarinapunto.com/ . Please refer to the documentation included in
69 that package, if you are going to use it.
71 Up to 32 cameras can be handled at the same time. They can be connected and
72 disconnected from the host many times without turning off the computer, if
73 your system supports the hotplug facility.
75 To change the default settings for each camera, many parameters can be passed
76 through command line when the module is loaded into memory.
78 The driver relies on the Video4Linux, USB and I2C core modules. It has been
79 designed to run properly on SMP systems as well. An additional module,
80 "ovcamchip", is mandatory; it provides support for some OmniVision image
81 sensors connected to the W996[87]CF chips; if found in the system, the module
82 will be automatically loaded by default (provided that the kernel has been
83 compiled with the automatic module loading option).
88 At the moment, known W996[87]CF and OV681 based devices are:
89 - Aroma Digi Pen VGA Dual Mode ADG-5000 (unknown image sensor)
90 - AVerMedia AVerTV USB (SAA7111A, Philips FI1216Mk2 tuner, PT2313L audio chip)
91 - Creative Labs Video Blaster WebCam Go (OmniVision OV7610 sensor)
92 - Creative Labs Video Blaster WebCam Go Plus (OmniVision OV7620 sensor)
93 - Lebon LDC-035A (unknown image sensor)
94 - Ezonics EZ-802 EZMega Cam (OmniVision OV8610C sensor)
95 - OmniVision OV8610-EDE (OmniVision OV8610 sensor)
96 - OPCOM Digi Pen VGA Dual Mode Pen Camera (unknown image sensor)
97 - Pretec Digi Pen-II (OmniVision OV7620 sensor)
98 - Pretec DigiPen-480 (OmniVision OV8610 sensor)
100 If you know any other W996[87]CF or OV681 based cameras, please contact me.
102 The list above does NOT imply that all those devices work with this driver: up
103 until now only webcams that have an image sensor supported by the "ovcamchip"
105 For a list of supported image sensors, please visit the author's homepage on
106 this module: http://alpha.dyndns.org/ov511/
108 Possible external microcontrollers of those webcams are not supported: this
109 means that still images cannot be downloaded from the device memory.
111 Furthermore, it's worth to note that I was only able to run tests on my
112 "Creative Labs Video Blaster WebCam Go". Donations of other models, for
113 additional testing and full support, would be much appreciated.
116 5. Module dependencies
117 ======================
118 For it to work properly, the driver needs kernel support for Video4Linux, USB
119 and I2C, and the "ovcamchip" module for the image sensor. Make sure you are not
120 actually using any external "ovcamchip" module, given that the W996[87]CF
121 driver depends on the version of the module present in the official kernels.
123 The following options of the kernel configuration file must be enabled and
124 corresponding modules must be compiled:
134 The I2C core module can be compiled statically in the kernel as well.
136 # OmniVision Camera Chip support
138 CONFIG_VIDEO_OVCAMCHIP=m
144 In addition, depending on the hardware being used, only one of the modules
147 # USB Host Controller Drivers
149 CONFIG_USB_EHCI_HCD=m
150 CONFIG_USB_UHCI_HCD=m
151 CONFIG_USB_OHCI_HCD=m
155 # USB Multimedia devices
162 To use the driver, it is necessary to load the "w9968cf" module into memory
163 after every other module required.
165 Loading can be done this way, from root:
167 [root@localhost home]# modprobe usbcore
168 [root@localhost home]# modprobe i2c-core
169 [root@localhost home]# modprobe w9968cf
171 At this point the pertinent devices should be recognized: "dmesg" can be used
172 to analyze kernel messages:
174 [user@localhost home]$ dmesg
176 There are a lot of parameters the module can use to change the default
177 settings for each device. To list every possible parameter with a brief
178 explanation about them and which syntax to use, it is recommended to run the
181 [root@locahost home]# modinfo w9968cf
186 Module parameters are listed below:
187 -------------------------------------------------------------------------------
191 Description: Automatic 'ovcamchip' module loading: 0 disabled, 1 enabled.
192 If enabled, 'insmod' searches for the required 'ovcamchip'
193 module in the system, according to its configuration, and
194 loads that module automatically. This action is performed as
195 once soon as the 'w9968cf' module is loaded into memory.
197 Note: The kernel must be compiled with the CONFIG_KMOD option
198 enabled for the 'ovcamchip' module to be loaded and for
199 this parameter to be present.
200 -------------------------------------------------------------------------------
204 Description: Automatic 'w9968cf-vpp' module loading: 0 disabled, 1 enabled.
205 If enabled, every time an application attempts to open a
206 camera, 'insmod' searches for the video post-processing module
207 in the system and loads it automatically (if present).
