Merge pull request #1333 from paparazzi/board_knows_camera_settings

- put camera settings, format and filters into board files
- add debayer filter in video_thread to use it for bebop front cam
- simply define VIDEO_THREAD_CAMERA to bottom_camera or front_camera on ARDrone2 or Bebop
- runtime adjustable fps

conf/airframes/BR/bebop_default.xml

@@ -32,11 +32,8 @@
       <define name="FILE_LOGGER_PATH" value="/data/ftp/internal_000"/>
     </load-->
     <load name="video_thread.xml">
+      <define name="VIDEO_THREAD_CAMERA" value="bottom_camera"/>
       <define name="VIDEO_THREAD_FPS" value="4"/>
-      <define name="VIDEO_THREAD_DEVICE" value="/dev/video0"/>
-      <define name="VIDEO_THREAD_SUBDEV" value="/dev/v4l-subdev0"/>
-      <define name="VIDEO_THREAD_DEVICE_SIZE" value="640,480"/>
-      <define name="VIDEO_THREAD_DEVICE_BUFFERS" value="60"/>
       <define name="VIDEO_THREAD_SHOT_PATH" value="/data/ftp/internal_000/images"/>
     </load>
     <load name="video_rtp_stream.xml">

conf/airframes/BR/bebop_indi.xml

@@ -38,10 +38,7 @@
     </load-->
     <load name="video_thread.xml">
       <define name="VIDEO_THREAD_FPS" value="4"/>
-      <define name="VIDEO_THREAD_DEVICE" value="/dev/video0"/>
-      <define name="VIDEO_THREAD_SUBDEV" value="/dev/v4l-subdev0"/>
-      <define name="VIDEO_THREAD_DEVICE_SIZE" value="640,480"/>
-      <define name="VIDEO_THREAD_DEVICE_BUFFERS" value="60"/>
+      <define name="VIDEO_THREAD_CAMERA" value="bottom_camera"/>
       <define name="VIDEO_THREAD_SHOT_PATH" value="/data/ftp/internal_000/images"/>
     </load>
     <load name="cv_blob_locator.xml"/>

conf/airframes/BR/bebop_indi_frog.xml

@@ -37,11 +37,8 @@
       <define name="FILE_LOGGER_PATH" value="/data/ftp/internal_000"/>
     </load-->
     <load name="video_thread.xml">
+      <define name="VIDEO_THREAD_CAMERA" value="bottom_camera"/>
       <define name="VIDEO_THREAD_FPS" value="4"/>
-      <define name="VIDEO_THREAD_DEVICE" value="/dev/video0"/>
-      <define name="VIDEO_THREAD_SUBDEV" value="/dev/v4l-subdev0"/>
-      <define name="VIDEO_THREAD_DEVICE_SIZE" value="640,480"/>
-      <define name="VIDEO_THREAD_DEVICE_BUFFERS" value="60"/>
       <define name="VIDEO_THREAD_SHOT_PATH" value="/data/ftp/internal_000/images"/>
     </load>
     <load name="video_rtp_stream.xml">

conf/airframes/BR/bebop_indi_frog_flip.xml

@@ -37,11 +37,8 @@
       <define name="FILE_LOGGER_PATH" value="/data/ftp/internal_000"/>
     </load-->
     <load name="video_thread.xml">
+      <define name="VIDEO_THREAD_CAMERA" value="bottom_camera"/>
       <define name="VIDEO_THREAD_FPS" value="4"/>
-      <define name="VIDEO_THREAD_DEVICE" value="/dev/video0"/>
-      <define name="VIDEO_THREAD_SUBDEV" value="/dev/v4l-subdev0"/>
-      <define name="VIDEO_THREAD_DEVICE_SIZE" value="640,480"/>
-      <define name="VIDEO_THREAD_DEVICE_BUFFERS" value="60"/>
       <define name="VIDEO_THREAD_SHOT_PATH" value="/data/ftp/internal_000/images"/>
     </load>
     <load name="video_rtp_stream.xml">

