I have many images (plots) saved as png from another script:
x1.png
x2.png
x3.png
x4.png
y1.png
y2.png
etc. I am trying to make a gif of these, which I have done successfully in magick. However, this loops through 1 image per frame. I am trying to load 4 images at a time, and stitch them together on a panel, and create a gif of these panels.
I have successfully created a gif of these images.
However, I want to load 4 images at a time, and then form these into a gif.
y <- (list.files(path='foo/bar/', pattern = '*1.png', full.names = TRUE))
plot(y[1]) # does nothing
How can I load or display 4 pngs at a time in one panel?
I can do this usually by using:
par(mfrow=c(2,2))
plot(a)
plot(b)
plot(c)
plot(d)
however I am using magick to load pngs (of plots, but I obviously can't treat them as regular plots)
img1 <- magick::image_read("foo/bar/x1.png")
plot(img1) # does nothing
print(img1) # displays img 1 as a plot, and prints some details in the output window.
I'm sure I could rewrite my other code to display 4 plots, and save them as 1 png, but I am trying to write a small separate script to load these pre-existing images, and stitch the pngs together. Is this possible using par(mfrow=c(2,2))?
I'm sure I'm missing a great many simple things. Thank you all for your time.
You can do that in ImageMagick using montage. For example
montage lena.jpg mandril3.jpg zelda1.jpg peppers.jpg -tile 2x2 -geometry +0+0 montage.gif
To run ImageMagick commands (or any terminal code) in R, you just have to enclose it in quotes and pass that to the function system().
system("montage lena.jpg mandril3.jpg zelda1.jpg peppers.jpg -tile 2x2 -geometry +0+0 montage.gif")
Related
I created a super large grid and now I cannot view the image.
Is there a way for me to save it as png or similar and use a magnifying glass to see each facet?
I have tried viewing it in the R itself, saving with ggsave, saving with cairo and exporting.
Here, I show you my script and the image
#install.packages("ggh4x")
library(ggh4x)
qPCR_data$Treatment <- factor(qPCR_data$Treatment, levels =c("NW","S","NS","Ec6","Ec7"))
qPCR_data$Wing <- factor(qPCR_data$Wing, levels =c("Wounded","Control"))
qPCR_grid <- ggplot(qPCR_data, aes(x=factor(SampleID), y=CtGene, colour=Replicate,group=Gene)) +
geom_point(aes(fill=Gene),position=position_dodge(0.3))+
facet_nested(TimePoint~Wing+Treatment)
ggsave("qPCR_grid2.png", plot=qPCR_grid)
qPCR_grid
I have 3 R plots saved as pdf files (upper_left.pdf, upper_right.pdf, lower.pdf) as vector graphic and want to make a one-page pdf file and arrange them on it as follows:
What I have tried already
I have tried reading the pdf's using magick::image_read_pdf and appending them using magick::image_append. More specifically,
library(magick)
panel.ul <- image_read_pdf("upper_left.pdf")
panel.ur <- image_read_pdf("upper_right.pdf")
panel.l <- image_read_pdf("lower.pdf")
whole <- c(panel.ul, panel.ur) %>%
image_append() %>%
c(panel.l) %>%
image_append(stack = TRUE)
The first issue is magick::image_read_pdf imports the plot as png (if I'm right, not vector graphic though).
magick::image_append also 'works' and gives me what I want in viewer pane (in RStudio, next to Help).
I then try to save them using export::graph2pdf(whole), but it gives me a blank page.
So, if I am to use magick, there are two issues that need to be solved:
importing plots as vector graphic objects (do not know the technical term in R)
Exporting the stacked plot to a vector pdf file.
How can I solve it? thanks in advance.
You're basically done. You only need to add
plot(whole) # plot the external object generated in ImageMagick to R's plotting device
savePlot(type = "pdf") # saves the current plotting device to a pdf file.
You will find your plot in your workoing directory called "Rplot.pdf".
savePlot has many options to customize your pdf output. Make sure to check ?savePlot.
