mirror of
https://github.com/hyperion-project/hyperion.ng.git
synced 2023-10-10 13:36:59 +02:00
739 lines
18 KiB
C++
739 lines
18 KiB
C++
#include <iostream>
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#include <sstream>
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#include <stdexcept>
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#include <cstdio>
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#include <cassert>
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#include <cstdlib>
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#include <fcntl.h>
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#include <unistd.h>
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#include <cstring>
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#include <sys/stat.h>
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#include <sys/types.h>
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#include <sys/time.h>
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#include <sys/mman.h>
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#include <sys/ioctl.h>
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#include <linux/videodev2.h>
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#include "grabber/V4L2Grabber.h"
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#define CLEAR(x) memset(&(x), 0, sizeof(x))
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V4L2Grabber::V4L2Grabber(const std::string & device,
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int input,
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VideoStandard videoStandard,
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PixelFormat pixelFormat,
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int width,
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int height,
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int frameDecimation,
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int horizontalPixelDecimation,
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int verticalPixelDecimation) :
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_deviceName(device),
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_ioMethod(IO_METHOD_MMAP),
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_fileDescriptor(-1),
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_buffers(),
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_pixelFormat(pixelFormat),
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_width(width),
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_height(height),
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_lineLength(-1),
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_frameByteSize(-1),
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_frameDecimation(std::max(1, frameDecimation)),
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_noSignalCounterThreshold(50),
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_noSignalThresholdColor(ColorRgb{0,0,0}),
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_currentFrame(0),
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_noSignalCounter(0),
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_streamNotifier(nullptr),
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_imageResampler()
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{
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_imageResampler.setHorizontalPixelDecimation(std::max(1, horizontalPixelDecimation));
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_imageResampler.setVerticalPixelDecimation(std::max(1, verticalPixelDecimation));
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open_device();
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init_device(videoStandard, input);
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}
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V4L2Grabber::~V4L2Grabber()
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{
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// stop if the grabber was not stopped
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stop();
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uninit_device();
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close_device();
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}
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void V4L2Grabber::setCropping(int cropLeft, int cropRight, int cropTop, int cropBottom)
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{
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_imageResampler.setCropping(cropLeft, cropRight, cropTop, cropBottom);
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}
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void V4L2Grabber::set3D(VideoMode mode)
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{
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_imageResampler.set3D(mode);
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}
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void V4L2Grabber::setSignalThreshold(double redSignalThreshold, double greenSignalThreshold, double blueSignalThreshold, int noSignalCounterThreshold)
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{
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_noSignalThresholdColor.red = uint8_t(255*redSignalThreshold);
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_noSignalThresholdColor.green = uint8_t(255*greenSignalThreshold);
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_noSignalThresholdColor.blue = uint8_t(255*blueSignalThreshold);
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_noSignalCounterThreshold = std::max(1, noSignalCounterThreshold);
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std::cout << "V4L2GRABBER INFO: signal threshold set to: " << _noSignalThresholdColor << std::endl;
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}
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void V4L2Grabber::start()
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{
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if (_streamNotifier != nullptr && !_streamNotifier->isEnabled())
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{
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_streamNotifier->setEnabled(true);
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start_capturing();
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std::cout << "V4L2GRABBER INFO: started" << std::endl;
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}
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}
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void V4L2Grabber::stop()
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{
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if (_streamNotifier != nullptr && _streamNotifier->isEnabled())
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{
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stop_capturing();
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_streamNotifier->setEnabled(false);
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std::cout << "V4L2GRABBER INFO: stopped" << std::endl;
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}
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}
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void V4L2Grabber::open_device()
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{
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struct stat st;
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if (-1 == stat(_deviceName.c_str(), &st))
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{
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std::ostringstream oss;
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oss << "V4L2GRABBER ERROR: Cannot identify '" << _deviceName << "'";
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throw_errno_exception(oss.str());
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}
