I am trying to download the Feynman lectures using wkhtmltopdf. This is the command line that I use:
wkhtmltopdf.exe http://www.feynmanlectures.caltech.edu/I_44.html --javascript-delay 20000 --no-stop-slow-scripts ./out/I_44.pdf
However the MathJAX formula are rendered too small. Here is a picture:
How I can enlarge the rendered equations?
In this topic the suggested solution (as I understand it) would be to add
MathJax.Hub.Config({
CommonHTML: {
minScaleAdjust: 100,
}
});
to the HTML.
But of course downloading the HTML file and modify it before passing it to wkhtmltopdf would be too cumbersome. I would prefer an easier solution if possible.
Try using
wkhtmltopdf.exe http://www.feynmanlectures.caltech.edu/I_44.html --run-script 'MathJax.Hub.Config({"HTML-CSS": {scale: 200}}); MathJax.Hub.Queue(["Rerender", MathJax.Hub], function () {window.status="finished"})' --window-status finished --no-stop-slow-scripts ./out/I_44.pdf
This will set the scaling factor for the math and re-render it at that size. It also uses the window.status variable to synchronize the page capture with MathJax so that the capture occurs immediately after MathJax finishes (rather than waiting for an arbitrary delay).
Related
This is more of a feature request. I am easily able to generate the PNG by calling toDataURL on the returned canvas. But the quality of the image is rather blurry/poor. I did some googling & found out that by default it just returns an image at 96 dpi. And there doesnt seem to be a standard way of improving this. Also the toDataURLHD is experimental and does not work any ways.
Is there any way html2canvas can return an image at a higher resolution? Or even if it can provide a way to get the DOM being rendered, I can use some library that uses the DOM (with all the computed styles applied to it) and then generate whatever image I want.
I am unable to comment so writing answer. #shiv probably you should look the quesiton setting canvas toDataURL jpg quality
In Raphael you can load up images in the following manner:
var image_one=paper.image("some_url", x,y,width,height);
But the thing is that I am splicing the image, and I need several of those cuts, preferably without reloading the original image. That is because loading up only a single large image via http is faster than many small. Apparently there is some overhead in each upload that can become quite substantial.
But anyways, how can I make a copy of a Raphael image, after it has been loaded into ram?
I have already tried:
var image_two=image_one;
But it seems like that is only creating another link to the image.
This kind of internal copying is done via Raphael's .clone(), which is as simple as this:
var newElem = oldElem.clone();
Element.clone() works on elements including paths, images, rects, circles... but not sets.
Here's a simple demo - play around with splicing as desired.
http://jsbin.com/ufayuw/1/edit
If you want the clone to be hidden until it is needed, hide it with .hide()
I have a local image that I would like to include in an .Rmd file which I will then knit and convert to HTML slides with Pandoc. Per this post, this will insert the local image :
Is there a way to modify this code to also set the image size?
The question is old, but still receives a lot of attention. As the existing answers are outdated, here a more up-to-date solution:
Resizing local images
As of knitr 1.12, there is the function include_graphics. From ?include_graphics (emphasis mine):
The major advantage of using this function is that it is portable in the sense that it works for all document formats that knitr supports, so you do not need to think if you have to use, for example, LaTeX or Markdown syntax, to embed an external image. Chunk options related to graphics output that work for normal R plots also work for these images, such as out.width and out.height.
Example:
```{r, out.width = "400px"}
knitr::include_graphics("path/to/image.png")
```
Advantages:
Over agastudy's answer: No need for external libraries or for re-rastering the image.
Over Shruti Kapoor's answer: No need to manually write HTML. Besides, the image is included in the self-contained version of the file.
Including generated images
To compose the path to a plot that is generated in a chunk (but not included), the chunk options opts_current$get("fig.path") (path to figure directory) as well as opts_current$get("label") (label of current chunk) may be useful. The following example uses fig.path to include the second of two images which were generated (but not displayed) in the first chunk:
```{r generate_figures, fig.show = "hide"}
library(knitr)
plot(1:10, col = "green")
plot(1:10, col = "red")
```
```{r}
include_graphics(sprintf("%sgenerate_figures-2.png", opts_current$get("fig.path")))
```
The general pattern of figure paths is [fig.path]/[chunklabel]-[i].[ext], where chunklabel is the label of the chunk where the plot has been generated, i is the plot index (within this chunk) and ext is the file extension (by default png in RMarkdown documents).
