// Get a frame from the camera device
void getFrames(int noFrames, int minNoFrames, int* fd, int* imgCaptureType,
int cqual, int fps, int bufferSize)
{
struct v4l2_buffer buf;
struct buffer* bufs;
struct v4l2_requestbuffers reqbuf = getReqBufs(noFrames, minNoFrames, fd);
unsigned int n_buffers, i, ctr = 0;
bool started = FALSE, streamOn = false;
struct lstnode* cNode = allocate(bufferSize);
pthread_mutex_t* mutex = (pthread_mutex_t*)malloc(sizeof(pthread_mutex_t));
pthread_mutex_init(mutex, NULL);
struct imgDetails det = getFrameFormat(fd); // get video format details
bufs = (struct buffer*)calloc(reqbuf.count, sizeof(*bufs)); // alloc buffers
// If allocation fails
if (bufs == NULL) exitWithError("Could not allocate buffers.");
// Map the memory in kernel space to user space to access video efficiently
for (n_buffers = 0; n_buffers < reqbuf.count; n_buffers++)
{
mapBuffer(reqbuf, n_buffers, buf, bufs, fd);
}
// Queue the request struct to v4l2 to retrieve the video data mem location
for(i = 0; i < reqbuf.count; i++) queueBuffer(i, buf, fd);
streamOn = turnOnCamera(fd, streamOn, imgCaptureType); // turn on camera
while(true) //forever
{
if(!started) // if the write data thread has not yet been started
{
started = TRUE;
createThread(cNode, mutex);
}
for(i = 0; i < reqbuf.count; i++) // for each frame returned
{
usleep(fps); // maintain steady frame rate
pthread_mutex_lock(mutex); // lock pointers
createImage(buf, bufs, i, cNode, fd, det, cqual);
cNode = cNode->next; // work with the next node in the list
printf("|%d|\n", ctr++);
pthread_mutex_unlock(mutex); // release locks
queueBuffer(i, buf, fd); // queue up a new buffer
}
}
for (i = 0; i < reqbuf.count; ++i) // unmap memory
{
munmap(bufs[i].start, bufs[i].length);
}
free(mutex);
free(cNode);
free(bufs);
}
int main()
{
Initialize();
_delay_ms(100);
setUpCamera();
_delay_ms(100);
//Set current Mode (temporary)
nextMode = CAPTURE;
sei ();
while(1)
{
switch (nextMode)
{
case IDLE:
///Don't do anything, just chill
break;
case CAPTURE:
///Turn on camera if necessary
if (cameraOn == 0)
{
turnOnCamera();
}
break;
case SENDING:
//SEND DATA CALL HERE
sendLineBuffer();
break;
case STEPPING:
//Enable stepper motor timer here
break;
}
}
}
