v4l2.c

vlc源码

/*****************************************************************************
 * v4l2.c : Video4Linux2 input module for vlc
 *****************************************************************************
 * Copyright (C) 2002-2007 the VideoLAN team
 * $Id: a1e52526f58a94c4f1e0c26a798f2b3633a8e0a8 $
 *
 * Authors: Benjamin Pracht <bigben at videolan dot org>
 *          Richard Hosking <richard at hovis dot net>
 *          Antoine Cellerier <dionoea at videolan d.t org>
 *          Dennis Lou <dlou99 at yahoo dot com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
 *****************************************************************************/

/*
 * Sections based on the reference V4L2 capture example at
 * http://v4l2spec.bytesex.org/spec/capture-example.html
 *
 * ALSA support based on parts of
 * http://www.equalarea.com/paul/alsa-audio.html
 * and hints taken from alsa-utils (aplay/arecord)
 * http://www.alsa-project.org
 */

/*****************************************************************************
 * Preamble
 *****************************************************************************/

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include <vlc_common.h>
#include <vlc_plugin.h>
#include <vlc_access.h>
#include <vlc_demux.h>
#include <vlc_input.h>
#include <vlc_vout.h>

#include <ctype.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/mman.h>

#include <linux/videodev2.h>

#include <sys/soundcard.h>

#ifdef HAVE_ALSA
#   define ALSA_PCM_NEW_HW_PARAMS_API
#   define ALSA_PCM_NEW_SW_PARAMS_API
#   include <alsa/asoundlib.h>
#endif

#include <poll.h>

#ifdef HAVE_LIBV4L2
#   include <libv4l2.h>
#else
#   define v4l2_fd_open(fd, flags) (fd)
#   define v4l2_close close
#   define v4l2_dup dup
#   define v4l2_ioctl ioctl
#   define v4l2_read read
#   define v4l2_mmap mmap
#   define v4l2_munmap munmap
#endif

/*****************************************************************************
 * Module descriptior
 *****************************************************************************/

static int  DemuxOpen ( vlc_object_t * );
static void DemuxClose( vlc_object_t * );
static int  AccessOpen ( vlc_object_t * );
static void AccessClose( vlc_object_t * );

#define DEV_TEXT N_("Device name")
#define DEV_LONGTEXT N_( \
    "Name of the device to use. " \
    "If you don't specify anything, /dev/video0 will be used.")
#define STANDARD_TEXT N_( "Standard" )
#define STANDARD_LONGTEXT N_( \
    "Video standard (Default, SECAM, PAL, or NTSC)." )
#define CHROMA_TEXT N_("Video input chroma format")
#define CHROMA_LONGTEXT N_( \
    "Force the Video4Linux2 video device to use a specific chroma format " \
    "(eg. I420 or I422 for raw images, MJPG for M-JPEG compressed input) " \
    "(Complete list: GREY, I240, RV16, RV15, RV24, RV32, YUY2, YUYV, UYVY, " \
    "I41N, I422, I420, I411, I410, MJPG)")
#define INPUT_TEXT N_( "Input" )
#define INPUT_LONGTEXT N_( \
    "Input of the card to use (see debug)." )
#define AUDIO_INPUT_TEXT N_( "Audio input" )
#define AUDIO_INPUT_LONGTEXT N_( \
    "Audio input of the card to use (see debug)." )
#define IOMETHOD_TEXT N_( "IO Method" )
#define IOMETHOD_LONGTEXT N_( \
    "IO Method (READ, MMAP, USERPTR)." )
#define WIDTH_TEXT N_( "Width" )
#define WIDTH_LONGTEXT N_( \
    "Force width (-1 for autodetect)." )
#define HEIGHT_TEXT N_( "Height" )
#define HEIGHT_LONGTEXT N_( \
    "Force height (-1 for autodetect)." )
#define FPS_TEXT N_( "Framerate" )
#define FPS_LONGTEXT N_( "Framerate to capture, if applicable " \
    "(-1 for autodetect)." )

