From 558ad6a11f8d10d7cd09bb795c81e29a5241ad6b Mon Sep 17 00:00:00 2001 From: johan Date: Sat, 11 Jan 2014 20:43:55 +0100 Subject: [PATCH] Added setting of PAL/NTSC/NO_CHANGE and input Former-commit-id: aee087b65b122e34e46b15854b94c720cbbec6b2 --- test/v4l2png/V4L2Grabber.cpp | 229 ++++++++++++++++++++++------------- test/v4l2png/V4L2Grabber.h | 20 ++- test/v4l2png/v4l2png.cpp | 5 +- 3 files changed, 166 insertions(+), 88 deletions(-) diff --git a/test/v4l2png/V4L2Grabber.cpp b/test/v4l2png/V4L2Grabber.cpp index bee23e30..03da150d 100644 --- a/test/v4l2png/V4L2Grabber.cpp +++ b/test/v4l2png/V4L2Grabber.cpp @@ -19,62 +19,70 @@ #define CLEAR(x) memset(&(x), 0, sizeof(x)) -V4L2Grabber::V4L2Grabber() : - _deviceName("/dev/video0"), +V4L2Grabber::V4L2Grabber(const std::string &device, int input, VideoStandard videoStandard, double fps) : + _deviceName(device), _ioMethod(IO_METHOD_MMAP), _fileDescriptor(-1), - _buffers() + _buffers(), + _width(0), + _height(0) { + open_device(); + init_device(videoStandard, input); } V4L2Grabber::~V4L2Grabber() { + uninit_device(); + close_device(); } void V4L2Grabber::start() { - open_device(); - init_device(); start_capturing(); +} - int count = 100; - while (count-- > 0) { - for (;;) { - fd_set fds; - struct timeval tv; - int r; +void V4L2Grabber::capture() +{ + int count = 1; + while (count-- > 0) { + for (;;) { + fd_set fds; + struct timeval tv; + int r; - FD_ZERO(&fds); - FD_SET(_fileDescriptor, &fds); + FD_ZERO(&fds); + FD_SET(_fileDescriptor, &fds); - /* Timeout. */ - tv.tv_sec = 2; - tv.tv_usec = 0; + /* Timeout. */ + tv.tv_sec = 2; + tv.tv_usec = 0; - r = select(_fileDescriptor + 1, &fds, NULL, NULL, &tv); + r = select(_fileDescriptor + 1, &fds, NULL, NULL, &tv); - if (-1 == r) - { - if (EINTR == errno) - continue; - errno_exit("select"); - } + if (-1 == r) + { + if (EINTR == errno) + continue; + errno_exit("select"); + } - if (0 == r) - { - fprintf(stderr, "select timeout\n"); - exit(EXIT_FAILURE); - } + if (0 == r) + { + fprintf(stderr, "select timeout\n"); + exit(EXIT_FAILURE); + } - if (read_frame()) - break; - /* EAGAIN - continue select loop. */ - } - } + if (read_frame()) + break; + /* EAGAIN - continue select loop. */ + } + } +} - stop_capturing(); - uninit_device(); - close_device(); +void V4L2Grabber::stop() +{ + stop_capturing(); } void V4L2Grabber::open_device() @@ -207,14 +215,10 @@ void V4L2Grabber::init_userp(unsigned int buffer_size) } } -void V4L2Grabber::init_device() +void V4L2Grabber::init_device(VideoStandard videoStandard, int input) { struct v4l2_capability cap; - struct v4l2_cropcap cropcap; - struct v4l2_crop crop; - struct v4l2_format fmt; - - if (-1 == xioctl(VIDIOC_QUERYCAP, &cap)) + if (-1 == xioctl(VIDIOC_QUERYCAP, &cap)) { if (EINVAL == errno) { fprintf(stderr, "%s is no V4L2 device\n", _deviceName.c_str()); @@ -252,13 +256,14 @@ void V4L2Grabber::init_device() /* Select video input, video standard and tune here. */ - + struct v4l2_cropcap cropcap; CLEAR(cropcap); cropcap.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; if (0 == xioctl(VIDIOC_CROPCAP, &cropcap)) { - crop.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; + struct v4l2_crop crop; + crop.