diff options
Diffstat (limited to 'Documentation/userspace-api/media/dvb/legacy_dvb_video.rst')
| -rw-r--r-- | Documentation/userspace-api/media/dvb/legacy_dvb_video.rst | 2430 |
1 files changed, 2430 insertions, 0 deletions
diff --git a/Documentation/userspace-api/media/dvb/legacy_dvb_video.rst b/Documentation/userspace-api/media/dvb/legacy_dvb_video.rst new file mode 100644 index 0000000000..b9fd5cadae --- /dev/null +++ b/Documentation/userspace-api/media/dvb/legacy_dvb_video.rst @@ -0,0 +1,2430 @@ +.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later OR GPL-2.0 + +.. c:namespace:: dtv.legacy.video + +.. _dvb_video: + +================ +DVB Video Device +================ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +The DVB video device controls the MPEG2 video decoder of the DVB +hardware. It can be accessed through ``/dev/dvb/adapter0/video0``. Data +types and ioctl definitions can be accessed by including +``linux/dvb/video.h`` in your application. + +Note that the DVB video device only controls decoding of the MPEG video +stream, not its presentation on the TV or computer screen. On PCs this +is typically handled by an associated video4linux device, e.g. +``/dev/video``, which allows scaling and defining output windows. + +Most DVB cards don’t have their own MPEG decoder, which results in the +omission of the audio and video device as well as the video4linux +device. + +These ioctls were also used by V4L2 to control MPEG decoders implemented +in V4L2. The use of these ioctls for that purpose has been made obsolete +and proper V4L2 ioctls or controls have been created to replace that +functionality. Use :ref:`V4L2 ioctls<video>` for new drivers! + + +Video Data Types +================ + + + +video_format_t +-------------- + +Synopsis +~~~~~~~~ + +.. code-block:: c + + typedef enum { + VIDEO_FORMAT_4_3, + VIDEO_FORMAT_16_9, + VIDEO_FORMAT_221_1 + } video_format_t; + +Constants +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``VIDEO_FORMAT_4_3`` + + - Select 4:3 format. + + - .. + + - ``VIDEO_FORMAT_16_9`` + + - Select 16:9 format. + + - .. + + - ``VIDEO_FORMAT_221_1`` + + - Select 2.21:1 format. + +Description +~~~~~~~~~~~ + +The ``video_format_t`` data type +is used in the `VIDEO_SET_FORMAT`_ function to tell the driver which +aspect ratio the output hardware (e.g. TV) has. It is also used in the +data structures `video_status`_ returned by `VIDEO_GET_STATUS`_ +and `video_event`_ returned by `VIDEO_GET_EVENT`_ which report +about the display format of the current video stream. + + +----- + + +video_displayformat_t +--------------------- + +Synopsis +~~~~~~~~ + +.. code-block:: c + + typedef enum { + VIDEO_PAN_SCAN, + VIDEO_LETTER_BOX, + VIDEO_CENTER_CUT_OUT + } video_displayformat_t; + +Constants +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``VIDEO_PAN_SCAN`` + + - Use pan and scan format. + + - .. + + - ``VIDEO_LETTER_BOX`` + + - Use letterbox format. + + - .. + + - ``VIDEO_CENTER_CUT_OUT`` + + - Use center cut out format. + +Description +~~~~~~~~~~~ + +In case the display format of the video stream and of the display +hardware differ the application has to specify how to handle the +cropping of the picture. This can be done using the +`VIDEO_SET_DISPLAY_FORMAT`_ call which accepts this enum as argument. + + +----- + + +video_size_t +------------ + +Synopsis +~~~~~~~~ + +.. code-block:: c + + typedef struct { + int w; + int h; + video_format_t aspect_ratio; + } video_size_t; + +Variables +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int w`` + + - Video width in pixels. + + - .. + + - ``int h`` + + - Video height in pixels. + + - .. + + - `video_format_t`_ ``aspect_ratio`` + + - Aspect ratio. + +Description +~~~~~~~~~~~ + +Used in the struct `video_event`_. It stores the resolution and +aspect ratio of the video. + + +----- + + +video_stream_source_t +--------------------- + +Synopsis +~~~~~~~~ + +.. code-block:: c + + typedef enum { + VIDEO_SOURCE_DEMUX, + VIDEO_SOURCE_MEMORY + } video_stream_source_t; + +Constants +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``VIDEO_SOURCE_DEMUX`` + + - :cspan:`1` Select the demux as the