#define CTRL_RESET_TEXT N_( "Reset v4l2 controls" )
#define CTRL_RESET_LONGTEXT N_( \
    "Reset controls to defaults provided by the v4l2 driver." )
#define BRIGHTNESS_TEXT N_( "Brightness" )
#define BRIGHTNESS_LONGTEXT N_( \
    "Brightness of the video input (if supported by the v4l2 driver)." )
#define CONTRAST_TEXT N_( "Contrast" )
#define CONTRAST_LONGTEXT N_( \
    "Contrast of the video input (if supported by the v4l2 driver)." )
#define SATURATION_TEXT N_( "Saturation" )
#define SATURATION_LONGTEXT N_( \
    "Saturation of the video input (if supported by the v4l2 driver)." )
#define HUE_TEXT N_( "Hue" )
#define HUE_LONGTEXT N_( \
    "Hue of the video input (if supported by the v4l2 driver)." )
#define BLACKLEVEL_TEXT N_( "Black level" )
#define BLACKLEVEL_LONGTEXT N_( \
    "Black level of the video input (if supported by the v4l2 driver)." )
#define AUTOWHITEBALANCE_TEXT N_( "Auto white balance" )
#define AUTOWHITEBALANCE_LONGTEXT N_( \
    "Automatically set the white balance of the video input " \
    "(if supported by the v4l2 driver)." )
#define DOWHITEBALANCE_TEXT N_( "Do white balance" )
#define DOWHITEBALANCE_LONGTEXT N_( \
    "Trigger a white balancing action, useless if auto white balance is " \
    "activated (if supported by the v4l2 driver)." )
#define REDBALANCE_TEXT N_( "Red balance" )
#define REDBALANCE_LONGTEXT N_( \
    "Red balance of the video input (if supported by the v4l2 driver)." )
#define BLUEBALANCE_TEXT N_( "Blue balance" )
#define BLUEBALANCE_LONGTEXT N_( \
    "Blue balance of the video input (if supported by the v4l2 driver)." )
#define GAMMA_TEXT N_( "Gamma" )
#define GAMMA_LONGTEXT N_( \
    "Gamma of the video input (if supported by the v4l2 driver)." )
#define EXPOSURE_TEXT N_( "Exposure" )
#define EXPOSURE_LONGTEXT N_( \
    "Exposure of the video input (if supported by the v4L2 driver)." )
#define AUTOGAIN_TEXT N_( "Auto gain" )
#define AUTOGAIN_LONGTEXT N_( \
    "Automatically set the video input's gain (if supported by the " \
    "v4l2 driver)." )
#define GAIN_TEXT N_( "Gain" )
#define GAIN_LONGTEXT N_( \
    "Video input's gain (if supported by the v4l2 driver)." )
#define HFLIP_TEXT N_( "Horizontal flip" )
#define HFLIP_LONGTEXT N_( \
    "Flip the video horizontally (if supported by the v4l2 driver)." )
#define VFLIP_TEXT N_( "Vertical flip" )
#define VFLIP_LONGTEXT N_( \
    "Flip the video vertically (if supported by the v4l2 driver)." )
#define HCENTER_TEXT N_( "Horizontal centering" )
#define HCENTER_LONGTEXT N_( \
    "Set the camera's horizontal centering (if supported by the v4l2 driver)." )
#define VCENTER_TEXT N_( "Vertical centering" )
#define VCENTER_LONGTEXT N_( \
    "Set the camera's vertical centering (if supported by the v4l2 driver)." )