conf/airframes/CDW/bebop.xml

@@ -38,10 +38,7 @@
     </load-->
     <load name="video_thread.xml">
       <define name="VIDEO_THREAD_FPS" value="4"/>
-      <define name="VIDEO_THREAD_DEVICE" value="/dev/video0"/>
-      <define name="VIDEO_THREAD_SUBDEV" value="/dev/v4l-subdev0"/>
-      <define name="VIDEO_THREAD_DEVICE_SIZE" value="640,480"/>
-      <define name="VIDEO_THREAD_DEVICE_BUFFERS" value="60"/>
+      <define name="VIDEO_THREAD_CAMERA" value="bottom_camera"/>
       <define name="VIDEO_THREAD_SHOT_PATH" value="/data/ftp/internal_000/images"/>
     </load>
     <load name="cv_blob_locator.xml"/>

conf/airframes/ENAC/quadrotor/ard2_base_digit.xml

@@ -36,7 +36,9 @@
     <load name="agl_dist.xml">
       <define name="USE_SONAR"/>
     </load>
-    <load name="video_thread.xml"/>
+    <load name="video_thread.xml">
+      <define name="VIDEO_THREAD_CAMERA" value="front_camera"/>
+    </load>
     <load name="video_rtp_stream.xml">
       <configure name="VIEWVIDEO_USE_NC" value="TRUE"/>
     </load>

conf/airframes/ENAC/quadrotor/ard2_base_vision.xml

@@ -36,7 +36,9 @@
     <load name="agl_dist.xml">
       <define name="USE_SONAR"/>
     </load>
-    <load name="video_thread.xml"/>
+    <load name="video_thread.xml">
+      <define name="VIDEO_THREAD_CAMERA" value="front_camera"/>
+    </load>
     <load name="video_rtp_stream.xml">
       <define name="VIDEO_SOCK_OUT_OFFSET" value="$(AC_ID)"/>
       <define name="VIDEO_DOWNSIZE_FACTOR" value="2"/>

conf/airframes/examples/ardrone2.xml

@@ -32,7 +32,11 @@
     <load name="air_data.xml"/>
     <load name="geo_mag.xml"/>
     <!--load name="logger_file.xml"/-->
-    <!--load name="video_thread.xml"/-->
+    <!--
+    <load name="video_thread.xml">
+        <define name="VIDEO_THREAD_CAMERA" value="front_camera"/>
+    </load>
+    -->
     <!--load name="video_rtp_stream.xml"/-->
   </modules>
 

conf/airframes/examples/bebop.xml

@@ -33,10 +33,7 @@
     </load-->
     <load name="video_thread.xml">
       <define name="VIDEO_THREAD_FPS" value="4"/>
-      <define name="VIDEO_THREAD_DEVICE" value="/dev/video0"/>
-      <define name="VIDEO_THREAD_SUBDEV" value="/dev/v4l-subdev0"/>
-      <define name="VIDEO_THREAD_DEVICE_SIZE" value="640,480"/>
-      <define name="VIDEO_THREAD_DEVICE_BUFFERS" value="60"/>
+      <define name="VIDEO_THREAD_CAMERA" value="bottom_camera"/>
       <define name="VIDEO_THREAD_SHOT_PATH" value="/data/ftp/internal_000/images"/>
     </load>
     <load name="video_rtp_stream.xml">

conf/modules/video_thread.xml

@@ -3,16 +3,20 @@
 <module name="video_thread" dir="computer_vision">
   <doc>
     <description>
-      Video streaming for Linux devices
+      Read video in a thread.
+      Only for Linux devices.
+      To be used in other modules for further processing (e.g. opticflow, QR code, streaming).
 