main source. + + - .. + + - ``VIDEO_SOURCE_MEMORY`` + + - If this source is selected, the stream + comes from the user through the write + system call. + +Description +~~~~~~~~~~~ + +The video stream source is set through the `VIDEO_SELECT_SOURCE`_ call +and can take the following values, depending on whether we are replaying +from an internal (demuxer) or external (user write) source. +VIDEO_SOURCE_DEMUX selects the demultiplexer (fed either by the +frontend or the DVR device) as the source of the video stream. If +VIDEO_SOURCE_MEMORY is selected the stream comes from the application +through the `write()`_ system call. + + +----- + + +video_play_state_t +------------------ + +Synopsis +~~~~~~~~ + +.. code-block:: c + + typedef enum { + VIDEO_STOPPED, + VIDEO_PLAYING, + VIDEO_FREEZED + } video_play_state_t; + +Constants +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``VIDEO_STOPPED`` + + - Video is stopped. + + - .. + + - ``VIDEO_PLAYING`` + + - Video is currently playing. + + - .. + + - ``VIDEO_FREEZED`` + + - Video is frozen. + +Description +~~~~~~~~~~~ + +This values can be returned by the `VIDEO_GET_STATUS`_ call +representing the state of video playback. + + +----- + + +struct video_command +-------------------- + +Synopsis +~~~~~~~~ + +.. code-block:: c + + struct video_command { + __u32 cmd; + __u32 flags; + union { + struct { + __u64 pts; + } stop; + + struct { + __s32 speed; + __u32 format; + } play; + + struct { + __u32 data[16]; + } raw; + }; + }; + + +Variables +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``__u32 cmd`` + + - `Decoder command`_ + + - .. + + - ``__u32 flags`` + + - Flags for the `Decoder command`_. + + - .. + + - ``struct stop`` + + - ``__u64 pts`` + + - MPEG PTS + + - .. + + - :rspan:`5` ``stuct play`` + + - :rspan:`4` ``__s32 speed`` + + - 0 or 1000 specifies normal speed, + + - .. + + - 1: specifies forward single stepping, + + - .. + + - -1: specifies backward single stepping, + + - .. + + - >1: playback at speed / 1000 of the normal speed + + - .. + + - <-1: reverse playback at ( -speed / 1000 ) of the normal speed. + + - .. + + - ``__u32 format`` + + - `Play input formats`_ + + - .. + + - ``__u32 data[16]`` + + - Reserved + +Description +~~~~~~~~~~~ + +The structure must be zeroed before use by the application. This ensures +it can be extended safely in the future. + + +----- + + +Predefined decoder commands and flags +------------------------------------- + +Synopsis +~~~~~~~~ + +.. code-block:: c + + #define VIDEO_CMD_PLAY (0) + #define VIDEO_CMD_STOP (1) + #define VIDEO_CMD_FREEZE (2) + #define VIDEO_CMD_CONTINUE (3) + + #define VIDEO_CMD_FREEZE_TO_BLACK (1 << 0) + + #define VIDEO_CMD_STOP_TO_BLACK (1 << 0) + #define VIDEO_CMD_STOP_IMMEDIATELY (1 << 1) + + #define VIDEO_PLAY_FMT_NONE (0) + #define VIDEO_PLAY_FMT_GOP (1) + + #define VIDEO_VSYNC_FIELD_UNKNOWN (0) + #define VIDEO_VSYNC_FIELD_ODD (1) + #define VIDEO_VSYNC_FIELD_EVEN (2) + #define VIDEO_VSYNC_FIELD_PROGRESSIVE (3) + +Constants +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - :rspan:`3` _`Decoder command` + + - ``VIDEO_CMD_PLAY`` + + - Start playback. + + - .. + + - ``VIDEO_CMD_STOP`` + + - Stop playback. + + - .. + + - ``VIDEO_CMD_FREEZE`` + + - Freeze playback. + + - .. + + - ``VIDEO_CMD_CONTINUE`` + + - Continue playback after freeze. + + - .. + + - Flags for ``VIDEO_CMD_FREEZE`` + + - ``VIDEO_CMD_FREEZE_TO_BLACK`` + + - Show black picture on freeze. + + - .. + + - :rspan:`1` Flags for ``VIDEO_CMD_STOP`` + + - ``VIDEO_CMD_STOP_TO_BLACK`` + + - Show black picture on stop. + + - .. + + - ``VIDEO_CMD_STOP_IMMEDIATELY`` + + - Stop immediately, without emptying buffers. + + - .. + + - :rspan:`1` _`Play input formats` + + - ``VIDEO_PLAY_FMT_NONE`` + + - The decoder has no special format requirements + + - .. + + - ``VIDEO_PLAY_FMT_GOP`` + + - The decoder requires full GOPs + + - .. + + - :rspan:`3` Field order + + - ``VIDEO_VSYNC_FIELD_UNKNOWN`` + + - FIELD_UNKNOWN can be used if the hardware does not know + whether the Vsync is for an odd, even or progressive + (i.e. non-interlaced) field. + + - .. + + - ``VIDEO_VSYNC_FIELD_ODD`` + + - Vsync is for an odd