Recherche avancée

Sur d’autres sites (7703)

• ffmpeg takes a while to start

  17 octobre 2020, par Suspended

  I have this command in python script, in a loop :

  


  ffmpeg -i somefile.mp4 -ss 00:03:12 -t 00:00:35 piece.mp4 -loglevel error -stats


  


  It cuts out pieces of input file (-i). Input filename, as well as start time (-ss) and length of the piece I cut out (-t) varies, so it reads number of mp4 files and cuts out number of pieces from each one. During execution of the script it might be called around 100 times. My problem is that each time before it starts, there is a delay of few seconds and it adds up to significant time. How can I get it to start immediately ?

  


  The script (process_videos.py) :
  

  


  import subprocess
import sys
import math
import time

class TF:
    """TimeFormatter class (TF).
This class' reason for being is to convert time in short
form, e.g. 1:33, 0:32, or 23 into long form accepted by
mp4cut function in bash, e.g. 00:01:22, 00:00:32, etc"""

def toLong(self, shrt):
    """Converts time to its long form"""
    sx = '00:00:00'
    ladd = 8 - len(shrt)
    n = sx[:ladd] + shrt
    return n

def toShort(self, lng):
    """Converts time to short form"""
    if lng[0] == '0' or lng[0] == ':':
        return self.toShort(lng[1:])
    else:
        return lng

def toSeconds(self, any_time):
    """Converts time to seconds"""
    if len(any_time) < 3:
        return int(any_time)
    tt = any_time.split(':')
    if len(any_time) < 6:            
        return int(tt[0])*60 + int(tt[1])
    return int(tt[0])*3600 + int(tt[1])*60 + int(tt[2])

def toTime(self, secsInt):
    """"""
    tStr = ''
    hrs, mins, secs = 0, 0, 0
    if secsInt >= 3600:
        hrs = math.floor(secsInt / 3600)
        secsInt = secsInt % 3600
    if secsInt >= 60:
        mins = math.floor(secsInt / 60)
        secsInt = secsInt % 60
    secs = secsInt
    return str(hrs).zfill(2) + ':' + str(mins).zfill(2) + ':' + str(secs).zfill(2)

def minus(self, t_start, t_end):
    """"""
    t_e = self.toSeconds(t_end)
    t_s = self.toSeconds(t_start)
    t_r = t_e - t_s
    hrs, mins, secs = 0, 0, 0
    if t_r >= 3600:
        hrs = math.floor(t_r / 3600)
        t_r = t_r - (hrs * 3600)
    if t_r >= 60:
        mins = math.floor(t_r / 60)
        t_r = t_r - (mins * 60)
    secs = t_r
    hrsf = str(hrs).zfill(2)
    minsf = str(mins).zfill(2)
    secsf = str(secs).zfill(2)
    t_fnl = hrsf + ':' + minsf + ':' + secsf
    return t_fnl

def go_main():
    tf = TF()
    vid_n = 0
    arglen = len(sys.argv)
    if arglen == 2:
        with open(sys.argv[1], 'r') as f_in:
            lines = f_in.readlines()
            start = None
            end = None
            cnt = 0
            for line in lines:
                if line[:5] == 'BEGIN':
                    start = cnt
                if line[:3] == 'END':
                    end = cnt
                cnt += 1
            if start == None or end == None:
                print('Invalid file format. start = {}, end = {}'.format(start,end))
                return
            else:
                lines_r = lines[start+1:end]
                del lines
                print('videos to process: {}'.format(len(lines_r)))
                f_out_prefix = ""
                for vid in lines_r:
                     vid_n += 1
                    print('\nProcessing video {}/{}'.format(vid_n, len(lines_r)))
                    f_out_prefix = 'v' + str(vid_n) + '-'
                    dat = vid.split('!')[1:3]
                    title = dat[0]
                    dat_t = dat[1].split(',')
                    v_pieces = len(dat_t)
                    piece_n = 0
                    video_pieces = []
                    cmd1 = "echo -n \"\" > tmpfile"
                    subprocess.run(cmd1, shell=True)                    
                    print('  new tmpfile created')
                    for v_times in dat_t:
                        piece_n += 1
                        f_out = f_out_prefix + str(piece_n) + '.mp4'
                        video_pieces.append(f_out)
                        print('  piece filename {} added to video_pieces list'.format(f_out))
                        v_times_spl = v_times.split('-')
                        v_times_start = v_times_spl[0]
                        v_times_end = v_times_spl[1]
                        t_st = tf.toLong(v_times_start)
                        t_dur = tf.toTime(tf.toSeconds(v_times_end) - tf.toSeconds(v_times_start))
                        cmd3 = ["ffmpeg", "-i", title, "-ss", t_st, "-t", t_dur, f_out, "-loglevel", "error", "-stats"]
                        print('  cutting out piece {}/{} - {}'.format(piece_n, len(dat_t), t_dur))
                        subprocess.run(cmd3)
                    for video_piece_name in video_pieces:
                        cmd4 = "echo \"file " + video_piece_name + "\" >> tmpfile"
                        subprocess.run(cmd4, shell=True)
                        print('  filename {} added to tmpfile'.format(video_piece_name))
                    vname = f_out_prefix[:-1] + ".mp4"
                    print('  name of joined file: {}'.format(vname))
                    cmd5 = "ffmpeg -f concat -safe 0 -i tmpfile -c copy joined.mp4 -loglevel error -stats"
                    to_be_joined = " ".join(video_pieces)
                    print('  joining...')
                    join_cmd = subprocess.Popen(cmd5, shell=True)
                    join_cmd.wait()
                    print('  joined!')
                    cmd6 = "mv joined.mp4 " + vname
                    rename_cmd = subprocess.Popen(cmd6, shell=True)
                    rename_cmd.wait()
                    print('  File joined.mp4 renamed to {}'.format(vname))
                    cmd7 = "rm " + to_be_joined
                    rm_cmd = subprocess.Popen(cmd7, shell=True)
                    rm_cmd.wait()
                    print('rm command completed - pieces removed')
                cmd8 = "rm tmpfile"
                subprocess.run(cmd8, shell=True)
                print('tmpfile removed')
                print('All done')
    else:
        print('Incorrect number of arguments')

