video_capture.c

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/*
 * 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/>.
 *
 */

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <time.h>

#include "modules/computer_vision/video_capture.h"
#include "modules/computer_vision/cv.h"

#include "lib/encoding/jpeg.h"

// Note: this define is set automatically when the video_exif module is included,
// and exposes functions to write data in the image exif headers.
#if JPEG_WITH_EXIF_HEADER
#include "lib/exif/exif_module.h"
#endif

#ifndef VIDEO_CAPTURE_PATH
#define VIDEO_CAPTURE_PATH /data/video/images
#endif

#ifndef VIDEO_CAPTURE_JPEG_QUALITY
#define VIDEO_CAPTURE_JPEG_QUALITY 99
#endif

#ifndef VIDEO_CAPTURE_FPS
#define VIDEO_CAPTURE_FPS 0       
#endif
PRINT_CONFIG_VAR(VIDEO_CAPTURE_FPS)

// Module settings
bool video_capture_take_shot = false; // Capture single images
bool video_capture_record_video = false; // Capture video
int video_capture_index = 0;

// Save directory
static char save_dir[256];

// Forward function declarations
struct image_t *video_capture_func(struct image_t *img);
void video_capture_save(struct image_t *img);


void video_capture_init(void)
{
  // Create images directory with timestamp
  struct timeval tv;
  struct tm *tm;
  gettimeofday(&tv, NULL);
  tm = localtime(&tv.tv_sec);

  sprintf(save_dir, "%s/%04d%02d%02d-%02d%02d%02d", STRINGIFY(VIDEO_CAPTURE_PATH),
      tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,
      tm->tm_hour, tm->tm_min, tm->tm_sec);
  // Folder creation delayed until capture starts, see video_capture_save.
  // This prevents empty folders if nothing is actually recorded.

  // Add function to computer vision pipeline
  cv_add_to_device(&VIDEO_CAPTURE_CAMERA, video_capture_func, VIDEO_CAPTURE_FPS);
}


struct image_t *video_capture_func(struct image_t *img)
{
  // If take_shot bool is set, save the image
  if (video_capture_take_shot || video_capture_record_video) {
    video_capture_save(img);
    video_capture_take_shot = false;
  }

  // No modification to image
  return NULL;
}


void video_capture_shoot(void)
{
  // Set take_shot bool to true
  video_capture_take_shot = true;
}

void video_capture_start_capture(void) {
  video_capture_record_video = true;
}

void video_capture_stop_capture(void) {
  video_capture_record_video = false;
}

void video_capture_save(struct image_t *img)
{
  // Create output folder if necessary
  if (access(save_dir, F_OK)) {
    char save_dir_cmd[256];
    sprintf(save_dir_cmd, "mkdir -p %s", save_dir);
    if (system(save_dir_cmd) != 0) {
      printf("[video_capture] Could not create images directory %s.\n", save_dir);
      return;
    }
  }

  // Declare storage for image location
  char save_name[256];

  // Generate image filename from image timestamp
  sprintf(save_name, "%s/%u.jpg", save_dir, img->pprz_ts);
  printf("[video_capture] Saving image to %s.\n", save_name);

  // Create jpg image from raw frame
  struct image_t img_jpeg;
  image_create(&img_jpeg, img->w, img->h, IMAGE_JPEG);
  jpeg_encode_image(img, &img_jpeg, VIDEO_CAPTURE_JPEG_QUALITY, 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
  // Open file
  FILE *fp = fopen(save_name, "w");
  if (fp == NULL) {
    printf("[video_capture] Could not write shot %s.\n", save_name);
    return;
  }

  // Save it to the file and close it
  fwrite(img_jpeg.buf, sizeof(uint8_t), img_jpeg.buf_size, fp);
  fclose(fp);
#endif

  // Free image
  image_free(&img_jpeg);
}