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if (!S_ISCHR(st.st_mode))
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{
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std::ostringstream oss;
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oss << "'" << _deviceName << "' is no device";
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throw_exception(oss.str());
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}
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_fileDescriptor = open(_deviceName.c_str(), O_RDWR /* required */ | O_NONBLOCK, 0);
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if (-1 == _fileDescriptor)
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{
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std::ostringstream oss;
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oss << "V4L2GRABBER ERROR: Cannot open '" << _deviceName << "'";
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throw_errno_exception(oss.str());
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}
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// create the notifier for when a new frame is available
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_streamNotifier = new QSocketNotifier(_fileDescriptor, QSocketNotifier::Read);
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_streamNotifier->setEnabled(false);
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connect(_streamNotifier, SIGNAL(activated(int)), this, SLOT(read_frame()));
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}
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void V4L2Grabber::close_device()
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{
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if (-1 == close(_fileDescriptor))
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throw_errno_exception("close");
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_fileDescriptor = -1;
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if (_streamNotifier != nullptr)
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{
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delete _streamNotifier;
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_streamNotifier = nullptr;
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}
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}
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void V4L2Grabber::init_read(unsigned int buffer_size)
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{
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_buffers.resize(1);
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_buffers[0].length = buffer_size;
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_buffers[0].start = malloc(buffer_size);
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if (!_buffers[0].start) {
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throw_exception("V4L2GRABBER ERROR: Out of memory");
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}
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}
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void V4L2Grabber::init_mmap()
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{
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struct v4l2_requestbuffers req;
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CLEAR(req);
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req.count = 4;
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req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
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req.memory = V4L2_MEMORY_MMAP;
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if (-1 == xioctl(VIDIOC_REQBUFS, &req)) {
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if (EINVAL == errno) {
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std::ostringstream oss;
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oss << "'" << _deviceName << "' does not support memory mapping";
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throw_exception(oss.str());
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} else {
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throw_errno_exception("VIDIOC_REQBUFS");
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}
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}
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if (req.count < 2) {
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std::ostringstream oss;
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oss << "Insufficient buffer memory on " << _deviceName;
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throw_exception(oss.str());
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}
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_buffers.resize(req.count);
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for (size_t n_buffers = 0; n_buffers < req.count; ++n_buffers) {
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struct v4l2_buffer buf;
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CLEAR(buf);
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buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
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buf.memory = V4L2_MEMORY_MMAP;
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buf.index = n_buffers;
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if (-1 == xioctl(VIDIOC_QUERYBUF, &buf))
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throw_errno_exception("VIDIOC_QUERYBUF");
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_buffers[n_buffers].length = buf.length;
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_buffers[n_buffers].start =
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mmap(NULL /* start anywhere */,
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buf.length,
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PROT_READ | PROT_WRITE /* required */,
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MAP_SHARED /* recommended */,
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_fileDescriptor, buf.m.offset);
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if (MAP_FAILED == _buffers[n_buffers].start)
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throw_errno_exception("mmap");
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}
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}
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void V4L2Grabber::init_userp(unsigned int buffer_size)
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{
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struct v4l2_requestbuffers req;
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CLEAR(req);
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req.count = 4;
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req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
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req.memory = V4L2_MEMORY_USERPTR;
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if (-1 == xioctl(VIDIOC_REQBUFS, &req)) {
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if (EINVAL == errno)
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{
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std::ostringstream oss;
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oss << "'" << _deviceName << "' does not support user pointer";
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throw_exception(oss.str());
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} else {
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throw_errno_exception("VIDIOC_REQBUFS");
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}
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}
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_buffers.resize(4);
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for (size_t n_buffers = 0; n_buffers < 4; ++n_buffers) {