############################
if __name__ == '__main__':
    go_main()


  


  process_videos.py is called from bash terminal like this :

  


  $ python process_videos.py video_data   


  


  video_data file has the following format :

  


  BEGIN
!first_video.mp4!3-23,55-1:34,2:01-3:15,3:34-3:44!
!second_video.mp4!2-7,12-44,1:03-1:33!
END


  


  My system details :

  


  System:    Host: snowflake Kernel: 5.4.0-52-generic x86_64 bits: 64 Desktop: Gnome 3.28.4
           Distro: Ubuntu 18.04.5 LTS
Machine:   Device: desktop System: Gigabyte product: N/A serial: N/A
Mobo:      Gigabyte model: Z77-D3H v: x.x serial: N/A BIOS: American Megatrends v: F14 date: 05/31/2012
CPU:       Quad core Intel Core i5-3570 (-MCP-) cache: 6144 KB 
           clock speeds: max: 3800 MHz 1: 1601 MHz 2: 1601 MHz 3: 1601 MHz 4: 1602 MHz
Drives:    HDD Total Size: 1060.2GB (55.2% used)
           ID-1: /dev/sda model: ST31000524AS size: 1000.2GB
           ID-2: /dev/sdb model: Corsair_Force_GT size: 60.0GB
Partition: ID-1: / size: 366G used: 282G (82%) fs: ext4 dev: /dev/sda1
           ID-2: swap-1 size: 0.70GB used: 0.00GB (0%) fs: swap dev: /dev/sda5
Info:      Processes: 313 Uptime: 16:37 Memory: 3421.4/15906.9MB Client: Shell (bash) inxi: 2.3.56


  


• Using a Web-based installer to retrieve (not distribute) 3rd party GPL or non-free software

  25 août 2013, par user1493918

  I am developing a software product which is able to communicate over a command line interface with GPL-covered software (specifically, my software can feed commands to FFMpeg). I understand that a crucial aspect of the GPL license is whether or not you distribute GPL-covered applications. My goal is to allow my users to have a seamless experience installing both my software and 3rd party GPL software. But I am trying to do this without my software actually including the the 3rd party (GPL-covered) software. To do this I am considering Web-based installers. I could use a Web-based installer to allow the end-user the option to retrieve a GPL-covered or non-free software app from a totally different server, independent of my own and outside my control. The user would be the one to install the software simply by making a decision (i.e. pressing "Next" in my installer). If they chose to do so, then my software's Web-based installer would retrieve the 3rd-party software, decompress and install it, then move on to installing my own application. In this way, my installer doesn't ship any GPL-covered or non-free software, and yet from the user's perspective all they had to do is click Next... Next... Next... Done !

  I have read about the GPL allowing you to distribute GPL-covered apps as part of an "aggregate..."
  http://www.gnu.org/licenses/gpl-faq.html#MereAggregation

  ...but this scenario isn't that. It's allowing the user to retrieve applications or libraries at his own discretion, using his own bandwidth, downloading from a server that has nothing to do with me.

  I can't seem to find information anywhere about the GPL-related licensing implications of using a Web-based installer. My goal is simply to give the end user every high-quality transcoding option possible within FFMpeg without stepping on anybody's toes legally.

  Possible ? If so then I'm hoping someone might be able to point me to a software installer program that would facilitate this. Thank you in advance for any replies.

• FFMPEG using wrong arguements when refering to image files

  14 août 2013, par Chad Marmon

  I am creating a bat file that will use FFMPEG to convert Real Media files to .MP4 files. I am looping though the current folder and finding files with the .rm extension adding several pictures to the video files to create a slide show effect in the final product.

  With this code here it works except it only shows one static image :

  for %%a in ("*.rm") do ffmpeg -f image2 -r 1/5 -i "img00.jpg" -i "%%a" -c:v libx264 -r 30 -preset slow -crf 20 -c:a libvo_aacenc -b:a 48k -b:v 16k "newfiles\%%~na.mp4"

  With this code it should show a series of photos. However it does not :

  for %%a in ("*.rm") do ffmpeg -f image2 -r 1/5 -i "img%02d.jpg" -i "%%a" -c:v libx264 -r 30 -preset slow -crf 20 -c:a libvo_aacenc -b:a 48k -b:v 16k "newfiles\%%~na.mp4"

  I get this error when I run the second piece of code :

  Could find no file with with path 'imgC :\Data\RealtoMP\FFMPEG_JPG\ffmpegA48V16_AudOnly' and index in the range 0-4
  imgC :\Data\RealtoMP\FFMPEG_JPG\ffmpegA48V16_AudOnly : No such file or directory

  It appears to me that it is somehow instead of getting the range argument like it should, it's injecting the path to the file that I am running. Any ideas of what is causing this ?

  EDIT :

  I fixed my problem by escaping the %02 with another %. The result is %%02 for it to act correctly in the script.