#define ADEV_TEXT N_("Audio device name")
#ifndef HAVE_ALSA
#define ADEV_LONGTEXT N_( \
    "Name of the audio device to use. " \
    "If you don't specify anything, \"/dev/dsp\" will be used for OSS.")
#else
#define ADEV_LONGTEXT N_( \
    "Name of the audio device to use. " \
    "If you don't specify anything, \"/dev/dsp\" will be used for OSS, " \
    "\"hw\" for Alsa.")
#endif
#define AUDIO_METHOD_TEXT N_( "Audio method" )
#ifndef HAVE_ALSA
#define AUDIO_METHOD_LONGTEXT N_( \
    "Audio method to use: 0 to disable audio, 1 for OSS." )
#else
#define AUDIO_METHOD_LONGTEXT N_( \
    "Audio method to use: 0 to disable audio, 1 for OSS, 2 for ALSA, " \
    "3 for ALSA or OSS (ALSA is preferred)." )
#endif
#define AUDIO_VOLUME_TEXT N_( "Volume" )
#define AUDIO_VOLUME_LONGTEXT N_( \
    "Volume of the audio input (if supported by the v4l2 driver)." )
#define AUDIO_BALANCE_TEXT N_( "Balance" )
#define AUDIO_BALANCE_LONGTEXT N_( \
    "Balance of the audio input (if supported by the v4l2 driver)." )
#define AUDIO_MUTE_TEXT N_( "Mute" )
#define AUDIO_MUTE_LONGTEXT N_( \
    "Mute audio input (if supported by the v4l2 driver)." )
#define AUDIO_BASS_TEXT N_( "Bass" )
#define AUDIO_BASS_LONGTEXT N_( \
    "Bass level of the audio input (if supported by the v4l2 driver)." )
#define AUDIO_TREBLE_TEXT N_( "Treble" )
#define AUDIO_TREBLE_LONGTEXT N_( \
    "Treble level of the audio input (if supported by the v4l2 driver)." )
#define AUDIO_LOUDNESS_TEXT N_( "Loudness" )
#define AUDIO_LOUDNESS_LONGTEXT N_( \
    "Loudness of the audio input (if supported by the v4l2 driver)." )

#define STEREO_TEXT N_( "Stereo" )
#define STEREO_LONGTEXT N_( \
    "Capture the audio stream in stereo." )
#define SAMPLERATE_TEXT N_( "Samplerate" )
#define SAMPLERATE_LONGTEXT N_( \
    "Samplerate of the captured audio stream, in Hz (eg: 11025, 22050, 44100, 48000)" )

#define CACHING_TEXT N_("Caching value in ms")
#define CACHING_LONGTEXT N_( \
    "Caching value for V4L2 captures. This " \
    "value should be set in milliseconds." )
#define S_CTRLS_TEXT N_("v4l2 driver controls")
#define S_CTRLS_LONGTEXT N_( \
    "Set the v4l2 driver controls to the values specified using a comma " \
    "separated list optionally encapsulated by curly braces " \
    "(e.g.: {video_bitrate=6000000,audio_crc=0,stream_type=3} ). " \
    "To list available controls, increase verbosity (-vvv) " \
    "or use the v4l2-ctl application." )

#define TUNER_TEXT N_("Tuner id")
#define TUNER_LONGTEXT N_( \
    "Tuner id (see debug output)." )
#define FREQUENCY_TEXT N_("Frequency")
#define FREQUENCY_LONGTEXT N_( \
    "Tuner frequency in Hz or kHz (see debug output)" )
#define TUNER_AUDIO_MODE_TEXT N_("Audio mode")
#define TUNER_AUDIO_MODE_LONGTEXT N_( \
    "Tuner audio mono/stereo and track selection." )

typedef enum {
    IO_METHOD_READ,
    IO_METHOD_MMAP,
    IO_METHOD_USERPTR,
} io_method;

static const int i_standards_list[] =
    { V4L2_STD_UNKNOWN, V4L2_STD_SECAM, V4L2_STD_PAL, V4L2_STD_NTSC };
static const char *const psz_standards_list_text[] =
    { N_("Default"), N_("SECAM"), N_("PAL"),  N_("NTSC") };

static const int i_iomethod_list[] =
    { IO_METHOD_READ, IO_METHOD_MMAP, IO_METHOD_USERPTR };
static const char *const psz_iomethod_list_text[] =
    { N_("READ"), N_("MMAP"),  N_("USERPTR") };

