I have a sequence of images that are blocks of a larger image, which together make up the whole image. The blocks are the result of splitting the original image along evenly spaced horizontal and vertical lines, so they don't have weird dimensions.
Is there a way to combine them with FFmpeg (or something else like ImageMagick) without re-encoding the images?
This answer suggests the hstack or vstack FFmpeg filter, but my image blocks aren't necessarily the full width or the full height of the original image.
Like this:
Perhaps this could be achieved with multiple FFmpeg commands using hstack or vstack (I'd prefer just one command though). Or with a complex filter?
e.g.
Edit: I tried using filter_complex with FFmpeg:
ffmpeg -i 0.jpg -i 1.jpg -i 2.jpg -i 3.jpg -i 4.jpg -i 5.jpg \
-filter_complex "[0][1]hstack=inputs=2[row 0]; \
[2][3]hstack=inputs=2[row 1];
[4][5]hstack=inputs=2[row 2];
[row 0][row 1][row 2]vstack=inputs=3[out]" \
-map "[out]" -c copy out.jpg
but it can't filter and copy streams at the same time.
You can do that with ImageMagick. However, it will decompress and recompress your jpg files. You will lose some quality.
Unix Syntax for IM 6:
convert \
\( 0.jpg 1.jpg +append \) \
\( 2.jpg 3.jpg +append \) \
\( 4.jpg 5.jpg +append \) \
-append \
mona_lisa.jpg
If using Windows remove the \ from the parentheses and replace the end of line \ with ^.
If using IM 7, replace convert with magick.
I found an interesting patch from 2010 against libjpeg which adds this feature to jpegtran. It won't split blocks, so your images will need to be multiples of 8 or even 16 pixels in each axis.
Unfortunately it's against the libjpeg 6b as distributed for ubuntu10. This includes some patches from 8d and doesn't really correspond neatly to any official libjpeg version (as far as I can see).
You need to download the ubuntu10.04 sources, extract their libjpeg, and patch that. The steps are:
wget http://old-releases.ubuntu.com/releases/releases/10.04/release/source/ubuntu-10.04-src-1.iso
Now open that ISO and pull out the files from ubuntu/pool/main/libj/libjpeg6b. Archive Manager can do this, perhaps there's some scriptable tool as well.
Now run:
# original sources
tar xf libjpeg6b_6b.orig.tar.gz
cd jpeg-6b
# apply ubuntu patches
zcat ../libjpeg6b_6b-15ubuntu1.diff.gz | patch
# apply jpegtran patches
patch < ../append-jpeg6b.patch
./configure
make
sudo make install
That will install the modified jpegtran to /usr/local.
Given 0.jpg and 1.jpg:
You can run it like this:
jpegtran -appright 1.jpg 0.jpg > join.jpg
To make:
Related
I tried to resize a very big image (457 MB and 21600x21600) with the following command
-i test.png -vf scale=320:-1 out.png
but it throws exception saying "Picture size 21600x21600 is invalid". How can I find out the biggest supported resolution by ffmpeg? Is there a way to resize this high resolution image with ffmpeg?
If you want to use ImageMagick it is included in most Linux distros and is available for macOS and Windows.
Your command becomes:
convert test.png -resize 320x result.png
If you are running v7 or newer, use:
magick test.png -resize 320x result.png
If you have lots to do, and you want all the resized images written in a directory called thumbs you can use:
mkdir thumbs
magick mogrify -path thumbs -resize 320x *.png
Alternatively, you may find vips is a lighter-weight installation and does a faster conversion using less memory:
mkdir thumbs
vipsthumbnail -s 320 -o "thumbs/%s.png" image.png
I have a directory of images and need to merge those images horizontally in groups of two, then save the output of each to a new image file:
image-1.jpeg
image-2.jpeg
image-3.jpeg
image-4.jpeg
image-5.jpeg
image-6.jpeg
Using Imagemagick via command line, is there a way to loop through every other image in a directory and run magick convert image-1.jpeg image-2.jpeg +append image-combined-*.jpg?
So the result would be combined pairs of images:
image-1.jpeg image-2.jpeg -> image-combined-1.jpg
image-3.jpeg image-4.jpeg -> image-combined-2.jpg
image-5.jpeg image-6.jpeg -> image-combined-3.jpg
Get them all appended succinctly and in parallel with GNU Parallel and actually use all those lovely CPU cores you paid Intel for!
parallel -N2 convert {1} {2} +append combined-{#}.jpeg ::: *jpeg
where:
-N2 says to take two files at a time
{1} and {2} are the first two parameters
{#} is the sequential job number, and
::: demarcates the start of the parameters
If your CPU has 8 cores, GNU Parallel will run 8 converts at once, unless you specify say 4 jobs at a time by adding -j4.
