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author | Mauro Carvalho Chehab <mchehab@s-opensource.com> | 2017-04-17 02:51:08 +0200 |
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committer | Jonathan Corbet <corbet@lwn.net> | 2017-04-20 23:31:07 +0200 |
commit | 9b06f754133c6b22c9753586c3c2708bc509ff64 (patch) | |
tree | 30350a7191e4878dd17566741a4ca3d826b05ebb /drivers/media/usb/pwc | |
parent | docs-rst: usb: update old usbfs-related documentation (diff) | |
download | linux-9b06f754133c6b22c9753586c3c2708bc509ff64.tar.xz linux-9b06f754133c6b22c9753586c3c2708bc509ff64.zip |
convert philips.txt to ReST and add to media docs
The philips.txt file were at the wrong place: it should be,
instead, at Documentation/media.
Move and convert it.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Diffstat (limited to 'drivers/media/usb/pwc')
-rw-r--r-- | drivers/media/usb/pwc/philips.txt | 236 |
1 files changed, 0 insertions, 236 deletions
diff --git a/drivers/media/usb/pwc/philips.txt b/drivers/media/usb/pwc/philips.txt deleted file mode 100644 index d38dd791511e..000000000000 --- a/drivers/media/usb/pwc/philips.txt +++ /dev/null @@ -1,236 +0,0 @@ -This file contains some additional information for the Philips and OEM webcams. -E-mail: webcam@smcc.demon.nl Last updated: 2004-01-19 -Site: http://www.smcc.demon.nl/webcam/ - -As of this moment, the following cameras are supported: - * Philips PCA645 - * Philips PCA646 - * Philips PCVC675 - * Philips PCVC680 - * Philips PCVC690 - * Philips PCVC720/40 - * Philips PCVC730 - * Philips PCVC740 - * Philips PCVC750 - * Askey VC010 - * Creative Labs Webcam 5 - * Creative Labs Webcam Pro Ex - * Logitech QuickCam 3000 Pro - * Logitech QuickCam 4000 Pro - * Logitech QuickCam Notebook Pro - * Logitech QuickCam Zoom - * Logitech QuickCam Orbit - * Logitech QuickCam Sphere - * Samsung MPC-C10 - * Samsung MPC-C30 - * Sotec Afina Eye - * AME CU-001 - * Visionite VCS-UM100 - * Visionite VCS-UC300 - -The main webpage for the Philips driver is at the address above. It contains -a lot of extra information, a FAQ, and the binary plugin 'PWCX'. This plugin -contains decompression routines that allow you to use higher image sizes and -framerates; in addition the webcam uses less bandwidth on the USB bus (handy -if you want to run more than 1 camera simultaneously). These routines fall -under a NDA, and may therefore not be distributed as source; however, its use -is completely optional. - -You can build this code either into your kernel, or as a module. I recommend -the latter, since it makes troubleshooting a lot easier. The built-in -microphone is supported through the USB Audio class. - -When you load the module you can set some default settings for the -camera; some programs depend on a particular image-size or -format and -don't know how to set it properly in the driver. The options are: - -size - Can be one of 'sqcif', 'qsif', 'qcif', 'sif', 'cif' or - 'vga', for an image size of resp. 128x96, 160x120, 176x144, - 320x240, 352x288 and 640x480 (of course, only for those cameras that - support these resolutions). - -fps - Specifies the desired framerate. Is an integer in the range of 4-30. - -fbufs - This parameter specifies the number of internal buffers to use for storing - frames from the cam. This will help if the process that reads images from - the cam is a bit slow or momentarily busy. However, on slow machines it - only introduces lag, so choose carefully. The default is 3, which is - reasonable. You can set it between 2 and 5. - -mbufs - This is an integer between 1 and 10. It will tell the module the number of - buffers to reserve for mmap(), VIDIOCCGMBUF, VIDIOCMCAPTURE and friends. - The default is 2, which is adequate for most applications (double - buffering). - - Should you experience a lot of 'Dumping frame...' messages during - grabbing with a tool that uses mmap(), you might want to increase if. - However, it doesn't really buffer images, it just gives you a bit more - slack when your program is behind. But you need a multi-threaded or - forked program to really take advantage of these buffers. - - The absolute maximum is 10, but don't set it too high! Every buffer takes - up 460 KB of RAM, so unless you have a lot of memory setting this to - something more than 4 is an absolute waste. This memory is only - allocated during open(), so nothing is wasted when the camera is not in - use. - -power_save - When power_save is enabled (set to 1), the module will try to shut down - the cam on close() and re-activate on open(). This will save power and - turn off the LED. Not all cameras support this though (the 645 and 646 - don't have power saving at all), and some models don't work either (they - will shut down, but never wake up). Consider this experimental. By - default this option is disabled. - -compression (only useful with the plugin) - With this option you can control the compression factor that the camera - uses to squeeze the image through the USB bus. You can set the - parameter between 0 and 3: - 0 = prefer uncompressed images; if the requested mode is not available - in an uncompressed format, the driver will silently switch to low - compression. - 1 = low compression. - 2 = medium