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_buffers[n_buffers].length = buffer_size;
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_buffers[n_buffers].start = malloc(buffer_size);
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if (!_buffers[n_buffers].start) {
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throw_exception("V4L2GRABBER ERROR: Out of memory");
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}
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}
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}
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void V4L2Grabber::init_device(VideoStandard videoStandard, int input)
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{
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struct v4l2_capability cap;
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if (-1 == xioctl(VIDIOC_QUERYCAP, &cap))
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{
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if (EINVAL == errno) {
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std::ostringstream oss;
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oss << "'" << _deviceName << "' is no V4L2 device";
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throw_exception(oss.str());
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} else {
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throw_errno_exception("VIDIOC_QUERYCAP");
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}
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}
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if (!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE))
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{
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std::ostringstream oss;
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oss << "'" << _deviceName << "' is no video capture device";
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throw_exception(oss.str());
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}
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switch (_ioMethod) {
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case IO_METHOD_READ:
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if (!(cap.capabilities & V4L2_CAP_READWRITE))
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{
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std::ostringstream oss;
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oss << "'" << _deviceName << "' does not support read i/o";
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throw_exception(oss.str());
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}
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break;
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case IO_METHOD_MMAP:
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case IO_METHOD_USERPTR:
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if (!(cap.capabilities & V4L2_CAP_STREAMING))
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{
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std::ostringstream oss;
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oss << "'" << _deviceName << "' does not support streaming i/o";
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throw_exception(oss.str());
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}
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break;
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}
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/* Select video input, video standard and tune here. */
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struct v4l2_cropcap cropcap;
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CLEAR(cropcap);
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cropcap.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
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if (0 == xioctl(VIDIOC_CROPCAP, &cropcap)) {
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struct v4l2_crop crop;
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crop.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
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crop.c = cropcap.defrect; /* reset to default */
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if (-1 == xioctl(VIDIOC_S_CROP, &crop)) {
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switch (errno) {
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case EINVAL:
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/* Cropping not supported. */
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break;
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default:
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/* Errors ignored. */
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break;
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}
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}
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} else {
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/* Errors ignored. */
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}
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// set input if needed
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if (input >= 0)
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{
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if (-1 == xioctl(VIDIOC_S_INPUT, &input))
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{
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throw_errno_exception("VIDIOC_S_INPUT");
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}
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}
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// set the video standard if needed
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switch (videoStandard)
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{
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case VIDEOSTANDARD_PAL:
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{
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v4l2_std_id std_id = V4L2_STD_PAL;
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if (-1 == xioctl(VIDIOC_S_STD, &std_id))
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{
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throw_errno_exception("VIDIOC_S_STD");
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}
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}
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break;
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case VIDEOSTANDARD_NTSC:
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{
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v4l2_std_id std_id = V4L2_STD_NTSC;
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if (-1 == xioctl(VIDIOC_S_STD, &std_id))
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{
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throw_errno_exception("VIDIOC_S_STD");
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}
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}
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break;
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case VIDEOSTANDARD_NO_CHANGE:
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default:
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// No change to device settings
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break;
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}
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// get the current settings
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struct v4l2_format fmt;
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CLEAR(fmt);
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fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
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if (-1 == xioctl(VIDIOC_G_FMT, &fmt))
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{
