1 -------------------------------------------------------------------------------
2 Readme for Linux device driver for the OmniVision OV511 USB to camera bridge IC
3 -------------------------------------------------------------------------------
5 Author: Mark McClelland
6 Homepage: http://alpha.dyndns.org/ov511
10 This is a preliminary version of my OV511 Linux device driver. Currently, it can
11 grab a frame in color (YUV420) at 640x480 or 320x240 using either vidcat or
12 xawtv. Other utilities may work but have not yet been tested.
15 o Preliminary snapshot support
16 o Experimental red-blue misalignment fixes
17 o Better YUV420 color conversion
19 o Finer-grained debug message control
20 o Support for new cameras (4, 36)
24 _________________________________________________________
25 Manufacturer | Model | Custom ID | Status
26 -----------------+-----------------+-----------+---------
27 MediaForte | MV300 | 0 | Working
28 Aiptek | HyperVCam ? | 0 | Working
29 NetView | NV300M | 0 | Working
30 D-Link | DSB-C300 | 3 | Working
31 Hawking Tech. | ??? | 3 | Working
32 ??? | Generic | 4 | Untested
33 Puretek | PT-6007 | 5 | Working
34 Creative Labs | WebCam 3 | 21 | Working
35 ??? | Koala-Cam | 36 | Untested
36 Lifeview | RoboCam | 100 | Untested
37 AverMedia | InterCam Elite | 102 | Working
38 MediaForte | MV300 | 112 | Working
39 Omnivision | OV7110 EV board | 112 | Working*
40 ---------------------------------------------------------
41 (*) uses OV7110 (monochrome)
43 Any camera using the OV511 and the OV7610 CCD should work with this driver. The
44 driver only detects known cameras though, based on their custom id number. If
45 you have a currently unsupported camera, the ID number should be reported to you
46 in the kernel logs. Please send me the model, manufacturer and ID number and I
47 will add it to the detection code. In the meantime, you can add to the code
48 yourself in the function ov511_probe().
52 - If you want to help with the development, get the chip's specification docs at
53 http://www.ovt.com/omniusbp.html
55 - A Video4Linux compatible frame grabber program (I recommend vidcat and xawtv)
56 vidcat is part of the w3cam package: http://www.hdk-berlin.de/~rasca/w3cam/
57 xawtv is available at: http://www.in-berlin.de/User/kraxel/xawtv.html
61 You must have first compiled USB support, support for your specific USB host
62 controller (UHCI or OHCI), and Video4Linux support for your kernel (I recommend
65 Next, (as root) from your appropriate modules directory (lib/modules/2.3.XX):
68 insmod usb/usb-uhci.o <OR> insmod usb/ohci-hcd.o
69 insmod misc/videodev.o
72 If it is not already there (it usually is), create the video device:
74 mknod /dev/video c 81 0
76 Sometimes /dev/video is a symlink to /dev/video0
78 You will have to set permissions on this device to allow you to read/write
82 chmod 666 /dev/video0 (if necessary)
84 Now you are ready to run a video app! Both vidcat and xawtv work well for me
89 vidcat -s 640x480 > test.jpg
94 You must make some modifications to the source and compile it before you use it.
95 (Note: this may not be applicable to versions other than 3.06)
97 In src/Xawtv.ad, change xawtv.tv.width to 640 and xawtv.tv.height to 480. Next,
98 in src/grab-v4l.c, change SYNC_TIMEOUT from 1 to 2. Then, from the main xawtv
106 Now you should be able to run xawtv. Right click for the options dialog. If
107 you get a scrambled image it is likely that you made a mistake in Xawtv.ad.
108 Try setting the size to 320x240 if all else fails.
111 Q: "Why does the picture have noise and look grainy"
112 A: This is a problem at low light levels, and may be also due to subtle bugs in
113 the code. The cause is most likely the OV7610 settings we are currently
114 using. I am looking into this problem.
