Intel gives example to align RGB camera and Depth(IR) camera, but i need adapt to opencv.
the example show only "align in render", so i can't use them because i will use below function.
Mat color(Size(640, 480), CV_8UC3, (void*)color_frame.get_data(), Mat::AUTO_STEP);
i need align frame like below sentences form.
rs2::frameset frames = pipe.wait_for_frames();
rs2::frame color_frame = frames.get_color_frame();
rs2::frame depth_frame = color_map(frames.get_depth_frame());
So, is it possible that i can use align function like below ex) sentence?
ex) rs2:: frameset align_frame = ...... allocate_composite_frame......
OR, is there any function like "depth_aligned_to_color" in D435 like SR300?
The frameset will be returned after align function is called, you can retrieve back the aligned color/depth image to set into CV function without problem. Please download the latest version LibRS and check the rs-align.cpp, attach code snippet below.
//Get processed aligned frame
auto processed = align.process(frameset);
// Trying to get both other and aligned depth frames
rs2::video_frame other_frame = processed.first(align_to);
rs2::depth_frame aligned_depth_frame = processed.get_depth_frame();
Related
Here is the picture I take with my USB camera. My camera has an angle with horizontal line, the target is on the bottom, with parallel and orthogonal lines delimiting rectangles. Post-it is a control marker of the center-rectangle.
Then I process several step-by-step processing in order to adjust the 'tilt' of the view and to extract lines.
Here is the line extraction without transform :
{"type":"toGray"} => mat.cvtColor( cv4.COLOR_BGR2GRAY);
{"type":"toBlur","size":10} => mat.gaussianBlur( new cv4.Size( size, size),0);
{"type":"toCanny","low":50,"high":150} => mat.canny( low_threshold, high_threshold);
{"type":"getLines","rho":1,"theta":0.017453292222222222,"threshold":15,"min_line_length":50,"max_line_gap":20 }] => let lines = mat.houghLinesP( rho, theta, threshold, min_line_length, max_line_gap);
Result is :
Now, I want to correct the tilt of view, using 'warpAffine' function, before extracting lines.
I select four points of the centered rectangle, in order to build two "three points array" (src, dst):
matTransf = cv4.getAffineTransform( srcPoints, dstPoints);
resultMat = mat.warpAffine( matTransf, new cv4.Size( mat.cols, mat.rows));
The result is the following:
Where is the mistake ?
I have tried too :
// four points at each corner of the rectangle, srcPoints for the picture, and dstPoints for the theoric shape
// With getPerspectiveTransform
matTransf = cv4.getPerspectiveTransform( srcPoints, dstPoints);
resultMat = mat.warpPerspective( matTransf, new cv4.Size( mat.cols, mat.rows));
// With findHomography
let result = cv4.findHomography( srcPoints, dstPoints);
matTransf = result.homography;
resultMat = mat.warpPerspective( matTransf, new cv4.Size( mat.cols, mat.rows));
Result is :
Best regards.
The transformation is not an affinity, it is a perspective described by a homography. Select in the image four corners of a physical rectangle, map them to points in a rectangle with the same aspect ratio as the physical one, estimate the homography from them (findHomography), finally warp (warpPerspective).
It seems there are lots of related topics out there, but I was not able to find the answer I'm searching for.
I'm using JavaCV and FFmpegFrameGrabber to get an image from the middle of the video. If an mp4 file has a "Rotation" metadata field (like 90 or 270), I'm getting an image that is positioned not correctly. I wanted to get Orientation from FFmpegFrameGrabber, but could not find a way to do so.
Is there a way to tell FFmpegFrameGrabber to respect orientation, or is there a way to get this value somehow using JavaCV?
Just in case the code that I have so far
FFmpegFrameGrabber g = new FFmpegFrameGrabber(input);
g.start();
g.getVideoMetadata(); // <-- this thing is empty
try {
g.setFrameNumber(g.getLengthInFrames() / 2);
Java2DFrameConverter converter = new Java2DFrameConverter();
Frame frame = g.grabImage();
BufferedImage bufferedImage = converter.convert(frame);
ImageIO.write(bufferedImage, "jpeg", output);
} finally {
g.stop();
}
When I try to use fraxel's answer on
http://stackoverflow.com/questions/10269099/pil-convert-gif-frames-to-jpg
on the image http://24.media.tumblr.com/fffcc2d8e980fbba4f87d51ed4916b87/tumblr_mh8uaqMo2I1rkp3avo2_250.gif
I get ok data for some, but then for some I get missing data it looks like, e.g.
Correct
Missing
To display these I use imagemagick's display foo* and then use space to move through the images ... is it possible imagemagick is reading them wrong?
Edit:
Even when using convert and then displaying via display foo* I get the following
Could this be a characteristic of the gif then?
