Recherche avancée

Sur d’autres sites (11790)

• How to add Title in video by ffmpeg on Node JS

  22 juin 2015, par Nazmul Hossain Bilash

  I am working on a project where I have to add Title on a video by FFmpeg. I have already succeeded in adding a picture on a video. Can anybody help me to add Text(Title) on a video ?

  Here is my code for adding Image, please suggest the required modification :

      try {
  
          var process = new ffmpeg('public/'+req.body.video);
  
          process.then(function (video) {
  
            console.log('The video is ready to be processed');
  
            var watermarkPath = 'public/images/logo.png',
  
              newFilepath = 'public/videos/watermarked/'+name,
  
              settings = {
  
                  position        : "SC"      // Position: NE NC NW SE SC SW C CE CW
  
                , margin_nord     : null      // Margin nord
  
                , margin_sud      : null      // Margin sud
  
                , margin_east     : null      // Margin east
  
                , margin_west     : null      // Margin west
  
              };
  
            var callback = function (error, files) {
  
              if(error){
  
                console.log('ERROR: ', error);
  
              }
  
              else{
  
                console.log('TERMINOU', files);
  
                res.send('videos/watermarked/'+name)
  
              }
  
            }
  
            //add watermark
  
            video.fnAddWatermark(watermarkPath, newFilepath, settings, callback)
  
  
  
          }, function (err) {
  
            console.log('Error: ' + err);
  
          });
  
        } catch (e) {
  
          console.log(e.code);
  
          console.log(e.msg);
  
        }

• FFmpeg muxing theora/vorbis unable to flush ?

  11 novembre 2013, par user2979732

  I'm pretty new to ffmpeg and it's confusing. I'm working on a basic muxer and have been spending over a week on this - I don't normally post as I solve 98% of my issues with google, but unable to get this one so far.

  The basis of my source is FFmpeg's own muxing.c example. When I try to force it using libvorbis for audio, and create "test.ogg" it demonstrates the same issues I'm having in my own derivation of muxing.c. The problem is with ogg/theora/vorbis. I'm forcing the use of audio codec like this :

  audio_st = add_stream(oc, &audio_codec, avcodec_find_encoder_by_name("libvorbis")->id);

  It seems the problem is in not setting audio pts in the muxing.c sample. There is a confusion in general about this, nobody apart from this guy didn't address what I am looking for http://webcache.googleusercontent.com/search?q=cache:6ml82RMN3YYJ:ffmpeg.org/pipermail/libav-user/2013-April/004304.html+&cd=4&hl=en&ct=clnk&gl=cz

  I couldn't find any answers to that naturally - like why don't they set the audio pts ? Laziness ? Not needed ? Do they believe all encoders will produce the pts for them(not true as seen below) ?

  Anyway, when you try muxing.c with mp4/libx264/forced libmp3lame all is fine, but the encoder says that "encoder did not produce valid pts, making some up.". However, it's silent with ogg/theora/vorbis, as if there were valid pts(?) but the result is no audio packets present in the stream(!), at least from what I saw using ffprobe. Which results in the video not being able to replay even, until you take out the empty audio stream. Then it plays the video, which shows that stream is fine.

  Coming to my original issue. I tried setting the pts on the audio frame you're sending to the encoder to fix that problem(this already sucks). I was unable to find a definite answer how to properly set the pts - that's the other big issue as I'm trying stuff which I'm not sure works. Anyway, in the end when setting "some" pts, this results in ogg with sound.

  if (frame->pts == AV_NOPTS_VALUE) frame->pts = audio_sync_opts;
  
  audio_sync_opts = frame->pts + frame->nb_samples;

  I'm aware I should probably use rescaling to adjust for the container time bases etc..if this was present/explained in ffmpeg's own sample I wouldn't have to guess now (as I'm stil not 100% sure about time base relationship between container and codec, I think container time base takes somehow over the codec one).

  My other problem is flushing - but that might have something to do with the screwed up pts. So I won't rather get into that in detail - the basic problem is, when I send finite number of audio frames, like 20, I get 2 packets only for example. From my understanding, I need to flush the rest of audio after all the encoding/muxing is done, which I managed to do with mp4/libx264/libmp3lame, but with ogg/theora/vorbis it doesn't flush. Why not, I have no idea.

  If someone could rework muxing.c into sending it finite number of audio / video frames - ie . not until duration > X, but until it sent 20 video & 100 audio frames(just an example). So that number of frames I have is important, not the video time I end up with. Then encode / mux all the frames - with proper video/audio pts, working with theora/ogg and flushing if needed, that would probably solve all of my issues. I'm sure for an expert ffmpeg'er modifying muxing.c addressing all those things would be a pretty quick exercise and could help more than 1 confused person.

  Thanks !

• How to create movie screenshot by ffmpeg in an amazon S3 path

  5 décembre 2019, par user2004082

  I tried to create using ffmpeg a video screenshot from a remote video url in heroku console. Below is how I generated a movie instance and can see also an empty ready to be written file at S3. But the last line movie.screenshot is not working and generates this error :

  FFMPEG::Error: Failed encoding.Errors: no output file created

  Here is the code

  s3 = Aws::S3::Resource.new(region: 'us-west-1')
  
  bucket = s3.bucket("ruby-sample-kb-#{SecureRandom.uuid}")
  
  bucket.create
  
  object = bucket.object('ex-vid-test-kb.jpg')
  
  object.put(acl: "public-read-write")
  
  path = object.public_url
  
  movie = FFMPEG::Movie.new("https://www.googleapis.com/download/storage/v1/b/seppoav/o/3606137_51447286560__56BAF29C-05CB-4223-BAE6-655DF2236321.MOV?generation=1492780072394755&alt=media")
  
  movie.screenshot(path, :seek_time => 2)

  I also tried the following line just if it should be written via put. What am I missing here ?

  object.put(acl: "public-read", body: movie.screenshot(path, :seek_time => 2))