diff options
Diffstat (limited to 'Documentation/media/uapi/v4l/diff-v4l.rst')
-rw-r--r-- | Documentation/media/uapi/v4l/diff-v4l.rst | 676 |
1 files changed, 203 insertions, 473 deletions
diff --git a/Documentation/media/uapi/v4l/diff-v4l.rst b/Documentation/media/uapi/v4l/diff-v4l.rst index 0419e2051759..76b2ecab8657 100644 --- a/Documentation/media/uapi/v4l/diff-v4l.rst +++ b/Documentation/media/uapi/v4l/diff-v4l.rst @@ -39,39 +39,19 @@ using driver module options. The major device number remains 81. :header-rows: 1 :stub-columns: 0 - - - .. row 1 - - - Device Type - - - File Name - - - Minor Numbers - - - .. row 2 - - - Video capture and overlay - - - ``/dev/video`` and ``/dev/bttv0``\ [#f1]_, ``/dev/video0`` to - ``/dev/video63`` - - - 0-63 - - - .. row 3 - - - Radio receiver - - - ``/dev/radio``\ [#f2]_, ``/dev/radio0`` to ``/dev/radio63`` - - - 64-127 - - - .. row 4 - - - Raw VBI capture - - - ``/dev/vbi``, ``/dev/vbi0`` to ``/dev/vbi31`` - - - 224-255 + * - Device Type + - File Name + - Minor Numbers + * - Video capture and overlay + - ``/dev/video`` and ``/dev/bttv0``\ [#f1]_, ``/dev/video0`` to + ``/dev/video63`` + - 0-63 + * - Radio receiver + - ``/dev/radio``\ [#f2]_, ``/dev/radio0`` to ``/dev/radio63`` + - 64-127 + * - Raw VBI capture + - ``/dev/vbi``, ``/dev/vbi0`` to ``/dev/vbi31`` + - 224-255 V4L prohibits (or used to prohibit) multiple opens of a device file. @@ -103,148 +83,73 @@ introduction. :header-rows: 1 :stub-columns: 0 - - - .. row 1 - - - ``struct video_capability`` ``type`` - - - struct :c:type:`v4l2_capability` - ``capabilities`` flags - - - Purpose - - - .. row 2 - - - ``VID_TYPE_CAPTURE`` - - - ``V4L2_CAP_VIDEO_CAPTURE`` - - - The :ref:`video capture <capture>` interface is supported. - - - .. row 3 - - - ``VID_TYPE_TUNER`` - - - ``V4L2_CAP_TUNER`` - - - The device has a :ref:`tuner or modulator <tuner>`. - - - .. row 4 - - - ``VID_TYPE_TELETEXT`` - - - ``V4L2_CAP_VBI_CAPTURE`` - - - The :ref:`raw VBI capture <raw-vbi>` interface is supported. - - - .. row 5 - - - ``VID_TYPE_OVERLAY`` - - - ``V4L2_CAP_VIDEO_OVERLAY`` - - - The :ref:`video overlay <overlay>` interface is supported. - - - .. row 6 - - - ``VID_TYPE_CHROMAKEY`` - - - ``V4L2_FBUF_CAP_CHROMAKEY`` in field ``capability`` of struct - :c:type:`v4l2_framebuffer` - - - Whether chromakey overlay is supported. For more information on - overlay see :ref:`overlay`. - - - .. row 7 - - - ``VID_TYPE_CLIPPING`` - - - ``V4L2_FBUF_CAP_LIST_CLIPPING`` and - ``V4L2_FBUF_CAP_BITMAP_CLIPPING`` in field ``capability`` of - struct :c:type:`v4l2_framebuffer` - - - Whether clipping the overlaid image is supported, see - :ref:`overlay`. - - - .. row 8 - - - ``VID_TYPE_FRAMERAM`` - - - ``V4L2_FBUF_CAP_EXTERNOVERLAY`` *not set* in field ``capability`` - of struct :c:type:`v4l2_framebuffer` - - - Whether overlay overwrites frame buffer memory, see - :ref:`overlay`. - - - .. row 9 - - - ``VID_TYPE_SCALES`` - - - ``-`` - - - This flag indicates if the hardware can scale images. The V4L2 API - implies the scale factor by