hyperion.ng/libsrc/grabber/framebuffer/FramebufferFrameGrabber.cpp
2018-12-27 23:11:32 +01:00

105 lines
2.4 KiB
C++
Executable File

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <linux/fb.h>
#include <sys/mman.h>
#include <sys/ioctl.h>
// STL includes
#include <iostream>
// Local includes
#include <grabber/FramebufferFrameGrabber.h>
FramebufferFrameGrabber::FramebufferFrameGrabber(const QString & device, const unsigned width, const unsigned height)
: Grabber("FRAMEBUFFERGRABBER", width, height)
, _fbfd(0)
, _fbp(0)
, _fbDevice()
{
setDevicePath(device);
}
FramebufferFrameGrabber::~FramebufferFrameGrabber()
{
}
int FramebufferFrameGrabber::grabFrame(Image<ColorRgb> & image)
{
if (!_enabled) return 0;
struct fb_var_screeninfo vinfo;
unsigned capSize, bytesPerPixel;
PixelFormat pixelFormat;
/* Open the framebuffer device */
_fbfd = open(QSTRING_CSTR(_fbDevice), O_RDONLY);
/* get variable screen information */
ioctl (_fbfd, FBIOGET_VSCREENINFO, &vinfo);
bytesPerPixel = vinfo.bits_per_pixel / 8;
capSize = vinfo.xres * vinfo.yres * bytesPerPixel;
switch (vinfo.bits_per_pixel)
{
case 16: pixelFormat = PIXELFORMAT_BGR16; break;
case 24: pixelFormat = PIXELFORMAT_BGR24; break;
case 32: pixelFormat = PIXELFORMAT_BGR32; break;
default:
Error(_log, "Unknown pixel format: %d bits per pixel", vinfo.bits_per_pixel);
close(_fbfd);
return -1;
}
/* map the device to memory */
_fbp = (unsigned char*)mmap(0, capSize, PROT_READ, MAP_PRIVATE | MAP_NORESERVE, _fbfd, 0);
_imageResampler.setHorizontalPixelDecimation(vinfo.xres/_width);
_imageResampler.setVerticalPixelDecimation(vinfo.yres/_height);
_imageResampler.processImage(_fbp,
vinfo.xres,
vinfo.yres,
vinfo.xres * bytesPerPixel,
pixelFormat,
image);
munmap(_fbp, capSize);
close(_fbfd);
return 0;
}
void FramebufferFrameGrabber::setDevicePath(const QString& path)
{
if(_fbDevice != path)
{
_fbDevice = path;
int result;
struct fb_var_screeninfo vinfo;
// Check if the framebuffer device can be opened and display the current resolution
_fbfd = open(QSTRING_CSTR(_fbDevice), O_RDONLY);
if (_fbfd == 0)
{
Error(_log, "Error openning %s", QSTRING_CSTR(_fbDevice));
}
else
{
// get variable screen information
result = ioctl (_fbfd, FBIOGET_VSCREENINFO, &vinfo);
if (result != 0)
{
Error(_log, "Could not get screen information");
}
else
{
Info(_log, "Display opened with resolution: %dx%d@%dbit", vinfo.xres, vinfo.yres, vinfo.bits_per_pixel);
}
close(_fbfd);
}
}
}