First, I'm not a developer. I'm trying to split a movie into 1 minute clips usinf ffmpeg-split.py python script. I made sure FFmpeg is installed it trying a simple command and it worked like magic:
ffmpeg -i soccer.mp4 -ss 00:00:00 -codec copy -t 10 soccer1.mp4
A new video file was created in the same folder.
I saved the FFmpeg-split.py in the same dir, updated python PATH and typed the following command:
python ffmpeg-split.py -f soccer.mp4 -s 10
what I got back was:
can't determine video length
I believe it just can't find the file. I switched video files and even deleted it and got the same message.
Any ideas?
first time I've seen that name!? Because I believe you were able to run ffmpeg from the command line and execute basic python stuff I recommend following my example as it should avoid any weird directory.connection.stuff in the given file (which i ignored). "Earlier that day": Let me ignore the .py script and share as follows:
Assuming you ran
ffmpeg -i soccer.mp4 ...stuff... soccer1.mp4
from a windows.command.line...
It would be better to write
ffmpeg -t 10 -i "Z:\\full\\input\\path.mp4" -c copy "Z:\\full\\output\\path.mp4"
This says, run ffmpeg, -t=input.duration.seconds, -i=input.file.next,
"fullinpath" in quotes cause spaces etc., -c=all.codecs, copy=atlantian.magic.trick,
"fulloutpath" also to be safe, nothing else!
"Piping" through python to windows works great for this:
import subprocess as subprocess
def pegRunner(cmd): #Takes a list of strings we'll pass to windows.
command = [x for x in cmd] # peg short for mpeg, shoulda used meg.gem.gepm.gipper.translyvania.otheroptions
result = subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
output, err = result.communicate()
print result.wait()
return "pegRannered"
#########
# Find the duration from properties or something. If you need to do this
# often it's more complicated. Let's say you found 4mins33secs.
############
leng = 4*60+33 # time in seconds
last_dur = int(leng%60) #remaining time after the 4 one.min.vids
if last_dur == 0: num_vids = int(leng/60)
else: num_vids = int(leng/60)+1
for i in range(num_vids):
da_command = ['ffmpeg']
da_command.append('-ss')
da_command.append(str(i*60))
da_command.append('-t')
if i != num_vids: da_command.append('60')
else: da_command.append(str(last_dur))
da_command.append('-i')
da_command.append('Z:\\full\\input\\path.mp4') #this format!
da_command.append('-c')
da_command.append('copy')
#optionally to overwrite!!!! da_command.append('-y')
da_command.append('Z:\\full\\output\\path\\filename_'+str(i)+'.mp4')
print pegRunner(da_command)
print "Finished "+str(i)+" filez."
This should handle the 1.min pieces and provide a good starting place for ffmpeg from python.
Related
I am trying to extract the frames when the scene changes in an .mp4 video.
The package that I am using is FFMPEG.
FFMPEG predominantly works on the CLI and I am trying to integrate it with Python3.x
The command I am using in the CLI is:
ffmpeg -i {0} -vf "select=gt(scene\,0.5), scale=640:360" -vsync vfr frame%d.png
The output comes out just fine with the CLI execution.
But I want to use same command in a Python script, how do I do that and what should be the code?
Being an amateur in the field, currently grappling with this!
You could execute that command from Python via subprocess module, of course, but it would better to use library like https://github.com/kkroening/ffmpeg-python
I would recommend PyAV. it's a proper wrapper around ffmpeg's libraries.
the other mentioned packages use the "subprocess" approach, which is limited and inefficient. these libraries may be more convenient than plain ffmpeg APIs.
Thanks for the help!
This is the snippet of code I'm currently using and it gives the results as I require.
I have added a functionality for timestamp generation of the frames in addition to the frame formation using scene change detection
===========================================================================
> # FFMPEG Package call through script
> # need to change the location in the cmd post -vsync vfr to the location where the frames are to be stored
> # the location should be same as where the videos are located
============================================================================
inputf = []
for filename in os.listdir(path):
file= filename.split('.')[0] # Splits the file at the extension and stores it without .mp4 extension
input_file = path + filename
inputf.append(input_file) # Creates a list of all the files read
for x in range (0, len(inputf)):
cmd = f'ffmpeg -i {inputf[x]} -filter_complex "select=gt(scene\,0.2), scale=640:360, metadata=print:file=time_{file}.txt" -vsync vfr {path where the videos are located}\\{file}_frame%d.jpg'
os.system(cmd)
x=x+1
print("Done") # Takes time will loop over all the videos
I want to run from Python script next command:
strings <FILE NAME> | grep "Version = <VERSION STRING>" > /dev/null
I need to save command return code and command output for following script logic.