208 The optional 'w9968cf-vpp' module adds extra image manipulation
209 capabilities to the 'w9968cf' module,like software up-scaling,
210 colour conversions and video decompression for very high frame
213 Note: The kernel must be compiled with the CONFIG_KMOD option
214 enabled for the 'w9968cf-vpp' module to be loaded and for
215 this parameter to be present.
216 -------------------------------------------------------------------------------
220 Description: Number of cameras allowed to stream simultaneously.
221 n may vary from 0 to 32.
223 -------------------------------------------------------------------------------
225 Type: int array (min = 0, max = 32)
227 Description: Specify V4L minor mode number.
228 -1 = use next available
229 n = use minor number n
230 You can specify up to 32 cameras this way.
232 video_nr=-1,2,-1 would assign minor number 2 to the second
233 recognized camera and use auto for the first one and for every
236 -------------------------------------------------------------------------------
238 Type: int array (min = 0, max = 32)
240 Description: Specify the maximum data payload size in bytes for alternate
241 settings, for each device. n is scaled between 63 and 1023.
243 -------------------------------------------------------------------------------
245 Type: int array (min = 0, max = 32)
247 Description: For advanced users.
248 Specify the maximum number of video frame buffers to allocate
249 for each device, from 2 to 32.
251 -------------------------------------------------------------------------------
253 Type: bool array (min = 0, max = 32)
255 Description: Hardware double buffering: 0 disabled, 1 enabled.
256 It should be enabled if you want smooth video output: if you
257 obtain out of sync. video, disable it, or try to
258 decrease the 'clockdiv' module parameter value.
259 Default: 1 for every device.
260 -------------------------------------------------------------------------------
262 Type: bool array (min = 0, max = 32)
264 Description: Video data clamping: 0 disabled, 1 enabled.
265 Default: 0 for every device.
266 -------------------------------------------------------------------------------
268 Type: int array (min = 0, max = 32)
269 Syntax: <0|1|2[,...]>
270 Description: Video filter type.
271 0 none, 1 (1-2-1) 3-tap filter, 2 (2-3-6-3-2) 5-tap filter.
272 The filter is used to reduce noise and aliasing artifacts
273 produced by the CCD or CMOS image sensor.
274 Default: 0 for every device.
275 -------------------------------------------------------------------------------
277 Type: bool array (min = 0, max = 32)
279 Description: Large view: 0 disabled, 1 enabled.
280 Default: 1 for every device.
281 -------------------------------------------------------------------------------
283 Type: bool array (min = 0, max = 32)
285 Description: Software scaling (for non-compressed video only):
286 0 disabled, 1 enabled.
287 Disable it if you have a slow CPU or you don't have enough
289 Default: 0 for every device.
290 Note: If 'w9968cf-vpp' is not present, this parameter is set to 0.
291 -------------------------------------------------------------------------------
293 Type: int array (min = 0, max = 32)
294 Syntax: <0|1|2[,...]>
295 Description: Software video decompression:
296 0 = disables decompression
297 (doesn't allow formats needing decompression).
298 1 = forces decompression
299 (allows formats needing decompression only).
300 2 = allows any permitted formats.
301 Formats supporting (de)compressed video are YUV422P and
302 YUV420P/YUV420 in any resolutions where width and height are
304 Default: 2 for every device.
305 Note: If 'w9968cf-vpp' is not present, forcing decompression is not
306 allowed; in this case this parameter is set to 2.
307 -------------------------------------------------------------------------------
309 Type: int array (min = 0, max = 32)
310 Syntax: <0|9|10|13|15|8|7|1|6|3|4|5[,...]>
311 Description: Force picture palette.
313 0 = Off - allows any of the following formats:
314 9 = UYVY 16 bpp - Original video, compression disabled
315 10 = YUV420 12 bpp - Original video, compression enabled
316 13 = YUV422P 16 bpp - Original video, compression enabled
317 15 = YUV420P 12 bpp - Original video, compression enabled
318 8 = YUVY 16 bpp - Software conversion from UYVY
319 7 = YUV422 16 bpp - Software conversion from UYVY
320 1 = GREY 8 bpp - Software conversion from UYVY
321 6 = RGB555 16 bpp - Software conversion from UYVY
322 3 = RGB565 16 bpp - Software conversion from UYVY
323 4 = RGB24 24 bpp - Software conversion from UYVY
324 5 = RGB32 32 bpp - Software conversion from UYVY
325 When not 0, this parameter will override 'decompression'.
326 Default: 0 for every device. Initial palette is 9 (UYVY).
327 Note: If 'w9968cf-vpp' is not present, this parameter is set to 9.
328 -------------------------------------------------------------------------------
330 Type: bool array (min = 0, max = 32)
332 Description: Read RGB video data instead of BGR:
333 1 = use RGB component ordering.