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; crop.c = cropcap.defrect; /* reset to default */ if (-1 == xioctl(VIDIOC_S_CROP, &crop)) { @@ -275,24 +280,61 @@ void V4L2Grabber::init_device() /* Errors ignored. */ } + // set input if needed + if (input >= 0) + { + if (-1 == xioctl(VIDIOC_S_INPUT, &input)) + { + errno_exit("VIDIOC_S_INPUT"); + } + } + // set the video standard if needed + switch (videoStandard) + { + case PAL: + { + v4l2_std_id std_id = V4L2_STD_PAL; + if (-1 == xioctl(VIDIOC_S_STD, &std_id)) + { + errno_exit("VIDIOC_S_STD"); + } + } + break; + case NTSC: + { + v4l2_std_id std_id = V4L2_STD_NTSC; + if (-1 == xioctl(VIDIOC_S_STD, &std_id)) + { + errno_exit("VIDIOC_S_STD"); + } + } + break; + case NO_CHANGE: + default: + // No change to device settings + break; + } + + // get the current settings + struct v4l2_format fmt; CLEAR(fmt); - fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; - - /* Preserve original settings as set by v4l2-ctl for example */ if (-1 == xioctl(VIDIOC_G_FMT, &fmt)) { - errno_exit("VIDIOC_G_FMT"); + errno_exit("VIDIOC_G_FMT"); } -// /* Buggy driver paranoia. */ -// min = fmt.fmt.pix.width * 2; -// if (fmt.fmt.pix.bytesperline < min) -// fmt.fmt.pix.bytesperline = min; -// min = fmt.fmt.pix.bytesperline * fmt.fmt.pix.height; -// if (fmt.fmt.pix.sizeimage < min) -// fmt.fmt.pix.sizeimage = min; + // check pixel format + if (fmt.fmt.pix.pixelformat != V4L2_PIX_FMT_UYVY) + { + exit(EXIT_FAILURE); + } + + // store width & height + _width = fmt.fmt.pix.width; + _height = fmt.fmt.pix.height; + std::cout << "V4L2 width=" << _width << " height=" << _height << std::endl; switch (_ioMethod) { case IO_METHOD_READ: @@ -403,8 +445,11 @@ int V4L2Grabber::read_frame() switch (_ioMethod) { case IO_METHOD_READ: - if (-1 == read(_fileDescriptor, _buffers[0].start, _buffers[0].length)) { - switch (errno) { + int size; + if ((size = read(_fileDescriptor, _buffers[0].start, _buffers[0].length)) == -1) + { + switch (errno) + { case EAGAIN: return 0; @@ -418,7 +463,7 @@ int V4L2Grabber::read_frame() } } - process_image(_buffers[0].start, _buffers[0].length); + process_image(_buffers[0].start, size); break; case IO_METHOD_MMAP: @@ -427,8 +472,10 @@ int V4L2Grabber::read_frame() buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; buf.memory = V4L2_MEMORY_MMAP; - if (-1 == xioctl(VIDIOC_DQBUF, &buf)) { - switch (errno) { + if (-1 == xioctl(VIDIOC_DQBUF, &buf)) + { + switch (errno) + { case EAGAIN: return 0; @@ -444,10 +491,13 @@ int V4L2Grabber::read_frame() assert(buf.index < _buffers.size()); - process_image(_buffers[buf.index].start, buf.bytesused); + process_image(_buffers[buf.index].start, buf.bytesused); if (-1 == xioctl(VIDIOC_QBUF, &buf)) + { errno_exit("VIDIOC_QBUF"); + } + break; case IO_METHOD_USERPTR: @@ -456,8 +506,10 @@ int V4L2Grabber::read_frame() buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; buf.memory = V4L2_MEMORY_USERPTR; - if (-1 == xioctl(VIDIOC_DQBUF, &buf)) { - switch (errno) { + if (-1 == xioctl(VIDIOC_DQBUF, &buf)) + { + switch (errno) + { case EAGAIN: return 0; @@ -472,14 +524,19 @@ int V4L2Grabber::read_frame() } for (size_t i = 0; i < _buffers.size(); ++i) - if (buf.m.userptr == (unsigned long)_buffers[i].start - && buf.length == _buffers[i].length) + { + if (buf.m.userptr == (unsigned long)_buffers[i].start && buf.length == _buffers[i].length) + { break; + } + } - process_image((void *)buf.m.userptr, buf.bytesused); + process_image((void *)buf.m.userptr, buf.bytesused); - if (-1 == xioctl(VIDIOC_QBUF, &buf)) + if (-1 == xioctl(VIDIOC_QBUF, &buf)) + { errno_exit("VIDIOC_QBUF"); + } break; } @@ -488,38 +545,44 @@ int V4L2Grabber::read_frame() void V4L2Grabber::process_image(const void *p, int size) { - if (size != 2*720*480) - { - std::cout << "Frame too small: " << size << "<" << (2*720*480) << std::endl; - return; - } + if (size != 2*_width*_height) + { + std::cout << "Frame too small: " << size << " != " << (2*_width*_height) << std::endl; + } + else + { + process_image(reinterpret_cast(p)); + } +} - std::cout << "process image of size = " << size << std::endl; +void V4L2Grabber::process_image(const uint8_t * data) +{ + std::cout << "process image" << std::endl; - const uint8_t * data = reinterpret_cast(p); - - - QImage image(720, 480, QImage::Format_RGB888); + QImage image(_width, _height, QImage::Format_RGB888); for (int y = 0; y < image.height(); ++y) { for (int x = 0; x < image.width(); ++x) { - uint8_t value = data[(720 * y + x) * 2 + 1]; - image.setPixel(x, y, qRgb(value, value, value)); + uint8_t value = data[(image.width() * y + x) * 2 + 1]; + //std::cout << "data = " << int(value) << std::endl; + image.setPixel(x, y, qRgb(value, value, value)); } } - image.save("/home/pi/screenshot.png"); + image.save("screenshot.png"); } int V4L2Grabber::xioctl(int request, void *arg) { int r; - do { - r = ioctl(_fileDescriptor, request, arg); - } while (-1 == r && EINTR == errno); + do + { + r = ioctl(_fileDescriptor, request, arg); + } + while (-1 == r && EINTR == errno); return r; } diff --git a/test/v4l2png/V4L2Grabber.h b/test/v4l2png/V4L2Grabber.h index 1484973d..706fc493 100644 --- a/test/v4l2png/V4L2Grabber.h +++ b/test/v4l2png/V4L2Grabber.h @@ -10,11 +10,20 @@ class V4L2Grabber { public: - V4L2Grabber(); + enum VideoStandard { + PAL, NTSC, NO_CHANGE + }; + +public: + V4L2Grabber(const std::string & device, int input, VideoStandard videoStandard, double fps); virtual ~V4L2Grabber(); void start(); + void capture(); + + void stop(); + private: void open_device(); @@ -26,7 +35,7 @@ private: void init_userp(unsigned int buffer_size); - void init_device(); + void init_device(VideoStandard videoStandard, int input); void uninit_device(); @@ -36,7 +45,9 @@ private: int read_frame(); - void process_image(const void *p, int size); + void process_image(const void *p, int size); + + void process_image(const uint8_t *p); int xioctl(int request, void *arg); @@ -59,4 +70,7 @@ private: const io_method _ioMethod; int _fileDescriptor; std::vector _buffers; + + int _width; + int _height; }; diff --git a/test/v4l2png/v4l2png.cpp b/test/v4l2png/v4l2png.cpp index a2e077ff..09c664c2 100644 --- a/test/v4l2png/v4l2png.cpp +++ b/test/v4l2png/v4l2png.cpp @@ -40,9 +40,10 @@ int main(int argc, char** argv) return 1; } - V4L2Grabber grabber; + V4L2Grabber grabber("/dev/video0", 0, V4L2Grabber::PAL, 10.0); grabber.start(); + grabber.capture(); + grabber.stop(); return 0; } -