hyperion.ng/include/grabber/DispmanxFrameGrabber.h
Matthias Reichl f584b05de5 dispmanx: fix grabber issues with certain widths and support cropping (#634)
* dispmanx: fix grabber issues with certain widths and support cropping

The dispmanx grabber will produce garbage output if the destination
pitch is not set to a multiple of 64 bytes (16 RGBA pixels).

It can also fail when retrieving only a part of the image
(eg in 3DSBS or TAB mode).

Handle these cases by capturing the full image into a separate
buffer with the pitch set to an appropriate value and manually
handle 3D SBS/TAB left/top half copying.

At this point supporting cropping like in the V4L2 grabber is
rather easy and added as well. This'll help handling overscan
setups (old TVs) and removing (possibly asymmetric) overscan
borders.

Cropping is disabled in video capture mode (when the
DISPMANX_SNAPSHOT_FILL flag is set).

Signed-off-by: Matthias Reichl <hias@horus.com>

* hyperion-dispmanx: add optional crop values and 3D mode options

Signed-off-by: Matthias Reichl <hias@horus.com>

* hyperiond: support cropping on the dispmanx grabber

Honor cropLeft, cropRight, cropTop and cropBottom settings in
the framegrabber section of the conf file to control cropping.

Signed-off-by: Matthias Reichl <hias@horus.com>

Former-commit-id: bbb55f6621b90384e417f37da4f2543d112ef57a
2016-05-18 11:26:25 +02:00

88 lines
2.3 KiB
C++

#pragma once
// BCM includes
#pragma GCC system_header
#include <bcm_host.h>
// STL includes
#include <cstdint>
// Utils includes
#include <utils/Image.h>
#include <utils/ColorRgba.h>
#include <utils/VideoMode.h>
///
/// The DispmanxFrameGrabber is used for creating snapshots of the display (screenshots) with a
/// downsized and scaled resolution.
///
class DispmanxFrameGrabber
{
public:
///
/// Construct a DispmanxFrameGrabber that will capture snapshots with specified dimensions.
///
/// @param[in] width The width of the captured screenshot
/// @param[in] height The heigth of the captured screenshot
///
DispmanxFrameGrabber(const unsigned width, const unsigned height);
~DispmanxFrameGrabber();
///
/// Updates the frame-grab flags as used by the VC library for frame grabbing
///
/// @param vc_flags The snapshot grabbing mask
///
void setFlags(const int vc_flags);
///
/// Set the video mode (2D/3D)
/// @param[in] mode The new video mode
///
void setVideoMode(const VideoMode videoMode);
void setCropping(const unsigned cropLeft, const unsigned cropRight,
const unsigned cropTop, const unsigned cropBottom);
///
/// Captures a single snapshot of the display and writes the data to the given image. The
/// provided image should have the same dimensions as the configured values (_width and
/// _height)
///
/// @param[out] image The snapped screenshot (should be initialized with correct width and
/// height)
///
void grabFrame(Image<ColorRgba> & image);
private:
/// Handle to the display that is being captured
DISPMANX_DISPLAY_HANDLE_T _vc_display;
/// Handle to the resource for storing the captured snapshot
DISPMANX_RESOURCE_HANDLE_T _vc_resource;
/// Rectangle of the captured resource that is transfered to user space
VC_RECT_T _rectangle;
/// Flags (transforms) for creating snapshots
int _vc_flags;
/// With of the captured snapshot [pixels]
const unsigned _width;
/// Height of the captured snapshot [pixels]
const unsigned _height;
// the selected VideoMode
VideoMode _videoMode;
// number of pixels to crop after capturing
unsigned _cropLeft, _cropRight, _cropTop, _cropBottom;
// temp buffer when capturing with unsupported pitch size or
// when we need to crop the image
ColorRgba* _captureBuffer;
// size of the capture buffer in Pixels
unsigned _captureBufferSize;
};