LXR linux/Documentation/video4linux/meye.txt

   1Vaio Picturebook Motion Eye Camera Driver Readme
   2------------------------------------------------
   3        Copyright (C) 2001-2004 Stelian Pop <stelian@popies.net>
   4        Copyright (C) 2001-2002 Alcôve <www.alcove.com>
   5        Copyright (C) 2000 Andrew Tridgell <tridge@samba.org>
   6
   7This driver enable the use of video4linux compatible applications with the
   8Motion Eye camera. This driver requires the "Sony Laptop Extras" driver (which
   9can be found in the "Misc devices" section of the kernel configuration utility)
  10to be compiled and installed (using its "camera=1" parameter).
  11
  12It can do at maximum 30 fps @ 320x240 or 15 fps @ 640x480.
  13
  14Grabbing is supported in packed YUV colorspace only.
  15
  16MJPEG hardware grabbing is supported via a private API (see below).
  17
  18Hardware supported:
  19-------------------
  20
  21This driver supports the 'second' version of the MotionEye camera :)
  22
  23The first version was connected directly on the video bus of the Neomagic
  24video card and is unsupported.
  25
  26The second one, made by Kawasaki Steel is fully supported by this
  27driver (PCI vendor/device is 0x136b/0xff01)
  28
  29The third one, present in recent (more or less last year) Picturebooks
  30(C1M* models), is not supported. The manufacturer has given the specs
  31to the developers under a NDA (which allows the development of a GPL
  32driver however), but things are not moving very fast (see
  33http://r-engine.sourceforge.net/) (PCI vendor/device is 0x10cf/0x2011).
  34
  35There is a forth model connected on the USB bus in TR1* Vaio laptops.
  36This camera is not supported at all by the current driver, in fact
  37little information if any is available for this camera
  38(USB vendor/device is 0x054c/0x0107).
  39
  40Driver options:
  41---------------
  42
  43Several options can be passed to the meye driver using the standard
  44module argument syntax (<param>=<value> when passing the option to the
  45module or meye.<param>=<value> on the kernel boot line when meye is
  46statically linked into the kernel). Those options are:
  47
  48        forcev4l1:      force use of V4L1 API instead of V4L2
  49
  50        gbuffers:       number of capture buffers, default is 2 (32 max)
  51
  52        gbufsize:       size of each capture buffer, default is 614400
  53
  54        video_nr:       video device to register (0 = /dev/video0, etc)
  55
  56Module use:
  57-----------
  58
  59In order to automatically load the meye module on use, you can put those lines
  60in your /etc/modprobe.conf file:
  61
  62        alias char-major-81 videodev
  63        alias char-major-81-0 meye
  64        options meye gbuffers=32
  65
  66Usage:
  67------
  68
  69        xawtv >= 3.49 (<http://bytesex.org/xawtv/>)
  70                for display and uncompressed video capture:
  71
  72                        xawtv -c /dev/video0 -geometry 640x480
  73                                or
  74                        xawtv -c /dev/video0 -geometry 320x240
  75
  76        motioneye (<http://popies.net/meye/>)
  77                for getting ppm or jpg snapshots, mjpeg video
  78
  79Private API:
  80------------
  81
  82        The driver supports frame grabbing with the video4linux API
  83        (either v4l1 or v4l2), so all video4linux tools (like xawtv)
  84        should work with this driver.
  85
  86        Besides the video4linux interface, the driver has a private interface
  87        for accessing the Motion Eye extended parameters (camera sharpness,
  88        agc, video framerate), the shapshot and the MJPEG capture facilities.
  89
  90        This interface consists of several ioctls (prototypes and structures
  91        can be found in include/linux/meye.h):
  92
  93        MEYEIOC_G_PARAMS
  94        MEYEIOC_S_PARAMS
  95                Get and set the extended parameters of the motion eye camera.
  96                The user should always query the current parameters with
  97                MEYEIOC_G_PARAMS, change what he likes and then issue the
  98                MEYEIOC_S_PARAMS call (checking for -EINVAL). The extended
  99                parameters are described by the meye_params structure.
 100
 101
 102        MEYEIOC_QBUF_CAPT
 103                Queue a buffer for capture (the buffers must have been
 104                obtained with a VIDIOCGMBUF call and mmap'ed by the
 105                application). The argument to MEYEIOC_QBUF_CAPT is the
 106                buffer number to queue (or -1 to end capture). The first
 107                call to MEYEIOC_QBUF_CAPT starts the streaming capture.
 108
 109        MEYEIOC_SYNC
 110                Takes as an argument the buffer number you want to sync.
 111                This ioctl blocks until the buffer is filled and ready
 112                for the application to use. It returns the buffer size.
 113
 114        MEYEIOC_STILLCAPT
 115        MEYEIOC_STILLJCAPT
 116                Takes a snapshot in an uncompressed or compressed jpeg format.
 117                This ioctl blocks until the snapshot is done and returns (for
 118                jpeg snapshot) the size of the image. The image data is
 119                available from the first mmap'ed buffer.
 120
 121        Look at the 'motioneye' application code for an actual example.
 122
 123Bugs / Todo:
 124------------
 125
 126        - the driver could be much cleaned up by removing the v4l1 support.
 127          However, this means all v4l1-only applications will stop working.
 128
 129        - 'motioneye' still uses the meye private v4l1 API extensions.
 130