-      - Sends a RTP/UDP stream of the camera
       - Possibility to save an image(shot) on the internal memory (JPEG, full size, best quality)
     </description>
-    <define name="VIDEO_THREAD_DEVICE" value="/dev/video1" description="The video device to capture from"/>
-    <define name="VIDEO_THREAD_DEVICE_SIZE" value="1280,720" description="Video capture size (width, height)"/>
-    <define name="VIDEO_THREAD_DEVICE_BUFFERS" value="10" description="Amount of V4L2 image buffers"/>
+    <define name="VIDEO_THREAD_CAMERA" value="bottom_camera|front_camera" description="which camera video config to use"/>
     <define name="VIDEO_THREAD_FPS" value="4" description="Video stream frame rate"/>
     <define name="VIDEO_THREAD_SHOT_PATH" value="/data/video/images" description="Path where the images should be saved"/>
+    <define name="VIDEO_THREAD_DEVICE" value="/dev/video1" description="The video device to capture from (only if VIDEO_THREAD_CAMERA is not defined)"/>
+    <define name="VIDEO_THREAD_DEVICE_VIDEO_WIDTH" value="1280" description="Video capture width (only if VIDEO_THREAD_CAMERA is not defined)"/>
+    <define name="VIDEO_THREAD_DEVICE_VIDEO_HEIGHT" value="720" description="Video capture height (only if VIDEO_THREAD_CAMERA is not defined)"/>
+    <define name="VIDEO_THREAD_DEVICE_BUFFERS" value="10" description="Amount of V4L2 image buffers (only if VIDEO_THREAD_CAMERA is not defined)"/>
+
   </doc>
   <settings>
     <dl_settings>
@@ -20,6 +24,7 @@
         <dl_setting var="video_thread.take_shot" min="0" step="1" max="1" shortname="take_shot" module="computer_vision/video_thread" handler="take_shot">
           <strip_button name="Shoot" icon="digital-camera.png" value="1" group="video"/>
         </dl_setting>
+        <dl_setting var="video_thread.fps" min="1" step="1" max="25" shortname="fps" module="computer_vision/video_thread" param="VIDEO_THREAD_FPS"/>
       </dl_settings>
     </dl_settings>
   </settings>

sw/airborne/arch/linux/mcu_periph/sys_time_arch.h

@@ -57,4 +57,17 @@ static inline void sys_time_usleep(uint32_t us)
   usleep(us);
 }
 
+/** elapsed time in microsecs between two timespecs */
+static inline unsigned int sys_time_elapsed_us(struct timespec *prev, struct timespec *now)
+{
+  time_t d_sec = now->tv_sec - prev->tv_sec;
+  long d_nsec = now->tv_nsec - prev->tv_nsec;
+  /* wrap if negative nanoseconds */
+  if (d_nsec < 0) {
+    d_sec -= 1;
+    d_nsec += 1000000000L;
+  }
+  return d_sec * 1000000 + d_nsec / 1000;
+}
+
 #endif /* SYS_TIME_ARCH_H */

sw/airborne/boards/ardrone/board.c

@@ -34,6 +34,29 @@
 #warning No battery voltage measurement available! Please add <load name="bat_voltage_ardrone2.xml"/> to your modules.
 #endif
 
+#include "peripherals/video_device.h"
+
+struct video_config_t front_camera = {
+  .w = 1280,
+  .h = 720,
+  .dev_name = "/dev/video1",
+  .subdev_name = NULL,
+  .format = V4L2_PIX_FMT_UYVY,
+  .buf_cnt = 10,
+  .filters = 0
+};
+
+struct video_config_t bottom_camera = {
+  .w = 320,
+  .h = 240,
+  .dev_name = "/dev/video2",
+  .subdev_name = NULL,
+  .format = V4L2_PIX_FMT_UYVY,
+  .buf_cnt = 10,
+  .filters = 0
+};
+
+
 void board_init(void)
 {
   // First we try to kill the program.elf and its respawner if it is running

sw/airborne/boards/ardrone2.h

@@ -3,10 +3,16 @@
 
 #define BOARD_ARDRONE2
 
+#include "peripherals/video_device.h"
+
 #ifndef UART1_DEV
 #define UART1_DEV /dev/ttyUSB0
 #endif
 