To recreate your scheme from above youll need to temporarily save the upper panel as a separate pdf before you paste it to on top of the lower panel:
whole2 <- image_append(c(panel.ul, panel.ur))
plot(whole2)
savePlot("whole2.pdf", type = "pdf")
If the upper and lower panel do not look proportionate you can use the heght and width parameters of savePlot to adjust the size of the first pdf.
panel.upr <- image_read_pdf("whole2.pdf")
final <- image_append(c(image_append(panel.upr),panel.l), stack = TRUE)
plot(final)
savePlot("final.pdf", type = "pdf")
I want to read 12 images at a time in R.
I don't know how to do it. I am complete new to working on images in R.
How can I read couple of images from a folder in my system?
I am using windows10 operating system. RAM 8 gb. CORE i5 processor.
GPU is Intel(R) HD Graphics 620.
I am able to read only single image in R and that image is displaying as numeric values. I tried to convert it into raster format and then tried to print image to view the image. But I am still finding the color codes in values but not the image in print.
Can anyone help me on this?
Thanks a lot.
install.packages("magick")
library(magick)
install.packages("rsvg")
install.packages("jpeg")
library(jpeg)
img <- readJPEG("C:/Users/folder/Abc.jpg", native = FALSE)
img1 <- as.raster(img, interpolate = F)
print(img1)
I want to read couple of images at a time into R console and want to view or print images.
The suggested duplicate gives you the basics for how to read in a number of files at once, but there are a few potential gotchas, and it won't help you with displaying the images.
This first bit is purely to set up the example
library(jpeg)
library(grid)
# Create a new directory and move to it
tdir <- "jpgtest"
dir.create(tdir)
setwd(tdir)
# Copy the package:jpeg test image twice, once as .jpg and once as .jpeg
# to the present working directory
file.copy(system.file("img", "Rlogo.jpg", package="jpeg"),
to=c(file.path(getwd(), "test.jpg"), file.path(getwd(), "test.jpeg")))
Then we can list the files, either using a regex match, or choose them interactively, then read and store the images in a list.
# Matches any file ending in .jpg or .jpeg
(flist <- list.files(pattern="*\\.jp[e]?g$"))
# Interactive selection
flist <- file.choose()
jpglist <- lapply(flist, readJPEG)
To display the images I tend to use grid, but there are a number of alternatives.
grid.raster(jpglist[[1]], interpolate=FALSE)
Remove temporary directory
setwd("..")
unlink(tdir)
I've made different plots (more than a hundred) for a project and I haven't capture them on the way (yes it's bad , i know). Now, I need to save them all at once but without running again my script (which takes hours). Is there a way to do so within Rstudio ?
Edit: All the plot are already there and I don't want to run them again.
In RStudio, every session has a temporary directory that can be obtained using tempdir(). Inside that temporary directory, there is another directory that always starts with "rs-graphics" and contains all the plots saved as ".png" files. Therefore, to get the list of ".png" files you can do the following:
plots.dir.path <- list.files(tempdir(), pattern="rs-graphics", full.names = TRUE);
plots.png.paths <- list.files(plots.dir.path, pattern=".png", full.names = TRUE)
Now, you can copy these files to your desired directory, as follows:
file.copy(from=plots.png.paths, to="path_to_your_dir")
Additional feature:
As you will notice, the .png file names are automatically generated (e.g., 0078cb77-02f2-4a16-bf02-0c5c6d8cc8d8.png). So if you want to number the .png files according to their plotting order in RStudio, you may do so as follows:
plots.png.detials <- file.info(plots.png.paths)
plots.png.detials <- plots.png.detials[order(plots.png.detials$mtime),]
sorted.png.names <- gsub(plots.dir.path, "path_to_your_dir", row.names(plots.png.detials), fixed=TRUE)
numbered.png.names <- paste0("path_to_your_dir/", 1:length(sorted.png.names), ".png")
# Rename all the .png files as: 1.png, 2.png, 3.png, and so on.
file.rename(from=sorted.png.names, to=numbered.png.names)
Hope it helps.
Although this discussion has been inactive for a while, there are some persons, like myself, who still come across the same problem, and the other solutions don't really seem to even get what the actual question is.
So, hands on. Your plot history gets saved in a variable called .SavedPlots. You can either access it directly, assign it to another variable in code or do the latter from the plots window.
# ph for plot history
ph <- .SavedPlots
In R 3.4.2, I could index ph to reproduce the corresponding plot in a device. What follows is rather straightforward:
Open a new device (png, jpeg, pdf...).
Reproduce your plot ph[index_of_plot_in_history].