field. + + - .. + + - ``VIDEO_VSYNC_FIELD_EVEN`` + + - Vsync is for an even field. + + - .. + + - ``VIDEO_VSYNC_FIELD_PROGRESSIVE`` + + - progressive (i.e. non-interlaced) + + +----- + + +video_event +----------- + +Synopsis +~~~~~~~~ + +.. code-block:: c + + struct video_event { + __s32 type; + #define VIDEO_EVENT_SIZE_CHANGED 1 + #define VIDEO_EVENT_FRAME_RATE_CHANGED 2 + #define VIDEO_EVENT_DECODER_STOPPED 3 + #define VIDEO_EVENT_VSYNC 4 + long timestamp; + union { + video_size_t size; + unsigned int frame_rate; + unsigned char vsync_field; + } u; + }; + +Variables +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - :rspan:`4` ``__s32 type`` + + - :cspan:`1` Event type. + + - .. + + - ``VIDEO_EVENT_SIZE_CHANGED`` + + - Size changed. + + - .. + + - ``VIDEO_EVENT_FRAME_RATE_CHANGED`` + + - Framerate changed. + + - .. + + - ``VIDEO_EVENT_DECODER_STOPPED`` + + - Decoder stopped. + + - .. + + - ``VIDEO_EVENT_VSYNC`` + + - Vsync occurred. + + - .. + + - ``long timestamp`` + + - :cspan:`1` MPEG PTS at occurrence. + + - .. + + - :rspan:`2` ``union u`` + + - `video_size_t`_ size + + - Resolution and aspect ratio of the video. + + - .. + + - ``unsigned int frame_rate`` + + - in frames per 1000sec + + - .. + + - ``unsigned char vsync_field`` + + - | unknown / odd / even / progressive + | See: `Predefined decoder commands and flags`_ + +Description +~~~~~~~~~~~ + +This is the structure of a video event as it is returned by the +`VIDEO_GET_EVENT`_ call. See there for more details. + + +----- + + +video_status +------------ + +Synopsis +~~~~~~~~ + +The `VIDEO_GET_STATUS`_ call returns the following structure informing +about various states of the playback operation. + +.. code-block:: c + + struct video_status { + int video_blank; + video_play_state_t play_state; + video_stream_source_t stream_source; + video_format_t video_format; + video_displayformat_t display_format; + }; + +Variables +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - :rspan:`2` ``int video_blank`` + + - :cspan:`1` Show blank video on freeze? + + - .. + + - TRUE ( != 0 ) + + - Blank screen when freeze. + + - .. + + - FALSE ( == 0 ) + + - Show last decoded frame. + + - .. + + - `video_play_state_t`_ ``play_state`` + + - Current state of playback. + + - .. + + - `video_stream_source_t`_ ``stream_source`` + + - Current source (demux/memory). + + - .. + + - `video_format_t`_ ``video_format`` + + - Current aspect ratio of stream. + + - .. + + - `video_displayformat_t`_ ``display_format`` + + - Applied cropping mode. + +Description +~~~~~~~~~~~ + +If ``video_blank`` is set ``TRUE`` video will be blanked out if the +channel is changed or if playback is stopped. Otherwise, the last picture +will be displayed. ``play_state`` indicates if the video is currently +frozen, stopped, or being played back. The ``stream_source`` corresponds +to the selected source for the video stream. It can come either from the +demultiplexer or from memory. The ``video_format`` indicates the aspect +ratio (one of 4:3 or 16:9) of the currently played video stream. +Finally, ``display_format`` corresponds to the applied cropping mode in +case the source video format is not the same as the format of the output +device. + + +----- + + +video_still_picture +------------------- + +Synopsis +~~~~~~~~ + +.. code-block:: c + + struct video_still_picture { + char *iFrame; + int32_t size; + }; + +Variables +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``char *iFrame`` + + - Pointer to a single iframe in memory. + + - .. + + - ``int32_t size`` + + - Size of the iframe. + + +Description +~~~~~~~~~~~ + +An I-frame displayed via the `VIDEO_STILLPICTURE`_ call is passed on +within this structure. + + +----- + + +video capabilities +------------------ + +Synopsis +~~~~~~~~ + +.. code-block:: c + + #define VIDEO_CAP_MPEG1 1 + #define VIDEO_CAP_MPEG2 2 + #define VIDEO_CAP_SYS 4 + #define VIDEO_CAP_PROG 8 + +Constants +~~~~~~~~~ +Bit definitions for capabilities: + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``VIDEO_CAP_MPEG1`` + + - :cspan:`1` The hardware can decode MPEG1. + + - .. + + - ``VIDEO_CAP_MPEG2`` + + - The hardware can decode