demos/c_simple/v4l2_show.c

   1 /*****************************************************************************
   2  * This file is part of gfxprim library.                                     *
   3  *                                                                           *
   4  * Gfxprim is free software; you can redistribute it and/or                  *
   5  * modify it under the terms of the GNU Lesser General Public                *
   6  * License as published by the Free Software Foundation; either              *
   7  * version 2.1 of the License, or (at your option) any later version.        *
   8  *                                                                           *
   9  * Gfxprim is distributed in the hope that it will be useful,                *
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of            *
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU         *
  12  * Lesser General Public License for more details.                           *
  13  *                                                                           *
  14  * You should have received a copy of the GNU Lesser General Public          *
  15  * License along with gfxprim; if not, write to the Free Software            *
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor,                        *
  17  * Boston, MA  02110-1301  USA                                               *
  18  *                                                                           *
  19  * Copyright (C) 2009-2012 Cyril Hrubis <metan@ucw.cz>                       *
  20  *                                                                           *
  21  *****************************************************************************/
  22
  23  /*
  24
  25    Simple V4L2 grabber interactive example.
  26
  27   */
  28
  29 #include <errno.h>
  30 #include <string.h>
  31
  32 #include <GP.h>
  33 #include <backends/GP_X11.h>
  34
  35 int main(int argc, char *argv[])
  36 {
  37         GP_Backend *backend;
  38         GP_Grabber *grabber;
  39         const char *v4l2_device = "/dev/video0";
  40         unsigned int w = 320, h = 240;
  41         int mode = 0;
  42         int opt;
  43
  44         /* Turn on debug messages */
  45         //GP_SetDebugLevel(10);
  46
  47         while ((opt = getopt(argc, argv, "d:hH:W:l:")) != -1) {
  48                 switch (opt) {
  49                 case 'd':
  50                         v4l2_device = optarg;
  51                 break;
  52                 case 'W':
  53                         w = atoi(optarg);
  54                 break;
  55                 case 'H':
  56                         h = atoi(optarg);
  57                 break;
  58                 case 'l':
  59                         GP_SetDebugLevel(atoi(optarg));
  60                 break;
  61                 case 'h':
  62                         printf("Usage; %s opts\n", argv[0]);
  63                         printf("-d  v4l2 device name (default is '/dev/video0'\n"
  64                                "-W  output image width, default is 640\n"
  65                                "-H  output image height, default is 480\n"
  66                                "-l  sets GFXprim debug level (default is 0)\n"
  67                                "-h  prints this help\n");
  68                         return 0;
  69                 break;
  70                 default:
  71                         fprintf(stderr, "Invalid paramter '%c'\n", opt);
  72                         return 1;
  73                 }
  74         }
  75
  76         grabber = GP_GrabberV4L2Init(v4l2_device, w, h);
  77
  78         if (grabber == NULL) {
  79                 fprintf(stderr, "Failed to initalize grabber '%s': %s\n",
  80                         v4l2_device, strerror(errno));
  81                 return 1;
  82         }
  83
  84         backend = GP_BackendX11Init(NULL, 0, 0, grabber->frame->w,
  85                                     grabber->frame->h, "V4L2", 0);
  86
  87         if (backend == NULL) {
  88                 GP_GrabberExit(grabber);
  89                 return 1;
  90         }
  91
  92         if (GP_GrabberStart(grabber)) {
  93                 fprintf(stderr, "Failed to start grabber\n");
  94                 GP_BackendExit(backend);
  95                 GP_GrabberExit(grabber);
  96                 return 1;
  97         }
  98
  99         printf("Press SPACE to change mode and Q to exit.\n");
 100
 101         for (;;) {
 102                 if (GP_GrabberPoll(grabber) > 0) {
 103                         GP_Context *res, *img = grabber->frame;
 104
 105                         switch (mode) {
 106                         case 0:
 107                                 res = img;
 108                         break;
 109                         case 1:
 110                                 GP_FilterEdgePrewitt(img, &res, NULL, NULL);
 111                         break;
 112                         case 2:
 113                                 GP_FilterGaussianBlur(img, img, 1, 1, NULL);
 114                                 res = GP_FilterFloydSteinberg_RGB888_Alloc(img, GP_PIXEL_G2, NULL);
 115                         break;
 116                         }
 117
 118                         GP_Blit_Clipped(res, 0, 0, res->w, res->h, backend->context, 0, 0);
 119                         GP_BackendFlip(backend);
 120
 121                         if (mode)
 122                                 GP_ContextFree(res);
 123                 }
 124
 125                 usleep(1000);
 126
 127                 GP_BackendPoll(backend);
 128
 129                 /* Read and parse events */
 130                 GP_Event ev;
 131
 132                 while (GP_EventGet(&ev)) {
 133                         switch (ev.type) {
 134                         case GP_EV_KEY:
 135
 136                                 /* ignore key up events */
 137                                 if (!ev.code)
 138                                         continue;
 139
 140                                 switch (ev.val.key.key) {
 141                                 case GP_KEY_ESC:
 142                                 case GP_KEY_Q:
 143                                         GP_BackendExit(backend);
 144                                         GP_GrabberExit(grabber);
 145                                         return 0;
 146                                 break;
 147                                 case GP_KEY_SPACE:
 148
 149                                         mode++;
 150
 151                                         if (mode > 2)
 152                                                 mode = 0;
 153                                 break;
 154                                 }
 155                         }
 156                 }
 157         }
 158
 159         GP_BackendExit(backend);
 160
 161         return 0;
 162 }