Close the device (or keep plotting if it is a pdf with multiple pages).
Example:
for(i in 1:lastplot) {
png('plotname.png')
print(ph[i])
dev.off()
}
Note: Sometimes this doesn't happen because of poor programming. For instance, I was using the MICE package to impute many datasets with a large number of variables, and plotting as shown in section 4.3 of this paper. Problem was, that only three variables per plot were displayed, and if I used a png device in my code, only the last plot of each dataset would be saved. However, if the plots were printed to a window, all the plots of each dataset would be recorded.
If your plots are 3d, you can take a snapshot of all your plots and save them as a .png file format.
snapshot3d(filename = '../Plots/SnapshotPlots.png', fmt = 'png')
Or else, the best way is to create a multi-paneled plotting window using the par(mfrow) function. Try the following
plotsPath = "../Plots/allPlots.pdf"
pdf(file=plotsPath)
for (x in seq(1,100))
{
par(mfrow = c(2,1))
p1=rnorm(x)
p2=rnorm(x)
plot(p1,p2)
}
dev.off()
You can also use png, bmp, tiff, and jpeg functions instead of pdf. You can read their advantages and disadvantages and choose the one you think is good for your needs.
I am not sure how Rstudio opens the device where the plot are drawn, but I guess it uses dev.new(). In that case one quick way to save all opened graphs is to loop through all the devices and write them using dev.print.
Something like :
lapply(dev.list(),function(d){dev.set(d);dev.print(pdf,file=file.path(folder,paste0("graph_",d,".pdf"))})
where folder is the path of the folder where you want to store your graph (could be for example folder="~" if you are in linux and want to store all your graph in your home folder).
If you enter the following function all that will follow will be save in a document:
pdf("nameofthedocument.pdf")
plot(x~y)
plot(...
dev.off()
You can also use tiff(), jpg()... see ?pdf
A lot of the time, I find it very useful to output graphics with pdf() as it allows me to scroll through pages and observe subtle differences (e.g. the page numbers may correspond to a particular parameter in a simulation).
Sometimes if the plot is quite packed with information, the fact that the PDF is a vector graphic means that it takes a long time to load in a PDF reader and is useless for scrolling through pages. I could plot with png(), but this would result in many image files.
My ideal solution would be to have a device that will plot a bitmap graphic (e.g. PNG) to a PDF.
I have read that cairo_pdf() outputs to a bitmap sometimes? Or I could write something that outputs to PNG, then combines these all together into a PDF?
Any other thoughts? Or does anyone have a solution for this already?
UPDATE: have now added method based on readPNG() as suggested in comments above. It's a bit slower (3s vs 9s) and seems to result in slightly larger file sizes than ImageMagick. rasterImage() interpolation makes no difference to filesize or timing, but alters the appearance slightly. If it's FALSE, then it looks the same as ImageMagick
I have just come up with the following solution using ImageMagick. It's not perfect, but it seems to work well so far.
png2pdf <- function(name=NULL,removepngs=TRUE,method="imagemagick",pnginterpolate=FALSE){
# Run the png() function with a filename of the form name%03d.png
# Then the actual plotting functions, e.g. plot(), lines() etc.
# Then dev.off()
# Then run png2pdf() and specify the name= argument if other pngs exist in the directory
# Need to incorporate a way of dealing with non-square plots
if(is.null(name)){
names <- list.files(pattern="[.]png")
name <- unique(sub("[0-9][0-9][0-9][.]png","",names))
if(length(name)!=1) stop("png2pdf() error: Check filenames")
}else{
names <- list.files(pattern=paste0(name,"[0-9][0-9][0-9][.]png"))
}
# Can change this to "convert" if it is correctly in the system path
if(method=="imagemagick"){
cmd <- c('C:\\Program Files\\ImageMagick-6.9.0-Q16\\convert.exe',names,paste0(name,".pdf"))
system2(cmd[1],cmd[-1])
}else if(method=="readPNG"){
library(png)
pdf(paste0(name,".pdf"))
par(mar=rep(0,4))
for(i in 1:length(names)){
plot(c(0,1),c(0,1),type="n")
rasterImage(readPNG(names[i]),0,0,1,1,interpolate=pnginterpolate)
}
dev.off()
}
if(removepngs) file.remove(names)
}