Un updated answer: in knitr 1.17 you can simply use
{width=250px}
edit as per comment from #jsb
Note this works only without spaces, e.g. {width=250px} not {width = 250px}
You can also read the image using png package for example and plot it like a regular plot using grid.raster from the grid package.
```{r fig.width=1, fig.height=10,echo=FALSE}
library(png)
library(grid)
img <- readPNG("path/to/your/image")
grid.raster(img)
```
With this method you have full control of the size of you image.
Here's some options that keep the file self-contained without retastering the image:
Wrap the image in div tags
<div style="width:300px; height:200px">
</div>
Use a stylesheet
test.Rmd
---
title: test
output: html_document
css: test.css
---
## Page with an image {#myImagePage}
test.css
#myImagePage img {
width: 400px;
height: 200px;
}
If you have more than one image you might need to use the nth-child pseudo-selector for this second option.
If you are converting to HTML, you can set the size of the image using HTML syntax using:
<img src="path/to/image" height="400px" width="300px" />
or whatever height and width you would want to give.
Had the same issue today and found another option with knitr 1.16 when knitting to PDF (which requires that you have pandoc installed):
{width=70%}
This method may require that you do a bit of trial and error to find the size that works for you. It is especially convenient because it makes putting two images side by side a prettier process. For example:
{width=70%}{width=30%}
You can get creative and stack a couple of these side by side and size them as you see fit. See https://rpubs.com/RatherBit/90926 for more ideas and examples.
Another option that worked for me is playing with the dpi option of knitr::include_graphics() like this:
```{r}
knitr::include_graphics("path/to/image.png", dpi = 100)
```
... which sure (unless you do the math) is trial and error compared to defining dimensions in the chunk, but maybe it will help somebody.
The knitr::include_graphics solution worked well for resizing the figures, but I was unable to figure out how to use it to produce side-by-side resized figures. I found this post useful for doing so.
I've got wkhtmltopdf working with a header and footer image, and everything spaced well. But the task is to use a full page background image which looks like a sort of frame, with the page text in the center. I thought I could place this in the header, but it doesn't work - maybe the use of a full page header doesn't make sense here.
(These are multi-page documents, which could be of any length).
Any ideas of how to do this?
Thanks in advance.
John
I have a similar problem, this is what I understood so far:
It's not possible to center the text vertically on the page simply via CSS+wkhtmltopdf on a multi-page document (might find some complex javascript stuff, but it wasn't worth in my case);
since wkhtmltopdf uses webkit, and webkit doesn't support #page rules, it's not possible to define a "paged" background via CSS
Hence what? You will need a little hack and use pdftk
1. In your CSS define:
body {
background: white;
}
(if you have a body tag in your header.html and footer.html make sure that rule applies to them as well)
2. Create a one-page pdf with your background image (using the same page size as your final pdf)
3. Install pdftk and from command line:
$ pdftk yourfile.pdf background background.pdf output yourfile_b.pdf
4. Enjoy :)
You can use a solution BASED on webkit, like HTM2PDF - you'll be able to add a feature called 'stationary' where you can integrate any image as a full page background.
more info at the documentation from the API page
I'm trying to text-wrap floating images in LaTeX, using code like the following:
\begin{wrapfigure}{R}{0.5\textwidth}
\begin{center}
\includegraphics{images/image.png}
\caption{This is the caption.}
}
\label{fig:image1}
\end{center}
\end{wrapfigure
This works fine most of the time (creating an image that floats on the right-hand side), but sometimes LaTeX does not properly clear after the image, and it leaves an open column for another page or two. How does one remedy this, or ideally, does LaTeX have a function similar to clear: both in CSS?
There is the \clearpage command, but it's not appropriate when there's no natural place to break to a new page near the image.
You might try to manually set the height of the figure using the optional argument of wrapfigure
\begin{wrapfigure}[lineheight]{alignment}{width}
where lineheight is the number of text lines which shall wrap around the image.
I still don't have a good answer to this question, but the solution for now is to not use wrapfigure at all. Using only figure solves the problem of open columns, but it's not the most ideal solution. Any other answers are still welcome, but I'll post my half-way solution here for those who might also need it:
\begin{figure}
\begin{center}
\includegraphics{images/image.png}
\caption{This is the caption.}
\end{center}
\label{fig:image1}
\end{figure}