+/* Cameras */
+extern struct video_config_t bottom_camera;
+extern struct video_config_t front_camera;
+
 /* Default actuators driver */
 #define DEFAULT_ACTUATORS "boards/ardrone/actuators.h"
 #define ActuatorDefaultSet(_x,_y) ActuatorArdroneSet(_x,_y)

sw/airborne/boards/bebop.h

@@ -25,6 +25,8 @@
 
 #define BOARD_BEBOP
 
+#include "peripherals/video_device.h"
+
 /** uart connected to GPS internally */
 #define UART1_DEV /dev/ttyPA1
 
@@ -34,6 +36,9 @@
 #define ActuatorsDefaultInit() ActuatorsBebopInit()
 #define ActuatorsDefaultCommit() ActuatorsBebopCommit()
 
+/* Cameras */
+extern struct video_config_t bottom_camera;
+extern struct video_config_t front_camera;
 
 /* by default activate onboard baro */
 #ifndef USE_BARO_BOARD

sw/airborne/boards/bebop/video.c

@@ -37,6 +37,28 @@
 #include <linux/i2c-dev.h>
 #include <linux/types.h>
 
+#include "boards/bebop.h"
+
+struct video_config_t bottom_camera = {
+  .w = 640,
+  .h = 480,
+  .dev_name = "/dev/video0",
+  .subdev_name = NULL,
+  .format = V4L2_PIX_FMT_UYVY,
+  .buf_cnt = 60,
+  .filters = 0
+};
+
+struct video_config_t front_camera = {
+  .w = 1408,
+  .h = 2112,
+  .dev_name = "/dev/video1",
+  .subdev_name = "/dev/v4l-subdev1",
+  .format = V4L2_PIX_FMT_SGBRG10,
+  .buf_cnt = 10,
+  .filters = VIDEO_FILTER_DEBAYER
+};
+
 static bool_t write_reg(int fd, char *addr_val, uint8_t cnt)
 {
   char resp[cnt - 2];

sw/airborne/modules/computer_vision/lib/v4l/v4l2.h

@@ -33,7 +33,7 @@
 #include <sys/time.h>
 
 #include "std.h"
-#include "lib/vision/image.h"
+#include "modules/computer_vision/lib/vision/image.h"
 
 #define V4L2_IMG_NONE 255  ///< There currently no image available
 

sw/airborne/modules/computer_vision/lib/vision/image.c

@@ -62,7 +62,10 @@ void image_create(struct image_t *img, uint16_t width, uint16_t height, enum ima
  */
 void image_free(struct image_t *img)
 {
-  free(img->buf);
+  if (img->buf != NULL) {
+    free(img->buf);
+    img->buf = NULL;
+  }
 }
 
 /**

sw/airborne/modules/computer_vision/video_thread.c

@@ -37,7 +37,14 @@
 // Video
 #include "lib/v4l/v4l2.h"
 #include "lib/vision/image.h"
+#include "lib/vision/bayern.h"
 #include "lib/encoding/jpeg.h"
+#include "peripherals/video_device.h"
+
+#include "mcu_periph/sys_time.h"
+
+// include board for bottom_camera and front_camera on ARDrone2 and Bebop
+#include BOARD_CONFIG
 
 #if JPEG_WITH_EXIF_HEADER
 #include "lib/exif/exif_module.h"
@@ -47,25 +54,32 @@
 #include <pthread.h>
 #include "rt_priority.h"
 
