Stack Overflow
Stack Overflow

Questions tagged [scanline]

47 questions
0
votes
3 answers

Fast crop .png images in Delphi

I don't know what to do here anymore, so I hope that somebody can help me. I'm using Delphi 10.4 and Windows 10. Basically, my problem is that cutting a part of the .png image with transparent background is to slow. I use scanline. I have one…
brane
  • 41
  • 6
0
votes
0 answers

How can I remove horizontal line glitches from an image?

I am working on art project where we are automatically taking pictures of a petri dish, which is illuminated by a small LCD screen. Oftentimes, there appears to be "glitches" in the image (see image with glitch), it always look the same, a short,…
Sofian Audry
  • 1
0
votes
0 answers

ScanLine flood fill Thread 1: EXC_BAD_ACCESS (code=1, address=0x10b48427c)

I used https://github.com/Chintan-Dave/UIImageScanlineFloodfill to implement Scanline flood fill in my swift code. Sometimes the image is filled sometimes it throws an exception like Thread 1: EXC_BAD_ACCESS (code=1, address=0x10b48427c) in…
user9395315
0
votes
0 answers

PHP shell_exec() Behaves Differently Than Terminal Command Line MacOS

Scanline is a simple command line utility used for scanning documents from a twain scanner. http://blog.scottkleper.com/scanline-command-line-scanner-for-mac/ I am trying to use Scanline through a PHP script using shell_exec(); the same way that I…
user1145643
  • 896
  • 5
  • 15
  • 26
0
votes
1 answer

Simultaneous Ellipse Scan Conversion

Problem: Given two points (lying on an ellipse) (x1,y1) and (x2,y2) in the first quadrant. Scan convert the ellipse/elliptical arc from both ends simultaneously/point plotting should begin from both the ends at the same time. My solution so far: I…
Ramit Sawhney
  • 31
  • 1
  • 9
0
votes
1 answer

How to use segment tree and scanline

Given 300000 segments. Consider any pair of segments: a = [l1,r1] and b = [l2,r2]. If l2 >= l1 and r2 <= r1 , it is "good" pair. If a == b, it is "bad" pair. Overwise, it is "bad" pair. How to find number of all "good" pairs among given segments…
J.Exactor
  • 1
0
votes
0 answers

How to dynamically fill color in a polygon in OpenGL

I'm creating a program in OpenGL using glut in which the user can draw lines or circles on the screen by selecting the appropriate option and dragging the left mouse button on the screen. Also, I want the user to be able to fill color in the polygon…
Mandeep Beniwal
  • 31
  • 1
  • 4
0
votes
0 answers

Implementing Scanline Algorithm

I'm trying to implement a scan line filling algorithm for random triangles given 3 points as arrays and a color. I'm getting some weird results. Please ignore the optimization of the code, I'm just trying to get it to work and then try to optimize…
Yani Mihaylov
  • 1
  • 1
0
votes
1 answer

getting image color information from both RGB32 and indexed type images

I am trying to access the image colors in a QImage. The method that I found most in docs is based on the scanline function... I tried and it worked... on RGB32 images. I had surprising - and unpleasant results when using the exact method to get…
Thalia
  • 13,637
  • 22
  • 96
  • 190
0
votes
2 answers

Scanline in YUV image format

Can some body explain to me that what is scanline mean in general and what does it mean in YUV color format? Some explanation with some example will be great. Thanks A.S
Madu
  • 4,849
  • 9
  • 44
  • 78
0
votes
1 answer

How to "flush" changes to a bitmap's ScanLine

I'm currently trying to add mirroring to our RotateBitmap routine (from http://www.efg2.com/Lab/ImageProcessing/RotateScanline.htm). This currently looks like this (BitMapRotated is a TBitmap) in pseudo-code: var RowRotatedQ: pRGBquadArray; //4…
Uli Gerhardt
  • 13,748
  • 1
  • 45
  • 83
0
votes
1 answer

scan-line filling, differentiating between intersection points and peaks

I'm applying the scan-line algorithm to fill in a randomly generated continent-like shape. The main problem I'm having is when the line intersects a point that is a tip. I created some images to help visualize…
user1801501
  • 1
  • 1
0
votes
1 answer

Fastest way to implement z-buffering for a software renderer?

I'm implementing a javascript software renderer (for academic purposes). It handles representing a 3d object as triangles, and handles Perspective Projection from 3d space to 2d space. Until now, I used the lineTo and fillRect to represent the…
Spectraljump
  • 4,189
  • 10
  • 40
  • 55
0
votes
1 answer

The order of bytes in a BMP scanline

I'm unsure as to whether it's BGR, then a NULL, or is it BGRBGR-> and then NULLs at the end to pad the width to a multiple of 4? Thanks for your time.
Erkling
  • 509
  • 4
  • 16
-1
votes
1 answer

c++ opengl scan line algorithm

Given the code (taken from Scan-line fill OpenGL/GLUT algorithm in C++): void scanfill(float x1,float y1,float x2,float y2,float x3,float y3,float x4,float y4) { int le[500],re[500],i,j; for(i=0;i<500;i++) le[i]=500,re[i]=0; …
JamesCs15
  • 27
  • 6
1 2
3
4