I'm trying to convert the image found here pgm image to jpg but I can't. I've tried the answer of the question found here but it didn't work. So, if anyone could please advise.
The problem is in your file-header:
Pf 640 480 9757
According to Wikidepida and this man page your file should use P2 (for the graymap) instead of Pf (which seems to be invalid in all cases):
P2 640 480 9757
With that little change (made in a text editor) your file opens fine.
If you need more faces use the Cambridge's database
And do it like in your link.
$> im = imread( 'file.pgm' );
$> imwrite( im , 'nameForJpg.jpg');
And that's it!
Good Luck!
Live long and prosper!
Related
I am trying to convert a high resolution image (30in width x 60in height) to a pdf file in MATLAB. I tried print, exportgraphics, and couple scripts online but I keep getting low quality output. I also tried setting the resolution to 300dpi but it didnt work. Please if you have any suggestions, share with me and I will test. Many thanks!
Image file used (renamed to map.png): https://upload.wikimedia.org/wikipedia/commons/thumb/d/de/Political_map_of_the_World_%28January_2015%29.svg/9444px-Political_map_of_the_World_%28January_2015%29.svg.png
MATLAB commands used:
world=imread('map.png');
imshow(world)
exportgraphics(gcf,'world.pdf','ContentType','vector','Resolution',300)
#Texts in picture is blurry
print -dpdf 'world.pdf'
#Texts in picture is still blurry
exportfig(gcf, 'world.pdf', 'format','pdf','Resolution', 300,'Renderer', 'painters');
#this is a script from the MATLAB file exchange. Texts still blurry
I managed to do it by importing pdfbox (java) and importing the image as a bufferedimage then creating a document with pdmodel.PDDocument then adding a page with a custom size using the bufferedimage.getWidth and same for length then I streamed the bufferedimage to the page and saved the document to a pdf file. The code is on my work PC if anyone is interested I will copy it here.
I have a PDF of building schematics. I would like to load it into MATLAB, and visualize the image via a GUI, so I can measure distances and such for some calculations.
I have no idea if this is even possible?
Furthermore, the PDF has an embedded scale (i.e. 1 cm = 1 meter). If I can extract this as well, that would be awesome.
I found extractFileText which can be used to extract text, but not much else.
I found the easiest way to do this was to convert the pdf to a image, for example using imagemagick. See this question
If you add an example of the image someone might be able to suggest some ideas for extracting the scale information using image processing.
I am attempting to make a very simple label using Libreoffice Draw v 4.0.2.2. The label has not much more to it than regularly spaced lines of centered text
This image will be printed, and I have a fixed size/ppi requirement to ensure appropriate print quality.
I set the page size to my specs, and layout the text as I desire. The print shop takes several image formats including .tiff and .png. When I export the image, a dialog pops up that asks for the image size/ resolution. The given ppi is very low (~40) and I require a minimum of 180ppi. When I enter this, the image size adjusts itself and results in an image that is far too small.
The only solution that appears to be viable is to explode the page size and the drawing text size so it gets shrunk upon export. This is a very imprecise and illogical feature (bug?) of the program that I really wish is a result of my ignorance.
I found a thread in the mailing list which describes this issue exactly. The only answer that is given is essentially "yes, this is ridiculous and doesn't help anybody".
Can anyone give some advice to this? Or at least shed some light on who might need this "feature"?
There is something off about the Export tool of LibreOffice in general. It has been years since it is broken. Taking a screenshot is an alternative, but obviously you cannot control the resolution.
So, a better work around is exporting to SVG, and then convert the SVG to PNG with Inkscape. Once downloaded, convert the file with the following command:
inkscape -z -e out.png -w 1024 in.svg
If you are in Windows (x64), you will need to indicate the full path:
"C:/Program Files/Inkscape/inkscape.exe" -z -e out.png -w 1024 in.svg
If you install the 32 bit version, this should work:
"C:\Program Files (x86)/Inkscape/inkscape.exe" -z -e out.png -w 1024 in.svg
This can be done from inside Libre Office, there is no need to use any external tool. The Export dialog is very confusing, yes; you have to realize that both size and resolution can be set independently.
Select File -> Export -> choose the desired format. The export dialog should appear.
TAKE NOTE of Width and Height. Set the desired resolution; notice how Width and Height change (?). Don't worry, restore Width and Height to your saved values. And that's it. You get a high resolution image with the desired size and DPI.
Libre Draw (the one I'm using anyway) is a vector drawing app - have you asked the print shop if they can use vector formats like eps, pdf? Most should be able to in my experience. Then resolution becomes irrelevant.
-Terry
I am using tesseract open source engine for OCR to read text from image.
But I didn't get 100% result for a single time. Please give your suggestions about quality improvement for OCR using tesseract.
Thanks
here is how to get best result from tesseract
Please make sure that you have done preprocessing on image. OVR will produce best results for the images which have following properties:
fix DPI (if needed) 300 DPI is minimum
fix text size (e.g. 12 pt should be ok)
try to fix text lines (deskew and dewarp text)
try to fix illumination of image (e.g. no dark part of image
binarize and de-noise image
https://groups.google.com/forum/?fromgroups=#!topic/tesseract-ocr/g5aE_OvgyTU
I want to save a MATLAB figure as PDF, with quality 300 DPI, and centered.
So far I managed to save it, but the image appears cropped. I changed the page type to A3 and kind of solves the problem, but I am looking for something more elegant. I am doing it from the GUI, but maybe from the command line is easier in MATLAB.
Is there any package or script that makes this (fundamental task for publications and papers) a bit easier?
Try using the following command:
print -painters -dpdf -r300 test.pdf
You will, of course, already have to have a file named test.pdf in the current directory.
Some notes on the -commands as well.
-painters: this specifies the use of the painters alogrithm for the exporting.
-dpdf: specifies a vector image, specially a pdf in this case. This is through Ghostscript.
-r300: specifies a 300 dpi resolution. -r400 would be 400 dpi and so on.
On an off note. I tend to just save the figure as a high DPI tiff image and import that tiff into another program where I actually assemble my figure(s) for the paper. I tend to lean towards CorelDraw personally.
I would recommend to check the exportfig package
exportfig(gcf, path_to_file, 'format','pdf','Resolution', 300 )
also, you can check fig package, which is nice to call before the exportfig:
figure
plot(x,y)
fig
exportfig(gcf, path_to_file, 'format','pdf','Resolution', 300 )