I'm experimenting with pysox and trying to simply convert a WAV file to GSM.
I'm currently using the following approach which works just fine:
infile = pysox.CSoxStream("input_file.wav")
outfile = pysox.CSoxStream('output_file.gsm','w',infile.get_signal())
chain = pysox.CEffectsChain(infile, outfile)
chain.flow_effects()
outfile.close()
I wonder if there's a better/builtin way without using effects (as i'm not applying any effects) .
thanks in advance
I found that i actually must use libsox effect as i'm changing the rate :
chain.add_effect(pysox.CEffect("rate", ["8k"]))
Without adding this line the output appears in slow motion (since my original file can have different rate)
Related
In an old version of my code, I used to do a hardcopy() with a given resolution, ie:
frame = hardcopy(figHandle, ['-d' renderer], ['-r' num2str(round(pixelsperinch))]);
For reference, hardcopy saves a figure window to file.
Then I would typically perform:
ZZ = rgb2gray(frame) < 255/2;
se = strel('disk',diskSize);
ZZ2 = imdilate(ZZ,se); %perform dilation.
Surface = bwarea(ZZ2); %get estimated surface (in pixels)
This worked until I switched to Matlab 2017, in which the hardcopy() function is deprecated and we are left with the print() function instead.
I am unable to extract the data from figure handler at a specific resolution using print. I've tried many things, including:
frame = print(figHandle, '-opengl', strcat('-r',num2str(round(pixelsperinch))));
But it doesn't work. How can I overcome this?
EDIT
I don't want to 'save' nor create a figure file, my aim is to extract the data from the figure in order to mesure a surface after a dilation process. I just want to keep this information and since 'im processing a LOT of different trajectories (total is approx. 1e7 trajectories), i don't want to save each file to disk (this is costly, time execution speaking). I'm running this code on a remote server (without a graphic card).
The issue I'm struggling with is: "One or more output arguments not assigned during call to "varargout"."
getframe() does not allow for setting a specific resolution (it uses current resolution instead as far as I know)
EDIT2
Ok, figured out how to do, you need to pass the '-RGBImage' argument like this:
frame = print(figHandle, ['-' renderer], ['-r' num2str(round(pixelsperinch))], '-RGBImage');
it also accept custom resolution and renderer as specified in the documentation.
I think you must specify formattype too (-dtiff in my case). I've tried this in Matlab 2016b with no problem:
print(figHandle,'-dtiff', '-opengl', '-r600', 'nameofmyfig');
EDIT:
If you need the CData just find the handle of the corresponding axes and get its CData
f = findobj('Tag','mytag')
Then depending on your matlab version use:
mycdata = get(f,'CData');
or directly
mycdta = f.CData;
EDIT 2:
You can set the tag of your image programatically and then do what I said previously:
a = imshow('peppers.png');
set(a,'Tag','mytag');
Is it possible to load an Image from a remote URL using Images.jl, the same way you would load from a local file?
For reference:
using Images
yuss = load("mylocalimage.jpg") # Hooray
fail = load("https://www.wikipedia.org/portal/wikipedia.org/assets/img/Wikipedia-logo-v2#2x.png") # Sad
Trying to use the yuss success in the question to fix the fail problem:
using Images
img = mktemp() do fn,f
download("https://www.wikipedia.org/portal/wikipedia.org/assets/img/Wikipedia-logo-v2#2x.png", fn)
load(fn)
end
Or instead of using an external download tool, the HTTP package can be used (also this avoids the do syntax which might confuse):
using Images
using HTTP
t = tempname()
HTTP.download("https://www.wikipedia.org/portal/wikipedia.org/assets/img/Wikipedia-logo-v2#2x.png", t)
img = load(t)
rm(t)
Admittedly, using a temporary file is not the prettiest code. Is this enough for Hooray?
ADDITION
See other answer for an even shorter version thanks to Simon Danish.
#Simon Danisch sent me a pretty good solution offline:
julia> using FileIO
julia> download("https://www.wikipedia.org/portal/wikipedia.org/assets/img/Wikipedia-logo-v2#2x.png") |> load
Apparently download() defaults to creating a temporary file, and returns the full-name of it as a string. Basically the same as #Dan Getz's answer, but a bit simpler.
It's too bad we have to interact with the file system at all, but I suppose this will do for now.
Using HTTP.jl to stream the image without saving a temporary file on disk:
using HTTP, Images
url = "https://user-images.githubusercontent.com/6933510/107239146-dcc3fd00-6a28-11eb-8c7b-41aaf6618935.png"
philip = HTTP.get(url).body |> IOBuffer |> load
The background of my problem is that I want to extract the video data of Motion Photos (taken by my Samsung S7). Manually it is easy but time consuming. Just open the .jpg file in a HexEditor and extract all data after the line "MotionPhoto_Data". The first part is the image and the second part is the video.
My current code is
im = 'test.jpg'
with open(im, 'rb') as fin:
data = fin.read()
data_latin = data.decode('latin1')
fin.close()
position = data_latin.find('MotionPhoto_Data')
data_pic = data[:position]
data_mpg = data[position:]
My problem now is that I can´t figure out how to save these strings in a way that data_pic is saved as a working jpg and data_mpg as a working video.