116 Q: "The driver sometimes says `Failed to read OV7610 ID.' What is the deal?"
117 A: The I2C code that allows the OV511 to communicate with the camera chip is a
118 bit flaky right now. This message means that the I2C bus never got
119 initialized properly, and the camera will most likely not work even if you
120 disable this warning. Try unloading/reloading the driver or unplugging/re-
121 plugging the camera if this happens.
123 Q: "Why do you bother with this phony camera detection crap? It doesn't do
125 A: The main purpose of only supporting known camera models is to force people
126 with new camera models to tell me about them, so I can assemble the list
127 above, and so the code can know what CCD chip you have. Right now, nearly all
128 of the cameras use the OV7610 and consequently I have not put support for
129 other ones in, so the value of the detection code is questionable. Eventually
130 though, new CCDs might appear and we will be fortunate to have the detection.
134 You can set these with: insmod ov511 NAME=VALUE
135 There is currently no way to set these on a per-camera basis.
138 TYPE: integer (boolean)
140 DESC: The camera normally adjusts exposure, gain, and hue automatically. This
141 can be set to 0 to disable this automatic adjustment. Note that there is
142 currently no way to set these parameters manually once autoadjust is
143 disabled. (This feature is not working yet)
148 DESC: Sets the threshold for printing debug messages. The higher the value,
149 the more is printed. The levels are cumulative, and are as follows:
151 1=init/detection/unload and other significant messages
152 2=some warning messages
153 3=config/control function calls
154 4=most function calls and data parsing messages
155 5=highly repetitive mesgs
158 TYPE: integer (boolean)
160 DESC: Some people have reported that the blue component of the image is one
161 or so lines higher than the red component. This is only apparent in
162 images with white objects on black backgrounds at 640x480. Setting this
163 to 1 will realign the color planes correctly. NOTE: This is still
164 experimental and very buggy.
167 TYPE: integer (boolean)
169 DESC: Set to 1 to enable snapshot mode. read() will block until the snapshot
170 button is pressed. Note that this does not yet work with most apps,
171 including xawtv and vidcat. NOTE: See the section "TODO" for more info.
174 o Color streaming/capture at 640x480 and 320x240
177 o Setting/getting of saturation, contrast and brightness (no color yet)
179 EXPERIMENTAL FEATURES:
180 o fix_rgb_offset: Sometimes works, but other times causes errors with xawtv and
182 o Snapshot mode (only works with some read() based apps; see below for more)
185 o Fix the noise / grainy image problem.
186 o Get compression working. It would be a nice addition as it improves
187 frame rate quite a bit. OmniVision wouldn't tell me how the algorithm works,
188 so we can't really work on that yet. Please kindly inform OmniVision that you
189 would like them to release their specifications to the Linux community.
190 o Get 160x120 working
191 o YUV422 (and other color modes)
192 o Fix read(). It only works right now if you run an mmap() based app like xawtv
193 or vidcat after loading the module and before using read(). Apparently there
194 are some initialization issues.
195 o Get snapshot mode working with mmap().
196 o Fix fixFrameRGBoffset(). It is not stable yet with streaming video.
197 o Get hue (red/blue channel balance) adjustment working (in ov511_get_picture()
198 and ov511_set_picture())
199 o Get autoadjust disable working
200 o Devise some clean way to support different types of CCDs (based on Custom ID)
202 o V4L2 support (Probably not until it goes into the kernel)
203 o Fix I2C initialization. Some people are reporting problems with reading the
204 7610 registers. This could be due to timing differences, an excessive I2C
205 clock rate, or a problem with ov511_i2c_read().
206 o Get rid of the memory management functions (put them in videodev.c??)
210 You can email me at mmcclelland@delphi.com . Please prefix the subject line
211 with "OV511: " so that I am certain to notice your message.
215 The code is based in no small part on the CPiA driver by Johannes Erdfelt,
216 Randy Dunlap, and others. Big thanks to them for their pioneering work on that
217 and the USB stack. Thanks to Bret Wallach for getting camera reg IO , ISOC, and
218 image capture working. Thanks to Orion Sky Lawlor and Kevin Moore for their