If you are learning and just finding your way with GNU Parallel add:
--dry-run so you can see what it would do without actually doing anything
-k to keep the outputs in order
So, I mean:
parallel --dry-run -k -N2 convert {1} {2} +append combined-{#}.jpeg ::: *jpeg
Sample Output
convert image-1.jpeg image-2.jpeg +append combined-1.jpeg
convert image-3.jpeg image-4.jpeg +append combined-2.jpeg
convert image-5.jpeg image-6.jpeg +append combined-3.jpeg
On macOS, you can simply install GNU Parallel with:
brew install parallel
If you have thousands, or hundreds of thousands of files, you may run into an error Argument list too long - although this is pretty rare on macOS because the limit is 262,144 characters:
sysctl -a kern.argmax
kern.argmax: 262144
If that happens, you can use this syntax to pipe the filenames in GNU Parallel instead:
find /somewhere -iname "*.jpeg" -print0 | parallel -0 -N2 convert {1} {2} +append combined-{#}.jpeg
If the images are all the same size and orientation, and if your system has the memory to read in all the images in the directory, it can be done as simply as this...
magick *.jpeg -set option:doublewide %[fx:w*2] \
+append +repage -crop %[doublewide]x%[h] +repage image-combined-%02d.jpg
This can be scripted easily using ImageMagick. I could show you how in Unix. But if you have more than 9 images, then you may have to rename with leading zeros, since alphabetically image-10 will come before image-2. You do not mention your IM version or platform and scripting will differ depending upon OS.
Here is a Unix solution. I have images rose-01.jpg ... rose-06.jpg in folder test on my desktop (Mac OSX). Each image has a label under it with its filename so we can keep track of the files.
cd
cd desktop/test
arr=(`ls *.jpg`)
num=${#arr[*]}
for ((i=0; i<num; i=i+2)); do
j=$((i+1))
k=$((i+2))
magick ${arr[$i]} ${arr[$j]} +append newimage_${j}_${k}.jpg
done
Note that arrays start with index 0. So I use j=i+1 and k=i+2 for the images that correspond to 1,2 3,4 5,6 in the filenames from ls in the array.
The result is (newimage_1_2.jpg, newimage_3_4.jpg, newimage_5_6.jpg)
An alternate solution is to montage all the images together two-by-two as an array of 2x3 and then equally crop them into 3 sections vertically. So in ImageMagick, this also works since these images are all the same size.
cd
cd desktop/test
arr=(`ls *.jpg`)
num=${#arr[*]}
num2=`magick xc: -format "%[fx:ceil($num/2)]" info:`
magick montage ${arr[*]} -tile 2x -geometry +0+0 miff:- | magick - -crop 1x3# +repage newimage.jpg
The results are: newimage-0.jpg, newimage-1.jpg, newimage-2.jpg
Ole Tang wrote:
Fails on filenames like My summer photo.jpg
So here is the solution using ImageMagick as modified from my original post.
Images:
rose 1.png
rose 2.png
rose 3.png
rose 4.png
rose 5.png
rose 6.png
OLDIFS=IFS
IFS=$'\n'
arr=(`ls *.png`)
for ((i=0;i<6;i++)); do
echo "${arr[$i]}"
done
IFS=OLDIFS
num=${#arr[*]}
for ((i=0; i<num; i=i+2)); do
j=$((i+1))
k=$((i+2))
magick "${arr[$i]}" "${arr[$j]}" +append newimage_${j}_${k}.jpg
done
This produces:
newimage_1_2.jpg
newimage_3_4.jpg
newimage_5_6.jpg
I am using custom batch script to make resized copies (33% and 66%) of all PNG images in folder. Here is my code:
for f in $(find /myFolder -name '*.png');
do
sudo cp -a $f "${f/%.png/-3x.png}";
sudo convert $f -resize 66.67% "${f/%.png/-2x.png}";
sudo convert $f -resize 33.33% $f;
done
It works fine, except when the original image is indexed. In this case the smaller version of the image is RGB (so even larger file size then original image).
I have try several versions but not worked. One that I guess supposed to sort this out was fallowing:
for f in $(find /myFolder -name '*.png');
do
sudo cp -a $f "${f/%.png/-3x.png}";
sudo convert $f -define png:preserve-colormap -resize 66.67% "${f/%.png/-2x.png}";
sudo convert $f -define png:preserve-colormap -resize 33.33% $f;
done
But it doesn't work.
EDIT:
This is updated co, but it still doesn't work as it supposed to (see the attached image-left is original, right is resized):
for f in $(find /myFolder -name '*.png');
do
sudo cp -a $f "${f/%.png/-3x.png}";
numberOfColors=`identify -format "%k" $f`
convert "$f" \
\( +clone -resize 66.67% -colors $numberOfColors -write "${f/%.png/-2x.png}" +delete \) \
-resize 33.33% -colors $numberOfColors "$f"
done
Original image:
Scaled version:
Use "-sample" instead of "-resize" to preserve the color set. This causes the resizing to be done by nearest-neighbor color selection rather than any kind of interpolation.
Otherwise, the colormap ends up with more than 256 colors and the png encoder can't preserve it, due to the 256-color limit on the size of a PNG PLTE chunk. I cannot guarantee that you'll like the appearance of the result, though.
Also, be sure you are using a recent version of ImageMagick.
I'm not observing this problem with the current release (6.9.3-7). Your script works fine and produces clean -2x and -3x images.
