Recherche avancée

Sur d’autres sites (7647)

• Bash script for splitting video using ffmpeg outputs wrong video lengths

  19 juin 2018, par jonny

  I have a video that’s x seconds long. I want to split that video up into equal segments, where each segment is no longer than a minute. To do that, I cobbled together a fairly simple bash script which uses ffmprobe to get the duration of the video, find out how long each segment should be, and then iteratively split the video up using ffmpeg :

  INPUT_FILE=$1
  
  INPUT_DURATION="$(./bin/ffprobe.exe -i "$INPUT_FILE" -show_entries format=duration -v quiet -of csv="p=0")"
  
  
  
  NUM_SPLITS="$(perl -w -e "use POSIX; print ceil($INPUT_DURATION/60), qq{\n}")"
  
  
  
  printf "\nVideo duration: $INPUT_DURATION; "
  
  printf "Number of videos to output: $NUM_SPLITS; "
  
  printf "Approximate length of each video: $(echo "$INPUT_DURATION" "$NUM_SPLITS" | awk '{print ($1 / $2)}')\n\n"
  
  
  
  for i in `seq 1 "$NUM_SPLITS"`; do
  
      START="$(echo "$INPUT_DURATION" "$NUM_SPLITS" "$i" | awk '{print (($1 / $2) * ($3 - 1))}')"
  
      END="$(echo "$INPUT_DURATION" "$NUM_SPLITS" "$i" | awk '{print (($1 / $2) * $3)}')"
  
  
  
      echo ./bin/ffmpeg.exe -v quiet -y -i "$INPUT_FILE" \
  
      -vcodec copy -acodec copy -ss "$START" -t "$END" -sn test_${i}.mp4
  
  
  
      ./bin/ffmpeg.exe -v quiet -y -i "$INPUT_FILE" \
  
      -vcodec copy -acodec copy -ss "$START" -t "$END" -sn test_${i}.mp4
  
  done
  
  
  
  printf "\ndone\n"

  If I run that script on the 30MB / 02:50 duration Big Buck Bunny sample from here, the output of the program would suggest the videos should all be of equal length :

  λ bash split.bash .\media\SampleVideo_1280x720_30mb.mp4
  
  
  
  Video duration: 170.859000; Number of videos to output: 3; Approximate length of each video: 56.953
  
  
  
  ./bin/ffmpeg.exe -v quiet -y -i .\media\SampleVideo_1280x720_30mb.mp4 -vcodec copy -acodec copy -ss 0 -t 56.953 -sn test_1.mp4
  
  ./bin/ffmpeg.exe -v quiet -y -i .\media\SampleVideo_1280x720_30mb.mp4 -vcodec copy -acodec copy -ss 56.953 -t 113.906 -sn test_2.mp4
  
  ./bin/ffmpeg.exe -v quiet -y -i .\media\SampleVideo_1280x720_30mb.mp4 -vcodec copy -acodec copy -ss 113.906 -t 170.859 -sn test_3.mp4
  
  
  
  done

  As the duration of each partial video, i.e. the time between -ss and -t, are equal for each subsequent ffmpeg command. But the durations I get are closer to :

  test_1.mp4 = 00:56
  
  test_2.mp4 = 01:53
  
  test_3.mp4 = 00:56

  Where the contents of each partial video overlap. What am I missing here ?

• Start and end time of MoviePy's VideoClip not working

  21 mars 2024, par ernesto casco velazquez

  I'm trying to add captions to a video. The desired outcome is to show each word in the exact moment is being said.

  


  I have a method that gives me the accurate time start and end per each word :

  


  def get_words_per_time(audio_speech_file):
    model = whisper.load_model("base")
    transcribe = model.transcribe(
        audio=audio_speech_file, fp16=False, word_timestamps=True
    )
    segments = transcribe["segments"]
    words = []

    for seg in segments:
        for word in seg["words"]:
            words.append(
                {
                    "word": word["word"],
                    "start": word["start"],
                    "end": word["end"],
                    "prob": round(word["probability"], 4),
                }
            )
    return words


  


  Then I have a code that uses MoviePy to create TextClip and assing a given start and end time per pair of words (I know there are redundant statements, srry) :

