This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / Documentation / video4linux / v4lgrab.c

diff --git a/Documentation/video4linux/v4lgrab.c b/Documentation/video4linux/v4lgrab.c
new file mode 100644 (file)
index 0000000..079b628
--- /dev/null
+++ b/Documentation/video4linux/v4lgrab.c
@@ -0,0 +1,192 @@
+/* Simple Video4Linux image grabber. */
+/*
+ *     Video4Linux Driver Test/Example Framegrabbing Program
+ *
+ *     Compile with:
+ *             gcc -s -Wall -Wstrict-prototypes v4lgrab.c -o v4lgrab
+ *      Use as:
+ *              v4lgrab >image.ppm
+ *
+ *     Copyright (C) 1998-05-03, Phil Blundell <philb@gnu.org>
+ *      Copied from http://www.tazenda.demon.co.uk/phil/vgrabber.c
+ *      with minor modifications (Dave Forrest, drf5n@virginia.edu).
+ *
+ */
+
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <sys/ioctl.h>
+#include <stdlib.h>
+
+#include <linux/types.h>
+#include <linux/videodev.h>
+
+#define FILE "/dev/video0"
+
+/* Stole this from tvset.c */
+
+#define READ_VIDEO_PIXEL(buf, format, depth, r, g, b)                   \
+{                                                                       \
+       switch (format)                                                 \
+       {                                                               \
+               case VIDEO_PALETTE_GREY:                                \
+                       switch (depth)                                  \
+                       {                                               \
+                               case 4:                                 \
+                               case 6:                                 \
+                               case 8:                                 \
+                                       (r) = (g) = (b) = (*buf++ << 8);\
+                                       break;                          \
+                                                                       \
+                               case 16:                                \
+                                       (r) = (g) = (b) =               \
+                                               *((unsigned short *) buf);      \
+                                       buf += 2;                       \
+                                       break;                          \
+                       }                                               \
+                       break;                                          \
+                                                                       \
+                                                                       \
+               case VIDEO_PALETTE_RGB565:                              \
+               {                                                       \
+                       unsigned short tmp = *(unsigned short *)buf;    \
+                       (r) = tmp&0xF800;                               \
+                       (g) = (tmp<<5)&0xFC00;                          \
+                       (b) = (tmp<<11)&0xF800;                         \
+                       buf += 2;                                       \
+               }                                                       \
+               break;                                                  \
+                                                                       \
+               case VIDEO_PALETTE_RGB555:                              \
+                       (r) = (buf[0]&0xF8)<<8;                         \
+                       (g) = ((buf[0] << 5 | buf[1] >> 3)&0xF8)<<8;    \
+                       (b) = ((buf[1] << 2 ) & 0xF8)<<8;               \
+                       buf += 2;                                       \
+                       break;                                          \
+                                                                       \
+               case VIDEO_PALETTE_RGB24:                               \
+                       (r) = buf[0] << 8; (g) = buf[1] << 8;           \
+                       (b) = buf[2] << 8;                              \
+                       buf += 3;                                       \
+                       break;                                          \
+                                                                       \
+               default:                                                \
+                       fprintf(stderr,                                 \
+                               "Format %d not yet supported\n",        \
+                               format);                                \
+       }                                                               \
+}
+
+int get_brightness_adj(unsigned char *image, long size, int *brightness) {
+  long i, tot = 0;
+  for (i=0;i<size*3;i++)
+    tot += image[i];
+  *brightness = (128 - tot/(size*3))/3;
+  return !((tot/(size*3)) >= 126 && (tot/(size*3)) <= 130);
+}
+
+int main(int argc, char ** argv)
+{
+  int fd = open(FILE, O_RDONLY), f;
+  struct video_capability cap;
+  struct video_window win;
+  struct video_picture vpic;
+
+  unsigned char *buffer, *src;
+  int bpp = 24, r, g, b;
+  unsigned int i, src_depth;
+
+  if (fd < 0) {
+    perror(FILE);
+    exit(1);
+  }
+
+  if (ioctl(fd, VIDIOCGCAP, &cap) < 0) {
+    perror("VIDIOGCAP");
+    fprintf(stderr, "(" FILE " not a video4linux device?)\n");
+    close(fd);
+    exit(1);
+  }
+
+  if (ioctl(fd, VIDIOCGWIN, &win) < 0) {
+    perror("VIDIOCGWIN");
+    close(fd);
+    exit(1);
+  }
+
+  if (ioctl(fd, VIDIOCGPICT, &vpic) < 0) {
+    perror("VIDIOCGPICT");
+    close(fd);
+    exit(1);
+  }
+
+  if (cap.type & VID_TYPE_MONOCHROME) {
+    vpic.depth=8;
+    vpic.palette=VIDEO_PALETTE_GREY;    /* 8bit grey */
+    if(ioctl(fd, VIDIOCSPICT, &vpic) < 0) {
+      vpic.depth=6;
+      if(ioctl(fd, VIDIOCSPICT, &vpic) < 0) {
+       vpic.depth=4;
+       if(ioctl(fd, VIDIOCSPICT, &vpic) < 0) {
+         fprintf(stderr, "Unable to find a supported capture format.\n");
+         close(fd);
+         exit(1);
+       }
+      }
+    }
+  } else {
+    vpic.depth=24;
+    vpic.palette=VIDEO_PALETTE_RGB24;
+
+    if(ioctl(fd, VIDIOCSPICT, &vpic) < 0) {
+      vpic.palette=VIDEO_PALETTE_RGB565;
+      vpic.depth=16;
+
+      if(ioctl(fd, VIDIOCSPICT, &vpic)==-1) {
+       vpic.palette=VIDEO_PALETTE_RGB555;
+       vpic.depth=15;
+
+       if(ioctl(fd, VIDIOCSPICT, &vpic)==-1) {
+         fprintf(stderr, "Unable to find a supported capture format.\n");
+         return -1;
+       }
+      }
+    }
+  }
+
+  buffer = malloc(win.width * win.height * bpp);
+  if (!buffer) {
+    fprintf(stderr, "Out of memory.\n");
+    exit(1);
+  }
+
+  do {
+    int newbright;
+    read(fd, buffer, win.width * win.height * bpp);
+    f = get_brightness_adj(buffer, win.width * win.height, &newbright);
+    if (f) {
+      vpic.brightness += (newbright << 8);
+      if(ioctl(fd, VIDIOCSPICT, &vpic)==-1) {
+       perror("VIDIOSPICT");
+       break;
+      }
+    }
+  } while (f);
+
+  fprintf(stdout, "P6\n%d %d 255\n", win.width, win.height);
+
+  src = buffer;
+
+  for (i = 0; i < win.width * win.height; i++) {
+    READ_VIDEO_PIXEL(src, vpic.palette, src_depth, r, g, b);
+    fputc(r>>8, stdout);
+    fputc(g>>8, stdout);
+    fputc(b>>8, stdout);
+  }
+
+  close(fd);
+  return 0;
+}