If you can stick to ImageMagick then it is very simple to solve this:
convert input.gif -coalesce output.png
Otherwise, you will have to consider the different forms of how each GIF frame can be constructed. For this specific type of GIF, and also the other one shown in your other question, the following code works (note that in your earlier question, the accepted answer doesn't actually make all the split parts transparent -- at least with the latest released PIL):
import sys
from PIL import Image, ImageSequence
img = Image.open(sys.argv[1])
pal = img.getpalette()
prev = img.convert('RGBA')
prev_dispose = True
for i, frame in enumerate(ImageSequence.Iterator(img)):
dispose = frame.dispose
if frame.tile:
x0, y0, x1, y1 = frame.tile[0][1]
if not frame.palette.dirty:
frame.putpalette(pal)
frame = frame.crop((x0, y0, x1, y1))
bbox = (x0, y0, x1, y1)
else:
bbox = None
if dispose is None:
prev.paste(frame, bbox, frame.convert('RGBA'))
prev.save('foo%02d.png' % i)
prev_dispose = False
else:
if prev_dispose:
prev = Image.new('RGBA', img.size, (0, 0, 0, 0))
out = prev.copy()
out.paste(frame, bbox, frame.convert('RGBA'))
out.save('foo%02d.png' % i)
Ultimately you will have to recreate what -coalesce does, since it is likely that the code above may not work with certain GIF images.
You should try keeping the whole history of frames in "background", instead of :
background = Image.new("RGB", size, (255,255,255))
background.paste( lastframe )
background.paste( im2 )
Just create the "background" once before the loop, then only paste() frame on it, it should work.
in a school project i would like to do the following step to have a watermaked image in matlab
extract the edges from an image
insert a mark on this edge
reconstruct the image
extract the mark
could some one give me a link to have a good idea how to do it or help me to do that?
thank you in advance
You want to add a watermark to an image? Why not just overlay the whole thing.
if you have an image
img = imread('myimage.jpg')
wm = imread('watermark.jpg')
You can just resize the watermark to the size of the image
wm_rs = imresize(wm, [size(img,1) size(img,2)], 'lanczos2');
img_wm(wm_rs ~= 0) = wm_rs; %This sets non-black pixels to be the watermark. (You'll have to slightly modify this for color images)
If you want to put it on the edges of the image, you can extract them like this
edges = edge(rgb2gray(img),'canny')
Then you can set the pixels where the edges exist to be watermark pixels
img_wm = img;
img_wm(edges ~= 0) = wm_rs(edges~=0);
Instead of direct assignment you can play around with using a mix of the img and wm_rs pixel values if you want transparency.
You'll probably have to adjust some of what I said to color images, but most should be the same.
Here, is a nice and simple example how you can embed watermarks using MATLAB (in the spatial domain): http://imageprocessingblog.com/digital-watermarking/
see example below(R2017b or later release):
% your params
img = imread('printedtext.png');
Transparency = 0.6;
fontColor = [1,1,1]; % RGB,range [0,1]
position = [700,200];
%% add watermark
mask = zeros(size(img),'like',img);
outimg = insertText(mask,position,'china', ...
'BoxOpacity',0,...
'FontSize',200,...
'TextColor', 'white');
bwMask = imbinarize(rgb2gray(outimg));
finalImg = labeloverlay(img,bwMask,...
'Transparency',Transparency,...
'Colormap',fontColor);
imshow(finalImg)
I want to be able to draw images to the viewport in my 3d Max Plugin,
The GraphicsWindow Class has functions for drawing 3d objects in the viewport but these drawing calls are limited by the current viewport and graphics render limits.
This is undesirable as the image I want to draw should always be drawn no matter what graphics mode 3d max is in and or hardware is used, futher i am only drawing 2d images so there is no need to draw it in a 3d context.
I have managed to get the HWND of the viewport and the max sdk has the function
DrawIconButton();
and i have tried using this function but it does not function properly, the image flickers randomly with user interaction, but disappears when there is no interactivity.
i Have implemented this function in the
RedrawViewsCallback function, however the DrawIconButton() function is not documented and i am not sure if this is the correct way to implemented it.
Here is the code i am using to draw the image:
void Sketch_RedrawViewsCallback::proc (Interface * ip)
{
Interface10* ip10 = GetCOREInterface10();
ViewExp* viewExp = ip10->GetActiveViewport();
ViewExp10* currentViewport;
if (viewExp != NULL)
{
currentViewport = reinterpret_cast<ViewExp10*>(viewExp->Execute(ViewExp::kEXECUTE_GET_VIEWEXP_10));
} else {
return;
}
GraphicsWindow* gw = currentViewport->getGW();
HWND ViewportWindow = gw->getHWnd();
HDC hdc = GetDC(ViewportWindow);
HBITMAP bitmapImage = LoadBitmap(hInstance, MAKEINTRESOURCE(IDB_BITMAP1));
Rect rbox(IPoint2(0,0),IPoint2(48,48));
DrawIconButton(hdc, bitmapImage, rbox, rbox, true);
ReleaseDC(ViewportWindow, hdc);
ip->ReleaseViewport(currentViewport);
};
I could not find a way to draw directly to the view-port window, however I have solved the problem by using a transparent modeless dialog box.
May be a complete redraw will solve the issue. ForceCompleteRedraw