-// The video device
-#ifndef VIDEO_THREAD_DEVICE
-#define VIDEO_THREAD_DEVICE /dev/video1
-#endif
-PRINT_CONFIG_VAR(VIDEO_THREAD_DEVICE)
-
-// The video device size (width, height)
-#ifndef VIDEO_THREAD_DEVICE_SIZE
-#define VIDEO_THREAD_DEVICE_SIZE 1280,720
-#endif
-#define __SIZE_HELPER(x, y) #x", "#y
-#define _SIZE_HELPER(x) __SIZE_HELPER(x)
-PRINT_CONFIG_MSG("VIDEO_THREAD_DEVICE_SIZE = " _SIZE_HELPER(VIDEO_THREAD_DEVICE_SIZE))
-
+/// The camera video config (usually bottom_camera or front_camera)
+#ifndef VIDEO_THREAD_CAMERA
+#warning "Are you sure you don't want to use the bottom_camera or front_camera?"
 // The video device buffers (the amount of V4L2 buffers)
 #ifndef VIDEO_THREAD_DEVICE_BUFFERS
 #define VIDEO_THREAD_DEVICE_BUFFERS 10
 #endif
 PRINT_CONFIG_VAR(VIDEO_THREAD_DEVICE_BUFFERS)
+#ifndef VIDEO_THREAD_SUBDEV
+#define VIDEO_THREAD_SUBDEV NULL
+#endif
+#ifndef VIDEO_THREAD_FILTERS
+#define VIDEO_THREAD_FILTERS 0
+#endif
+struct video_config_t custom_camera = {
+  .w = VIDEO_THREAD_VIDEO_WIDTH,
+  .h = VIDEO_THREAD_VIDEO_HEIGHT,
+  .dev_name = STRINGIFY(VIDEO_THREAD_DEVICE),
+  .subdev_name = VIDEO_THREAD_SUBDEV,
+  .buf_cnt = VIDEO_THREAD_DEVICE_BUFFERS,
+  .filters = VIDEO_THREAD_FILTERS
+};
+#define VIDEO_THREAD_CAMERA custom_camera
+#endif
+PRINT_CONFIG_VAR(VIDEO_THREAD_CAMERA)
+
 
 // Frames Per Seconds
 #ifndef VIDEO_THREAD_FPS
@@ -91,12 +105,61 @@ struct video_thread_t video_thread = {
   .shot_number = 0
 };
 
+static void video_thread_save_shot(struct image_t *img, struct image_t *img_jpeg)
+{
+
+  // Search for a file where we can write to
+  char save_name[128];
+  for (; video_thread.shot_number < 99999; video_thread.shot_number++) {
+    sprintf(save_name, "%s/img_%05d.jpg", STRINGIFY(VIDEO_THREAD_SHOT_PATH), video_thread.shot_number);
+    // Check if file exists or not
+    if (access(save_name, F_OK) == -1) {
+
+      // Create a high quality image (99% JPEG encoded)
+      jpeg_encode_image(img, img_jpeg, 99, TRUE);
+
+#if JPEG_WITH_EXIF_HEADER
+      write_exif_jpeg(save_name, img_jpeg->buf, img_jpeg->buf_size, img_jpeg->w, img_jpeg->h);
+#else
+      FILE *fp = fopen(save_name, "w");
+      if (fp == NULL) {
+        printf("[video_thread-thread] Could not write shot %s.\n", save_name);
+      } else {
+        // Save it to the file and close it
+        fwrite(img_jpeg->buf, sizeof(uint8_t), img_jpeg->buf_size, fp);
+        fclose(fp);
+      }
+#endif
+
+      // We don't need to seek for a next index anymore
+      break;
+    }
+  }
+}
+
+
 /**
  * Handles all the video streaming and saving of the image shots
  * This is a sepereate thread, so it needs to be thread safe!
  */
-static void *video_thread_function(void *data __attribute__((unused)))
+static void *video_thread_function(void *data)
 {
+  struct video_config_t *vid = (struct video_config_t *)&(VIDEO_THREAD_CAMERA);
+
+  struct image_t img_jpeg;
+  struct image_t img_color;
+
+  // create the images
+  if (vid->filters) {
+    // fixme: don't hardcode size, works for bebop front camera for now
+#define IMG_FLT_SIZE 272
+    image_create(&img_color, IMG_FLT_SIZE, IMG_FLT_SIZE, IMAGE_YUV422);
+    image_create(&img_jpeg, IMG_FLT_SIZE, IMG_FLT_SIZE, IMAGE_JPEG);
+  }
+  else {
+    image_create(&img_jpeg, vid->w, vid->h, IMAGE_JPEG);
+  }
+
   // Start the streaming of the V4L2 device
   if (!v4l2_start_capture(video_thread.dev)) {
     printf("[video_thread-thread] Could not start capture of %s.\n", video_thread.dev->name);
@@ -107,67 +170,57 @@ static void *video_thread_function(void *data __attribute__((unused)))
   set_nice_level(10);
 