static const int i_tuner_audio_modes_list[] =
    { V4L2_TUNER_MODE_MONO, V4L2_TUNER_MODE_STEREO,
      V4L2_TUNER_MODE_LANG1, V4L2_TUNER_MODE_LANG2,
      V4L2_TUNER_MODE_SAP, V4L2_TUNER_MODE_LANG1_LANG2 };
static const char *const psz_tuner_audio_modes_list_text[] =
    { N_( "Mono" ),
      N_( "Stereo" ),
      N_( "Primary language (Analog TV tuners only)" ),
      N_( "Secondary language (Analog TV tuners only)" ),
      N_( "Second audio program (Analog TV tuners only)" ),
      N_( "Primary language left, Secondary language right" ) };

#define FIND_VIDEO 1
#define FIND_AUDIO 2

#define AUDIO_METHOD_OSS 1
#define OSS_DEFAULT "/dev/dsp"
#define AUDIO_METHOD_ALSA 2
#define ALSA_DEFAULT "hw"
#define CFG_PREFIX "v4l2-"

vlc_module_begin();
    set_shortname( N_("Video4Linux2") );
    set_description( N_("Video4Linux2 input") );
    set_category( CAT_INPUT );
    set_subcategory( SUBCAT_INPUT_ACCESS );

    set_section( N_( "Video input" ), NULL );
    add_string( CFG_PREFIX "dev", "/dev/video0", 0, DEV_TEXT, DEV_LONGTEXT,
                false );
    add_integer( CFG_PREFIX "standard", 0, NULL, STANDARD_TEXT,
                 STANDARD_LONGTEXT, false );
        change_integer_list( i_standards_list, psz_standards_list_text, NULL );
    add_string( CFG_PREFIX "chroma", NULL, NULL, CHROMA_TEXT, CHROMA_LONGTEXT,
                true );
    add_integer( CFG_PREFIX "input", 0, NULL, INPUT_TEXT, INPUT_LONGTEXT,
                true );
    add_integer( CFG_PREFIX "audio-input", 0, NULL, AUDIO_INPUT_TEXT,
                 AUDIO_INPUT_LONGTEXT, true );
    add_integer( CFG_PREFIX "io", IO_METHOD_MMAP, NULL, IOMETHOD_TEXT,
                 IOMETHOD_LONGTEXT, true );
        change_integer_list( i_iomethod_list, psz_iomethod_list_text, NULL );
    add_integer( CFG_PREFIX "width", 0, NULL, WIDTH_TEXT,
                WIDTH_LONGTEXT, true );
    add_integer( CFG_PREFIX "height", 0, NULL, HEIGHT_TEXT,
                HEIGHT_LONGTEXT, true );
    add_float( CFG_PREFIX "fps", 0, NULL, FPS_TEXT, FPS_LONGTEXT, true );

    set_section( N_( "Audio input" ), NULL );
    add_string( CFG_PREFIX "adev", NULL, 0, ADEV_TEXT, ADEV_LONGTEXT,
                false );
    add_integer( CFG_PREFIX "audio-method", AUDIO_METHOD_OSS|AUDIO_METHOD_ALSA,
                 NULL, AUDIO_METHOD_TEXT, AUDIO_METHOD_LONGTEXT, true );
    add_bool( CFG_PREFIX "stereo", true, NULL, STEREO_TEXT, STEREO_LONGTEXT,
                true );
    add_integer( CFG_PREFIX "samplerate", 48000, NULL, SAMPLERATE_TEXT,
                SAMPLERATE_LONGTEXT, true );
    add_integer( CFG_PREFIX "caching", DEFAULT_PTS_DELAY / 1000, NULL,
                CACHING_TEXT, CACHING_LONGTEXT, true );