I tried
with open('test_pic.jpg', 'a') as fin:
fin.write(str(data_pic))
fin.close()
But this didn´t worked. I think there is a basic issue on how I try to handle/save my data but I can´t figure out how to fix this.
I assume you use python 3 as it is tagged that way.
You should not decode with 'data.decode('latin1'). It is binary data.
data = fin.read()
Then later write it also as binary data:
with open('test_pic.jpg', 'ab') as fout:
fout.write(data_pic)
fout.close()
I was hoping to be able to generate montages using PythonMagick. The documentation seems very sparse, but I've been trying to hunt it down using the code completion part of Eclipse at least, as well as a few other questions' suggestions here on Stack Overflow. It seems that the MagickWand API has the function I am looking for, according to this:
http://www.imagemagick.org/api/MagickWand/montage_8c.html
However, I cannot seem to find it in PythonMagick. Is this simply unavailable? If so I might just ditch the rest of my PythonMagick code and rely on subprocess.call on a portable ImageMagick distribution or something like that (this program will have to be portable, and run on Windows with an easy port to Mac OS... so far I have a few other PythonMagick commands working so I'd like to keep this route going if possible).
Thanks!
Using the python imagemagick/graphicsmagick bindings helps a lot, but unfortunately not all of the functionality is there yet. I actually had the same problem with #FizxMike. I needed to use montage and then do some further operations, but saving the file on hard disk and then reloading it in a proper pgmagick object in order to do the rest of the operations and saving it again was slow.
Eventually I used the subprocess solution, but instead of saving in a file, I redirect the output in stdout. Then, I use the stdout to load the image from a pgmagick.Blob in a pgmagick.Image object and do the rest of the processing in python code.
The procedure looks like this in code:
import os
import pgmagick
import subprocess
my_files = []
# Dir with the images that you want to operate on
dir_with_images = "."
for file in os.listdir(dir_with_images):
if file.endswith(".png"):
my_files.append(os.path.join(dir_with_images, file))
montage_cmd = ['gm', 'montage']
montage_cmd.extend(my_files)
# The trick is in the next line of code. Instead of saving in a file, e.g. myimage.png
# the montaged file will just be "printed" in the stdout with 'png:-'
montage_cmd.extend(['-tile', '2x2', '-background', 'none', '-geometry', '+0+0', 'png:-'])
# Use the command line 'gm montage' since there are not python bindings for it :(
p = subprocess.Popen(montage_cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
# Get the stdout in a variable
stdout, stderr = p.communicate()
# Load the stdout in a python pgmagick Image object using the pgmagick.Blob
# and do the rest of the editing on python code
img = pgmagick.Image(pgmagick.Blob(stdout))
# Display the image
img.display()
geometry = pgmagick.Geometry(300, 200)
geometry.aspect(True)
# Resize the montaged image to 300x200, but keep the aspect ratio
img.scale(geometry)
# Display it again
img.display()
# And finally save it <- Only once disk access at this point.
img.write('myimage.png')
I have the same problem, even pgmagick lacks the montageImage() function needed (Magick++ montage example)
This is what I do (in a Django View):
#ImageMagick CLI is better documented anyway (-background none preserves transparency)
subprocess.call("montage -border 0 -geometry "+str(cols)+"x -tile 1x"+str(len(pages))+" "+target_path[0:len(target_path)-4]+"[0-9]*.png -background none "+target_path,shell=True)`
Not fun because I have to juggle around a bunch of files first... writing to hard disk is not the fastest thing to do, then delete the temp files.
I would much rather do it all in ram.
I am still in search of a better answer myself.
I am developing an application in Java. Part of it includes playing an mp3 file via another application. I need to find the duration (total play time) of the mp3 file. How do I do that?
You can do this very easily using JAudioTagger:
Tag tag;
java.util.logging.Logger.getLogger("org.jaudiotagger").setLevel(Level.OFF);
audioFile = AudioFileIO.read(new File(filePath));
System.out.println("Track length = " + audioFile.getAudioHeader().getTrackLength());
That will print out the track length of the file at filePath. The logger line is to remove a lot of (probably) unwanted info/debugging logging from JAudioTagger. Besides this, JAudioTagger supports getting all sorts of metadata tags from different audio file types (MP3, MP4, WMA, FLAC, Ogg Vorbis), both from file-embedded tags. You can even get MusicBrainz info easily, but I haven't tried that yet. For more info:
http://www.jthink.net/jaudiotagger/examples_read.jsp
You can get the jar files for it here:
http://download.java.net/maven/2/org/jaudiotagger/
For small .mp3 files you can use:
AudioFile audioFile = AudioFileIO.read(MyFileChooser.fileName);
int duration= audioFile.getAudioHeader().getTrackLength();
System.out.println(duration);
This will give a string containing the minute and second duration in it. eg: 316 for 3:16.
Note that This method is not suitable with larger files.