setting the cropping dimensions and - image size with the :ref:`VIDIOC_S_CROP <VIDIOC_G_CROP>` and - :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl, respectively. The - driver returns the closest sizes possible. For more information on - cropping and scaling see :ref:`crop`. - - - .. row 10 - - - ``VID_TYPE_MONOCHROME`` - - - ``-`` - - - Applications can enumerate the supported image formats with the - :ref:`VIDIOC_ENUM_FMT` ioctl to determine if - the device supports grey scale capturing only. For more - information on image formats see :ref:`pixfmt`. - - - .. row 11 - - - ``VID_TYPE_SUBCAPTURE`` - - - ``-`` - - - Applications can call the :ref:`VIDIOC_G_CROP <VIDIOC_G_CROP>` - ioctl to determine if the device supports capturing a subsection - of the full picture ("cropping" in V4L2). If not, the ioctl - returns the ``EINVAL`` error code. For more information on cropping - and scaling see :ref:`crop`. - - - .. row 12 - - - ``VID_TYPE_MPEG_DECODER`` - - - ``-`` - - - Applications can enumerate the supported image formats with the - :ref:`VIDIOC_ENUM_FMT` ioctl to determine if - the device supports MPEG streams. - - - .. row 13 - - - ``VID_TYPE_MPEG_ENCODER`` - - - ``-`` - - - See above. - - - .. row 14 - - - ``VID_TYPE_MJPEG_DECODER`` - - - ``-`` - - - See above. - - - .. row 15 - - - ``VID_TYPE_MJPEG_ENCODER`` - - - ``-`` - - - See above. + * - ``struct video_capability`` ``type`` + - struct :c:type:`v4l2_capability` + ``capabilities`` flags + - Purpose + * - ``VID_TYPE_CAPTURE`` + - ``V4L2_CAP_VIDEO_CAPTURE`` + - The :ref:`video capture <capture>` interface is supported. + * - ``VID_TYPE_TUNER`` + - ``V4L2_CAP_TUNER`` + - The device has a :ref:`tuner or modulator <tuner>`. + * - ``VID_TYPE_TELETEXT`` + - ``V4L2_CAP_VBI_CAPTURE`` + - The :ref:`raw VBI capture <raw-vbi>` interface is supported. + * - ``VID_TYPE_OVERLAY`` + - ``V4L2_CAP_VIDEO_OVERLAY`` + - The :ref:`video overlay <overlay>` interface is supported. + * - ``VID_TYPE_CHROMAKEY`` + - ``V4L2_FBUF_CAP_CHROMAKEY`` in field ``capability`` of struct + :c:type:`v4l2_framebuffer` + - Whether chromakey overlay is supported. For more information on + overlay see :ref:`overlay`. + * - ``VID_TYPE_CLIPPING`` + - ``V4L2_FBUF_CAP_LIST_CLIPPING`` and + ``V4L2_FBUF_CAP_BITMAP_CLIPPING`` in field ``capability`` of + struct :c:type:`v4l2_framebuffer` + - Whether clipping the overlaid image is supported, see + :ref:`overlay`. + * - ``VID_TYPE_FRAMERAM`` + - ``V4L2_FBUF_CAP_EXTERNOVERLAY`` *not set* in field ``capability`` + of struct :c:type:`v4l2_framebuffer` + - Whether overlay overwrites frame buffer memory, see + :ref:`overlay`. + * - ``VID_TYPE_SCALES`` + - ``-`` + - This flag indicates if the hardware can scale images. The V4L2 API + implies the scale factor by setting the cropping dimensions and + image size with the :ref:`VIDIOC_S_CROP <VIDIOC_G_CROP>` and + :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl, respectively. The + driver returns the closest sizes possible. For more information on + cropping and scaling see :ref:`crop`. + * - ``VID_TYPE_MONOCHROME`` + - ``-`` + - Applications can enumerate the supported image formats with the + :ref:`VIDIOC_ENUM_FMT` ioctl to determine if + the device supports grey scale capturing only. For more + information on image formats see :ref:`pixfmt`. + * - ``VID_TYPE_SUBCAPTURE`` + - ``-`` + - Applications can call the :ref:`VIDIOC_G_CROP <VIDIOC_G_CROP>` + ioctl to determine if the device supports capturing a subsection + of the full picture ("cropping" in V4L2). If not, the ioctl + returns the ``EINVAL`` error code. For more information on cropping + and scaling see :ref:`crop`. + * - ``VID_TYPE_MPEG_DECODER`` + - ``-`` + - Applications can enumerate the supported image formats with the + :ref:`VIDIOC_ENUM_FMT` ioctl to determine if + the device supports MPEG streams. + * - ``VID_TYPE_MPEG_ENCODER`` + - ``-`` + - See above. + * - ``VID_TYPE_MJPEG_DECODER`` + - ``-`` + - See above. + * - ``VID_TYPE_MJPEG_ENCODER`` + - ``-`` + - See above. The ``audios`` field was replaced by ``capabilities`` flag @@ -280,24 +185,12 @@ video input types were renamed as follows: :header-rows: 1 :stub-columns: 0 - - - .. row 1 - - - struct ``video_channel`` ``type`` - - - struct :c:type:`v4l2_input` ``type`` - - - .. row 2 - - - ``VIDEO_TYPE_TV`` - - - ``V4L2_INPUT_TYPE_TUNER`` - - - .. row 3 - - - ``VIDEO_TYPE_CAMERA`` - - - ``V4L2_INPUT_TYPE_CAMERA`` + * - struct ``video_channel`` ``type`` + - struct :c:type:`v4l2_input` ``type`` + * - ``VIDEO_TYPE_TV`` + - ``V4L2_INPUT_TYPE_TUNER`` + * - ``VIDEO_TYPE_CAMERA`` + - ``V4L2_INPUT_TYPE_CAMERA`` Unlike the ``tuners`` field expressing the number of tuners of this @@ -386,42 +279,18 @@ replaced by V4L2 controls accessible with the :header-rows: 1 :stub-columns: 0 - - - .. row 1 - - - struct ``video_picture`` - - - V4L2 Control ID - - - .. row 2 - - - ``brightness`` - - - ``V4L2_CID_BRIGHTNESS`` - - - .. row 3 - - - ``hue`` - - - ``V4L2_CID_HUE`` - - - .. row 4 - - - ``colour`` - - - ``V4L2_CID_SATURATION`` - - - .. row 5 - - - ``contrast`` - - - ``V4L2_CID_CONTRAST`` - - - .. row 6 - - - ``whiteness`` - - - ``V4L2_CID_WHITENESS`` + * - struct ``video_picture`` + - V4L2 Control ID + * - ``brightness`` + - ``V4L2_CID_BRIGHTNESS`` + * - ``hue`` + - ``V4L2_CID_HUE`` + * - ``colour`` + - ``V4L2_CID_SATURATION`` + * - ``contrast`` + - ``V4L2_CID_CONTRAST`` + * - ``whiteness`` + - ``V4L2_CID_WHITENESS`` The V4L picture controls are assumed to range from 0 to 65535 with no @@ -442,108 +311,40 @@ into the struct :c:type:`v4l2_pix_format`: :header-rows: 1 :stub-columns: 0 - - - .. row 1 - - - struct ``video_picture`` ``palette`` - - - struct :c:type:`v4l2_pix_format` ``pixfmt`` - - - .. row 2 - - - ``VIDEO_PALETTE_GREY`` - - - :ref:`V4L2_PIX_FMT_GREY <V4L2-PIX-FMT-GREY>` - - - .. row 3 - - - ``VIDEO_PALETTE_HI240`` - - - :ref:`V4L2_PIX_FMT_HI240 <pixfmt-reserved>` [#f3]_ - - - .. row 4 - - - ``VIDEO_PALETTE_RGB565`` - - - :ref:`V4L2_PIX_FMT_RGB565 <pixfmt-rgb>` - - - .. row 5 - - - ``VIDEO_PALETTE_RGB555`` - - - :ref:`V4L2_PIX_FMT_RGB555 <pixfmt-rgb>` - - - .. row 6 - - - ``VIDEO_PALETTE_RGB24`` - - - :ref:`V4L2_PIX_FMT_BGR24 <pixfmt-rgb>` - - - .. row 7 - - - ``VIDEO_PALETTE_RGB32`` - - - :ref:`V4L2_PIX_FMT_BGR32 <pixfmt-rgb>` [#f4]_ - - - .. row 8 - - - ``VIDEO_PALETTE_YUV422`` - - - :ref:`V4L2_PIX_FMT_YUYV <V4L2-PIX-FMT-YUYV>` - - - .. row 9 - - - ``VIDEO_PALETTE_YUYV``\ [#f5]_ - - - :ref:`V4L2_PIX_FMT_YUYV <V4L2-PIX-FMT-YUYV>` - - - .. row 10 - - - ``VIDEO_PALETTE_UYVY`` - - - :ref:`V4L2_PIX_FMT_UYVY <V4L2-PIX-FMT-UYVY>` - - - .. row 11 - - - ``VIDEO_PALETTE_YUV420`` - - - None - - - .. row 12 - - - ``VIDEO_PALETTE_YUV411`` - - - :ref:`V4L2_PIX_FMT_Y41P <V4L2-PIX-FMT-Y41P>` [#f6]_ - - - .. row 13 - - - ``VIDEO_PALETTE_RAW`` - - - None [#f7]_ - - - .. row 14 - - - ``VIDEO_PALETTE_YUV422P`` - - - :ref:`V4L2_PIX_FMT_YUV422P <V4L2-PIX-FMT-YUV422P>` - - - .. row 15 - - - ``VIDEO_PALETTE_YUV411P`` - - - :ref:`V4L2_PIX_FMT_YUV411P <V4L2-PIX-FMT-YUV411P>` [#f8]_ - - - .. row 16 - - - ``VIDEO_PALETTE_YUV420P`` - - - :ref:`V4L2_PIX_FMT_YVU420 <V4L2-PIX-FMT-YVU420>` - - - .. row 17 - - - ``VIDEO_PALETTE_YUV410P`` - - - :ref:`V4L2_PIX_FMT_YVU410 <V4L2-PIX-FMT-YVU410>` + * - struct ``video_picture`` ``palette`` + - struct :c:type:`v4l2_pix_format` ``pixfmt`` + * - ``VIDEO_PALETTE_GREY`` + - :ref:`V4L2_PIX_FMT_GREY <V4L2-PIX-FMT-GREY>` + * - ``VIDEO_PALETTE_HI240`` + - :ref:`V4L2_PIX_FMT_HI240 <pixfmt-reserved>` [#f3]_ + * - ``VIDEO_PALETTE_RGB565`` + - :ref:`V4L2_PIX_FMT_RGB565 <pixfmt-rgb>` + * - ``VIDEO_PALETTE_RGB555`` + - :ref:`V4L2_PIX_FMT_RGB555 <pixfmt-rgb>` + * - ``VIDEO_PALETTE_RGB24`` + - :ref:`V4L2_PIX_FMT_BGR24 <pixfmt-rgb>` + * - ``VIDEO_PALETTE_RGB32`` + - :ref:`V4L2_PIX_FMT_BGR32 <pixfmt-rgb>` [#f4]_ + * - ``VIDEO_PALETTE_YUV422`` + - :ref:`V4L2_PIX_FMT_YUYV <V4L2-PIX-FMT-YUYV>` + * - ``VIDEO_PALETTE_YUYV``\ [#f5]_ + - :ref:`V4L2_PIX_FMT_YUYV <V4L2-PIX-FMT-YUYV>` + * - ``VIDEO_PALETTE_UYVY`` + - :ref:`V4L2_PIX_FMT_UYVY <V4L2-PIX-FMT-UYVY>` + * - ``VIDEO_PALETTE_YUV420`` + - None + * - ``VIDEO_PALETTE_YUV411`` + - :ref:`V4L2_PIX_FMT_Y41P <V4L2-PIX-FMT-Y41P>` [#f6]_ + * - ``VIDEO_PALETTE_RAW`` + - None [#f7]_ + * - ``VIDEO_PALETTE_YUV422P`` + - :ref:`V4L2_PIX_FMT_YUV422P <V4L2-PIX-FMT-YUV422P>` + * - ``VIDEO_PALETTE_YUV411P`` + - :ref:`V4L2_PIX_FMT_YUV411P <V4L2-PIX-FMT-YUV411P>` [#f8]_ + * - ``VIDEO_PALETTE_YUV420P`` + - :ref:`V4L2_PIX_FMT_YVU420 <V4L2-PIX-FMT-YVU420>` + * - ``VIDEO_PALETTE_YUV410P`` + - :ref:`V4L2_PIX_FMT_YVU410 <V4L2-PIX-FMT-YVU410>` V4L2 image formats are defined in :ref:`pixfmt`. The image format can @@ -588,36 +389,16 @@ The following fields where replaced by V4L2 controls accessible with the :header-rows: 1 :stub-columns: 0 - - - .. row 1 - - - struct ``video_audio`` - - - V4L2 Control ID - - - .. row 2 - - - ``volume`` - - - ``V4L2_CID_AUDIO_VOLUME`` - - - .. row 3 - - - ``bass`` - - - ``V4L2_CID_AUDIO_BASS`` - - - .. row 4 - - - ``treble`` - - - ``V4L2_CID_AUDIO_TREBLE`` - - - .. row 5 - - - ``balance`` - - - ``V4L2_CID_AUDIO_BALANCE`` + * - struct ``video_audio`` + - V4L2 Control ID + * - ``volume`` + - ``V4L2_CID_AUDIO_VOLUME`` + * - ``bass`` + - ``V4L2_CID_AUDIO_BASS`` + * - ``treble`` + - ``V4L2_CID_AUDIO_TREBLE`` + * - ``balance`` + - ``V4L2_CID_AUDIO_BALANCE`` To determine which of these controls are supported by a driver V4L @@ -752,68 +533,49 @@ differences. :header-rows: 1 :stub-columns: 0 - - - .. row 1 - - - V4L - - - V4L2 - - - .. row 2 - - - - - The image format must be selected before buffers are allocated, - with the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl. When no - format is selected the driver may use the last, possibly by - another application requested format. - - - .. row 3 - - - Applications cannot change the number of buffers. The it is built - into the driver, unless it has a module option to change the - number when the driver module is loaded. - - - The :ref:`VIDIOC_REQBUFS` ioctl allocates the - desired number of buffers, this is a required step in the - initialization sequence. - - - .. row 4 - - - Drivers map all buffers as one contiguous range of memory. The - ``VIDIOCGMBUF`` ioctl is available to query the number of buffers, - the offset of each buffer from the start of the virtual file, and - the overall amount of memory used, which can be used as arguments - for the :ref:`mmap() <func-mmap>` function. - - - Buffers are individually mapped. The offset and size of each - buffer can be determined with the - :ref:`VIDIOC_QUERYBUF` ioctl. - - - .. row 5 - - - The ``VIDIOCMCAPTURE`` ioctl prepares a buffer for capturing. It - also determines the image format for this buffer. The ioctl - returns immediately, eventually with an ``EAGAIN`` error code if no - video signal had been detected. When the driver supports more than - one buffer applications can call the ioctl multiple times and thus - have multiple outstanding capture requests. - - The ``VIDIOCSYNC`` ioctl suspends execution until a particular - buffer has been filled. - - - Drivers maintain an incoming and outgoing queue. - :ref:`VIDIOC_QBUF` enqueues any empty buffer into - the incoming queue. Filled buffers are dequeued from the outgoing - queue with the :ref:`VIDIOC_DQBUF <VIDIOC_QBUF>` ioctl. To wait - until filled buffers become available this function, - :ref:`select() <func-select>` or :ref:`poll() <func-poll>` can - be used. The :ref:`VIDIOC_STREAMON` ioctl - must be called once after enqueuing one or more buffers to start - capturing. Its counterpart - :ref:`VIDIOC_STREAMOFF <VIDIOC_STREAMON>` stops capturing and - dequeues all buffers from both queues. Applications can query the - signal status, if known, with the - :ref:`VIDIOC_ENUMINPUT` ioctl. + * - V4L + - V4L2 + * - + - The image format must be selected before buffers are allocated, + with the :ref:`VIDIOC_S_FMT <VIDIOC_G_FMT>` ioctl. When no + format is selected the driver may use the last, possibly by + another application requested format. + * - Applications cannot change the number of buffers. The it is built + into the driver, unless it has a module option to change the + number when the driver module is