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throw_errno_exception("VIDIOC_G_FMT");
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}
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// set the requested pixel format
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switch (_pixelFormat)
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{
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case PIXELFORMAT_UYVY:
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fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_UYVY;
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break;
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case PIXELFORMAT_YUYV:
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fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_YUYV;
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break;
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case PIXELFORMAT_RGB32:
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fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_RGB32;
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break;
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case PIXELFORMAT_NO_CHANGE:
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default:
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// No change to device settings
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break;
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}
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// set the requested withd and height
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if (_width > 0 || _height > 0)
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{
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if (_width > 0)
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{
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fmt.fmt.pix.width = _width;
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}
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if (fmt.fmt.pix.height > 0)
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{
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fmt.fmt.pix.height = _height;
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}
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}
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// set the line length
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_lineLength = fmt.fmt.pix.bytesperline;
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// set the settings
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if (-1 == xioctl(VIDIOC_S_FMT, &fmt))
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{
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throw_errno_exception("VIDIOC_S_FMT");
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}
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// get the format settings again
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// (the size may not have been accepted without an error)
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if (-1 == xioctl(VIDIOC_G_FMT, &fmt))
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{
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throw_errno_exception("VIDIOC_G_FMT");
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}
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// store width & height
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_width = fmt.fmt.pix.width;
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_height = fmt.fmt.pix.height;
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// print the eventually used width and height
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std::cout << "V4L2 width=" << _width << " height=" << _height << std::endl;
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// check pixel format and frame size
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switch (fmt.fmt.pix.pixelformat)
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{
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case V4L2_PIX_FMT_UYVY:
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_pixelFormat = PIXELFORMAT_UYVY;
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_frameByteSize = _width * _height * 2;
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std::cout << "V4L2GRABBER INFO: pixel format=UYVY" << std::endl;
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break;
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case V4L2_PIX_FMT_YUYV:
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_pixelFormat = PIXELFORMAT_YUYV;
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_frameByteSize = _width * _height * 2;
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std::cout << "V4L2GRABBER INFO: pixel format=YUYV" << std::endl;
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break;
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case V4L2_PIX_FMT_RGB32:
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_pixelFormat = PIXELFORMAT_RGB32;
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_frameByteSize = _width * _height * 4;
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std::cout << "V4L2GRABBER INFO: pixel format=RGB32" << std::endl;
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break;
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default:
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throw_exception("V4L2GRABBER ERROR: Only pixel formats UYVY, YUYV, and RGB32 are supported");
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}
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switch (_ioMethod) {
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case IO_METHOD_READ:
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init_read(fmt.fmt.pix.sizeimage);
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break;
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case IO_METHOD_MMAP:
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init_mmap();
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break;
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case IO_METHOD_USERPTR:
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init_userp(fmt.fmt.pix.sizeimage);
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break;
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}
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}
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void V4L2Grabber::uninit_device()
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{
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switch (_ioMethod) {
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case IO_METHOD_READ:
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free(_buffers[0].start);
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break;
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case IO_METHOD_MMAP:
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for (size_t i = 0; i < _buffers.size(); ++i)
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if (-1 == munmap(_buffers[i].start, _buffers[i].length))
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throw_errno_exception("munmap");
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break;
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case IO_METHOD_USERPTR:
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for (size_t i = 0; i < _buffers.size(); ++i)
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free(_buffers[i].start);
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break;
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}
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_buffers.resize(0);
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}
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void V4L2Grabber::start_capturing()
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{
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switch (_ioMethod) {
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case IO_METHOD_READ:
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/* Nothing to do. */
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break;
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case IO_METHOD_MMAP:
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{
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for (size_t i = 0; i < _buffers.size(); ++i) {
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struct v4l2_buffer buf;
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CLEAR(buf);
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buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
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buf.memory = V4L2_MEMORY_MMAP;
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buf.index = i;
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if (-1 == xioctl(VIDIOC_QBUF, &buf))
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throw_errno_exception("VIDIOC_QBUF");
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}
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v4l2_buf_type type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
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if (-1 == xioctl(VIDIOC_STREAMON, &type))
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throw_errno_exception("VIDIOC_STREAMON");
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break;
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}
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case IO_METHOD_USERPTR:
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{
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for (size_t i = 0; i < _buffers.size(); ++i) {
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struct v4l2_buffer buf;
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CLEAR(buf);
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buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
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buf.memory = V4L2_MEMORY_USERPTR;
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buf.index = i;
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buf.m.userptr = (unsigned long)_buffers[i].start;
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buf.length = _buffers[i].length;
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if (-1 == xioctl(VIDIOC_QBUF, &buf))
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throw_errno_exception("VIDIOC_QBUF");
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}
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v4l2_buf_type type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
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if (-1 == xioctl(VIDIOC_STREAMON, &type))
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throw_errno_exception("VIDIOC_STREAMON");
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break;
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}
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}
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}
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void V4L2Grabber::stop_capturing()
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{
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enum v4l2_buf_type type;
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switch (_ioMethod) {
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case IO_METHOD_READ:
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/* Nothing to do. */
|
|
break;
|
|
|
|
case IO_METHOD_MMAP:
|
|
case IO_METHOD_USERPTR:
|
|
type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
|
|
if (-1 == xioctl(VIDIOC_STREAMOFF, &type))
|
|
throw_errno_exception("VIDIOC_STREAMOFF");
|
|
break;
|
|
}
|
|
}
|
|
|
|
int V4L2Grabber::read_frame()
|
|
{
|
|
bool rc = false;
|
|
|
|
struct v4l2_buffer buf;
|
|
|
|
switch (_ioMethod) {
|
|
case IO_METHOD_READ:
|
|
int size;
|
|
if ((size = read(_fileDescriptor, _buffers[0].start, _buffers[0].length)) == -1)
|
|
{
|
|
switch (errno)
|
|
{
|
|
case EAGAIN:
|
|
return 0;
|
|
|
|
case EIO:
|
|
/* Could ignore EIO, see spec. */
|
|
|
|
/* fall through */
|
|
|
|
default:
|
|
throw_errno_exception("read");
|
|
}
|
|
}
|
|
|
|
rc = process_image(_buffers[0].start, size);
|
|
break;
|
|
|
|
case IO_METHOD_MMAP:
|
|
CLEAR(buf);
|
|
|
|
buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
|
|
buf.memory = V4L2_MEMORY_MMAP;
|
|
|
|
if (-1 == xioctl(VIDIOC_DQBUF, &buf))
|
|
{
|
|
switch (errno)
|
|
{
|
|
case EAGAIN:
|
|
return 0;
|
|
|
|
case EIO:
|
|
/* Could ignore EIO, see spec. */
|
|
|
|
/* fall through */
|
|
|
|
default:
|
|
throw_errno_exception("VIDIOC_DQBUF");
|
|
}
|
|
}
|
|
|
|
assert(buf.index < _buffers.size());
|
|
|
|
rc = process_image(_buffers[buf.index].start, buf.bytesused);
|
|
|
|
if (-1 == xioctl(VIDIOC_QBUF, &buf))
|
|
{
|
|
throw_errno_exception("VIDIOC_QBUF");
|
|
}
|
|
|
|
break;
|
|
|
|
case IO_METHOD_USERPTR:
|
|
CLEAR(buf);
|
|
|
|
buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
|
|
buf.memory = V4L2_MEMORY_USERPTR;
|
|
|
|
if (-1 == xioctl(VIDIOC_DQBUF, &buf))
|
|
{
|
|
switch (errno)
|
|
{
|
|
case EAGAIN:
|
|
return 0;
|
|
|
|
case EIO:
|
|
/* Could ignore EIO, see spec. */
|
|
|
|
/* fall through */
|
|
|
|
default:
|
|
throw_errno_exception("VIDIOC_DQBUF");
|
|
}
|
|
}
|
|
|
|
for (size_t i = 0; i < _buffers.size(); ++i)
|
|
{
|
|
if (buf.m.userptr == (unsigned long)_buffers[i].start && buf.length == _buffers[i].length)
|
|
{
|
|
break;
|
|
}
|
|
}
|
|
|
|
rc = process_image((void *)buf.m.userptr, buf.bytesused);
|
|
|
|
if (-1 == xioctl(VIDIOC_QBUF, &buf))
|
|
{
|
|
throw_errno_exception("VIDIOC_QBUF");
|
|
}
|
|
break;
|
|
}
|
|
|
|
return rc ? 1 : 0;
|
|
}
|
|
|
|
bool V4L2Grabber::process_image(const void *p, int size)
|
|
{
|
|
if (++_currentFrame >= _frameDecimation)
|
|
{
|
|
// We do want a new frame...
|
|
|
|
if (size != _frameByteSize)
|
|
{
|
|
std::cout << "V4L2GRABBER ERROR: Frame too small: " << size << " != " << _frameByteSize << std::endl;
|
|
}
|
|
else
|
|
{
|
|
process_image(reinterpret_cast<const uint8_t *>(p));
|
|
_currentFrame = 0; // restart counting
|
|
return true;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
void V4L2Grabber::process_image(const uint8_t * data)
|
|
{
|
|
Image<ColorRgb> image(0, 0);
|
|
_imageResampler.processImage(data, _width, _height, _lineLength, _pixelFormat, image);
|
|
|
|
// check signal (only in center of the resulting image, because some grabbers have noise values along the borders)
|
|
bool noSignal = true;
|
|
for (unsigned x = 0; noSignal && x < (image.width()>>1); ++x)
|
|
{
|
|
int xImage = (image.width()>>2) + x;
|
|
|
|
for (unsigned y = 0; noSignal && y < (image.height()>>1); ++y)
|
|
{
|
|
int yImage = (image.height()>>2) + y;
|
|
|
|
ColorRgb & rgb = image(xImage, yImage);
|
|
noSignal &= rgb <= _noSignalThresholdColor;
|
|
}
|
|
}
|
|
|
|
if (noSignal)
|
|
{
|
|
++_noSignalCounter;
|
|
}
|
|
else
|
|
{
|
|
if (_noSignalCounter >= _noSignalCounterThreshold)
|
|
{
|
|
std::cout << "V4L2GRABBER INFO: " << "Signal detected" << std::endl;
|
|
}
|
|
|
|
_noSignalCounter = 0;
|
|
}
|
|
|
|
if (_noSignalCounter < _noSignalCounterThreshold)
|
|
{
|
|
emit newFrame(image);
|
|
}
|
|
else if (_noSignalCounter == _noSignalCounterThreshold)
|
|
{
|
|
std::cout << "V4L2GRABBER INFO: " << "Signal lost" << std::endl;
|
|
}
|
|
}
|
|
|
|
int V4L2Grabber::xioctl(int request, void *arg)
|
|
{
|
|
int r;
|
|
|
|
do
|
|
{
|
|
r = ioctl(_fileDescriptor, request, arg);
|
|
}
|
|
while (-1 == r && EINTR == errno);
|
|
|
|
return r;
|
|
}
|
|
|
|
void V4L2Grabber::throw_exception(const std::string & error)
|
|
{
|
|
std::ostringstream oss;
|
|
oss << error << " ERROR";
|
|
throw std::runtime_error(oss.str());
|
|
}
|
|
|
|
void V4L2Grabber::throw_errno_exception(const std::string & error)
|
|
{
|
|
std::ostringstream oss;
|
|
oss << error << " ERROR " << errno << ", " << strerror(errno);
|
|
throw std::runtime_error(oss.str());
|
|
}
|