/*
 * Grab partial image from camera. Camera must be format 7
 *    (scalable image size) compatible.
 *
 * Written by Damien Douxchamps <ddouxchamps@users.sf.net>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <stdio.h>
#include <stdint.h>
#include <dc1394/dc1394.h>
#include <stdlib.h>
#include <time.h>
#include <inttypes.h>

#ifdef _WIN32
#define times 0**(int*)
struct tms {int a;};
#else
#include <sys/times.h>
#endif

int main(int argc, char *argv[])
{
    FILE* imagefile;
    dc1394camera_t *camera;
    int grab_n_frames = 10;
    struct tms tms_buf;
    clock_t start_time;
    float elapsed_time;
    int i;
    unsigned int min_bytes, max_bytes;
    unsigned int actual_bytes;
    uint64_t total_bytes = 0;
    unsigned int width, height;
    dc1394video_frame_t *frame=NULL;
    dc1394_t * d;
    dc1394camera_list_t * list;
    dc1394error_t err;

    d = dc1394_new ();
    if (!d)
        return 1;
    err=dc1394_camera_enumerate (d, &list);
    DC1394_ERR_RTN(err,"Failed to enumerate cameras");

    if (list->num == 0) {
        dc1394_log_error("No cameras found");
        return 1;
    }

    camera = dc1394_camera_new (d, list->ids[0].guid);
    if (!camera) {
        dc1394_log_error("Failed to initialize camera with guid %"PRIx64,
                list->ids[0].guid);
        return 1;
    }
    dc1394_camera_free_list (list);

    printf("Using camera with GUID %"PRIx64"\n", camera->guid);

    /*-----------------------------------------------------------------------
     *  setup capture for format 7
     *-----------------------------------------------------------------------*/

    dc1394_video_set_iso_speed(camera, DC1394_ISO_SPEED_400);
    dc1394_video_set_mode(camera, DC1394_VIDEO_MODE_FORMAT7_0);
    err = dc1394_format7_set_roi(camera, DC1394_VIDEO_MODE_FORMAT7_0,
                                 DC1394_COLOR_CODING_MONO8,
                                 DC1394_USE_MAX_AVAIL, // use max packet size
                                 0, 0, // left, top
                                 640, 480);  // width, height
    DC1394_ERR_RTN(err,"Unable to set Format7 mode 0.\nEdit the example file manually to fit your camera capabilities");

    err=dc1394_capture_setup(camera, 4, DC1394_CAPTURE_FLAGS_DEFAULT);
    DC1394_ERR_CLN_RTN(err, dc1394_camera_free(camera), "Error capturing");

    /*-----------------------------------------------------------------------
     *  print allowed and used packet size
     *-----------------------------------------------------------------------*/
    err=dc1394_format7_get_packet_parameters(camera, DC1394_VIDEO_MODE_FORMAT7_0, &min_bytes, &max_bytes);

    DC1394_ERR_RTN(err,"Packet para inq error");
    printf( "camera reports allowed packet size from %d - %d bytes\n", min_bytes, max_bytes);

    err=dc1394_format7_get_packet_size(camera, DC1394_VIDEO_MODE_FORMAT7_0, &actual_bytes);
    DC1394_ERR_RTN(err,"dc1394_format7_get_packet_size error");
    printf( "camera reports actual packet size = %d bytes\n", actual_bytes);

    err=dc1394_format7_get_total_bytes(camera, DC1394_VIDEO_MODE_FORMAT7_0, &total_bytes);
    DC1394_ERR_RTN(err,"dc1394_query_format7_total_bytes error");
    printf( "camera reports total bytes per frame = %"PRId64" bytes\n",
            total_bytes);

    /*-----------------------------------------------------------------------
     *  have the camera start sending us data
     *-----------------------------------------------------------------------*/
    err=dc1394_video_set_transmission(camera,DC1394_ON);
    if (err!=DC1394_SUCCESS) {
        dc1394_log_error("unable to start camera iso transmission");
        dc1394_capture_stop(camera);
        dc1394_camera_free(camera);
        exit(1);
    }

    /*-----------------------------------------------------------------------
     *  capture 10 frames and measure the time for this operation
     *-----------------------------------------------------------------------*/
    start_time = times(&tms_buf);

    for( i = 0; i < grab_n_frames; ++i) {
        /*-----------------------------------------------------------------------
         *  capture one frame
         *-----------------------------------------------------------------------*/
        err=dc1394_capture_dequeue(camera, DC1394_CAPTURE_POLICY_WAIT, &frame);
        if (err!=DC1394_SUCCESS) {
            dc1394_log_error("unable to capture");
            dc1394_capture_stop(camera);
            dc1394_camera_free(camera);
            exit(1);
        }

        /*---------------------------------------------------------------------
         *  output elapsed time
         *---------------------------------------------------------------------*/
        elapsed_time = (float)(times(&tms_buf) - start_time) / CLOCKS_PER_SEC;
        printf( "got frame %d. elapsed time: %g sec ==> %g frames/second\n",
                i, elapsed_time, (float)i / elapsed_time);

        // release buffer
        dc1394_capture_enqueue(camera,frame);
    }

    /*-----------------------------------------------------------------------
     *  stop data transmission
     *-----------------------------------------------------------------------*/
    err=dc1394_video_set_transmission(camera,DC1394_OFF);
    DC1394_ERR_RTN(err,"couldn't stop the camera?");

    /*-----------------------------------------------------------------------
     *  save last image as Part.pgm
     *-----------------------------------------------------------------------*/
    imagefile=fopen("Part.pgm","wb");

    dc1394_get_image_size_from_video_mode(camera, DC1394_VIDEO_MODE_FORMAT7_0, &width, &height);
    fprintf(imagefile,"P5\n%u %u\n255\n", width, height);
    fwrite(frame->image, 1, height * width, imagefile);
    fclose(imagefile);
    printf("wrote: Part.pgm\n");

    /*-----------------------------------------------------------------------
     *  close camera, cleanup
     *-----------------------------------------------------------------------*/
    dc1394_capture_stop(camera);
    dc1394_video_set_transmission(camera, DC1394_OFF);
    dc1394_camera_free(camera);
    dc1394_free (d);
    return 0;
}