Does canvas support PNG alpha? Im having some issues with a few PNGs that I've added to the canvas. The edges of the images are black and jagged as if no alpha channel exists or is being recognized.
PNG Transparency on Canvas
12.3k Views Asked by Rigil At
2
There are 2 best solutions below
0
adrield
On
Use clearRect() or fillRect() before redrawing the PNG image, if you are doing it in a requestAnimationFrame or setInterval loop.
I stumbled upon this question as I had a similar problem, but my image was already at 24-bit. Had a requestAnimationFrame loop redrawing the PNG image to the canvas and (as you said) as they overlapped, the result was this "burned" edges where it should have the alpha "fade-out" transparency.
Simply by cleaning the area before calling drawImage, you can prevent that image to be rendered over itself.
Related Questions in CANVAS
- Random number generator in Python Canvas
- When I use electron js and canvas in node js, I get a rebuild module error
- How to set an individual mouse scroll on two different canvases that are connected to separate frames but the frames are one on top of eachother?
- Positioning for sliders and canvas
- How to perfectly align textarea and canvas fillText
- Rust Ownership Challenges in Drawing Application: Need Assistance with Code Section
- Zoom In/Out particular Object with Touch in Fabric JS
- How to send a big array to a client faster
- Android: How to scale a bitmap to fit the screen size using canvas?
- How can i resize canva and send resized data to database?
- Given a convex polygon as a set of edges how to fill the area inside depending on the distance to the closest edge
- SigmaJS: Create a snapshot of "sigma-containter"
- Draw local image on canvas using react-native-canvas
- Rotating multiple objects around the origin (JavaScript Canvas)
- How to proper rotate object with a 45-degree angle using OrbitControls?
Related Questions in PNG
- How change path to my new generated webp image in index.html?
- Python canvas save drawing problem with postscript sizes
- Serialize 4 png Images into a Flatbuffer Array
- How can I write the first bytes of a .png image in Java when only signed bytes are supported?
- Oscilloscope graph data cannot be converted to graphs
- Hide elements of htmlwidget plot before saving as PNG
- Is there a way to convert emf/wmf files to png/jpg in python?
- Could converting a JPG to PNG or PPM be a good idea?
- What is the difference between converting PNG images to JPEG using convertio.co
- Blender image sequence (png) to Unity
- How to plot multiple VennDiagrams in png file from within a function in R
- Visio VBA export to PNG in high resolution?
- How we can download an image with PNG format in Power Apps?
- cypress mochawesome reporter screenshot as base64
- How can I display a Base64 encoded image in Android using Coil?
Related Questions in TRANSPARENCY
- Blender to Unity Vertex Color (Alpha) Data Doesn't Work
- How to fetch the data of a PNG PHAsset, which is cropped or adjusted?
- Models using Unity URP shader and transparency are overlapping themselves
- Colorize, Transparent and Move Selected Entities on Xbim Control
- Set transparent fill for box plots using px.box
- How to set p5.js alpha channel transparency in a shader?
- Knock-out transparency group, TikZ and SVG
- TextLabels not changing to Visible = false to Visible = true
- Keep transparency after merging 2 videos
- Transparency probleme on my c++ windows.h
- Android: TextView transparent png as background resource not working
- Hiding widgets in a QMainWindow layout with a translucent background on macOS
- Unity Built-in shader, cutout + transparent
- Magick -depth 16 command changes alpha channel data
- How can I create a tkinter python object to be 50% opacity?
Related Questions in ALPHA
- Blender to Unity Vertex Color (Alpha) Data Doesn't Work
- How to calculate pooled Cronbach's Alpha after multiple imputation
- PyQT5 QAbstractVideoSurface: Play Video with alpha channel (on windows)
- How do I control the alpha of a geom_point fill?
- How to improve color layer mask to have mid tones?
- how do I change the alpha channel along a path in cairo?
- Compare theoretical and empirical alpha
- REST API to identify Stable Maven Version of any Maven dependency
- How to set p5.js alpha channel transparency in a shader?
- How to add transparency values correctly?
- THREE.js GLTFLoader alpha does not show transparency(shows white background instead)
- "Replacement has x rows" error in code that previously worked (geom_sf/gganimate/shadow_mark)
- overlapping colors in ggplot geom_point
- Three Fiber not showing transparent png texture
- Is the alpha flag for the canvas tag getContext function advisory only?
Related Questions in COLOR-CHANNEL
- How to fix the problem on converting ShaderToy color to Processing?
- Display only one channel in a html img as greyvalue image
- OpenCV giving an opposite color order (BGR - RGB) upon reading
- Which channel I can use to convert hist image to color image?
- Using PIL to adjust color saturation of list of images. I receive no errors but the output does not reflect my changes
- Converting TYPE_INT_RGB to TYPE_BYTE_GRAY image creates wrong result
- Saving a single channel of a bitmap image to a file
- Extract hue channel from HSV image in Pillow
- Why applying the same channel thrice results in a black and white image?
- Convert Color32 array to byte array to send over network
- cv2.imwrite changes color when saving from np.array to JPG
- Converting RGBA to YUV422 format using c++ - not getting proper output
- GStreamer - swap color channels of RGB-video
- AS3 Bitmap black and white - for compression reasons
- Shifting color channels without drawing each channel separately?
Trending Questions
- UIImageView Frame Doesn't Reflect Constraints
- Is it possible to use adb commands to click on a view by finding its ID?
- How to create a new web character symbol recognizable by html/javascript?
- Why isn't my CSS3 animation smooth in Google Chrome (but very smooth on other browsers)?
- Heap Gives Page Fault
- Connect ffmpeg to Visual Studio 2008
- Both Object- and ValueAnimator jumps when Duration is set above API LvL 24
- How to avoid default initialization of objects in std::vector?
- second argument of the command line arguments in a format other than char** argv or char* argv[]
- How to improve efficiency of algorithm which generates next lexicographic permutation?
- Navigating to the another actvity app getting crash in android
- How to read the particular message format in android and store in sqlite database?
- Resetting inventory status after order is cancelled
- Efficiently compute powers of X in SSE/AVX
- Insert into an external database using ajax and php : POST 500 (Internal Server Error)
Popular # Hahtags
Popular Questions
- How do I undo the most recent local commits in Git?
- How can I remove a specific item from an array in JavaScript?
- How do I delete a Git branch locally and remotely?
- Find all files containing a specific text (string) on Linux?
- How do I revert a Git repository to a previous commit?
- How do I create an HTML button that acts like a link?
- How do I check out a remote Git branch?
- How do I force "git pull" to overwrite local files?
- How do I list all files of a directory?
- How to check whether a string contains a substring in JavaScript?
- How do I redirect to another webpage?
- How can I iterate over rows in a Pandas DataFrame?
- How do I convert a String to an int in Java?
- Does Python have a string 'contains' substring method?
- How do I check if a string contains a specific word?
If you put a 24-bit PNG with alpha on the canvas it understands it.
https://developer.mozilla.org/en-US/docs/Web/Guide/HTML/Canvas_tutorial/Using_images
Maybe your PNGs are not clean, i.e. have non-transparent regions at the borders?