loaded. + - The :ref:`VIDIOC_REQBUFS` ioctl allocates the + desired number of buffers, this is a required step in the + initialization sequence. + * - Drivers map all buffers as one contiguous range of memory. The + ``VIDIOCGMBUF`` ioctl is available to query the number of buffers, + the offset of each buffer from the start of the virtual file, and + the overall amount of memory used, which can be used as arguments + for the :ref:`mmap() <func-mmap>` function. + - Buffers are individually mapped. The offset and size of each + buffer can be determined with the + :ref:`VIDIOC_QUERYBUF` ioctl. + * - The ``VIDIOCMCAPTURE`` ioctl prepares a buffer for capturing. It + also determines the image format for this buffer. The ioctl + returns immediately, eventually with an ``EAGAIN`` error code if no + video signal had been detected. When the driver supports more than + one buffer applications can call the ioctl multiple times and thus + have multiple outstanding capture requests. + + The ``VIDIOCSYNC`` ioctl suspends execution until a particular + buffer has been filled. + - Drivers maintain an incoming and outgoing queue. + :ref:`VIDIOC_QBUF` enqueues any empty buffer into + the incoming queue. Filled buffers are dequeued from the outgoing + queue with the :ref:`VIDIOC_DQBUF <VIDIOC_QBUF>` ioctl. To wait + until filled buffers become available this function, + :ref:`select() <func-select>` or :ref:`poll() <func-poll>` can + be used. The :ref:`VIDIOC_STREAMON` ioctl + must be called once after enqueuing one or more buffers to start + capturing. Its counterpart + :ref:`VIDIOC_STREAMOFF <VIDIOC_STREAMON>` stops capturing and + dequeues all buffers from both queues. Applications can query the + signal status, if known, with the + :ref:`VIDIOC_ENUMINPUT` ioctl. For a more in-depth discussion of memory mapping and examples, see @@ -835,56 +597,24 @@ with the following parameters: :header-rows: 1 :stub-columns: 0 - - - .. row 1 - - - struct :c:type:`v4l2_vbi_format` - - - V4L, BTTV driver - - - .. row 2 - - - sampling_rate - - - 28636363 Hz NTSC (or any other 525-line standard); 35468950 Hz PAL - and SECAM (625-line standards) - - - .. row 3 - - - offset - - - ? - - - .. row 4 - - - samples_per_line - - - 2048 - - - .. row 5 - - - sample_format - - - V4L2_PIX_FMT_GREY. The last four bytes (a machine endianness - integer) contain a frame counter. - - - .. row 6 - - - start[] - - - 10, 273 NTSC; 22, 335 PAL and SECAM - - - .. row 7 - - - count[] - - - 16, 16 [#f9]_ - - - .. row 8 - - - flags - - - 0 + * - struct :c:type:`v4l2_vbi_format` + - V4L, BTTV driver + * - sampling_rate + - 28636363 Hz NTSC (or any other 525-line standard); 35468950 Hz PAL + and SECAM (625-line standards) + * - offset + - ? + * - samples_per_line + - 2048 + * - sample_format + - V4L2_PIX_FMT_GREY. The last four bytes (a machine endianness + integer) contain a frame counter. + * - start[] + - 10, 273 NTSC; 22, 335 PAL and SECAM + * - count[] + - 16, 16 [#f9]_ + * - flags + - 0 Undocumented in the V4L specification, in Linux 2.3 the |