  


  def generate_captions(
    words,
    font="Komika",
    fontsize=32,
    color="White",
    align="center",
    stroke_width=3,
    stroke_color="black",
):
    text_comp = []
    for i in track(range(0, len(words), 2), description="Creating captions..."):
        word1 = words[i]
        if i + 1 < len(words):
            word2 = words[i + 1]
        text_clip = TextClip(
            f"{word1['word']} {word2['word'] if i + 1 < len(words) else ''}",
            font=font,  # Change Font if not found
            fontsize=fontsize,
            color=color,
            align=align,
            method="caption",
            size=(660, None),
            stroke_width=stroke_width,
            stroke_color=stroke_color,
        )
        text_clip = text_clip.set_start(word1["start"])
        text_clip = text_clip.set_end(
            word2["end"] if i + 1 < len(words) else word1["end"]
        )
        text_comp.append(text_clip)
    return text_comp


  


  Finally, I concatenate the words into a single video :

  


  vid_clip = CompositeVideoClip(
    [vid_clip, concatenate_videoclips(text_comp).set_position(("center", 860))]
)


  


  The output is this, but you can clearly see the words are not flowing with the speech. They somehow move faster as if the start/end time did not matter. Here's the video

  


  The words with their respective start/end time, look like this :

  


  [
    {
        'word': 'This',
        'start': 0.0,
        'end': 0.22,
        'prob': 0.805
    },
    {
        'word': 'is',
        'start': 0.22,
        'end': 0.42,
        'prob': 0.9991
    },
    {
        'word': 'a',
        'start': 0.42,
        'end': 0.6,
        'prob': 0.999
    },
    {
        'word': 'test,
        ',
        'start': 0.6,
        'end': 1.04,
        'prob': 0.9939
    },
    {
        'word': 'to',
        'start': 1.18,
        'end': 1.3,
        'prob': 0.9847
    },
    {
        'word': 'show',
        'start': 1.3,
        'end': 1.54,
        'prob': 0.9971
    },
    {
        'word': 'words',
        'start': 1.54,
        'end': 1.9,
        'prob': 0.995
    },
    {
        'word': 'does',
        'start': 1.9,
        'end': 2.16,
        'prob': 0.997
    },
    {
        'word': 'not',
        'start': 2.16,
        'end': 2.4,
        'prob': 0.9978
    },
    {
        'word': 'appear.',
        'start': 2.4,
        'end': 2.82,
        'prob': 0.9984
    },
    {
        'word': 'At',
        'start': 3.46,
        'end': 3.6,
        'prob': 0.9793
    },
    {
        'word': 'their',
        'start': 3.6,
        'end': 3.8,
        'prob': 0.9984
    },
    {
        'word': 'proper',
        'start': 3.8,
        'end': 4.22,
        'prob': 0.9976
    },
    {
        'word': 'time.',
        'start': 4.22,
        'end': 4.72,
        'prob': 0.999
    },
    {
        'word': 'Thanks',
        'start': 5.04,
        'end': 5.4,
        'prob': 0.9662
    },
    {
        'word': 'for,
        ',
        'start': 5.4,
        'end': 5.66,
        'prob': 0.9941
    },
    {
        'word': 'watching.',
        'start': 5.94,
        'end': 6.36,
        'prob': 0.7701
    }
]


  


  What could be causing this ?

  


• How to convert an IP Camera video stream into a video file ?

  14 novembre 2014, par AgentFire

  I have a URL (<ip>/ipcam/mpeg4.cgi</ip>) which points to my IP camera which is connected via Ethernet.
  Accessing the URL resuls in a infinite stream of video (possibly with audio) data.

  I would like to store this data into a video file and play it later with a video player (HTML5’s video tag is preferred as the player).

  However, a straightforward approach, which is simple saving the stream data into .mp4 file, didn’t work.

  I have looked into the file and here is what I saw (click to enlarge) :

  

  It turned out, there are some HTML headers, which I further on manually excluded using the binary editing tool, and yet no player could play the rest of the file.

  The HTML headers are :

  --myboundary
  
  Content-Type: image/mpeg4
  
  Content-Length: 76241
  
  X-Status: 0
  
  X-Tag: 1693923
  
  X-Flags: 0
  
  X-Alarm: 0
  
  X-Frametype: I
  
  X-Framerate: 30
  
  X-Resolution: 1920*1080
  
  X-Audio: 1
  
  X-Time: 2000-02-03 02:46:31
  
  alarm: 0000

  My question is pretty clear now, and I would like any help or suggestion. I suspect, I have to manually create some MP4 headers myself based on those values above, however, I fail to understand format descriptions such as these.

  I have the following video stream settings on my IP camera (click to enlarge) :

  

  I could also use the ffmpeg tool, but no matter how I try and mix the arguments to the program, it keeps telling me this error :