All Questions
Tagged with image-processing images
19
questions
0
votes
1
answer
51
views
Which compression modes of convert of imagemagick are lossless (with -quality 100)?
On my Debian 12,
$ convert -list compress
B44A
B44
BZip
DXT1
DXT3
DXT5
Fax
Group4
JBIG1
JBIG2
JPEG2000
JPEG
LosslessJPEG
Lossless
LZMA
LZW
None
Piz
Pxr24
RLE
RunlengthEncoded
WebP
ZipS
Zip
Zstd
Which ...
- 149
0
votes
4
answers
1k
views
How do we search for files which contain a specific word and end in a specific file-type suffix?
How do we use Microsoft Windows PowerShell and Regular Expressions (Regex) in order to find all of the pictures (image files) on a computer such that the file name contains the word "dog".
...
2
votes
1
answer
1k
views
Fast Stone Image Viewer - Creating one image out of multiple images
I was wondering if there's a functionality within Fast Stone Image Viewer that allows you to "glue" several images together into a single image as sort of an image grid while keeping the ...
- 131
1
vote
0
answers
421
views
Extracting text from animated GIF file
I have a GIF file that shows a scrolling down through a table. That table has data that I need to extract. Here is how the file looks like,
BTW, I have video files that show the same. With extensions ...
- 191
1
vote
1
answer
602
views
Drawing text on a gif while preserving transparency [FFMPEG]
Using the regular method, input > drawtext seems to remove transparency for GIFs and messes with the coloring
ffmpeg -i test.gif drawtext=text='Test':fontcolor=red:fontsize=24 output.gif
I've ...
0
votes
1
answer
458
views
Bulk convert image-data URIs to images
I have a text file of 391 image-data URIs, one on each line. I need to batch-convert them all to images, named according to their sequence (i.e. image001.png, image002.png or similar).
What do people ...
- 395
0
votes
1
answer
12k
views
How to calculate the size of an image?
How many images of size 800×600 with 8-bit gray level can be stored in 512 MB of storage?
- 3
2
votes
2
answers
2k
views
How can I enhance the gray text on scanned crumpled receipts?
Consider the following snippet of a receipt I've scanned:
usually when I scan receipts I manage to separate the text and the background using something like a color-range selection tool, selection ...
- 9,852
1
vote
1
answer
119
views
Images with blurring in the center
I was trying to remember the name of a specific effect/coding which is applied to images, where the center of image (or any part) is clear and gradually quality decreases in a circular manner. What is ...
- 539
0
votes
1
answer
368
views
Removing background from image with transparent foreground
I have an image which has a constant color background.
There are objects drawn in front which may have transparency.
Is there a way, algorithm-wise, to remove the background from the image so that I ...
- 113
0
votes
1
answer
53
views
Substracting colors and extracting transparency values
Lets say a picture was made to semi-transparent and added on a flat background color. The original picture, background color and result(mixture) is known. But, that added transparency(alpha value) is ...
- 223
7
votes
3
answers
18k
views
How to convert an image from perspective projection to orthographic projection?
Sometimes you want to make a 2D image on the computer from a real life 2D image, but for whatever reason you can't get a straight, front-on view of the image.
Say it's a billboard and you can only ...
- 4,593
2
votes
1
answer
566
views
How to draw pixel-perfect geometric shapes and patterns?
When designing user interfaces, games and other visual applications, very often you have to have an image with a well defined geometric pattern. Some examples:
A placeholder image of given size with ...
- 135
1
vote
1
answer
1k
views
Converting JPG to BMP, then back to JPG without loss
Someone has converted a number of JPG's to BMP's, and then to PNG, under the assumption that it will "increase quality". Of course, it doesn't, as once you've introduced lossy compression you can ...
- 1,199
4
votes
2
answers
15k
views
Getting the predominant colour in an image?
Is it possible to get the predominant colour in an image from the command line? Ideally I'd like it back as hex or RGB.
I thought it might be possible to do this with imagemagick's identify command, ...
- 163