compression. - 3 = high compression. - - High compression takes less bandwidth of course, but it could also - introduce some unwanted artefacts. The default is 2, medium compression. - See the FAQ on the website for an overview of which modes require - compression. - - The compression parameter does not apply to the 645 and 646 cameras - and OEM models derived from those (only a few). Most cams honour this - parameter. - -leds - This settings takes 2 integers, that define the on/off time for the LED - (in milliseconds). One of the interesting things that you can do with - this is let the LED blink while the camera is in use. This: - - leds=500,500 - - will blink the LED once every second. But with: - - leds=0,0 - - the LED never goes on, making it suitable for silent surveillance. - - By default the camera's LED is on solid while in use, and turned off - when the camera is not used anymore. - - This parameter works only with the ToUCam range of cameras (720, 730, 740, - 750) and OEMs. For other cameras this command is silently ignored, and - the LED cannot be controlled. - - Finally: this parameters does not take effect UNTIL the first time you - open the camera device. Until then, the LED remains on. - -dev_hint - A long standing problem with USB devices is their dynamic nature: you - never know what device a camera gets assigned; it depends on module load - order, the hub configuration, the order in which devices are plugged in, - and the phase of the moon (i.e. it can be random). With this option you - can give the driver a hint as to what video device node (/dev/videoX) it - should use with a specific camera. This is also handy if you have two - cameras of the same model. - - A camera is specified by its type (the number from the camera model, - like PCA645, PCVC750VC, etc) and optionally the serial number (visible - in /proc/bus/usb/devices). A hint consists of a string with the following - format: - - [type[.serialnumber]:]node - - The square brackets mean that both the type and the serialnumber are - optional, but a serialnumber cannot be specified without a type (which - would be rather pointless). The serialnumber is separated from the type - by a '.'; the node number by a ':'. - - This somewhat cryptic syntax is best explained by a few examples: - - dev_hint=3,5 The first detected cam gets assigned - /dev/video3, the second /dev/video5. Any - other cameras will get the first free - available slot (see below). - - dev_hint=645:1,680:2 The PCA645 camera will get /dev/video1, - and a PCVC680 /dev/video2. - - dev_hint=645.0123:3,645.4567:0 The PCA645 camera with serialnumber - 0123 goes to /dev/video3, the same - camera model with the 4567 serial - gets /dev/video0. - - dev_hint=750:1,4,5,6 The PCVC750 camera will get /dev/video1, the - next 3 Philips cams will use /dev/video4 - through /dev/video6. - - Some points worth knowing: - - Serialnumbers are case sensitive and must be written full, including - leading zeroes (it's treated as a string). - - If a device node is already occupied, registration will fail and - the webcam is not available. - - You can have up to 64 video devices; be sure to make enough device - nodes in /dev if you want to spread the numbers. - After /dev/video9 comes /dev/video10 (not /dev/videoA). - - If a camera does not match any dev_hint, it will simply get assigned - the first available device node, just as it used to be. - -trace - In order to better detect problems, it is now possible to turn on a - 'trace' of some of the calls the module makes; it logs all items in your - kernel log at debug level. - - The trace variable is a bitmask; each bit represents a certain feature. - If you want to trace something, look up the bit value(s) in the table - below, add the values together and supply that to the trace variable. - - Value Value Description Default - (dec) (hex) - 1 0x1 Module initialization; this will log messages On - while loading and unloading the module - - 2 0x2 probe() and disconnect() traces On - - 4 0x4 Trace open() and close() calls Off - - 8 0x8 read(), mmap() and associated ioctl() calls Off - - 16 0x10 Memory allocation of buffers, etc. Off - - 32 0x20 Showing underflow, overflow and Dumping frame On - messages - - 64 0x40 Show viewport and image sizes Off - - 128 0x80 PWCX debugging Off - - For example, to trace the open() & read() functions, sum 8 + 4 = 12, - so you would supply trace=12 during insmod or modprobe. If - you want to turn the initialization and probing tracing off, set trace=0. - The default value for trace is 35 (0x23). - - - -Example: - - # modprobe pwc size=cif fps=15 power_save=1 - -The fbufs, mbufs and trace parameters are global and apply to all connected -cameras. Each camera has its own set of buffers. - -size and fps only specify defaults when you open() the device; this is to -accommodate some tools that don't set the size. You can change these -settings after open() with the Video4Linux ioctl() calls. The default of -defaults is QCIF size at 10 fps. - -The compression parameter is semiglobal; it sets the initial compression -preference for all camera's, but this parameter can be set per camera with -the VIDIOCPWCSCQUAL ioctl() call. - -All parameters are optional. - |