diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /Documentation/video4linux/README.cpia |
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/README.cpia')
-rw-r--r-- | Documentation/video4linux/README.cpia | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/Documentation/video4linux/README.cpia b/Documentation/video4linux/README.cpia new file mode 100644 index 00000000000..c95e7bbc0fd --- /dev/null +++ b/Documentation/video4linux/README.cpia @@ -0,0 +1,191 @@ +This is a driver for the CPiA PPC2 driven parallel connected +Camera. For example the Creative WebcamII is CPiA driven. + + ) [1]Peter Pregler, Linz 2000, published under the [2]GNU GPL + +--------------------------------------------------------------------------- + +USAGE: + +General: +======== + +1) Make sure you have created the video devices (/dev/video*): + +- if you have a recent MAKEDEV do a 'cd /dev;./MAKEDEV video' +- otherwise do a: + +cd /dev +mknod video0 c 81 0 +ln -s video0 video + +2) Compile the kernel (see below for the list of options to use), + configure your parport and reboot. + +3) If all worked well you should get messages similar + to the following (your versions may be different) on the console: + +V4L-Driver for Vision CPiA based cameras v0.7.4 +parport0: read2 timeout. +parport0: Multimedia device, VLSI Vision Ltd PPC2 +Parallel port driver for Vision CPiA based camera + CPIA Version: 1.20 (2.0) + CPIA PnP-ID: 0553:0002:0100 + VP-Version: 1.0 0100 + 1 camera(s) found + + +As modules: +=========== + +Make sure you have selected the following kernel options (you can +select all stuff as modules): + +The cpia-stuff is in the section 'Character devices -> Video For Linux'. + +CONFIG_PARPORT=m +CONFIG_PARPORT_PC=m +CONFIG_PARPORT_PC_FIFO=y +CONFIG_PARPORT_1284=y +CONFIG_VIDEO_DEV=m +CONFIG_VIDEO_CPIA=m +CONFIG_VIDEO_CPIA_PP=m + +For autoloading of all those modules you need to tell module-init-tools +some stuff. Add the following line to your module-init-tools config-file +(e.g. /etc/modprobe.conf or wherever your distribution does store that +stuff): + +options parport_pc io=0x378 irq=7 dma=3 +alias char-major-81 cpia_pp + +The first line tells the dma/irq channels to use. Those _must_ match +the settings of your BIOS. Do NOT simply use the values above. See +Documentation/parport.txt for more information about this. The second +line associates the video-device file with the driver. Of cause you +can also load the modules once upon boot (usually done in /etc/modules). + +Linked into the kernel: +======================= + +Make sure you have selected the following kernel options. Note that +you cannot compile the parport-stuff as modules and the cpia-driver +statically (the other way round is okay though). + +The cpia-stuff is in the section 'Character devices -> Video For Linux'. + +CONFIG_PARPORT=y +CONFIG_PARPORT_PC=y +CONFIG_PARPORT_PC_FIFO=y +CONFIG_PARPORT_1284=y +CONFIG_VIDEO_DEV=y +CONFIG_VIDEO_CPIA=y +CONFIG_VIDEO_CPIA_PP=y + +To use DMA/irq you will need to tell the kernel upon boot time the +hardware configuration of the parport. You can give the boot-parameter +at the LILO-prompt or specify it in lilo.conf. I use the following +append-line in lilo.conf: + + append="parport=0x378,7,3" + +See Documentation/parport.txt for more information about the +configuration of the parport and the values given above. Do not simply +use the values given above. + +--------------------------------------------------------------------------- +FEATURES: + +- mmap/read v4l-interface (but no overlay) +- image formats: CIF/QCIF, SIF/QSIF, various others used by isabel; + note: all sizes except CIF/QCIF are implemented by clipping, i.e. + pixels are not uploaded from the camera +- palettes: VIDEO_PALETTE_GRAY, VIDEO_PALETTE_RGB565, VIDEO_PALETTE_RGB555, + VIDEO_PALETTE_RGB24, VIDEO_PALETTE_RGB32, VIDEO_PALETTE_YUYV, + VIDEO_PALETTE_UYVY, VIDEO_PALETTE_YUV422 +- state information (color balance, exposure, ...) is preserved between + device opens +- complete control over camera via proc-interface (_all_ camera settings are + supported), there is also a python-gtk application available for this [3] +- works under SMP (but the driver is completely serialized and synchronous) + so you get no benefit from SMP, but at least it does not crash your box +- might work for non-Intel architecture, let us know about this + +--------------------------------------------------------------------------- +TESTED APPLICATIONS: + +- a simple test application based on Xt is available at [3] +- another test-application based on gqcam-0.4 (uses GTK) +- gqcam-0.6 should work +- xawtv-3.x (also the webcam software) +- xawtv-2.46 +- w3cam (cgi-interface and vidcat, e.g. you may try out 'vidcat |xv + -maxpect -root -quit +noresetroot -rmode 5 -') +- vic, the MBONE video conferencing tool (version 2.8ucl4-1) +- isabel 3R4beta (barely working, but AFAICT all the problems are on + their side) +- camserv-0.40 + +See [3] for pointers to v4l-applications. + +--------------------------------------------------------------------------- +KNOWN PROBLEMS: + +- some applications do not handle the image format correctly, you will + see strange horizontal stripes instead of a nice picture -> make sure + your application does use a supported image size or queries the driver + for the actually used size (reason behind this: the camera cannot + provide any image format, so if size NxM is requested the driver will + use a format to the closest fitting N1xM1, the application should now + query for this granted size, most applications do not). +- all the todo ;) +- if there is not enough light and the picture is too dark try to + adjust the SetSensorFPS setting, automatic frame rate adjustment + has its price +- do not try out isabel 3R4beta (built 135), you will be disappointed + +--------------------------------------------------------------------------- +TODO: + +- multiple camera support (struct camera or something) - This should work, + but hasn't been tested yet. +- architecture independence? +- SMP-safe asynchronous mmap interface +- nibble mode for old parport interfaces +- streaming capture, this should give a performance gain + +--------------------------------------------------------------------------- +IMPLEMENTATION NOTES: + +The camera can act in two modes, streaming or grabbing. Right now a +polling grab-scheme is used. Maybe interrupt driven streaming will be +used for a asynchronous mmap interface in the next major release of the +driver. This might give a better frame rate. + +--------------------------------------------------------------------------- +THANKS (in no particular order): + +- Scott J. Bertin <sbertin@mindspring.com> for cleanups, the proc-filesystem + and much more +- Henry Bruce <whb@vvl.co.uk> for providing developers information about + the CPiA chip, I wish all companies would treat Linux as seriously +- Karoly Erdei <Karoly.Erdei@risc.uni-linz.ac.at> and RISC-Linz for being + my boss ;) resp. my employer and for providing me the hardware and + allow me to devote some working time to this project +- Manuel J. Petit de Gabriel <mpetit@dit.upm.es> for providing help + with Isabel (http://isabel.dit.upm.es/) +- Bas Huisman <bhuism@cs.utwente.nl> for writing the initial parport code +- Jarl Totland <Jarl.Totland@bdc.no> for setting up the mailing list + and maintaining the web-server[3] +- Chris Whiteford <Chris@informinteractive.com> for fixes related to the + 1.02 firmware +- special kudos to all the tester whose machines crashed and/or + will crash. :) + +--------------------------------------------------------------------------- +REFERENCES + + 1. http://www.risc.uni-linz.ac.at/people/ppregler + mailto:Peter_Pregler@email.com + 2. see the file COPYING in the top directory of the kernel tree + 3. http://webcam.sourceforge.net/ |