    set_section( N_( "Tuner" ), NULL );
    add_integer( CFG_PREFIX "tuner", 0, NULL, TUNER_TEXT, TUNER_LONGTEXT,
                 true );
    add_integer( CFG_PREFIX "tuner-frequency", -1, NULL, FREQUENCY_TEXT,
                 FREQUENCY_LONGTEXT, true );
    add_integer( CFG_PREFIX "tuner-audio-mode", -1, NULL, TUNER_AUDIO_MODE_TEXT,
                 TUNER_AUDIO_MODE_LONGTEXT, true );
        change_integer_list( i_tuner_audio_modes_list,
                             psz_tuner_audio_modes_list_text, 0 );

    set_section( N_( "Controls" ),
                 N_( "v4l2 driver controls, if supported by your v4l2 driver." ) );
    add_bool( CFG_PREFIX "controls-reset", false, NULL, CTRL_RESET_TEXT,
              CTRL_RESET_LONGTEXT, true );
    add_integer( CFG_PREFIX "brightness", -1, NULL, BRIGHTNESS_TEXT,
                 BRIGHTNESS_LONGTEXT, true );
    add_integer( CFG_PREFIX "contrast", -1, NULL, CONTRAST_TEXT,
                 CONTRAST_LONGTEXT, true );
    add_integer( CFG_PREFIX "saturation", -1, NULL, SATURATION_TEXT,
                 SATURATION_LONGTEXT, true );
    add_integer( CFG_PREFIX "hue", -1, NULL, HUE_TEXT,
                 HUE_LONGTEXT, true );
    add_integer( CFG_PREFIX "black-level", -1, NULL, BLACKLEVEL_TEXT,
                 BLACKLEVEL_LONGTEXT, true );
    add_integer( CFG_PREFIX "auto-white-balance", -1, NULL,
                 AUTOWHITEBALANCE_TEXT, AUTOWHITEBALANCE_LONGTEXT, true );
    add_integer( CFG_PREFIX "do-white-balance", -1, NULL, DOWHITEBALANCE_TEXT,
                 DOWHITEBALANCE_LONGTEXT, true );
    add_integer( CFG_PREFIX "red-balance", -1, NULL, REDBALANCE_TEXT,
                 REDBALANCE_LONGTEXT, true );
    add_integer( CFG_PREFIX "blue-balance", -1, NULL, BLUEBALANCE_TEXT,
                 BLUEBALANCE_LONGTEXT, true );
    add_integer( CFG_PREFIX "gamma", -1, NULL, GAMMA_TEXT,
                 GAMMA_LONGTEXT, true );
    add_integer( CFG_PREFIX "exposure", -1, NULL, EXPOSURE_TEXT,
                 EXPOSURE_LONGTEXT, true );
    add_integer( CFG_PREFIX "autogain", -1, NULL, AUTOGAIN_TEXT,
                 AUTOGAIN_LONGTEXT, true );
    add_integer( CFG_PREFIX "gain", -1, NULL, GAIN_TEXT,
                 GAIN_LONGTEXT, true );
    add_integer( CFG_PREFIX "hflip", -1, NULL, HFLIP_TEXT,
                 HFLIP_LONGTEXT, true );
    add_integer( CFG_PREFIX "vflip", -1, NULL, VFLIP_TEXT,
                 VFLIP_LONGTEXT, true );
    add_integer( CFG_PREFIX "hcenter", -1, NULL, HCENTER_TEXT,
                 HCENTER_LONGTEXT, true );
    add_integer( CFG_PREFIX "vcenter", -1, NULL, VCENTER_TEXT,
                 VCENTER_LONGTEXT, true );
    add_integer( CFG_PREFIX "audio-volume", -1, NULL, AUDIO_VOLUME_TEXT,
                AUDIO_VOLUME_LONGTEXT, true );
    add_integer( CFG_PREFIX "audio-balance", -1, NULL, AUDIO_BALANCE_TEXT,
                AUDIO_BALANCE_LONGTEXT, true );
    add_bool( CFG_PREFIX "audio-mute", false, NULL, AUDIO_MUTE_TEXT,