   // Initialize timing
-  uint32_t microsleep = (uint32_t)(1000000. / (float)video_thread.fps);
-  struct timeval last_time;
-  gettimeofday(&last_time, NULL);
+  struct timespec time_now;
+  struct timespec time_prev;
+  clock_gettime(CLOCK_MONOTONIC, &time_prev);
 
   // Start streaming
   video_thread.is_running = TRUE;
   while (video_thread.is_running) {
-    // compute usleep to have a more stable frame rate
-    struct timeval vision_thread_sleep_time;
-    gettimeofday(&vision_thread_sleep_time, NULL);
-    int dt = (int)(vision_thread_sleep_time.tv_sec - last_time.tv_sec) * 1000000 +
-             (int)(vision_thread_sleep_time.tv_usec - last_time.tv_usec);
-    if (dt < microsleep) { usleep(microsleep - dt); }
-    last_time = vision_thread_sleep_time;
+
+    // get time in us since last run
+    clock_gettime(CLOCK_MONOTONIC, &time_now);
+    unsigned int dt_us = sys_time_elapsed_us(&time_prev, &time_now);
+    time_prev = time_now;
+
+    // sleep remaining time to limit to specified fps
+    uint32_t fps_period_us = (uint32_t)(1000000. / (float)video_thread.fps);
+    if (dt_us < fps_period_us) {
+      usleep(fps_period_us - dt_us);
+    }
 
     // Wait for a new frame (blocking)
     struct image_t img;
     v4l2_image_get(video_thread.dev, &img);
 
+    // pointer to the final image to pass for saving and further processing
+    struct image_t *img_final = &img;
+
+    // run selected filters
+    if (vid->filters) {
+      if (vid->filters & VIDEO_FILTER_DEBAYER) {
+        BayernToYUV(&img, &img_color, 0, 0);
+      }
+      // use color image for further processing
+      img_final = &img_color;
+    }
+
     // Check if we need to take a shot
     if (video_thread.take_shot) {
-      // Create a high quality image (99% JPEG encoded)
-      struct image_t jpeg_hr;
-      image_create(&jpeg_hr, img.w, img.h, IMAGE_JPEG);
-      jpeg_encode_image(&img, &jpeg_hr, 99, TRUE);
-
-      // Search for a file where we can write to
-      char save_name[128];
-      for (; video_thread.shot_number < 99999; video_thread.shot_number++) {
-        sprintf(save_name, "%s/img_%05d.jpg", STRINGIFY(VIDEO_THREAD_SHOT_PATH), video_thread.shot_number);
-        // Check if file exists or not
-        if (access(save_name, F_OK) == -1) {
-#if JPEG_WITH_EXIF_HEADER
-          write_exif_jpeg(save_name, jpeg_hr.buf, jpeg_hr.buf_size, img.w, img.h);
-#else
-          FILE *fp = fopen(save_name, "w");
-          if (fp == NULL) {
-            printf("[video_thread-thread] Could not write shot %s.\n", save_name);
-          } else {
-            // Save it to the file and close it
-            fwrite(jpeg_hr.buf, sizeof(uint8_t), jpeg_hr.buf_size, fp);
-            fclose(fp);
-          }
-#endif
-          // We don't need to seek for a next index anymore
-          break;
-        }
-      }
-
-      // We finished the shot
-      image_free(&jpeg_hr);
+      video_thread_save_shot(img_final, &img_jpeg);
       video_thread.take_shot = FALSE;
     }
 
     // Run processing if required
-    cv_run(&img);
+    cv_run(img_final);
 