334 0 = use BGR component ordering.
335 This parameter has effect when using RGBX palettes only.
336 Default: 0 for every device.
337 -------------------------------------------------------------------------------
339 Type: bool array (min = 0, max = 32)
341 Description: Image sensor automatically changes brightness:
343 Default: 0 for every device.
344 -------------------------------------------------------------------------------
346 Type: bool array (min = 0, max = 32)
348 Description: Image sensor automatically changes exposure:
350 Default: 1 for every device.
351 -------------------------------------------------------------------------------
353 Type: int array (min = 0, max = 32)
354 Syntax: <50|60[,...]>
355 Description: Light frequency in Hz:
356 50 for European and Asian lighting, 60 for American lighting.
357 Default: 50 for every device.
358 -------------------------------------------------------------------------------
360 Type: bool array (min = 0, max = 32)
362 Description: Banding filter to reduce effects of fluorescent
364 0 disabled, 1 enabled.
365 This filter tries to reduce the pattern of horizontal
366 light/dark bands caused by some (usually fluorescent) lighting.
367 Default: 0 for every device.
368 -------------------------------------------------------------------------------
370 Type: int array (min = 0, max = 32)
372 Description: Force pixel clock divisor to a specific value (for experts):
373 n may vary from 0 to 127.
374 -1 for automatic value.
375 See also the 'double_buffer' module parameter.
376 Default: -1 for every device.
377 -------------------------------------------------------------------------------
379 Type: bool array (min = 0, max = 32)
381 Description: Objects are lit from behind:
383 Default: 0 for every device.
384 -------------------------------------------------------------------------------
386 Type: bool array (min = 0, max = 32)
388 Description: Reverse image horizontally:
390 Default: 0 for every device.
391 -------------------------------------------------------------------------------
393 Type: bool array (min = 0, max = 32)
395 Description: The image sensor is monochrome:
397 Default: 0 for every device.
398 -------------------------------------------------------------------------------
400 Type: long array (min = 0, max = 32)
402 Description: Set picture brightness (0-65535).
403 This parameter has no effect if 'autobright' is enabled.
404 Default: 31000 for every device.
405 -------------------------------------------------------------------------------
407 Type: long array (min = 0, max = 32)
409 Description: Set picture hue (0-65535).
410 Default: 32768 for every device.
411 -------------------------------------------------------------------------------
413 Type: long array (min = 0, max = 32)
415 Description: Set picture saturation (0-65535).
416 Default: 32768 for every device.
417 -------------------------------------------------------------------------------
419 Type: long array (min = 0, max = 32)
421 Description: Set picture contrast (0-65535).
422 Default: 50000 for every device.
423 -------------------------------------------------------------------------------
425 Type: long array (min = 0, max = 32)
427 Description: Set picture whiteness (0-65535).
428 Default: 32768 for every device.
429 -------------------------------------------------------------------------------
433 Description: Debugging information level, from 0 to 6:
434 0 = none (use carefully)
436 2 = significant informations
437 3 = configuration or general messages
440 6 = function internals
441 Level 5 and 6 are useful for testing only, when only one
444 -------------------------------------------------------------------------------
448 Description: Enable or disable specific debugging messages:
449 0 = print messages concerning every level <= 'debug' level.
450 1 = print messages concerning the level indicated by 'debug'.
452 -------------------------------------------------------------------------------
455 8. Contact information
456 ======================
457 I may be contacted by e-mail at <luca.risolia@studio.unibo.it>.
459 I can accept GPG/PGP encrypted e-mail. My GPG key ID is 'FCE635A4'.
460 My public 1024-bit key should be available at your keyserver; the fingerprint
461 is: '88E8 F32F 7244 68BA 3958 5D40 99DA 5D2A FCE6 35A4'.
466 The development would not have proceed much further without having looked at
467 the source code of other drivers and without the help of several persons; in
470 - the I2C interface to kernel and high-level image sensor control routines have
471 been taken from the OV511 driver by Mark McClelland;
473 - memory management code has been copied from the bttv driver by Ralph Metzler,
474 Marcus Metzler and Gerd Knorr;
476 - the low-level I2C read function has been written by Frederic Jouault;
478 - the low-level I2C fast write function has been written by Piotr Czerczak.