Currently I used next code:
strings_out = subprocess.Popen(('strings', file), stdout=subprocess.PIPE)
grep_output = subprocess.check_output(('grep', "Version = " + version_string), stdin=strings_out.stdout)
strings_out.wait()
I get error
subprocess.CalledProcessError: Command '('grep', 'Version = <VERSION STRING>')' returned non-zero exit status 1
My assumption is that check_output run out of memory.
What is wrong in my use of subprocess?
A non-zero exit status for a check_output means that the bash command had a problem - I don't think you ran out of memory.
On testing myself, I found that if I gave grep a string that exists within a file, I got a proper output with your code (I'm not using Version because I don't know what input files you have, but otherwise things are just about the same). I do, however, get the same error you get if I grep a string that doesn't exist.
Maybe you are running it on a file that string doesn't output any instances of "Version = " + version_string. If you are in a loop, it would only take one file to not have the proper string to get the error.
On another note, if you plan on finishing this line: strings <FILE NAME> | grep "Version = <VERSION STRING>" > /dev/null with subprocess, you'll be piping the output to /dev/null. In this case, you won't see the output of grep.
As #samsonjm has mentioned, every successfully ran bash command has the exit code = 0. It implies that the grep command has failed. Moreover, there is no clue for an OutofMemory error.
I suspect that input file to the strings command is large and hence it could be taking more time to return its result. Therefore, I suspect the string_out.wait() directive should be called immediately after the first line above to feed in the input from stdin to the grep command. It is reasonable to think in this way as the subprocess executes commands in a child process that might be running until completion.
strings_out = subprocess.Popen(('strings', file), stdout=subprocess.PIPE)
strings_out.wait()
grep_output = subprocess.check_output(('grep', "Version = " + version_string), stdin=strings_out.stdout)
That's neat, I've never thought to use subprocess stdin/stdout like that before. However, my advice would be to either go pure Python and write a method to search for the string in a file, or get a little fancier with your subprocess line.
Python might look something like:
import os
search_term = bytes("Version = " + version_string, encoding='utf-8')
i = 0
found = False
file_size = os.stat(f).st_size
chunk_size = len(search_term) *10
with open(file_name, 'rb') as f:
while f.tell() < size:
x = f.read() #read a small amount of data
i += chunk_size - len(search_term) #to make sure we don't miss the search_term
f.seek(i)
if search_term in x:
found = True
break
For subprocess:
cmd = f'strings {file_name} | grep "Version = {version_string}"'
test = subprocess.run([cmd], shell=True, capture_output=True)
test.returncode
I am using Inkscape to take an input single page pdf file and to output an svg file. The following works from the command line
c:\progra~1\Inkscape\inkscape -z -f "N:\pdf_skunkworks\inflation-report-may-2018-page0.pdf" -l "N:\pdf_skunkworks\inflation-report-may-2018-page0.svg"
where -z is short for --without-gui, -f is short for input file, -l is short for --export-plain-svg. And that works from command line.
I could not get the equivalent to work from Python, either passing the command line as one long string or as separate arguments. stderr and stdout give no error as they both print None
import subprocess #import call,subprocess
#completed = subprocess.run(["c:\Progra~1\Inkscape\Inkscape.exe",r"-z -f \"N:\pdf_skunkworks\inflation-report-may-2018-page0.pdf\" -l \"N:\pdf_skunkworks\inflation-report-may-2018-page0.svg\""])
completed = subprocess.run(["c:\Progra~1\Inkscape\Inkscape.exe","-z", r"-f \"N:\pdf_skunkworks\inflation-report-may-2018-page0.pdf\"" , r"-l \"N:\pdf_skunkworks\inflation-report-may-2018-page0.svg\""])
print ("stderr:" + str(completed.stderr))
print ("stdout:" + str(completed.stdout))
Just to test OS plumbing I wrote some VBA code (my normal language) and this works
Sub TestShellToInkscape()
'* Tools->References->Windows Script Host Object Model (IWshRuntimeLibrary)
Dim sCmd As String
sCmd = "c:\progra~1\Inkscape\inkscape -z -f ""N:\pdf_skunkworks\inflation-report-may-2018-page0.pdf"" -l ""N:\pdf_skunkworks\inflation-report-may-2018-page0.svg"""
Debug.Print sCmd
Dim oWshShell As IWshRuntimeLibrary.WshShell
Set oWshShell = New IWshRuntimeLibrary.WshShell
Dim lProc As Long
lProc = oWshShell.Run(sCmd, 0, True)
End Sub
So I'm obviously doing something silly in the Python code. I'm sure experienced Python programmer could solve easily.
Swap your slashes:
import subprocess #import call,subprocess
completed = subprocess.run(['c:/Progra~1/Inkscape/Inkscape.exe',
'-z',
'-f', r'N:/pdf_skunkworks/inflation-report-may-2018-page0.pdf' ,
'-l', r'N:/pdf_skunkworks/inflation-report-may-2018-page0.svg'])
print ("stderr:" + str(completed.stderr))
print ("stdout:" + str(completed.stdout))
Python knows to swap forward slashes for back slashes on windows OS, and your back slashes are currently acting as escape prefixes.