     // Free the image
     v4l2_image_free(video_thread.dev, &img);
   }
 
+  image_free(&img_jpeg);
+  image_free(&img_color);
+
   return 0;
 }
 
@@ -176,21 +229,21 @@ static void *video_thread_function(void *data __attribute__((unused)))
  */
 void video_thread_init(void)
 {
-#ifdef VIDEO_THREAD_SUBDEV
-  PRINT_CONFIG_MSG("[video_thread] Configuring a subdevice!")
-  PRINT_CONFIG_VAR(VIDEO_THREAD_SUBDEV)
+  struct video_config_t *vid = (struct video_config_t *)&(VIDEO_THREAD_CAMERA);
 
-  // Initialize the V4L2 subdevice (TODO: fix hardcoded path, which and code)
-  if (!v4l2_init_subdev(STRINGIFY(VIDEO_THREAD_SUBDEV), 0, 1, V4L2_MBUS_FMT_UYVY8_2X8, VIDEO_THREAD_DEVICE_SIZE)) {
-    printf("[video_thread] Could not initialize the %s subdevice.\n", STRINGIFY(VIDEO_THREAD_SUBDEV));
-    return;
+  // Initialize the V4L2 subdevice if needed
+  if (vid->subdev_name != NULL) {
+    // FIXME! add subdev format to config, only needed on bebop front camera so far
+    if (!v4l2_init_subdev(vid->subdev_name, 0, 0, V4L2_MBUS_FMT_SGBRG10_1X10, vid->w, vid->h)) {
+      printf("[video_thread] Could not initialize the %s subdevice.\n", vid->subdev_name);
+      return;
+    }
   }
-#endif
 
   // Initialize the V4L2 device
-  video_thread.dev = v4l2_init(STRINGIFY(VIDEO_THREAD_DEVICE), VIDEO_THREAD_DEVICE_SIZE, VIDEO_THREAD_DEVICE_BUFFERS,  V4L2_PIX_FMT_UYVY);
+  video_thread.dev = v4l2_init(vid->dev_name, vid->w, vid->h, vid->buf_cnt, vid->format);
   if (video_thread.dev == NULL) {
-    printf("[video_thread] Could not initialize the %s V4L2 device.\n", STRINGIFY(VIDEO_THREAD_DEVICE));
+    printf("[video_thread] Could not initialize the %s V4L2 device.\n", vid->dev_name);
     return;
   }
 
@@ -215,7 +268,7 @@ void video_thread_start(void)
 
   // Start the streaming thread
   pthread_t tid;
-  if (pthread_create(&tid, NULL, video_thread_function, NULL) != 0) {
+  if (pthread_create(&tid, NULL, video_thread_function, (void*)(&VIDEO_THREAD_CAMERA)) != 0) {
     printf("[vievideo] Could not create streaming thread.\n");
     return;
   }

sw/airborne/peripherals/video_device.h

@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2015
+ *
+ * This file is part of Paparazzi.
+ *
+ * Paparazzi 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, or (at your option)
+ * any later version.
+ *
+ * Paparazzi 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 paparazzi; see the file COPYING.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * @file peripherals/video_device.h
+ * @brief v4l2 video device settings interface
+ * Works on Linux platforms
+ */
+
+#ifndef VIDEO_DEVICE_H
+#define VIDEO_DEVICE_H
+
+#include "std.h"
+#include "modules/computer_vision/lib/v4l/v4l2.h"
+
+#define VIDEO_FILTER_DEBAYER 0x01
+
+/** V4L2 device settings */
+struct video_config_t {
+  int w;              ///< Width
+  int h;              ///< Height
+  char* dev_name;     ///< path to device
+  char* subdev_name;  ///< path to sub device
+  uint32_t format;    ///< Video format
+  uint8_t buf_cnt;    ///< Amount of V4L2 video device buffers
+  uint8_t filters;    ///< filters to use (bitfield with VIDEO_FILTER_x)
+};
+
+
+#endif /* VIDEO_DEVICE_H */