There are several things to address here...
find vs glob
You say you want to process all files in a folder, then you use find which will search down into sub-directories as well. If you just want to process files in the current directory, you can let bash do the globbing directly for you. So, instead of
for f in $(find . -name "*.png"); do
you can just do:
shopt -s nullglob
for f in *.png; do
Performance
You run convert twice and load the original image twice, and that is not very efficient. You can run a single process that loads a single image and resizes to two different sizes and writes both to disk. So, instead of
for ...; do
convert ...
convert ...
done
you can write the following to start one convert, read the image once, clone it in memory and write it out, delete the spare copy in memory and then resize the original image and re-save that.
for ...; do
convert "$f" \
\( +clone -resize 66.67% -write "${f/%.png/-2x.png}" +delete \) \
-resize 33.33% "$f"
done
Palette
It seems you actually only want to output palettised (indexed) images with "any" colormap rather than with a "specific" colormap. Glenn's answer is perfect if you want to retain a specific colormap. However, if any colormap is ok, you can use -colors to reduce the colours in the resulting image to a level where the PNG library can make the decision to create a palettised image. Glenn knows a lot more than me about that as he wrote it! However, I think if you reduce the colours to 250 (or so) you will probably get a 256 entry colormap and if you reduce the colours to around 60 or so, you will get a 64 entry colourmap. So, you would do:
shopt -s nullglob
for f in *.png; do
sudo cp ... ...
convert "$f" \
\( +clone -resize 66.67% -colors 250 -write "${f/%.png/-2x.png}" +delete \) \
-resize 33.33% -colors 250 "$f"
done
You can try experimenting with other numbers of colours and see how that affects filesize - the number you need will depend on your images.
I have a strange probleam with running ImageMagick mogrify on several files. I use conversion string to make several transformation on images, which results in thumbnails. The command with the conversion string runs fine on single file, however when ran on a batch of files, it sometimes fails. Here is the command (windows command line):
"C:\Program Files\ImageMagick-6.3.5-Q16\mogrify" \
-format jpg \
-thumbnail 400x400">" \
-background white \
-gravity center \
-extent 400x400 \
-draw "image src-over 0,0 0,0 '//dell1/Oracle/files/watermark.png'" \
-path \\dell1\Oracle\files\pictures\cj4uoveomiggda97kmqttn0400 \
\\dell1\Oracle\files\pictures\59\59p5huflk2cnv9drf3r1d65ef9_wc \
\\dell1\Oracle\files\pictures\7v\7vi3q26cdidk8bproslhhmlkab_wc \
\\dell1\Oracle\files\pictures\ft\ft0iqkjk08cli8k0iltgmdmfo5_wc
and it fails with message "mogrify: Non-conforming drawing primitive definition `image'."
But I've found out, that this happens only when inserting a wattermark. I've also found out that when I change order of the 3 files which are to be processed, the mogrify runs fine, which is pretty strange. I have no idea why this happens and how to get rid of it.
PS: I execute this command from a java application, so using a batch file with repeated calling of convert command is not acceptable solution for me.
Any clues appreciated, many thanks.
Solved this by installing newer version of ImageMagick :/
How to convert a JPEG image into SVG format using ImageMagick?
you'll need to use potrace and convert to a bitmap first.
$convert input.jpg output.ppm
$potrace -s output.ppm -o svgout.svg
Actually, with a complete installation of a recent version of ImageMagick it should be as easy as:
convert some.jpeg some.svg
Of course, ImageMagick cannot do it all by itself -- it uses delegates (helper programs) to handle SVG input or output. (This has been pointed out by other answers already.)
To see a (partial) list of all delegates (and their respective commands), run
convert -list delegate
To see the config file where all the delegate secrets hide, see
convert -list delegate | grep delegates.xml
To see a (partial) list of SVG handling delegates, run
convert -list delegate | grep -i svg
However, ImageMagick likes to put some of its external helper utilities into 'stealth' mode and doesn't necessarily reveal their presence when using above commands.
Just look into the delegates.xml file itself. On my system it's:
grep -i svg /opt/local/etc/ImageMagick/delegates.xml | grep -i --color stealth
<delegate decode="autotrace" stealth="True" \
command=""/opt/local/bin/convert" "%i" \
"pnm:%u"\n\
"/opt/local/bin/autotrace" \
-input-format pnm \
-output-format svg \
-output-file "%o" "%u""/>
<delegate decode="svg:decode" stealth="True" \
command=""/opt/local/bin/inkscape" "%s" \
--export-png="%s" \
--export-dpi="%s" \
--export-background="%s" \
--export-background-opacity="%s" \
> "%s" 2>&1"/>
As you may see, on my system the ImageMagick installation automatically uses (amongst others)...
...inkscape to convert SVG to PNG;
...autotrace to convert PNM to SVG;
Of course, one could argue the benefits of rather using autotrace directly -- but that would require to manually convert the whatever-input-format to PNM first. So for this preliminary step you'd probably use ImageMagick anyway...
You'll actually need some software or code to vectorize your image in between, as jpg is a raster format, while SVG is a vector format. I don't think imagemagick alone can do that for you.