I'm working on a script to call an executable for i/o files. I'm using subprocess and trying to shell out the exe and the stdout to a log file. Problem is I would like to output a simple ascii file and I'm getting a hexadecimal file. Just really learning to program python (or any language for that matter) so, I'm assuming there some type of formatting I can do but I just don't get it. I've done a fair bit of searching on this site and others but I haven't anything like what I'm using subprocess for. The "outRadcorr" is what I need help on the most...Any ideas? More code on request.
Import system modules
import os, sys, string, traceback, time, datetime
import params
from subprocess import Popen, PIPE, STDOUT
...some code here.....
Write stdout to log file
rad_log_file = open(dsFolder + '\\radcorr.log', 'w')
# loop through the files in raw file list to run radiometric correction
for rawfiles in rawFolderList:
# Define the file base
rawBase = rawfiles.split(".")[0]
print ('\nProcessing file: %s \n')%( rawBase )
# define variables from raw file to process radcorr
radFile = rawfiles
pixFile = ('%s.pix')%( rawBase )
attFile = ('%s.att')%( rawBase )
# create windose bat file function
def rad_bat_writer( radcorr_bat ):
with open(dsFolder + '\\radcorr.bat', 'a') as rad_bat_file:
rad_bat_file.write(radcorr_bat + '\n')
# grab radcor input/output files and run radcorr.exe
radcorr = ('C:\\itres\\bin\\radcorr.exe -f 1 -j 100 -g 50 -s -1 -n -1 %s %s %s -i '+ rawFolder + '\%s,rb -o ' + radFolder + '\%s -a ' \
+ radFolder + '\%s -c C:\\itres\\rad_cal_files\\%s -I 0 -v 0 -r Y -R Y -^^ 2') %( sum,scatter,shift,radFile,pixFile,attFile,rad_prefix )
# print out radcorr command
print radcorr
# Execute radcorr and write stdout
outRadcorr = Popen("{};".format(radcorr), stdout=PIPE, stderr=STDOUT)
for line in outRadcorr.stdout:
sys.stdout.write(line)
rad_log_file.write(line)
# write output to log
rad_bat_writer( radcorr )
# Close out exe and log files
outRadcorr.wait()
rad_log_file.close()
I was using UltraEdit to view the file, which you can view hex files in. I was not looking in hex mode. I might be confusing the terminology here. File looks normal in NotePad/NotePad++/WordPad etc. As I ran the script in debug mode, I could hit the loop file by file. First two files (1GB/file), the output log looked fine. Once the radcorr.log file was over 10kb, I change from a normal ascii output to this binary file viewed that looked hex. I can't post images yet, but just google ultraedit hexadecimal.
Still not sure why it moved to this format. Finally, output size was 45kb. I change to view/edit hex mode in UltraEdit and it looks fine. Just wanted to get it out there to see if others had any ideas why when I specified the log to be 'w' and not 'wb', for instance.
I do appreciate all you help. #J.F. Sebastian I'll have to test the code you posted, probably help fix potential bugs down the road.
youtube-dl is a Python script that allows one to download YouTube videos. It supports an option for batch downloads:
-a FILE, --batch-file=FILE
file containing URLs to download ('-' for stdin)
I want to setup some sort of queue so I can simply append URLs to a file and have youtube-dl process them. Currently, it does not remove files from the batch file. I see the option for '-' stdin and don't know if I can use this to my advantage.
In effect, I'd like to run youtube-dl as some form of daemon which will check the queue file and download the contained file names.
How can I do this?
The tail -f will not work because the script reads all the input at once.
It will work if you modify the script to perform a continuous read of the batch file.
Then simply run the script as:
% ./youtube-dl -a batch.txt -c
When you append some data into batch.txt, say:
% echo "http://www.youtube.com/watch?v=j9SgDoypXcI" >>batch.txt
The script will start downloading the appended video to the batch.
This is the patch you should apply to the latest version of "youtube-dl":
2278,2286d2277
< while True:
< batchurls = batchfd.readlines()
< if not batchurls:
< time.sleep(1)
< continue
< batchurls = [x.strip() for x in batchurls]
< batchurls = [x for x in batchurls if len(x) > 0]
< for bb in batchurls:
< retcode = fd.download([bb])
Hope it helps,
Happy video watching
;)
NOTE: Due to code restructuring this patch will no longer work. Would be interested to see if this could be added to the upstream code.
You might be able to get away with using tail -f to read from your file. It will not exit when it reaches end-of-file but will wait for more data to be appended to the file.
>video.queue # erase and/or create queue file
tail -f video.queue | youtube-dl -a -
Since tail -f does not exit, youtube-dl should continue reading file names from stdin and never exit.