MPEG2. + + - .. + + - ``VIDEO_CAP_SYS`` + + - The video device accepts system stream. + + You still have to open the video and the audio device + but only send the stream to the video device. + + - .. + + - ``VIDEO_CAP_PROG`` + + - The video device accepts program stream. + + You still have to open the video and the audio device + but only send the stream to the video device. + +Description +~~~~~~~~~~~ + +A call to `VIDEO_GET_CAPABILITIES`_ returns an unsigned integer with the +following bits set according to the hardware's capabilities. + + +----- + + +Video Function Calls +==================== + + +VIDEO_STOP +---------- + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_STOP + +.. code-block:: c + + int ioctl(fd, VIDEO_STOP, int mode) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - :cspan:`1` Equals ``VIDEO_STOP`` for this command. + + - .. + + - :rspan:`2` ``int mode`` + + - :cspan:`1` Indicates how the screen shall be handled. + + - .. + + - TRUE ( != 0 ) + + - Blank screen when stop. + + - .. + + - FALSE ( == 0 ) + + - Show last decoded frame. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +This ioctl is for Digital TV devices only. To control a V4L2 decoder use +the V4L2 :ref:`VIDIOC_DECODER_CMD` instead. + +This ioctl call asks the Video Device to stop playing the current +stream. Depending on the input parameter, the screen can be blanked out +or displaying the last decoded frame. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +VIDEO_PLAY +---------- + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_PLAY + +.. code-block:: c + + int ioctl(fd, VIDEO_PLAY) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_PLAY`` for this command. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +This ioctl is for Digital TV devices only. To control a V4L2 decoder use +the V4L2 :ref:`VIDIOC_DECODER_CMD` instead. + +This ioctl call asks the Video Device to start playing a video stream +from the selected source. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +VIDEO_FREEZE +------------ + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_FREEZE + +.. code-block:: c + + int ioctl(fd, VIDEO_FREEZE) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_FREEZE`` for this command. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +This ioctl is for Digital TV devices only. To control a V4L2 decoder use +the V4L2 :ref:`VIDIOC_DECODER_CMD` instead. + +This ioctl call suspends the live video stream being played, if +VIDEO_SOURCE_DEMUX is selected. Decoding and playing are frozen. +It is then possible to restart the decoding and playing process of the +video stream using the `VIDEO_CONTINUE`_ command. +If VIDEO_SOURCE_MEMORY is selected in the ioctl call +`VIDEO_SELECT_SOURCE`_, the Digital TV subsystem will not decode any more +data until the ioctl call `VIDEO_CONTINUE`_ or `VIDEO_PLAY`_ is performed. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +VIDEO_CONTINUE +-------------- + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_CONTINUE + +.. code-block:: c + + int ioctl(fd, VIDEO_CONTINUE) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_CONTINUE`` for this command. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +This ioctl is for Digital TV devices only. To control a V4L2 decoder use +the V4L2 :ref:`VIDIOC_DECODER_CMD` instead. + +This ioctl call restarts decoding and playing processes of the video +stream which was played before a call to `VIDEO_FREEZE`_ was made. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +VIDEO_SELECT_SOURCE +------------------- + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_SELECT_SOURCE + +.. code-block:: c + + int ioctl(fd, VIDEO_SELECT_SOURCE, video_stream_source_t source) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_SELECT_SOURCE`` for this command. + + - .. + + - `video_stream_source_t`_ ``source`` + + - Indicates which source shall be used for the Video stream. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +This ioctl is for Digital TV devices only. This ioctl was also supported +by the V4L2 ivtv driver, but that has been replaced by the ivtv-specific +``IVTV_IOC_PASSTHROUGH_MODE`` ioctl. + +This ioctl call informs the video device which source shall be used for +the input data. The possible sources are demux or memory. If memory is +selected, the data is fed to the video device through the write command +using the struct `video_stream_source_t`_. If demux is selected, the data +is directly transferred from the onboard demux-device to the decoder. + +The data fed to the decoder is also controlled by the PID-filter. +Output selection: :c:type:`dmx_output` ``DMX_OUT_DECODER``. + + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +VIDEO_SET_BLANK +--------------- + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_SET_BLANK + +.. code-block:: c + + int ioctl(fd, VIDEO_SET_BLANK, int mode) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - :cspan:`1` Equals ``VIDEO_SET_BLANK`` for this command. + + - .. + + - :rspan:`2` ``int mode`` + + - :cspan:`1` Indicates if the screen shall be blanked. + + - .. + + - TRUE ( != 0 ) + + - Blank screen when stop. + + - .. + + - FALSE ( == 0 ) + + - Show last decoded frame. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +This ioctl call asks the Video Device to blank out the picture. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +VIDEO_GET_STATUS +---------------- + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_GET_STATUS + +.. code-block:: c + + int ioctl(fd, int request = VIDEO_GET_STATUS, + struct video_status *status) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_GET_STATUS`` for this command. + + - .. + + - ``struct`` `video_status`_ ``*status`` + + - Returns the current status of the Video Device. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +This ioctl call asks the Video Device to return the current status of +the device. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +VIDEO_GET_EVENT +--------------- + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_GET_EVENT + +.. code-block:: c + + int ioctl(fd, int request = VIDEO_GET_EVENT, + struct video_event *ev) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_GET_EVENT`` for this command. + + - .. + + - ``struct`` `video_event`_ ``*ev`` + + - Points to the location where the event, if any, is to be stored. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +This ioctl is for DVB devices only. To get events from a V4L2 decoder +use the V4L2 :ref:`VIDIOC_DQEVENT` ioctl instead. + +This ioctl call returns an event of type `video_event`_ if available. A +certain number of the latest events will be cued and returned in order of +occurrence. Older events may be discarded if not fetched in time. If +an event is not available, the behavior depends on whether the device is +in blocking or non-blocking mode. In the latter case, the call fails +immediately with errno set to ``EWOULDBLOCK``. In the former case, the +call blocks until an event becomes available. The standard Linux poll() +and/or select() system calls can be used with the device file descriptor +to watch for new events. For select(), the file descriptor should be +included in the exceptfds argument, and for poll(), POLLPRI should be +specified as the wake-up condition. Read-only permissions are sufficient +for this ioctl call. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``EWOULDBLOCK`` + + - :cspan:`1` There is no event pending, and the device is in + non-blocking mode. + + - .. + + - ``EOVERFLOW`` + + - Overflow in event queue - one or more events were lost. + + +----- + + +VIDEO_SET_DISPLAY_FORMAT +------------------------ + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_SET_DISPLAY_FORMAT + +.. code-block:: c + + int ioctl(fd, int request = VIDEO_SET_DISPLAY_FORMAT, + video_display_format_t format) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_SET_DISPLAY_FORMAT`` for this command. + + - .. + + - `video_displayformat_t`_ ``format`` + + - Selects the video format to be used. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +This ioctl call asks the Video Device to select the video format to be +applied by the MPEG chip on the video. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +VIDEO_STILLPICTURE +------------------ + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_STILLPICTURE + +.. code-block:: c + + int ioctl(fd, int request = VIDEO_STILLPICTURE, + struct video_still_picture *sp) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_STILLPICTURE`` for this command. + + - .. + + - ``struct`` `video_still_picture`_ ``*sp`` + + - Pointer to the location where the struct with the I-frame + and size is stored. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +This ioctl call asks the Video Device to display a still picture +(I-frame). The input data shall be the section of an elementary video +stream containing an I-frame. Typically this section is extracted from a +TS or PES recording. Resolution and codec (see `video capabilities`_) must +be supported by the device. If the pointer is NULL, then the current +displayed still picture is blanked. + +e.g. The AV7110 supports MPEG1 and MPEG2 with the common PAL-SD +resolutions. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +VIDEO_FAST_FORWARD +------------------ + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_FAST_FORWARD + +.. code-block:: c + + int ioctl(fd, int request = VIDEO_FAST_FORWARD, int nFrames) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_FAST_FORWARD`` for this command. + + - .. + + - ``int nFrames`` + + - The number of frames to skip. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +This ioctl call asks the Video Device to skip decoding of N number of +I-frames. This call can only be used if ``VIDEO_SOURCE_MEMORY`` is +selected. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``EPERM`` + + - Mode ``VIDEO_SOURCE_MEMORY`` not selected. + + +----- + + +VIDEO_SLOWMOTION +---------------- + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_SLOWMOTION + +.. code-block:: c + + int ioctl(fd, int request = VIDEO_SLOWMOTION, int nFrames) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_SLOWMOTION`` for this command. + + - .. + + - ``int nFrames`` + + - The number of times to repeat each frame. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +This ioctl call asks the video device to repeat decoding frames N number +of times. This call can only be used if ``VIDEO_SOURCE_MEMORY`` is +selected. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``EPERM`` + + - Mode ``VIDEO_SOURCE_MEMORY`` not selected. + + +----- + + +VIDEO_GET_CAPABILITIES +---------------------- + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_GET_CAPABILITIES + +.. code-block:: c + + int ioctl(fd, int request = VIDEO_GET_CAPABILITIES, unsigned int *cap) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_GET_CAPABILITIES`` for this command. + + - .. + + - ``unsigned int *cap`` + + - Pointer to a location where to store the capability information. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +This ioctl call asks the video device about its decoding capabilities. +On success it returns an integer which has bits set according to the +defines in `video capabilities`_. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +VIDEO_CLEAR_BUFFER +------------------ + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_CLEAR_BUFFER + +.. code-block:: c + + int ioctl(fd, int request = VIDEO_CLEAR_BUFFER) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_CLEAR_BUFFER`` for this command. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +This ioctl call clears all video buffers in the driver and in the +decoder hardware. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +VIDEO_SET_STREAMTYPE +-------------------- + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_SET_STREAMTYPE + +.. code-block:: c + + int ioctl(fd, int request = VIDEO_SET_STREAMTYPE, int type) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_SET_STREAMTYPE`` for this command. + + - .. + + - ``int type`` + + - Stream type. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +This ioctl tells the driver which kind of stream to expect being written +to it. +Intelligent decoder might also not support or ignore (like the AV7110) +this call and determine the stream type themselves. + +Currently used stream types: + +.. flat-table:: + :header-rows: 1 + :stub-columns: 0 + + - .. + + - Codec + + - Stream type + + - .. + + - MPEG2 + + - 0 + + - .. + + - MPEG4 h.264 + + - 1 + + - .. + + - VC1 + + - 3 + + - .. + + - MPEG4 Part2 + + - 4 + + - .. + + - VC1 SM + + - 5 + + - .. + + - MPEG1 + + - 6 + + - .. + + - HEVC h.265 + + - | 7 + | DREAMBOX: 22 + + - .. + + - AVS + + - 16 + + - .. + + - AVS2 + + - 40 + +Not every decoder supports all stream types. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +VIDEO_SET_FORMAT +---------------- + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_SET_FORMAT + +.. code-block:: c + + int ioctl(fd, int request = VIDEO_SET_FORMAT, video_format_t format) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_SET_FORMAT`` for this command. + + - .. + + - `video_format_t`_ ``format`` + + - Video format of TV as defined in section `video_format_t`_. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +This ioctl sets the screen format (aspect ratio) of the connected output +device (TV) so that the output of the decoder can be adjusted +accordingly. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +VIDEO_GET_SIZE +-------------- + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_GET_SIZE + +.. code-block:: c + + int ioctl(int fd, int request = VIDEO_GET_SIZE, video_size_t *size) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call, + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_GET_SIZE`` for this command. + + - .. + + - `video_size_t`_ ``*size`` + + - Returns the size and aspect ratio. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +This ioctl returns the size and aspect ratio. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +VIDEO_GET_PTS +------------- + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_GET_PTS + +.. code-block:: c + + int ioctl(int fd, int request = VIDEO_GET_PTS, __u64 *pts) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_GET_PTS`` for this command. + + - .. + + - ``__u64 *pts`` + + - Returns the 33-bit timestamp as defined in ITU T-REC-H.222.0 / + ISO/IEC 13818-1. + + The PTS should belong to the currently played frame if possible, + but may also be a value close to it like the PTS of the last + decoded frame or the last PTS extracted by the PES parser. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +For V4L2 decoders this ioctl has been replaced by the +``V4L2_CID_MPEG_VIDEO_DEC_PTS`` control. + +This ioctl call asks the Video Device to return the current PTS +timestamp. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +VIDEO_GET_FRAME_COUNT +--------------------- + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_GET_FRAME_COUNT + +.. code-block:: c + + int ioctl(int fd, VIDEO_GET_FRAME_COUNT, __u64 *pts) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_GET_FRAME_COUNT`` for this command. + + - .. + + - ``__u64 *pts`` + + - Returns the number of frames displayed since the decoder was + started. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +For V4L2 decoders this ioctl has been replaced by the +``V4L2_CID_MPEG_VIDEO_DEC_FRAME`` control. + +This ioctl call asks the Video Device to return the number of displayed +frames since the decoder was started. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +VIDEO_COMMAND +------------- + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_COMMAND + +.. code-block:: c + + int ioctl(int fd, int request = VIDEO_COMMAND, + struct video_command *cmd) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_COMMAND`` for this command. + + - .. + + - `struct video_command`_ ``*cmd`` + + - Commands the decoder. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +For V4L2 decoders this ioctl has been replaced by the +:ref:`VIDIOC_DECODER_CMD` ioctl. + +This ioctl commands the decoder. The `struct video_command`_ is a +subset of the ``v4l2_decoder_cmd`` struct, so refer to the +:ref:`VIDIOC_DECODER_CMD` documentation for +more information. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +VIDEO_TRY_COMMAND +----------------- + +Synopsis +~~~~~~~~ + +.. c:macro:: VIDEO_TRY_COMMAND + +.. code-block:: c + + int ioctl(int fd, int request = VIDEO_TRY_COMMAND, + struct video_command *cmd) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``int request`` + + - Equals ``VIDEO_TRY_COMMAND`` for this command. + + - .. + + - `struct video_command`_ ``*cmd`` + + - Try a decoder command. + +Description +~~~~~~~~~~~ + +.. attention:: Do **not** use in new drivers! + See: :ref:`legacy_dvb_decoder_notes` + +For V4L2 decoders this ioctl has been replaced by the +:ref:`VIDIOC_TRY_DECODER_CMD <VIDIOC_DECODER_CMD>` ioctl. + +This ioctl tries a decoder command. The `struct video_command`_ is a +subset of the ``v4l2_decoder_cmd`` struct, so refer to the +:ref:`VIDIOC_TRY_DECODER_CMD <VIDIOC_DECODER_CMD>` documentation +for more information. + +Return Value +~~~~~~~~~~~~ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. + + +----- + + +open() +------ + +Synopsis +~~~~~~~~ + +.. code-block:: c + + #include <fcntl.h> + +.. c:function:: int open(const char *deviceName, int flags) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``const char *deviceName`` + + - Name of specific video device. + + - .. + + - :rspan:`3` ``int flags`` + + - :cspan:`1` A bit-wise OR of the following flags: + + - .. + + - ``O_RDONLY`` + + - read-only access + + - .. + + - ``O_RDWR`` + + - read/write access + + - .. + + - ``O_NONBLOCK`` + - | Open in non-blocking mode + | (blocking mode is the default) + +Description +~~~~~~~~~~~ + +This system call opens a named video device (e.g. +/dev/dvb/adapter?/video?) for subsequent use. + +When an open() call has succeeded, the device will be ready for use. The +significance of blocking or non-blocking mode is described in the +documentation for functions where there is a difference. It does not +affect the semantics of the open() call itself. A device opened in +blocking mode can later be put into non-blocking mode (and vice versa) +using the F_SETFL command of the fcntl system call. This is a standard +system call, documented in the Linux manual page for fcntl. Only one +user can open the Video Device in O_RDWR mode. All other attempts to +open the device in this mode will fail, and an error-code will be +returned. If the Video Device is opened in O_RDONLY mode, the only +ioctl call that can be used is `VIDEO_GET_STATUS`_. All other call will +return an error code. + +Return Value +~~~~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``ENODEV`` + + - :cspan:`1` Device driver not loaded/available. + + - .. + + - ``EINTERNAL`` + + - Internal error. + + - .. + + - ``EBUSY`` + + - Device or resource busy. + + - .. + + - ``EINVAL`` + + - Invalid argument. + + +----- + + +close() +------- + +Synopsis +~~~~~~~~ + +.. c:function:: int close(int fd) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + +Description +~~~~~~~~~~~ + +This system call closes a previously opened video device. + +Return Value +~~~~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``EBADF`` + + - fd is not a valid open file descriptor. + + +----- + + +write() +------- + +Synopsis +~~~~~~~~ + +.. c:function:: size_t write(int fd, const void *buf, size_t count) + +Arguments +~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``int fd`` + + - :cspan:`1` File descriptor returned by a previous call + to `open()`_. + + - .. + + - ``void *buf`` + + - Pointer to the buffer containing the PES data. + + - .. + + - ``size_t count`` + + - Size of buf. + +Description +~~~~~~~~~~~ + +This system call can only be used if VIDEO_SOURCE_MEMORY is selected +in the ioctl call `VIDEO_SELECT_SOURCE`_. The data provided shall be in +PES format, unless the capability allows other formats. TS is the +most common format for storing DVB-data, it is usually supported too. +If O_NONBLOCK is not specified the function will block until buffer space +is available. The amount of data to be transferred is implied by count. + +.. note:: See: :ref:`DVB Data Formats <legacy_dvb_decoder_formats>` + +Return Value +~~~~~~~~~~~~ + +.. flat-table:: + :header-rows: 0 + :stub-columns: 0 + + - .. + + - ``EPERM`` + + - :cspan:`1` Mode ``VIDEO_SOURCE_MEMORY`` not selected. + + - .. + + - ``ENOMEM`` + + - Attempted to write more data than the internal buffer can hold. + + - .. + + - ``EBADF`` + + - fd is not a valid open file descriptor. |